FOR PREPARING THE SAME

FIELD OF INVENTION

[0001] The present invention relates to composite panel constructions and parcel chute system including a composite panel, and a process for preparing the same.

BACKGROUND OF THE INVENTION

[0002] Parcel chutes are commonly used in industrial and warehouse applications for moving and sorting boxes and other packages. Typically, the chute is configured in a sloped or spiral configuration between different floors or levels within a building to allow gravity to carry the packages down the chute. Often the parcel chute has a modular construction utilizing multiple panels or chute segments of different shapes and configurations to accommodate the different geometries of the parcel chute.

[0003] Parcel chutes must withstand not only heavy wear, but also the weight of the packages. Additionally, the contact surfaces of the parcel chutes require low friction resistance to allow the packages to slide thereon. Conventionally, steel or other metals have been used to construct the parcel chute panels and segments. However, steel panels are not only costly, but also require an extensive support structure to support the weight of the steel panels.

[0004] Hence, there is a need in the art for a parcel chute panel construction that provides the required high strength, while also being low in friction, cost and weight.

SUMMARY OF THE INVENTION

[0005] It has been found that the above-identified objects are met by providing a parcel chute comprising a plurality of chute segments secured together such that at least a portion of the parcel chute systems is positioned in an inclined configuration, and wherein at least one chute segment is a composite panel having a defined chemistry. In preferred embodiments, at least one chute segment of the parcel chute is a composite panel comprising (A) at least one mat layer, (B) a polyurethane film A prepared from a polyurethane resin composition A, wherein the polyurethane resin composition A is sprayed onto the at least one mat layer to form the polyurethane film A, (C) a honeycomb layer adjacent to the at least one mat layer and in contact with the polyurethane film, and (D) an overmolded polyurethane layer prepared from a polyurethane resin composition B adjacent to at least a portion of the at least one mat layer. In preferred embodiments, the polyurethane resin composition A is a reaction product of (1) an isocyanate component A, and (2) an isocyanate reactive component A comprising (a) at least one polyether polyol A having an average functionality of from 2.0 to 4.0, (b) at least one chain extender, and (c) at least two catalysts selected from amine catalysts and/or alkyl tin catalysts. Additionally, in preferred embodiments, the polyurethane resin composition B is a reaction product of (1) at least one isocyanate component B and (2) at least one isocyanate reactive component B and optionally at least one additive, and (3) at least one graphene component and/or at least one carbon black (CB) component.

[0006] The polyurethane A composition provides low viscosity (< 2000 cps at 23C) with better moldability, higher wettability, “no drip” performance, higher adhesion to thermoplastic, while maintaining a lower environmental toxicity versus conventional polyurethane resins.

[0007] In yet another aspect, this disclosure provides a parcel chute panel construction comprising (A) at least one mat layer, (B) a polyurethane film A prepared from a polyurethane resin composition A, wherein the polyurethane resin composition A is sprayed onto the at least one mat layer to form the polyurethane film A, (C) a honeycomb layer adjacent to the at least one mat layer and in contact with the polyurethane film, and (D) an overmolded polyurethane layer prepared from a polyurethane resin composition B adjacent to at least a portion of the at least one mat layer.

[0008] In another aspect, the presently claimed invention is directed to process for preparing a parcel chute panel construction, said process comprising the steps of (SI) spraying a polyurethane resin composition A onto at least one surface of a mat layer, wherein said polyurethane resin composition A forms a polyurethane film on the at least one surface of the mat layer resulting in a pre-impregnated blank, (S2) compression molding the pre-impregnated blank along with a honeycomb layer to obtain a spray-molded panel, and (S3) placing the spray- molded panel in an injection mold and injecting polyurethane composition B into the mold to the apply a polyurethane barrier layer to the spray -molded panel by reaction injection molding.

BRIEF DESCRIPTION OF THE FIGURES

[0009] Fig. 1 shows a perspective view of an exemplary spiral parcel chute system.

DETAILED DESCRIPTION OF THE INVENTION [0010] Before the present compositions and formulations of the invention are described, it is to be understood that this invention is not limited to particular compositions and formulations described, since such compositions and formulation may, of course, vary. It is also to be understood that the terminology used herein is not intended to be limiting, since the scope of the present invention will be limited only by the appended claims.

[0011] The terms "comprising", "comprises" and "comprised of' as used herein are synonymous with "including", "includes" or "containing", "contains", and are inclusive or open- ended and do not exclude additional, non-recited members, elements or method steps. It will be appreciated that the terms "comprising", "comprises" and "comprised of' as used herein comprise the terms "consisting of', "consists" and "consists of'.

[0012] Furthermore, the terms "first", "second", "third" or "(a)", "(b)", "(c)", "(d)" etc. and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operation in other sequences than described or illustrated herein. In case the terms "first", "second", "third" or “(A)”, “(B)” and “(C)” or "(a)", "(b)", "(c)", "(d)", "i", "ii" etc. relate to steps of a method or use or assay there is no time or time interval coherence between the steps, that is, the steps may be carried out simultaneously or there may be time intervals of seconds, minutes, hours, days, weeks, months or even years between such steps, unless otherwise indicated in the application as set forth herein above or below.

[0013] In the following passages, different aspects of the invention are defined in more detail. Each aspect so defined may be combined with any other aspect or aspects unless clearly indicated to the contrary. In particular, any feature indicated as being preferred or advantageous may be combined with any other feature or features indicated as being preferred or advantageous.

[0014] Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment, but may. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner, as would be apparent to a person skilled in the art from this disclosure, in one or more embodiments. Furthermore, while some embodiments described herein include some but not other features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention, and form different embodiments, as would be understood by those in the art. For example, in the appended claims, any of the claimed embodiments can be used in any combination.

[0015] Furthermore, the ranges defined throughout the specification include the end values as well, i.e. a range of 1 to 10 implies that both 1 and 10 are included in the range. For the avoidance of doubt, the applicant shall be entitled to any equivalents according to applicable law.

[0016] Aspects of this disclosure relate to a parcel chute wherein at least one chute segment of the parcel chute is a composite panel comprising (A) at least one mat layer, (B) a polyurethane film A prepared from a polyurethane resin composition A, wherein the polyurethane resin composition A is sprayed onto the at least one mat layer to form the polyurethane film A, (C) a honeycomb layer adjacent to the at least one mat layer and in contact with the polyurethane film, and (D) an overmolded polyurethane layer prepared from a polyurethane resin composition B adjacent to at least a portion of the at least one mat layer. In preferred embodiments, the polyurethane resin composition A is a reaction product of (1) an isocyanate component A, and (2) an isocyanate reactive component A comprising (a) at least one polyether polyol A having an average functionality of from 2.0 to 4.0, (b) at least one chain extender, and (c) at least two catalysts selected from amine catalysts and/or alkyl tin catalysts. Additionally, in preferred embodiments, the polyurethane resin composition B is a reaction product of (1) at least one isocyanate component B and (2) at least one isocyanate reactive component B and optionally at least one additive, and (3) at least one graphene component and/ or at least one carbon black (CB) component.

Parcel Chute System

[0017] An exemplary parcel chute system 100 is depicted in Fig. 1. As shown, the parcel chute system 100 has a spiral configuration to minimize its footprint, although a straight configuration is also possible where desired. In either case, the parcel chute system 100 generally includes a plurality of chute segments 101 secured together such that at least a portion of the parcel chute system 100 is positioned in an inclined configuration. The chute segments 101 may be secured together by any suitable means, including bolt fasteners, by interlocking “click-lock” engagements and the like.

[0018] As shown, the chute segments 101 provide a downward sloping channel for packages, envelopes and other parcels to be easily and passively transported between different elevations by gravity. An outer sidewall 103 and inner sidewall 105 are preferably formed on the respective outer and inner sides of the parcel contact surface 102 of chute segments 101. The outer sidewall 103 and inner sidewall 105 are generally raised above the parcel contact surface 102 of the chute segments 101 to form a boundary to retain packages and envelopes within the chute segments 101. [0019] The chute segments 101 may include one or more sloped segments 107 as well as a start section 109 and end section 111. The start section 109 works to provide a starting surface to place envelopes, boxes and other packages before they are thrust into the downward pitch of the chute segments 101. The end section 111 operates to slow envelopes and boxes moving along the surface of the chute segments 101.

[0020] As seen in Fig. 1, the spiral parcel chute system 100 is formed about a central axis of rotation where papers, envelopes, boxes and other articles move down the spiral chute 100. In some embodiments, at least one support structure 107, such as a central support rod, may be used to support the parcel chute system 100. In such examples, one or more of the chute segments 101 of the parcel chute system 100 may be provided with mounting elements 109 for mounting the chute segments 101 to the support structure 107.

[0021] Alternatively, in preferred embodiments, the parcel chute system 100 is free-standing. A free-standing configuration is possible because composite panels constructing the parcel chute system 100 are light-weight and do not require a separate support structure.

[0022] Preferably, at least one of the chute segments 101 of the parcel chute system 100 includes the composite parcel panel construction of this disclosure. In preferred examples, a majority or all of the chute segments 101 of the parcel chute system 100 may be formed from the composite parcel panel construction of this disclosure. However, it is also possible for a parcel chute system 100 to also include a combination of chute segments prepared from composite panels along with chute segments prepared from other materials, such as steel.

Parcel Chute Panel Construction

[0023] Another aspect of the present invention is directed towards a composite parcel chute panel construction. The parcel chute panel constructions of this disclosure may form one or more of the chute segments 101 the parcel chute system 100.

[0024] In preferred examples, the parcel chute panel construction comprises (A) at least one mat layer, (B) a polyurethane film A prepared from a polyurethane resin composition A, wherein the polyurethane resin composition A is sprayed onto the at least one mat layer to form the polyurethane film A, (C) a honeycomb layer adjacent to the at least one mat layer and in contact with the polyurethane film A, and (D) an overmolded polyurethane layer B prepared from a polyurethane resin composition B adjacent to with at least a portion of the at least one mat layer.

[0025] In some examples, the polyurethane resin composition A may be sprayed onto both major surfaces of the at least one mat layer and, alternatively or additionally, may infiltrate at least a portion of the at least one mat layer.

[0026] The overmolded polyurethane layer B may be applied to either or both major surfaces of the at least one mat layer and, alternatively or additionally, may infiltrate at least a portion of the at least one mat layer. In some examples, the overmolded polyurethane layer B may be applied to a portion of either or both major surfaces of the at least one mat layer having an area less than the total surface area of the mat layer.

[0027] Preferably, in the parcel chute panel construction, as described hereinabove, there is no requirement of an adhesive and/or a fastening means to bind the polyurethane film A onto the at least one mat layer or to bind the overmolded polyurethane barrier layer B to polyurethane film A or the mat layer. Advantages associated with the absence of an adhesive and/or fastening means are control on the thickness of the panel construction and faster and economical production of the panel construction.

[0028] As shown in Fig. 1, the parcel chute panel construction may be molded in various geometries to provide chute segments 101, including any of a sloped segment 107, start section 109 and end section 111. Preferably, a chute segment 101 is molded as a unitary article including a parcel contact surface 102 connected on opposing sides to an outer sidewall 103 and an inner sidewall 105. This advantageously allows for the chute segment 101 to have a seamless construction.

[0029] Preferably, the parcel chute panel construction has a thickness preferably of from 0.5 mm to 30 mm, or of from 0.5 mm to 20 mm or of from 0.5 mm to 10 mm.

[0030] Advantages of the panel constructions of this disclosure are that they are mechanically stable, are seamless panels, can employ a variety of colors via incorporation of pigments, have good thermal shock resistance, high strength, low weight, low friction, easy handling and mobility, and reduced production steps.

May Layer

[0031] Preferably, the mat layer, as described hereinabove, comprises non-woven fibers or fabric, woven fabrics or non-crimp fabrics. More preferably, the mats comprise non-woven fibers. [0032] Preferably, the non-woven fibers are natural, synthetic or glass fibers, or any combination thereof. Preferably, the synthetic fibers are selected from carbon fibers or polyester fibers. Preferably, the natural fibers are cellulosic bast fibers, bamboo fiber, jute fiber or kenaf fiber. Preferably, the non-woven fibers contain a synthetic thermoplastic fiber, for instance polyethylene terephthalate fibers (PET). The fibers can be synthetic polyester fibers or other fibers of similar characteristics.

[0033] More preferably, the mat layer comprises non-woven cellulosic bast fiber, jute fiber, kenaf fiber, bamboo fiber, non-woven polyester fiber, poly(methyl methacrylate), acrylonitrile butadiene styrene (ABS), polycarbonate, polypropylene, glass fiber, or a combination of two or more thereof. Even more preferably, the mat layer comprises non-woven cellulosic bast fiber, nonwoven polyester fiber, poly(methyl methacrylate) (PMMA), acrylonitrile butadiene styrene (ABS), polycarbonate, polypropylene, or a combination of two or more thereof. The polyurethane resin, as described herein, is highly compatible for use with other plastics such as PMMA, polyester, polycarbonate, polypropylene, and ABS and displays surprising adhesion behaviour with said plastics (as can be seen in example section hereinbelow).

[0034] Preferably, the mat layer comprises glass fibers. The presence of glass fibers embedded in the panel construction dramatically improves its dimensional stability, while all other desirable mechanical and processing properties are maintained. Suitable glass mat layers are well known to the person skilled in the art. For example, chopped glass fibers and continuous glass fibers can be used for this purpose.

[0035] Preferably, the mat layer is obtained from chopped glass fibers. The chopped glass fibers can be obtained in any shape and size. For instance, the chopped glass fibers can be, such as, a strand of fiber having a lateral and through-plane dimension or a spherical particle having diameter. The present invention is not limited by the choice of the shape and size of the chopped glass fibers as the person skilled in the art is aware of the same. Preferably, the chopped glass fiber has a length of from 10 mm to 150 mm, or of from 10 mm to 130 mm, or of from 10 mm to 100 mm.

[0036] Although, any suitable binding agent can be used for binding the chopped glass fibers, preferred is an acrylic binder. The acrylic binder is a cured aqueous based acrylic resin. The binder cures, for instance, through carboxylic groups and a multi-functional alcohol.

[0037] Acrylic binders are polymers or copolymers containing units of acrylic acid, methacrylic acid, their esters or related derivatives. The acrylic binders are for instance formed by aqueous emulsion polymerization employing (meth)acrylic acid (where the convention (meth)acrylic is intended to embrace both acrylic and methacrylic), 2-hydroxyethyl(meth)acrylate, 2-hydroxypropyl(meth)acrylate, 2-hydroxybutyl(meth)acrylate, methyl(meth)acrylate, ethyl(meth)acrylate, propyl(meth)acrylate, isopropyl(meth)acrylate, butyl(meth)acrylate, amyl(meth)acrylate, isobutyl(meth)acrylate, t-butyl(meth)acrylate, pentyl(meth)acrylate, isoamyl(meth)acrylate, hexyl(meth)acrylate, heptyl(meth)acrylate, octyl(meth)acrylate, isooctyl(meth)acrylate, 2-ethylhexyl(meth)acrylate, nonyl(meth)acrylate, decyl(meth)acrylate, isodecyl(meth)acrylate, undecyl(meth)acrylate, dodecyl(meth)acrylate, lauryl(meth)acrylate, octadecyl(meth)acrylate, stearyl(meth)acrylate, tetrahydrofurfuryl(meth)acrylate, butoxyethyl(meth)acrylate, ethoxydiethylene glycol (meth)acrylate, benzyl(meth)acrylate, cyclohexyl(meth)acrylate, phenoxyethyl(meth)acrylate, polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, methoxy ethylene glycol (meth)acrylate, ethoxyethoxyethyl(meth)acrylate, methoxypolyethylene glycol (meth)acrylate, methoxypolypropylene glycol (meth)acrylate, dicyclopentadiene(meth)acrylate, dicyclopentanyl(meth)acrylate, tricyclodecanyl(meth)acrylate, isobornyl(meth)acrylate, bomyl(meth)acrylate, or mixtures thereof.

[0038] Other monomers which can be co-polymerized with the (meth)acrylic monomers, generally in a minor amount, include styrene, diacetone(meth)acrylamide, isobutoxymethyl(meth)acrylamide, N-vinylpyrrolidone, N-vinylcaprolactam, N,N- dimethyl(meth)acrylamide, t-octyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N,N'- dimethyl-aminopropyl(meth)acrylamide, (meth)acryloylmorphorine; vinyl ethers such as hydroxybutyl vinyl ether, lauryl vinyl ether, cetyl vinyl ether, and 2-ethylhexyl vinyl ether; maleic acid esters; fumaric acid esters and similar compounds. The selection and amount of monomer may influence the adhesion of the PU with mat layer.

[0039] Multi-functional alcohols are for instance hydroquinone, 4,4'-dihydroxydiphenyl, 2,2- bis(4-hydroxyphenyl)propane, cresols or alkylene polyols containing 2 to 12 carbon atoms, including ethylene glycol, 1,2- or 1,3 -propanediol, 1,2-, 1,3- or 1,4-butanediol, pentanediol, hexanediol, octanediol, dodecanediol, di ethylene glycol, tri ethylene glycol, 1,3 -cyclopentanediol, 1,2-, 1,3- or 1,4-cyclohexanediol, 1,4-dihydroxymethylcyclohexane, glycerol, tris([3- hydroxyethyl)amine, trimethylolethane, trimethylolpropane, pentaerythritol, dipentaerythritol, tripentaerythritol and sorbitol. [0040] The aqueous based acrylic binders are commercially available under the ACRODUR® name from BASF.

[0041] Preferably, the aqueous based acrylic resin is infused in the mat. That is to say, the mat is impregnated with the acrylic resin. The mats are compressed and cured with heat and pressure. Pressure is not required for curing, but for setting a desired thickness or density or shape. Forming takes place for instance in a heated, shaped tool to a desired shape.

[0042] The aqueous based acrylic binder may be applied to the non-woven fibers or fabrics either through a dip-and-squeeze method, a curtain coater or a foam injection method. The mixture is dried to a low moisture content, preferably in an amount of from 4 wt.-% to 7 wt.-%, prior to thermal curing.

[0043] During initial heating and compression, compression release allows moisture to vent. The number of releases depends on the amount of moisture contained in the un-cured mat. The cured mat does not contain significant amounts of water. Preferably, the amount of water is of from 0 wt.-% to 3 wt.-% or based on the dry weight of the mat layer.

[0044] Once cured, the mat does not significantly swell. A preferred mat basis weight is of from 100 grams/square meter (gsm) to 1400 grams/square meter. The acrylic resin loading is preferably of from 15 wt.-% to 50 wt.-%, or of from 20 wt.-% to 40 wt.-% of dried resin, based on the finished mat weight.

[0045] Preferably, if the mat layer comprises continuous glass fibers, use of the binding agents, as described hereinabove, can be avoided. The present invention is not limited by the choice of the shape and size of the continuous glass fibers as the person skilled in the art is aware of the same. The continuous glass fibers can be oriented in one direction or in several directions, for instance, lateral, perpendicular or any angle between lateral and perpendicular. The mat layer comprising of continuous glass fibers has a nominal weight preferably of from 100 g/m ² to 1000 g/m ² .

[0046] The mat layer, as described hereinabove, preferably has an area weight preferably of from 100 g/m ² to 1500 g/m ² and a thickness preferably of from 0.5 mm to 30 mm. Suitable techniques to measure the area weight and thickness are well known to the person skilled in the art.

[0047] Preferably, the panel construction comprises more than one mat layer, e.g. two, three, four or five mat layers to form a multi-layered system. In such a case, the mats can be identical or different. They can be of the same basis weight or thickness or be of different basis weight or thickness. Also, the fibers employed in the multi-layered system can be same or different. The choice and selection of the number of layers and the mat therefor is well known to the person skilled in the art.

[0048] Preferably, the mat layer can be a hybrid layer comprising of at least one layer of chopped glass fibers or natural fibers and at least one layer of continuous glass fibers. More preferably, it can also contain a thin film or scrim to enhance surface quality. The said thin film or scrim can be inserted on top of the hybrid layer.

[0049] Preferably, the panel construction is a monolithic composite, also referred to as monolithic panel construction, comprising a single mat layer, the polyurethane film A, and overmolded polyurethane barrier layer, as described hereinabove. The said polyurethane film A is prepared from the polyurethane resin composition A which is sprayed onto the mat layer. In the present context, the term “polyurethane film A” refers to the atomized polyurethane resin composition which, when sprayed onto the mat layer, binds itself to the mat layer and has no thickness of its own. That is, to say, that the polyurethane film does not exists as a separate layer onto the mat layer. Also, the term “atomized” herein refers to the particles or droplets of the polyurethane resin composition obtained from suitable spraying means, such as but not limited to a nozzle or an atomizer.

[0050] Preferably, the polyurethane resin composition is sprayed onto the at least one mat layer in an amount of from 450 gsm to 1500 gsm, more preferably of from 450 gsm to 1200 gsm, even more preferably of from 450 gsm to 1000 gsm, most preferably of from 450 gsm to 900 gsm. Honeycomb Layer

[0051] Honeycomb panels have also been extensively used in the automotive, aerospace and shipbuilding industries, as described in US Pat. No. 7,972,676 and US Pat. No. 10,265,925. Generally, the honeycomb core includes plurality of individual cells formed by a plurality of walls extending between the first and second primary sides. The shape of the cells is not limited, and may include hexagonal, rectangular, triangular, round, linear and curviliear shapes. Hexagonal cells are preferred as they provide a minimum density for a given amount of material comprising the honeycomb core.

[0052] To reduce weight of the panel, the cells are preferably open cells filled with air or other gas. However, it is possible for some or all of the cells of the honey comb inner core to be filled with polymer resin to further increase strength.

[0053] Preferably, the honeycomb layer comprises at least one material selected from paper, cardboard, polypropylene, recycled thermoplastics, polycarbonate or aluminum. Polyurethane Resin Composition A

[0054] In preferred embodiments, the polyurethane resin composition A is a reaction product of (1) an isocyanate component A, and (2) an isocyanate reactive component A comprising (a) at least one polyether polyol A having an average functionality of from 2.0 to 4.0, (b) at least one chain extender, and (c) at least two catalysts selected from amine catalysts and/or alkyl tin catalysts.

[0055] (1) Isocyanate component A

[0056] In general, the isocyanates A can be present in monomeric form, in polymeric form, or as mixture of monomeric and polymeric forms. The term “polymeric” refers to the polymeric grade of the aliphatic, aromatic isocyanate, or mixtures thereof comprising dimers, trimers, higher homologues and/or oligomers.

[0057] Suitable isocyanates A include those known in the art, such as aliphatic, cycloaliphatic and aromatic di- or polyfunctional isocyanates and any mixtures thereof. Examples are diisocyanates, for example, trimethylene, tetramethylene, pentamethylene, hexamethylene, heptamethylene and/or octamethylene diisocyanate, 2-methylpentamethylene 1,5 -diisocyanate, 2- ethylbutylene 1,4-diisocyanate, pentamethylene 1,5 -diisocyanate, butylene 1,4-diisocyanate, 1- isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (isophorone diisocyanate, IPDI), 1,4- and/or l,3-bis(isocyanatomethyl)cyclohexane (HXDI), cyclohexane 1,4-diisocyanate, 1- methylcyclohexane 2,4- and/or 2,6-diisocyanate and/or dicyclohexylmethane 4,4'-, 2,4'- and 2,2' - diisocyanate, diphenylmethane 2,2'-, 2,4'- and/or 4,4'-diisocyanate (MDI), naphthylene 1,5- diisocyanate (NDI), tolylene 2,4- and/or 2,6-diisocyanate (TDI), diphenylmethane diisocyanate, 3,3 '-dimethylbiphenyl diisocyanate, 1,2-diphenylethane diisocyanate and/or phenylene diisocyanate. Further possible isocyanates are given, for example, in "Kunststoffhandbuch, Volume 7, Polyurethanes", Carl Hanser Verlag, 3rd edition 1993, Chapter 3.2 and 3.3.2.

[0058] Preferably, the isocyanate component A comprises methylene diphenyl diisocyanate, polymeric methylene diphenyl diisocyanate or a combination thereof. More preferably, the isocyanate is methylene diphenyl diisocyanate.

[0059] By the term “aromatic isocyanate”, it is referred to molecules having two or more isocyanate groups attached directly and/or indirectly to the aromatic ring. Preferably, the isocyanate component A is an aromatic isocyanate selected from toluene diisocyanate; polymeric toluene diisocyanate, methylene diphenyl diisocyanate (or monomeric MDI); polymeric methylene diphenyl diisocyanate; m-phenylene diisocyanate; 1,5 -naphthalene diisocyanate; 4- chloro-1; 3-phenylene diisocyanate; 2, 4, 6-toluylene triisocyanate, l,3-diisopropylphenylene-2,4- diisocyanate; l-methyl-3,5-diethylphenylene-2,4-diisocyanate; l,3,5-triethylphenylene-2,4- dii socy anate; 1,3,5 -trii soproply-phenylene-2,4-dii socy anate; 3 , 3 '-diethyl-bi sphenyl-4,4 '- diisocyanate; 3,5,3',5'-tetraethyl-diphenylmethane-4,4'-diisocyanate; 3, 5,3', 5'- tetraisopropyldiphenylmethane-4,4'-diisocyanate; l-ethyl-4-ethoxy-phenyl-2,5-diisocyanate;

1.3.5 -tri ethyl benzene-2,4,6-triisocyanate; l-ethyl-3,5-diisopropyl benzene-2,4,6-triisocyanate, tolidine diisocyanate, 1,3, 5 -triisopropyl benzene-2,4,6-triisocyanate or mixtures thereof. More preferably, the aromatic isocyanates is selected from toluene diisocyanate; polymeric toluene diisocyanate, methylene diphenyl diisocyanate; polymeric methylene diphenyl diisocyanate, m- phenylene diisocyanate; 1,5-naphthalene diisocyanate; 4-chloro-l; 3-phenylene diisocyanate;

2.4.6-toluylene triisocyanate, l,3-diisopropylphenylene-2,4-diisocyanate and l-methyl-3,5- diethylphenylene-2,4-diisocyanate or mixtures thereof. Even more preferably, the aromatic isocyanates is selected from toluene diisocyanate; polymeric toluene diisocyanate, methylene diphenyl diisocyanate; polymeric methylene diphenyl diisocyanate, m-phenylene diisocyanate, or 1,5-naphthalene diisocyanate or mixtures thereof. Still more preferably, the aromatic isocyanates is selected from toluene diisocyanate; polymeric toluene diisocyanate, methylene diphenyl diisocyanate, polymeric methylene diphenyl diisocyanate, or mixtures thereof. More preferably, the isocyanate is methylene diphenyl diisocyanate, or polymeric methylene diphenyl diisocyanate. [0060] Preferably, the aromatic isocyanates A are monomeric MDI and/or polymeric MDI. [0061] Preferably, the aromatic isocyanate(s) A is monomeric MDI. More preferably, monomeric MDI is selected from 4,4'-MDI, 2,2'-MDI and 2,4'-MDI, or combinations of two or more of the aforementioned.

[0062] Preferably, the aromatic isocyanate(s) A is polymeric MDI. Commercially available isocyanates available under the tradename, such as, Lupranat® from BASF can also be used for the purpose of the present invention.

[0063] More preferably, polymeric MDIs comprise of varying amounts of isomers, for example 4,4'-, 2,2'- and 2,4'-MDI. The amount of 4,4'MDI isomers is preferably from 26 wt.% to 98 wt.%, or more preferably from 30 wt.% to 95 wt.%, or even more preferably from 30 wt.% to 80 wt.%, with respect to the isomers, the balance being said oligomeric species. The methylene diphenyl diisocyanate isomers are often a mixture of 4,4'-methylene diphenyl diisocyanate, 2, d'methylene diphenyl diisocyanate and very low levels of 2,2'-methylene di-phenyl diisocyanate. [0064] From the context of present invention, the purity of the polymeric MDI or pMDI is not important. Preferably, the pMDI used according to the invention has an iron content of from 1 to 100 ppm, or 1 to 70 ppm, or 1 to 80 ppm, or 1 to 60 ppm, based on the total amount of the pMDI. [0065] Preferably, the pMDI has a NCO content in the range of from 22 to 40 wt.%, or 25 to 37 wt.%, or 28 to 35 wt.%, or 30 to 33 wt.%, based on total weight of pMDI.

[0066] Polymeric methylene diphenyl diisocyanate tends to have isocyanate functionalities of higher than 2. Preferably, the pMDI has a functionality of at least 2.3, or at least 2.5, or at least 2.7. More preferably, the pMDI has a functionality in the range from 2.3 to 4.5, or 2.5 to 4.3, or 2.5 to 4.0.

[0067] In addition, polymeric isocyanates include reaction products of polyisocyanates with polyhydric polyols and their mixtures with other diisocyanates and polyisocyanates can also be used.

[0068] Preferably, the isocyanate has an average functionality of at least 2.0; or of from 2.0 to 3.0. These isocyanates preferably comprise of aliphatic isocyanates or aromatic isocyanates or a combination thereof.

[0069] Preferably, the amount of isocyanates A in the polyurethane resin composition A is such that the isocyanate index is preferably of from 70 to 350, or of from 80 to 300, or of from 90 to 200, or of from 100 to 150. The isocyanate index of 100 corresponds to one isocyanate group per one isocyanate reactive group.

(2) Isocyanate reactive component A

[0070] The isocyanate reactive component A comprises (a) at least one polyether polyol A having an average functionality of from 2.0 to 4.0, (b) at least one chain extender, and (c) at least two catalysts selected from amine catalysts and/or alkyl tin catalysts.

[0071] The polyurethane resin composition A comprises at least one polyether polyol A having an average functionality of from 2.0 to 4.0. Preferably, the polyether polyols A are obtainable by known methods, for example by anionic polymerization or cationic polymerization.

[0072] For anionic polymerization, the polymerization of alkylene oxides having 2 to 4 carbon atoms in the alkylene moiety with addition of at least one starter molecule, comprising 1 to 4, preferably 2 to 3 and more preferably 2 reactive hydrogen atoms in bound form, in presence of an alkali metal hydroxides, e.g., sodium hydroxide or potassium hydroxide, or alkali metal alkoxides, e.g., sodium methoxide, sodium ethoxide, potassium ethoxide or potassium isopropoxide, as catalysts. [0073] For cationic polymerization, the polymerization of alkylene oxides having 2 to 4 carbon atoms in the alkylene moiety, with Lewis acids, such as antimony pentachloride, boron fluoride etherate and so on, or fuller’s earth, as catalysts. As catalysts it is additionally possible to use double metal cyanide compounds, known as DMC catalysts.

[0074] Starter molecules are generally selected such that their average functionality is preferably of from 2.0 to 8.0, or of from 3.0 to 8.0. Optionally, a mixture of suitable starter molecules is used.

[0075] Starter molecules for poly ether polyols A of polyurethane resin composition A include amine containing and hydroxyl-containing starter molecules. Suitable amine containing starter molecules include, for example, aliphatic and aromatic diamines such as ethylenediamine, propylenediamine, butylenediamine, hexamethylenediamine, phenylenediamines, toluenediamine, diaminodiphenylmethane and isomers thereof.

[0076] Other suitable starter molecules further include alkanolamines, e.g. ethanolamine, N- methylethanolamine and N-ethylethanolamine, dialkanolamines, e.g., diethanolamine, N- methyldi ethanolamine and N-ethyldi ethanolamine, and trialkanolamines, e.g., triethanolamine, and ammonia.

[0077] Preferred amine containing starter molecules comprise of ethylenediamine, phenylenediamines, toluenediamine or isomers thereof. Particularly preferred amine containing starter molecule is ethylenediamine.

[0078] Hydroxyl-containing starter molecules comprise of sugars, sugar alcohols, for e.g. glucose, mannitol, sucrose, pentaerythritol, sorbitol; polyhydric phenols, resols, e.g., oligomeric condensation products formed from phenol and formaldehyde, trimethylolpropane, glycerol, glycols such as ethylene glycol, propylene glycol and their condensation products such as polyethylene glycols and polypropylene glycols, e.g., diethylene glycol, triethylene glycol, dipropylene glycol, and water or a combination thereof.

[0079] Preferred hydroxyl containing starter molecules are sugar and sugar alcohols such as sucrose, sorbitol, glycerol, pentaerythritol, trimethylolpropane and mixtures thereof. In some embodiments the hydroxyl containing starter molecules are sucrose, glycerol, pentaerythritol and trimethylolpropane.

[0080] Suitable alkylene oxides having 2 to 4 carbon atoms are, for example, ethylene oxide, propylene oxide, tetrahydrofuran, 1,2-butylene oxide, 2,3 -butylene oxide and styrene oxide. Alkylene oxides can be used singly, alternatingly in succession or as mixtures. Preferred alkylene oxides are propylene oxide and/or ethylene oxide. In some preferred embodiments, the alkylene oxides are mixtures of ethylene oxide and propylene oxide that comprise more than 50 wt.-% of propylene oxide.

[0081] Preferably, the polyether polyol A of polyurethane resin composition A has a hydroxyl number of from 15 mg KOH/g to 1800 mg KOH/g as determined by DIN 53240. More preferably, the poly ether polyol has a hydroxyl number of from 45 mg KOH/g to 1700 mg KOH/g, even more preferably of from 60 mg KOH/g to 1600 mg KOH/g, more preferably of from 100 mg KOH/g to 1500 mg KOH/g, even more preferably of from 500 mg KOH/g to 1300 mg KOH/g, more preferably of from 500 mg KOH/g to 1100 mg KOH/g, most preferably of from 500 mg KOH/g to 1000 mg KOH/g as determined by DIN 53240.

[0082] Preferably, the polyether polyol A has a weight average molecular weight in the range of from 50 to 250 g/mol as determined by gel permeation chromatography. More preferably, the polyether polyol A has a weight average molecular weight in the range of from 80 to 220 g/mol, even more preferably of from 100 to 200 g/mol, most preferably of from 120 to 200 g/mol, as determined by gel permeation chromatography.

[0083] Preferably, the total poly ether polyol A content is in the range of from 35 to 65 wt.% with respect to the total weight of the polyurethane resin composition A. More preferably, the total polyether polyol content A is in the range of from 38 to 55 wt.%, even more preferably, of from 40 to 50 wt.%, with respect to the total weight of the polyurethane resin composition A.

[0084] According to the invention, the polyurethane resin composition A comprises at least one chain extender. Preferably, the chain extender is different from the poly ether polyol A. Chain extenders are preferably low molecular weight compounds having at least two isocyanate-reactive groups and having molecular weight less than 350 g/mol, more preferably of from 60 to less 300 g/mol, even more preferably of from 60 to less 200 g/mol. Chain extenders and/or cross linkers used are preferably alkanol amines and in particular diols and/or triols having molecular weights preferably of from 60 g/mol to 300 g/mol. Suitable amounts of these chain extenders and/or cross linkers can be added and are known to the person skilled in the art. Preferably, bifunctional chain extenders, trifunctional and higher-functional cross linkers or, if appropriate, mixtures thereof might be added.

[0085] Where low molecular weight chain extenders and/or crosslinking agents are used, it is possible to use chain extenders that are known in the context of polyurethane production, while chain extenders have a functionality of 2 and crosslinkers have a functionality of 3 or more. Chain extenders and/or crosslinking agents can be used to adjust mechanical properties such as hardness or elongation. This is known to a person skilled in the art. Examples of chain extenders and crosslinkers will include aliphatic, cycloaliphatic and/or araliphatic or aromatic diols having 2 to 14, preferably 2 to 10 carbon atoms, such as ethylene glycol, 1,3 -propanediol, 1,4-butanediol, 1,6-hexanediol, 1,10-decanediol and bis(2-hydroxyethyl)hydroquinone, 1,2-, 1,3-,

1,4-dihydroxy cyclohexane, di ethylene glycol, dipropylene glycol, tripropylene glycol, triols, such as 1,2,4-, 1,3,5-trihydroxycyclohexane, glycerol and trimethylolpropane, and hydroxyl-containing polyalkylene oxides of low molecular weight that are based on ethylene oxide and/or on 1,2-propylene oxide and on the aforementioned diols and/or triols as starter molecules. Further possible low molecular weight chain extenders and/or crosslinking agents are specified for example in "Kunststoffhandbuch, volume 7, Polyurethane", Carl Hanser Verlag, 3rd edition 1993, sections 3.2 and 3.3.2. If chain extender is used, it is preferably selected from, di ethylene glycol, ethylene glycol, propane diol, 1,4 butane diol, 1,6-hexane diol or di ethyltoluenediamine. More preferably chain extender is selected from, diethylene glycol, ethylene glycol, diethyltoluenediamine, or 1,4 butane diol. Even more preferably chain extender is selected from diethyltoluenediamine or diethylene glycol, most preferably chain extender is selected from di ethylene glycol.

[0086] Preferably, commercially available chain extenders that are reactive towards isocyanate can also be employed, for e.g. Sovermol®, Pluracol® and Quadrol® from BASF.

[0087] Preferably, the total chain extender content is in the range of from 1 to 15 wt.% with respect to the total weight of the polyurethane resin composition A. More preferably, the total chain extender content is in the range of from 1 to 12 wt.%, even more preferably of from 2 to 10 wt%., even more preferably of from 2 to 8 wt%., with respect to the total weight of the polyurethane resin composition A.

[0088] The polyurethane resin composition A preferably comprises at least two catalysts selected from amine catalysts and/or alkyl tin catalysts. Preferably amine catalysts are selected from diethyltoluenediamine, 4,4'-methylenebis(2-methylcyclohexyl-amine), or l-[bis[3- (dimethylamino)propyl]amino]-2-propanol. Preferably, the alkyl tin catalysts are selected from methyl organotin catalyst, butyl organo tin catalyst or octyl organotin catalyst. Methyl organotin catalysts that are well known in the art, are suitable for the present application. Preferably, the methyl organotin catalyst is dimethyltin dineodecanoate. Butyl organotin catalysts that are well known in the art, are suitable for the present application. Preferably, the butyl organotin catalyst is selected from dibutyltin dilaurate. Octyl organotin catalysts that are well known in the art, are suitable for the present application. Preferably, the octyl organotin catalyst is selected from dioctyltin dithioglycolate or dioctyltin mercaptide. Preferably, the alkyl tin catalysts are selected from dimethyltin dineodecanoate, dibutyltin dilaurate, dioctyltin dithioglycolate or dioctyltin mercaptide.

[0089] Preferably, the polyurethane resin composition A comprises a combination of two different amine catalysts or a combination of at least one amine and at least one alkyl tin catalyst. More preferably, polyurethane resin composition A comprises a combination of two different amine catalysts. Even more preferably, the polyurethane resin composition A comprises at least one amine catalyst and at least one alkyl tin catalyst.

[0090] Preferably, the polyurethane resin composition A comprises a combination of 1 -[bis[3 - (dimethylamino)propyl]amino]-2-propanol and one other catalyst selected from diethyltoluenediamine and dioctyltin dithioglycolate. More preferably, the polyurethane resin composition A comprises a combination of diethyltoluenediamine and l-[bis[3- (dimethylamino)propyl]amino]-2-propanol. Even more preferably, the composition comprises a combination of dioctyltin dithioglycolate and l-[bis[3-(dimethylamino)propyl]amino]-2- propanol.

[0091] More preferably, the polyurethane resin composition A comprises diethyltoluenediamine, dioctyltin dithioglycolate, and l-[bis[3-(dimethylamino)propyl]amino]-2- propanol.

[0092] The at least two catalysts selected from amine catalysts and/or alkyl tin catalysts, can be present in amounts preferably up to 20 wt.-%, more preferably from 0.5 to 17 wt%, even more preferably from 1 to 15 wt%, based on the total weight of the polyurethane resin composition A.

[0093] Optionally, the isocyanate reactive component A may include castor oil. Suitably, the castor oil in isocyanate reactive component A preferably comprises triglyceride of recinioleic acid in an amount > 50 wt% with respect to the castor oil. More preferably, the castor oil comprises triglyceride of recinioleic acid in an amount > 60 wt%, even more preferably in an amount > 70 wt%, more preferably in an amount > 80 wt%, even more preferably in an amount of 90 wt% with respect to the castor oil.

[0094] Preferably, if castor oil is included, the polyether polyol A to castor oil weight ratio in the polyurethane resin composition A is in the range of from 0.5 to 6.0. More preferably, the poly ether polyol A to castor oil weight ratio is in the range of from 0.7 to 4.8, even more preferably, of from 0.9 to 3.5.

[0095] Preferably, castor oil content in polyurethane resin composition A is in the range of from 25 to 60 wt.% with respect to the total weight of the polyurethane resin composition A. More preferably, castor oil content is in the range of from 28 to 45 wt.%, even more preferably of from 30 to 40 wt.%, most preferably of from 32 to 40 wt.%, with respect to the total weight of the polyurethane resin composition A.

[0096] Preferably, the polyurethane resin composition A further comprises auxiliary catalysts and additives. The auxiliary catalyst is different from the at least two catalysts selected from amine catalysts and/or alkyl tin catalysts. Suitable auxiliary catalyst for the polyurethane resin composition A is well known to the person skilled in the art. For instance, tertiary amine and phosphine compounds, metal catalysts such as chelates of various metals, acidic metal salts of strong acids; strong bases, alcoholates and phenolates of various metals, salts of organic acids with a variety of metals, organometallic derivatives of tetravalent tin, trivalent and pentavalent As, Sb and Bi and metal carbonyls of iron and cobalt and mixtures thereof can be used as catalysts.

[0097] Preferred tertiary amines are triethylamine, tributylamine, N-methylmorpholine, N- ethylmorpholine, N,N, N', N'-tetramethylethylenediamine, pentamethyl-diethylenetriamine and higher homologues (as described in, for example, DE- A 2,624,527 and 2,624,528), 1,4- diazabicyclo(2.2.2)octane, N-methyl-N'-dimethyl-aminoethylpiperazine, bis-

(dimethylaminoalkyl)piperazines, tris(dimethylaminopropyl)hexahydro-l,3,5-triazin, N,N- dimethylbenzylamine, N,N-dimethylcyclohexylamine, N,N-diethyl-benzylamine, bis-(N,N- di ethylaminoethyl) adipate, N,N,N',N'-tetram ethyl- 1,3 -butanediamine, N,N-dimethyl-p- phenylethylamine, 1 ,2-dimethylimidazole, 2-methylimidazole, monocyclic and bicyclic amines together with bis-(dialkylamino)alkyl ethers, such as 2,2-bis-(dimethylaminoethyl)ether. Triazine compounds, such as, tris(dimethylaminopropyl)hexahydro-l,3,5-triazin can also be used.

[0100] Preferred metal catalysts include metal salts and organometallics comprising tin-, titanium-, zirconium-, hafnium , bismuth-, zinc-, aluminium- and iron compounds, such as tin organic compounds, preferably tin alkyls, such as dimethyltin or diethyltin, or tin organic compounds based on aliphatic carboxylic acids, preferably tin diacetate, tin dilaurate, dibutyl tin diacetate, dibutyl tin dilaurate, bismuth compounds, such as bismuth alkyls or related compounds, or iron compounds, preferably iron-(Il)-acetylacetonate or metal salts of carboxylic acids, such as tin-II-isooctoate, tin dioctoate, titanium acid esters or bismuth-(III)-neodecanoate or a combination thereof.

[0101] The auxiliary catalysts, as described hereinabove, can be present in amounts preferably up to 20 wt.-% based on the total weight of the polyurethane resin composition A.

[0102] If present, additives can comprise one or more pigments, dyes, flame retardants, hindered amine light stabilizers, ultraviolet light absorbers, stabilizers, defoamers, internal release agents, desiccants, blowing agents and anti-static agents or a combination thereof. Further details regarding additives can be found, for example, in the Kunststoffhandbuch, Volume 7, “Polyurethane” Carl-Hanser-Verlag Munich, 1st edition, 1966 2nd edition, 1983 and 3rd edition, 1993. Suitable amounts of these additives are well known to the person skilled in the art. However, for instance, the additives can be present in amounts preferably up to 20 wt.-% based on the total weight of the polyurethane resin composition.

[0103] Preferably, the polyurethane resin composition A, as described hereinabove, can also comprise a reinforcing agent. Suitable reinforcing agents refer to fillers in the present context.

[0104] Suitable fillers include, such as, silicatic minerals, examples being finely ground quartzes, phyllosilicates, such as antigorite, serpentine, hornblendes, amphibols, chrysotile, and talc; metal oxides, such as kaolin, aluminum oxides, aluminium hydroxides, magnesium hydroxides, hydromagnesite, titanium oxides and iron oxides, metal salts such as chalk, heavy spar and inorganic pigments, such as cadmium sulfide, zinc sulfide, and also glass and others. Preference is given to using kaolin (china clay), finely ground quartzes, aluminum silicate, and coprecipitates of barium sulfate and aluminum silicate.

[0105] Preferred for use as fillers are those having an average particle diameter in the range of > 0.1 pm to < 500 pm, or more preferably in the range of > 1 pm to < 100 pm, or even more preferably in the range of > 1 pm to < 10 pm. Diameter in this context, in the case of non-spherical particles, refers to their extent along the shortest axis in space.

[0106] Suitable amounts of the fillers can be present in the polyurethane resin composition A which are known to the person skilled in the art. For instance, fillers can be present in an amount up to 50 wt.-%, based on the total weight of the polyurethane resin composition A.

[0107] Another aspect, the polyurethane resin composition A is obtainable by a process comprising reacting at least one isocyanate component A and at least one isocyanate-reactive composition A as described herein. [0108] Preferably, the molar ratio of the sum total of the functionalities of the isocyanatereactive composition A used to the sum total of the functionalities of the isocyanate component A used is in the range from 1 :0.8 to 1 : 1.3. More preferably, the molar ratio of the sum total of the functionalities of the isocyanate-reactive composition A used to the sum total of the functionalities of the isocyanate component A used is in the range from 1 :0.85 to 1 : 1.25; even more preferably, from 1 :0.9 to 1 : 1.20.

[0109] Preferably, polyurethane resin composition A is adaptable to spray molding. Spray transfer molding or spray molding is a process where atomized polyurethane particles are sprayed onto a non-woven material with a high-pressure nozzle or atomizer, then molded into the desired shape, providing a rigid, lightweight design. In a typical STM process, the first 60-90 seconds of the process is where the fabric is impregnated outside the mold using a high-pressure spray process, then molded in a compression press. A dry fiber or mat layer is held by a programmable robot that has an optimized and controlled spray pattern. It is then sprayed using a high-pressure nozzle head atomizing the polyurethane resin. This is followed by curing of the impregnated mat layer.

[0110] The resin of the present invention has a viscosity < 2000 cps at 23 C, thus making it highly suitable for spray molding techniques. Preferably, the resin has a viscosity < 1800 cps at 23 C, even more preferably < 1500 cps at 23 C.

Overmolded Polyurethane Barrier Layer

[oni] The parcel chute panels of this disclosure are provided with an overmolded polyurethane barrier layer on at least a portion thereof. The overmolded polyurethane layer B may be applied to one or both of the major surfaces of the panel construction or only a portion thereof. Preferably, the overmolded polyurethane layer B is applied to at least a parcel contact surface 102, which is in direct contact with the parcels during use. More preferably, the overmolded polyurethane layer B is applied to a parcel contact surface 102, outer sidewall 103 and inner sidewall 105. However, the overmolded polyurethane layer B may be selectively not applied to the sidewall 103 and inner sidewall 105.

[0112] To further reduce weight and materials cost, in some examples, the overmolded polyurethane layer B is not applied to the major surface of the panel construction that will form the underside of the chute construction.

[0113] The overmolded polyurethane layer B may be selectively applied to any combination of chute segments. For example, the overmolded polyurethane layer B may be applied to one or more (including all) sloped segments 107, but not to the start section 109 and/or end section 111. In some examples, the overmolded polyurethane layer B may be applied to either or both of the start section 109 and end section 111, but not one or more sloped segments 107. In some examples, the overmolded polyurethane layer B may be applied to each of the sloped segments 107, start section 109 and end section 111.

[0114] The thickness of the overmolded polyurethane barrier layer may be selected to balance between an increase in weight with obtaining sufficient thickness to reduce or prevent “read- through” of a surface texture of the mat layer. Suitable maximum thickness may be in a range of 5 mm or less, 4 mm or less, 3 mm or less, 2 mm or less, or 1 mm or less. Suitable minimum thickness may be in a range of 0.1 mm or more, 0.25 mm or more, 0.5 mm or more, or 0.75 mm or more.

Polyurethane Urethane Resin Composition B

[0115] In preferred embodiments, the polyurethane resin composition B is a reaction product of (1) at least one isocyanate component B and (2) at least one isocyanate reactive component B and optionally at least one additive, and (3) at least one graphene component and/ or at least one carbon black (CB) component.

[0116] Preferably, the reaction mixture includes the at least one graphene component and/ or at least one carbon black (CB) component in at least one of the isocyanate component B or the isocyanate reactive component B, or both. In a preferred embodiment, at least one graphene component and/ or at least one carbon black (CB) component is added to the isocyanate component B. In another preferred embodiment, the at least one graphene component and/ or at least one carbon black (CB) component is added to the isocyanate reactive component B.

Isocyanate component B

[0117] The isocyanates B can be selected from aliphatic isocyanates, aromatic isocyanates, and a combination thereof. By the term “aromatic isocyanate”, it is referred to molecules having two or more isocyanate groups attached directly and/or indirectly to the aromatic ring. Further, it is to be understood that the isocyanate component B includes both monomeric and polymeric forms of the aliphatic and aromatic isocyanate. By the term “polymeric”, it is referred to the polymeric grade of the aliphatic and/or aromatic isocyanate comprising, independently of each other, different oligomers, and homologues.

[0118] In another embodiment, the isocyanate component B comprises an aromatic isocyanate selected from toluene diisocyanate; polymeric toluene diisocyanate, methylene diphenyl diisocyanate; polymeric methylene diphenyl diisocyanate; m-phenylene diisocyanate; 1,5- naphthalene diisocyanate; 4-chloro-l; 3-phenylene diisocyanate; 2,4,6-toluylene triisocyanate, l,3-diisopropylphenylene-2,4-diisocyanate; l-methyl-3,5-diethylphenylene-2,4-diisocyanate; l,3,5-triethylphenylene-2,4-diisocyanate; l,3,5-triisoproply-phenylene-2,4-diisocyanate; 3,3'- diethyl-bisphenyl-4,4'-diisocyanate; 3,5,3',5'-tetraethyl-diphenylmethane-4,4'-diisocyanate; 3,5,3',5'-tetraisopropyldiphenylmethane-4,4'-diisocyanate; l-ethyl-4-ethoxy-phenyl-2,5- diisocyanate; 1,3, 5 -tri ethyl benzene-2,4,6-triisocyanate; l-ethyl-3,5-diisopropyl benzene-2,4,6- triisocyanate, tolidine diisocyanate, 1,3,5-triisopropyl benzene-2,4,6-triisocyanate and mixtures thereof. In other embodiment, the aromatic isocyanate component B is selected from toluene diisocyanate; polymeric toluene diisocyanate, methylene diphenyl diisocyanate; polymeric methylene diphenyl diisocyanate, m-phenylene diisocyanate; 1,5-naphthalene diisocyanate; 4- chloro-1; 3-phenylene diisocyanate; 2,4,6-toluylene triisocyanate, l,3-diisopropylphenylene-2,4- diisocyanate and l-methyl-3,5-diethylphenylene-2,4-diisocyanate. In other embodiments, the aromatic isocyanate component B is selected from toluene diisocyanate; polymeric toluene diisocyanate, methylene diphenyl diisocyanate; polymeric methylene diphenyl diisocyanate, m- phenylene diisocyanate and 1,5-naphthalene diisocyanate or a combination thereof. In still other embodiment, the aromatic isocyanate component B is selected from toluene diisocyanate; polymeric toluene diisocyanate, methylene diphenyl diisocyanate and polymeric methylene diphenyl diisocyanate or mixture thereof.

[0119] In another preferred embodiment, the aromatic isocyanate component B is selected from methylene diphenyl diisocyanate, polymeric methylene diphenyl diisocyanate or combination thereof.

[0120] In another preferred embodiment, the methylene diphenyl diisocyanate exists in three different isomeric forms, namely 2,2'-methylene diphenyl diisocyanate (2,2'-MDI), 2,4'-methylene diphenyl diisocyanate (2,4'-MDI) and 4,4'-methylene diphenyl diisocyanate (4,4'-MDI). Methylene diphenyl diisocyanate can be classified into monomeric methylene diphenyl diisocyanate and polymeric methylene di-phenyl diisocyanate referred to as technical methylene diphenyl diisocyanate. Polymeric methylene diphenyl diisocyanate includes oligomeric species and methylene diphenyl diisocyanate isomers. Thus, polymeric methylene diphenyl diisocyanate may contain a single methylene diphenyl diisocyanate isomer or isomer mixtures of two or three methylene diphenyl diisocyanate isomers, the balance being oligomeric species. Polymeric methylene diphenyl diisocyanate tends to have isocyanate functionalities of higher than 2. The isomeric ratio as well as the amount of oligomeric species can vary in wide ranges in these products. For instance, polymeric methylene diphenyl diisocyanate may typically contain 30 wt.- % to 80 wt.-% of methylene diphenyl diisocyanate isomers, the balance being said oligomeric species. The methylene diphenyl diisocyanate isomers are often a mixture of 4,4'-methylene diphenyl diisocyanate, 2,4'-methylene diphenyl diisocyanate and very low levels of 2,2'-methylene di-phenyl diisocyanate.

[0121] In another preferred embodiment, the isocyanate component B comprises a polymeric methylene diphenyl diisocyanate. Commercially available isocyanates available under the tradename, such as, but not limited to, Lupranate® from BASF can also be used for the purpose of the present invention.

[0122] In another preferred embodiment, the aliphatic isocyanate component B is selected from isophorone diisocyanate, propylene-l,2-diisocyanate, propylene- 1,3 -diisocyanate, butylene- 1,2-diisocyanate, butylene-l,3-diisocyanate, hexamethylene-l,6-diisocyanate, 2- methylpentamethylene-l,5-diisocyanate, 2-ethylbutylene-l,4-diisocyanate, 1,5-pentamethylene diisocyanate, ethyl ester 1-lysine triisocyanate, 1,6,11-triisocyanatoundecane, (2,4,6- trioxotriazine-l,3,5(2h,4h,6h)-triyl)tris(hexamethylene) isocyanate, methyl-2,6-diisocyanate caproate, octamethlyene-l,8-diisocyanate, 2,4,4-trimethylhexamethylene-l,6-diisocyanate, nonamethylene diisocyanate, 2,2,4-trimethylhexamethylene-l,6-diisocyanate, decamethylene- 1,10-diisocyanate, 2,11-diisocyanato-dodecane, triphe-nylmethane-4, 4 ’,4” -triisocyanate, toluene- 2,4,6-triyl triisocyanate, tris(isocyanatohexyl)biuret, trimethyl-cyclohexyl] triisocyanate, 2,4,4'- triisocyanato-dicyclohexylmethane, 2,2,-methylene-bis(cyclohexyl isocyanate), 3,3'-methylene- bis(cyclohexyl isocyanate), 4,4'-methylene-bis(cyclohexyl isocyanate), 4,4'-ethylene- bis(cyclohexyl isocyanate), 4,4'-propylene-bis-(cyclohexyl isocyanate), bis(paraisocyano- cyclohexyl)sulfide, bis(para-isocyanato-cyclohexyl)sulfone, bis(para-isocyano-cyclohexyl)ether, bis(para-isocyanato-cyclohexyl)diethyl silane, bis(para-isocyanato-cyclohexyl)diphenyl silane, bis(para-isocyanato-cyclohexyl)ethyl phosphine oxide, bis(para-isocyanato-cyclohexyl)phenyl phosphine oxide, bis(para-isocyanato-cyclohexyl)N-phenyl amine, bis(para-isocyanato- cyclohexyl)N-m ethyl amine,3,3-diisocyanato adamantane, 3, 3 -diisocyano biadamantane, 3,3- diiso-cyanatoethyl-l'-biadamantane, 1,2-bis (3-isocyanato-propoxy)ethane, 2,2-dimethyl propylene diisocyanate, 3-methoxy hexamethylene- 1,6-diisocyanate, 2,5-dimethyl heptamethylene diisocyanate, 5-methyl nonamethylene-l,9-diisocyanate, 1,4-diisocyanato cyclohexane, 1,2-diisocyanato octadecane, 2,5-diisocyanato-l,3,4-oxadiazole, OCN(CH2)3O(CH2)2O(CH2)3NCO and OCN(CH2)3N(CH3)(CH2)3NCO or polymeric forms of diisocyanates.; more preferably the aliphatic isocyanate selected from isophorone diisocyanate, propylene- 1 ,2-diisocyanate, propylene- 1 ,3 -diisocyanate, butylene- 1 ,2-diisocyanate, butylene- 1,3- diisocyanate, hexamethylene- 1,6-diisocyanate, 2-methylpentamethylene-l,5-diisocyanatel,5- pentam ethylene diisocyanate, 1,6,11-triisocyanatoundecane, methyl-2,6-diisocyanate caproate, octamethlyene-l,8-diisocyanate, 2, 4, 4-trimethylhexamethylene- 1,6-diisocyanate, nonamethylene diisocyanate, 2,2,4-trimethylhexamethylene-l,6-diisocyanate, decamethylene-1, 10-diisocyanate, 2,11-diisocyanato-dodecane or polymeric forms of diisocyanates; and most preferably the aliphatic isocyanate selected from isophorone diisocyanate, hexamethylene-l,6-diisocyanate, 2- methylpentamethylene-l,5-diisocyanate, 1,5-pentamethylene diisocyanate, loctamethlyene-1,8- diisocyanate, 2,4,4-trimethylhexamethylene-l,6-diisocyanate, nonamethylene diisocyanate, 2,2,4- trimethylhexamethylene- 1,6-diisocyanate, decamethylene- 1, 10-diisocyanate, 2,11-diisocyanato- dodecane and polymeric forms of diisocyanates or mixtures thereof.

[0123] In another embodiment, the at least one isocyanate component B has an isocyanate functionality ranging from 2.0 to 4.0. In one embodiment, the isocyanate component B comprises an isocyanate having an isocyanate functionality ranging from 1.5 to 3.0. Preferably, the isocyanate functionality of the isocyanate component B ranges from 1.6 to 3.0, or from 1.7 to 3.0, or from 1.8 to 3.0, or from 1.9 to 3.0. More preferably, the isocyanate functionality of the isocyanate component B ranges from 1.9 to 2.9, or from 1.9 to 2.8, or from 1.9 to 2.7.

[0124] The isocyanate component B content is in an amount from 1 wt.% to 60 wt.% of the polyurethane resin composition B. Preferably, the isocyanate component of the isocyanate is from 1 wt.-% to 55 wt.%, or from 5 wt.% to 55 wt.%, or from 10 wt.% to 55 wt.%, or from 15 wt.% to 55 wt.% of the polyurethane resin composition B. More preferably, the isocyanate component B of the polyurethane resin composition B is from 20 wt.% to 55 wt.%, or from 23 wt.% to 55 wt.%, or from 25 wt.% to 55 wt.%.

[0125] Preferably, the isocyanate component B is selected from a 2,2'-, 2,4'- and/or 4,4'- diisocyanate, a hexamethylene diisocyanate (HDI), or Hydrogenated MDI or a carbodiimide modified MDI. In another preferred embodiment, the at least one isocyanate component B is selected from 4,4 '-diphenylmethane diisocyanate, polymeric MDI, carbodiimide modified MDI, MDI prepolymer or combination thereof.

[0126] In another embodiment, the isocyanate component B comprises at least two isocyanates, the first isocyanate and the second isocyanate. The first isocyanate is as described hereinabove. The second isocyanate has an isocyanate functionality of at least 2.0, said second isocyanate being different than the first isocyanate. Suitable second isocyanates have an isocyanate content of at least 5.0 wt.%. Preferably, the second isocyanate in the isocyanate composition have an isocyanate content in range from 5 wt.% to 40 wt.%, or in range from 6 wt.% to 30 wt.%, or in range from 7 wt.% to 20 wt.%, the said second isocyanates being different than the first isocyanate. [0127] Preferably, the second isocyanate in the isocyanate component B is selected from a prepolymer based on carbodiimide-modified diphenylmethane 2,2'-, 2,4'- and/or 4, 4'-diisocyanate. [0128] In one embodiment, the isocyanate component B comprises a mixture of the first isocyanate and the second isocyanate. The weight ratio between the first isocyanate and the second isocyanate in the isocyanate component B is in a range from 2.0: 1.0 to 1.0: 2.0. Preferably, the weight ratio between the first isocyanate and the second isocyanate in the isocyanate component B is in a range from 2.0: 1.0 to 1.0: 1.5 or from 2.0: 1.0 to 1.0: 1.3, or from 2.0: 1.0 to 1.0: 1.0. More preferably, the weight ratio between the first isocyanate and the second isocyanate in the isocyanate component B is in a range from 1.9: 1.0 to 1.0: 1.0, or from 1.8: 1.0 to 1.0: 1.01, or from 1.7: 1. O to 1.0: 1.0.

Isocyanate reactive component B

[0129] In a preferred embodiment, the isocyanate reactive component B comprises at least one polyol B. In a preferred embodiment, the isocyanate reactive component B is a polyol having an average functionality in the range of 2.0 to 8.0 and the hydroxyl number in the range of 15 mg KOH/g to 1800 mg KOH/g. The compounds that are reactive towards isocyanate can be present in an amount in the range of 1 wt.% to 99 wt.%, based on the total weight of the reaction mixture. [0130] The polyol B includes poly ether polyols, polyester polyols, poly etherester polyols, and a combination thereof. Polyether polyols are obtainable by known methods, for example by anionic polymerization with alkali metal hydroxides, e.g., sodium hydroxide or potassium hydroxide, or alkali metal alkoxides, e.g., sodium methoxide, sodium ethoxide, potassium ethoxide or potassium isopropoxide, as catalysts and by adding at least one amine-containing starter molecule, or by cationic polymerization with Lewis acids, such as antimony pentachloride, boron fluoride etherate and so on, or fuller’s earth, as catalysts from one or more alkylene oxides having 2 to 4 carbon atoms in the alkylene moiety.

[0131] Starter molecules are generally selected such that their average functionality is preferably in the range of 2.0 to 8.0, and more preferably in the range of 3.0 to 8.0. Optionally, a mixture of suitable starter molecules is used. [0132]

[0133] Starter molecules for polyether polyols include amine containing and hydroxylcontaining starter molecules. Suitable amine containing starter molecules include, for example, aliphatic and aromatic diamines such as ethylenediamine, propylenediamine, butylenediamine, hexamethylenediamine, phenylenediamines, toluenediamine, diaminodiphenylmethane and isomers thereof.

[0134] Other suitable starter molecules further include alkanolamines, e.g. ethanolamine, N- methylethanolamine and N-ethylethanolamine, dialkanolamines, e.g., diethanolamine, N- methyldi ethanolamine and N-ethyldi ethanolamine, and trialkanolamines, e.g., triethanolamine, and ammonia.

[0135] Suitable amine containing starter molecules are selected from ethylenediamine, phenylenediamines, toluenediamine or isomers thereof. In one embodiment, it is ethylenediamine. [0136] Hydroxyl-containing starter molecules are selected from sugars, sugar alcohols, for e.g. glucose, mannitol, sucrose, pentaerythritol, sorbitol; polyhydric phenols, resols, e.g., oligomeric condensation products formed from phenol and formaldehyde, trimethylolpropane, glycerol, glycols such as ethylene glycol, propylene glycol and their condensation products such as polyethylene glycols and polypropylene glycols, e.g., diethylene glycol, triethylene glycol, dipropylene glycol, and water or a combination thereof.

[0137] Suitable hydroxyl containing starter molecules are selected from sugar and sugar alcohols such as sucrose, sorbitol, glycerol, pentaerythritol, trimethylolpropane or mixtures thereof. In some embodiments the hydroxyl containing starter molecules are selected from sucrose, glycerol, pentaerythritol or trimethylolpropane.

[0138] Suitable alkylene oxides having 2 to 4 carbon atoms are, for example, ethylene oxide, propylene oxide, tetrahydrofuran, 1,2-butylene oxide, 2,3 -butylene oxide, and styrene oxide. Alkylene oxides can be used singly, altematingly in succession or as mixtures. In one embodiment, the alkylene oxides are propylene oxide and/or ethylene oxide. In some embodiments, the alkylene oxides are mixtures of ethylene oxide and propylene oxide that comprise more than 50 wt.% of propylene oxide.

[0139] In another preferred embodiment, the polyester polyols of polyol B are based on the reaction product of carboxylic acids or anhydrides with hydroxy group containing compounds. Suitable carboxylic acids or anhydrides have preferably from 2 to 20 carbon atoms, or from 4 to 18 carbon atoms, for example succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, decanedicarboxylic acid, maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, oleic acid, phthalic anhydride. Particularly comprising of phthalic acid, isophthalic acid, terephthalic acid, oleic acid and phthalic anhydride or a combination thereof.

[0140] Suitable hydroxyl containing compounds are selected from ethanol, ethylene glycol, propylene- 1,2-gly col, propylene-l,3-glycol, butyl-ene-l,4-glycol, bu-tylene-2, 3 -glycol, hexane-

1.6-diol, octane- 1,8 -diol, neopentyl glycol, cyclohexane dimethanol (1,4-bis-hydroxy- methylcyclohexane), 2-methyl-propane- 1,3 -diol, glycerol, trimethylolpropane, hexane- 1, 2, 6-triol, butane -1,2,4-triol, trimethylol ethane, pentaerythritol, quinitol, mannitol, sorbitol, methyl glycoside, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, dipropylene glycol, polypropylene glycol, polyethylenepropylene glycol, dibutylene glycol or polybutylene glycol. In one embodiment, the hydroxyl containing compound is selected from ethylene glycol, propylene- 1,2-gly col, propylene-l,3-glycol, butylene- 1,4-gly col, butylene-2,3- glycol, hexane-l,6-diol, octane- 1,8-diol, neopentyl glycol, cyclohexane dimethanol (1,4-bis- hydroxy-methylcyclohexane), 2-methyl-propane-l,3-diol, glycerol, trimethylolpropane, hexane-

1.2.6-triol, butane -1,2,4-triol, trimethylolethane, pentaerythritol, quinitol, mannitol, sorbitol, methyl glycoside or diethylene glycol. In another embodiment, the hydroxyl containing compound is selected from ethylene glycol, propylene- 1,2-gly col, pro-pylene- 1,3 -glycol, butyl-ene-1,4- glycol, butylene-2,3-glycol, hexane-l,6-diol, octane- 1,8-diol, neopentyl glycol or diethylene glycol. In still another embodiment, the hydroxyl containing compound is selected from hexane-

1.6-diol, neopentyl glycol and di ethylene glycol.

[0141] Such polyetherester polyols of polyol B are obtainable as a reaction product of i) at least one hydroxyl-containing starter molecule; ii) of one or more fatty acids, fatty acid monoesters or mixtures thereof; iii) of one or more alkylene oxides having 2 to 4 carbon atoms.

[0142] The starter molecules of component i) are generally selected such that the average functionality of component i) is preferably 3.8 to 4.8, or from 4.0 to 4.7, or even from 4.2 to 4.6. Optionally, a mixture of suitable starter molecules is used.

[0143] Suitable hydroxyl containing starter molecules of component i) are selected from sugars, sugar alcohols (glucose, mannitol, sucrose, pentaerythritol, sorbitol), polyhydric phenols, resols, e.g., oligomeric condensation products formed from phenol and formaldehyde, trimethylolpropane, glycerol, glycols such as ethylene glycol, propylene glycol and their condensation products such as polyethylene glycols and polypropylene glycols, e.g., diethylene glycol, triethylene glycol, dipropylene glycol, and water or a combination thereof. [0144] In another preferred embodiment, the hydroxyl containing starter molecules of component i) are selected from sugars and sugar alcohols such as sucrose and sorbitol, glycerol, and mixtures of said sugars and/or sugar alcohols with glycerol, water and/or glycols such as, for example, diethylene glycol, dipropylene glycol or combination thereof.

[0145] Said fatty acid or fatty acid monoester ii) is selected from polyhydroxy fatty acids, ricinoleic acid, hydroxyl-modified oils, hydroxyl-modified fatty acids and fatty acid esters based in myristoleic acid, palmitoleic acid, oleic acid, stearic acid, palmitic acid, vaccenic acid, petroselic acid, gadoleic acid, erucic acid, nervonic acid, linoleic acid, a- and g-linolenic acid, stearidonic acid, arachidonic acid, timnodonic acid, clupanodonic acid and cervonic acid or a combination thereof. Fatty acids can be used as purely fatty acids. In this regard, preference is given to using fatty acid methyl esters such as, for example, biodiesel or methyl oleate.

[0146] Biodiesel is to be understood as meaning fatty acid methyl esters within the meaning of the EN 14214 standard from 2010. Principal constituents of biodiesel, which is generally produced from rapeseed oil, soybean oil or palm oil, are methyl esters of saturated C 16 to Cl 8 fatty acids and methyl esters of mono- or polyunsaturated C18 fatty acids such as oleic acid, linoleic acid and linolenic acid.

[0147] Suitable alkylene oxides iii) having 2 to 4 carbon atoms are, for example, ethylene oxide, propylene oxide, tetrahydrofuran, 1,2-butylene oxide, 2,3-butylene oxide and/or styrene oxide. Alkylene oxides can be used singly, alternatingly in succession or as mixtures.

[0148] In another preferred embodiment, the alkylene oxides comprise propylene oxide and ethylene oxide. In another preferred embodiment, the alkylene oxide is a mixture of ethylene oxide and propylene oxide comprising more than 50 wt.% of propylene oxide. In another embodiment, the alkylene oxide comprises purely propylene oxide.

[0149] In another preferred embodiment, the at least one polyol B has an average functionality in the range of 2.0 to 8.0, the hydroxyl number in the range of 20 mg KOH/g to 800 mg KOH/g and the nominal molecular weight in the range of 200 g/ mole to 6000 g/ mole.

[0150] Preferably, the polyol B has an OH value ranging from 20 mg KOH/g to 800 mg KOH/g, or from 20 mg KOH/g to 750 mg KOH/g, or from 20 mg KOH/g to 700 mg KOH/g, or from 20 mg KOH/g to 650 mg KOH/g, or from 20 mg KOH/g to 600 mg KOH/g. In another preferred embodiment, the polyol B has OH value ranging from 25 mg KOH/g to 600 mg KOH/g, or from 30 mg KOH/g to 600 mg KOH/g, or from 40 mg KOH/g to 600 mg KOH/g, 50 mg KOH/g to 600 mg KOH/g. In another preferred embodiment, the polyol B has OH value ranging from 100 mg KOH/g to 600 mg KOH/g, or from 200 mg KOH/g to 600 mg KOH/g, or from 300 mg KOH/g to 600 mg KOH/g, or from 350 mg KOH/g to 600 mg KOH/g.

[0151] Preferred polyol B has a molecular weight distribution from 100 g/ mol to 6000 g/ mol, or from 200 g/ mol to 6000 g/ mol, or from 300 g/ mol to 6000 g/ mol, or from 350 g/ mol to 6000 g/ mol. In yet another embodiment, the polyol B have a molecular weight distribution from 350g/ mol to 4500 g/ mol, or from 350 g/ mol to 4000 g/ mol, or from 350 g/ mol to 3500 g/ mol, or from 350 g/ mol to 3000 g/ mol, or from 350 g/ mol to 3000 g/ mol, or from 350 g/ mol to 2500 g/ mol, or from 350 g/ mol to 2450 g/ mol, or from 350 g/ mol to 2400 g/ mol, or from 350 g/ mol to 2350 g/ mol.

[0152] Suitable polyols in the polyol B are preferably selected from Polytetrahydrofurane (PolyTHF), polyether polyols, polyester polyols, or polycarbonate polyols. In one embodiment, the polyol comprises a PolyTHF. In another preferred embodiment, the at least one polyol B is poly ether polyols, polyester polyols, poly etherester polyols, polytetrahydrofuran, or a combination thereof.

[0153] In another preferred the polyol B is a polyol mixture (i) based on the mixture of at least two, preferably separately prepared polyol. By the expression "at least two polyol" it is meant that two different polyols are used, which have different mean molecular weight data.

[0154] In another preferred the polyol B is a polyol mixture (i) based on the mixture of at least three, preferably separately prepared polyol. By the expression "at least three polyol" it is meant that three different polyols are used, which have different mean molecular weight data.

[0155] The combination of more than one polyol is associated with obtaining a lower Coefficient of Friction (CoF) value. The polyurethane resin composition B with polyol(s) having an average functionality of about 3.5 to 4.0 are associated with the lowest CoF. Using a polyol with lower functionality resulted in higher CoF.

[0156] Graphene and Carbon Black (CB)

[0157] The reaction mixture for the polyurethane resin composition B may include graphene. The graphene is added either in the isocyanate component B or the isocyanate reaction component B or both parts of the reaction mixture.

[0158] In an embodiment, the graphene includes monolayer graphene, few-layer graphene (FLG), multi-layer graphene (MLG), graphene nano-platelets (GNP), graphite oxides (GO), graphite ore, reduced graphene oxides (rGO), graphene quantum dots, graphene ribbons, suspended graphene particles or membranes thereof, graphene master batches thereof, or combination thereof.

[0159] In a preferred embodiment, the graphene component in the polyurethane resin composition B is in range from 0.01 wt.% to 10.0 wt.%, or 0.01 to 9.5 wt.% or, from 0.01 wt.% to 9.0 wt.%, or from 0.01 wt.% to 8.5 wt.%, or from 0.01 wt.% to 8.0.0 wt.%, or from 0.01 wt.% to 7.5 wt.%, or from 0.01 wt.% to 7.0 wt.%, or from 0.01 wt.% to 6.5 wt.%, or from 0.01 wt.% to 6.0 wt.%, or from 0.01 wt.% to 5.5 wt.%, or from 0.01 wt.% to 5.0 wt.% of the polyurethane resin composition B. In a more preferred embodiment, the graphene component is in range from 0.05 wt.% to 5.0 wt.%, or from 0.10 wt.% to 5.0 wt.%, or from 0.15 wt.% to 5.0 wt.%, or from 0.20 wt.% to 5.0 wt.%, or from 0.25 wt.% to 5.0 wt.%, or from 0.30 wt.% to 5.0 wt.%, or from 0.35 wt.% to 5.0 wt.%, or from 0.40 wt.% to 5.0 wt.% of the polyurethane resin composition B.

[0160] In a preferred embodiment, the graphene is in form of the GNP, an oxidized form of graphene, functionalized with oxygen-containing groups. The GNP is described to have a single platelet structure, i.e., single atomic layer structure or as having a multi -platelet structure.

[0161] In a preferred embodiment, the GNP has layer structure with layers in range from 1 to 40 layers, or from 1 to 35 layers, or from 1 to 30 layers, or from 1 to 25 layers, or from 1 to 20 layers. In a more preferred embodiment, the GNP has a layer structure with layers in from 2 to 20 layers, or from 3 to 20 layers, or from 4 to 20 layers. In a more preferred embodiment, the GNP has a layer structure with layers in range from 4 to 15 layers or from 1 to 10 layers.

[0162] In another preferred embodiment, the GNP has a particle size in range of 0.5 pm to 200 pm or from 0.5 pm to 150 pm or from 0.5 pm to 100 pm, or from 0.5 pm to 90 pm. In a more preferred embodiment the particle size is in range from 0.5 pm to 80 pm, or from 0.5 pm to 70 pm, or from 0.5 pm to 60 pm, or from 0.5 pm to 50 pm, or from 0.5 pm to 40 pm, or from 0.5 pm to 30 pm, or from 0.5 pm to 20 pm. In a furthermore preferred embodiment, the particle size is in range from 0.5 pm to 10 pm, or from 0.5 pm to 5 pm.

[0163] In another preferred embodiment, the graphene has an agglomeration size in range from 1 pm to 100 pm. In a further preferred embodiment, the graphene has an agglomeration size distribution of D10 (from 1.0 to 4.0 pm), D50 (from 6.0 to 14.0 pm), and D90 (30.0 to 36 pm). D10, D50 and D90 denote percentage of particles (10%, 50% and 90%) in a size range.

[0164] In a preferred embodiment, the GNP has a short stack of graphene sheets having a platelet shape. The GNP has an average thickness of approximately 6 to 8 nm. [0165] In another preferred embodiment, the GNP has a typical surface area in range from 100 to 500 m ² /g, or from 100 to 450 m ² /g, or from 100 to 400 m ² /g. In a more preferred embodiment, the typical surface area of the GNP is in range of 100 to 350 m ² /g,

[0166] In some embodiments, the reaction mixture for the polyurethane resin composition B may include carbon black (CB). The carbon black is added either in the isocyanate component B or the isocyante reactive component B or both part of the reaction mixture.

[0167] In an embodiment, the carbon black includes acetylene black, furnace black, gas black, lamp black, thermal black, conductive black, HNO3-treated CB, ammonia treated CB, doped CB, CB mixed with iron phthalocyanine, recycled CB or combination thereof.

[0168] In a preferred embodiment, the carbon black includes a conductive black, with a sieve residue (325 mesh) calculated by ASTM D 1514 in range from 0.01 to 200 ppm, or from 0.01 to 150 ppm, or from 0.01 to 100 ppm, or from 0.01 to 90 ppm, or from 0.01 to 80 ppm, or from 0.01 to 70 ppm, or from 0.01 to 60 ppm.

[0169] In another preferred embodiment the carbon black has a sulphur content measured by ASTM D 1506 in range from 0.001 to 5.0 %, or from 0.001 to 4.0 %, or from 0.001 to 3.0 %, or from 0.001 to 2.0%, or from 0.001 to 1.0 % of the carbon black component.

[0170] In yet another preferred embodiment, the carbon black has a total surface area measured by ASTM D 6556 in range from 50 to 2000 m ² /g, or from 50 to 1900 m ² /g, or from 50 to 1800 m ² /g, or from 50 to 1700 m ² /g, or from 50 to 1600 m ² /g, or from 50 to 1500 m ² /g, from 50 to 1400 m ² /g, or from 50 to 1300 m ² /g, or from 50 to 1200 m ² /g. In a more preferred embodiment, the carbon black has total surface area in range from 60 to 1200 m ² /g, or from 70 to 1200 m ² /g, or from 80 to 1200 m ² /g, or from 90 to 1200 m ² /g, or from 100 to 1200 m ² /g. The ASTM D 6556 for total surface are determined by Brunauer, Emmett, and Teller (B.E.T. NSA) theory of multilayer gas adsorption behavior using multipoint determinations.

[0171] In a preferred embodiment, the carbon black includes a conductive black, with a sieve residue (45 mesh) calculated by ISO 787 18, in range from 0.01 to 200 ppm, or from 0.01 to 150 ppm, or from 0.01 to 100 ppm, or from 0.01 to 90 ppm, or from 0.01 to 80 ppm, or from 0.01 to 70 ppm, or from 0.01 to 60 ppm.

[0172] In another preferred embodiment the carbon black has a sulphur content measured by ASTM D 1619 in range from 0.001 to 5.0 %, or from 0.001 to 4.0 %, or from 0.001 to 3.0 %, or from 0.001 to 2.0%, or from 0.001 to 1.0 % of the carbon black component. [0173] In a preferred embodiment, the carbon black component in the polyurethane resin composition B is in range from 0.01 to 10.0 wt.%, or from 0.01 to 9.5 wt.%, or from 0.01 to 8.5 wt.%, or from 0.01 to 8.0 wt.% of the polyurethane resin composition B.

[0174] In a more preferred embodiment, the carbon black component in the polyurethane resin composition B is in range from 0.01 to 7.5 wt.%, or from 0.01 to 7.0 wt.% or from 0.01 to 6.0 wt.%, or from 0.01 to 5.5 wt.% or from 0.01 to 5.0 wt.% or from 0.01 to 4.5 wt.% or from 0.01 to 4.0 wt.% of the polyurethane resin composition B.

[0175] Suitable commercially available examples of carbon black and graphene include PRINTEX® XE2 B BEADS and PRINTEX® kappa 70, both available from Orion Engineered Carbons; HC-20435 CONDUCTIVE BLACK “DR,” COLORMATCH™ HC-02926, HC-02926 CONDUCTIVE PF, and COLORMATCH™ HC-20435 available from Chromaflo Technologies; and GrapheneBlack™ OX and GrapheneBlack™ 3X, both available from NanoXplore, Inc.

[0176] In another embodiment, the reaction mixture used to prepare the polyurethane resin composition B includes both carbon black and graphene. In a preferred embodiment, the reaction mixture used to prepare the polyurethane resin composition B includes both carbon black and graphene in the isocyanate component B. In another preferred embodiment, the reaction mixture used to prepare the polyurethane resin composition B includes both carbon black and graphene in isocyanate reactive composition B.

[0177] In yet another preferred embodiment, the combination of CB and graphene is in range from 0.5 wt. % to 30.0 wt. %, or from 0.5 wt.% to 28.0 wt.%, or from 0.5 wt.% to 26.0 wt.%, or from 0.5 wt.% to 24.0 wt.%, or from 0.5 wt.% to 22.0 wt.%, or from 0.5 wt.% to 20.0 wt.%, or from 0.5 wt.% to 18.0 wt.%, or from 0.5 wt.% to 16.0 wt.%, or from 0.5 wt.% to 14.0 wt.%, or from 0.5 wt.% to 12.0 wt.%, or from 0.5 wt.% to 10.0 wt.%, or from 0.5 wt.% to 8.0 wt.% of the polyurethane resin composition B. In a more preferred embodiment, the combination of CB and graphene is in range from 1.0 wt.% to 8.0 wt.%, or from 1.5 wt.% to 8.0 wt.% of the polyurethane resin composition B.

[0178] In yet another preferred embodiment, the ratio of the graphene component to the carbon black component is in range from 10: 1 to 1 :10, or from 10: 1 to 1 :9, or from 10: 1 to 1 :8, or from 10:1 to 1 :7, or from 10: 1 to 1 :6, or from 10: 1 to 1 :5, or from 10: 1 to 1 :4, or from 10: 1 to 1 :3, or from 10: 1 to 1 :2, or from 10: 1 to 1 : 1. In a more preferred embodiment, the ratio of graphene component to carbon black component is in range from 9: 1 to 1 : 1, or from 8: 1 to 1 : 1, or from 7: 1 to 1 : 1, or from 6: 1 to 1 : 1. Additional Components in Polyurethane Resin Composition B

[0179] The polyurethane resin composition B may further optionally comprise an additive that includes a chain extender, a cross linker, a catalyst, an antistatic additive, a flame retardant, at least one reaction mixture additives, and at least one reaction mixture filler, or any combination thereof. [0180] In an embodiment, the additives in the polyurethane resin composition B mixture can be selected from surface-active substances, flame retardants, nucleating agents, oxidation stabilizers, lubricants, mold release agents, dyes, pigments, dyes, flame retardants, hindered amine light stabilizers, ultraviolet light absorbers, stabilizers, ultra violet stabilizers, hydroxy stabilizers, plasticizers, epoxy plasticizers, chain regulator, polyethylene wax, antioxidants, defoamers, internal release agents, desiccants, blowing agents and anti-static agents or combinations thereof. Further details regarding additives can be found, for example, in the Kunststoffhandbuch, Volume 7, “Polyurethane” Carl-Hanser-Verlag Munich, 1st edition, 1966 2nd edition, 1983 and 3rd edition, 1993. Suitable amounts of these additives are well known to the person skilled in the art. However, for instance, the additives can be present in amounts up to 20 wt.-% based on the total weight of the polyurethane resin composition.

[0181] In another preferred embodiment, the at least one additional additive includes a catalyst, a chain extender, a flame retardant, a mold release agent, a rheology additive, a defoamer, a friction reducer, a non-sticky agents, an antistatic additive, a surfactant, a cross linker, or any combination thereof.

[0182] In an embodiment, the chain extender has a molecular weight of less than 499 g/mol. In the context of the present invention, the chain extender is understood to mean a compound having at least two functional groups reactive toward isocyanates, for example hydroxyl groups, amino groups or thiol groups, and a molecular weight Mw of less than 499 g/mol. At the same time, in the context of the present invention, the polyol composition is also free of compounds of this kind.

[0183] Preferably, the chain extenders have a molecular weight less than 300 g/mol, or from 10 g/mol to 210 g/mol. Another preferred chain extender has a molecular weight from 50 g/mol to 150 g/mol, or from 50 g/mol to 120 g/mol, or from 60 g/mol to 120 g/mol.

[0184] Suitable chain extenders can be selected from ethylene glycol, 1,2-propanediol, 1,3- propanediol, 1-5 pentanediol, 1,6-hexanediol, 1,10-decanediol, 1,2-dihydroxy cyclohexane, 1,3- dihydroxy cyclohexane, 1,4-dihydroxy cyclohexane, di ethylene glycol, 1,4-butanediol, bis(2- hydroxy-ethyl)hydroquinone, dipropylene glycol, glycerol, diethanolamine, and triethanolamine. Preferably, the chain extender can be selected from 1,2- ethylene glycol, 1,3 -propylene glycol, 1,4 butane diol, 1,5-pentane diol, 1,6-hexane diol, Hydroquinone Bis (2-hydroxy ethyl) Ether (HQEE), or/ and hydroxyethylether of resorcinol or 1,3-Bis (2-hydroxyethyl) resorcinol (HER).

[0185] In one embodiment, suitable chain extenders and/or cross linkers present in the polyurethane resin composition is further described. The addition of bifunctional chain extenders, trifunctional and higher-functional cross linkers or, if appropriate, mixtures thereof might be added. Chain extenders and/or cross linkers used are preferably alkanol amines and in particular diols and/or triols having molecular weights preferably in between 60 g/mol to 300 g/mol. Suitable amounts of these chain extenders and/or cross linkers can be added and are known to the person skilled in the art. For instance, chain extenders and/or cross linkers can be present in an amount up to 99 wt.-%, or up to 20 wt.-%, based on the total weight of the polyurethane resin composition.

[0186] In another embodiment, commercially available compounds that are reactive towards isocyanate can also be employed, for e.g. Sovermol®, Pluracol® and Quadrol® from BASF.

[0187] Suitable catalysts are well known to the person skilled in the art. For instance, tertiary amine and phosphine compounds, metal catalysts such as chelates of various metals, acidic metal salts of strong acids; strong bases, alcoholates and phenolates of various metals, salts of organic acids with a variety of metals, organometallic derivatives of tetravalent tin, trivalent and pentavalent As, Sb and Bi and metal carbonyls of iron and cobalt and mixtures thereof can be used as catalysts.

[0188] Suitable tertiary amines include, such as triethylamine, tributylamine, N- methylmorpholine, N-ethylmorpholine, N,N, N', N'-tetramethylethylenediamine, pentamethyldiethylenetriamine and higher homologues (as described in, for example, DE- A 2,624,527 and 2,624,528), l,4-diazabicyclo(2.2.2)octane, N-methyl-N'-dimethyl-aminoethylpiperazine, bis- (dimethylaminoalkyl)piperazines, tris(dimethylaminopropyl)hexahydro-l,3,5-triazin, N,N- dimethylbenzylamine, N,N-dimethylcyclohexylamine, N,N-diethyl-benzylamine, bis-(N,N- di ethylaminoethyl) adipate, N,N,N',N'-tetram ethyl- 1,3 -butanediamine, N,N-dimethyl-p- phenylethylamine, 1 ,2-dimethylimidazole, 2-methylimidazole, monocyclic and bicyclic amines together with bis-(dialkylamino)alkyl ethers, such as 2,2-bis-(dimethylaminoethyl)ether. Triazine compounds, such as, but not limited to, tris(dimethylaminopropyl)hexahydro-l,3,5-triazin can also be used.

[0189] Suitable catalysts are likewise known in principle from the prior art. Suitable catalysts are, for example, organic metal compounds selected from the group consisting of tin organyls, titanium organyls, zirconium organyls, hafnium organyls, bismuth organyls, zinc organyls, aluminum organyls and iron organyls, for example tin organyl compounds, preferably tin dialkyls such as dimethyltin or diethyltin, or tin organyl compounds of aliphatic carboxylic acids, preferably tin diacetate, tin dilaurate, dibutyltin diacetate, dibutyltin dilaurate, bismuth compounds such as bismuth alkyl compounds or the like, or iron compounds, preferably iron(Ml) acetylacetonate, or the metal salts of the carboxylic acids, for example tin(II) isooctoate, tin dioctoate, titanic esters or bismuth(III) neodecanoate.

[0190] The catalysts, as described hereinabove, can be present in amounts preferably up to 20 wt.-% based on the total weight of the PU composition.

[0191] Suitable fillers include, such as, but not limited to, silicatic minerals, examples being finely ground quartzes, phyllosilicates, such as antigorite, serpentine, hornblendes, amphibols, chrysotile, and talc; metal oxides, such as kaolin, aluminum oxides, aluminium hydroxides, magnesium hydroxides, hydromagnesite, titanium oxides and iron oxides, metal salts such as chalk, heavy spar and inorganic pigments, such as cadmium sulfide, zinc sulfide, and also glass and others. Preference is given to using kaolin (china clay), finely ground quartzes, aluminum silicate, and coprecipitates of barium sulfate and aluminum silicate.

[0192] Suitable fillers have an average particle diameter in the range of 0.1 pm to 500 pm, more preferably in the range of 1 pm to 100 pm, and most preferably in the range of 1 pm to 10 pm. Diameter in this context, in the case of non-spherical particles, refers to their extent along the shortest axis in space.

[0193] Suitable amounts of the fillers can be present in the polyurethane resin composition which are known to the person skilled in the art. For instance, fillers can be present in an amount up to 50 wt.-%, based on the total weight of the polyurethane resin composition B.

[0194] Suitable flame retardants are tetrabromobisphenol A, brominated polystyrene oligomers, brominated butadiene-polystyrene copolymers in accordance with WO 2007/058736, tetrabromobisphenol A diallyl ether, and hexabromocyclododecane (HBCD), in particular the industrial products, where these in essence comprise the a-, P-, and y -isomer with added synergists, such as dicumyl. Preference is given to brominated aromatics, such as tetrabromobisphenol A, and to brominated styrene oligomers. Examples of suitable halogen-free flame retardants are expandable graphite, red phosphorus, and phosphorus compounds, such as triphenyl phosphate and 9,10-dihydro-9-oxa-10-phosphaphenanthrene 10-oxide. [0195] In a preferred embodiment, the flame retardant is graphite. The graphite includes graphite ore treated with sulfuric acid by intercalation process. The graphite ore has bulk density in range of 0.45 to 0.60 g/cm ³ .

[0196] Preferred phosphorus compounds are tris(2-chloroisopropyl) phosphate, triethyl phosphate, diethyl ethylphosphonate, cresyl diphenyl phosphate, Exolit OP560, diphenyl 6- (diphenoxyphosphoryloxy)hexahydrofuro[3,2-b]furan-3-yl phosphate, 9, 10-dihydro-9-oxa-10- phosphaphenanthrene 10-oxide, and 6H-dibenzo[c,e][l,2]oxaphosphorine 6-oxide.

[0197] Preference is moreover given to organic peroxides (dicumyl peroxide), sulfur, and disulfides as synergists. The abovementioned flame retardants can either be dissolved in the monomers before the polymerization reaction starts or incorporated in the polyurethane resin composition B by extrusion.

[0198] Antistatic additives and antistatic polymers are known. By way of example, DE 3531660 describes antistatic polyurethane shoe soles. The antistatic effect is achieved via from 0.01 to 0.3% by weight of chemically bonded sulfonate groups. The volume resistivities achieved are <108 Q/cm. The use of various quaternary ammonium salts for increasing the conductivity of polymers is described in EP 1134268. This involves modifications of commercially available antistatic additives, such as Catafor F® or Catafor PU® from Rhodia. For example, volume resistivities of about 107 Q/cm are achieved at high concentrations.

[0199] Antistatic additives include ethylmethylimidazole ethyl sulfate. Ethylmethylimidazole ethyl sulfate can be used here alone or in a mixture, for example together with other antistatic additives. It is preferable that ethylmethylimidazole ethyl sulfate is used as sole antistatic additive. [0200] In an embodiment, the antistatic additive may be any selected from Soyabean oil with CIO to C16 Carbon chains, l-Ethyl-3 -methyl imidazolium di cyanamide, alkali metal salts in solvent, phosphoric acid and triethyl ether, metallic salt, polyether, and the like or a combination thereof.

[0201] Hydrolysis stabilizers used preferably comprise oligomeric and/or polymeric aliphatic or aromatic carbodiimides.

[0202] In order to stabilize the polyurethane resin composition B, with respect to aging, it is preferable that stabilizers are added to the polyurethane resin composition B. For the purposes of the present invention, stabilizers are additives which protect a plastic or a plastics mixture from damaging environmental effects. Examples are primary and secondary antioxidants, hindered amine light stabilizer, UV absorber, hydrolysis stabilizer, quencher, and flame retardant. Examples of commercial stabilizers are given in Plastics Additive Handbook, 5th Edition, H. Zweifel, ed., Hanser Publishers, Munich, 2001 ([1]), pp. 98-136.

[0203] If the polyurethane resin composition B has exposure to thermoxidative degradation during its use, antioxidants can be added. It is preferable to use phenolic antioxidants. Examples of phenolic antioxidants are given in Plastics Additive Handbook, 5th edition, H. Zweifel, ed, Hanser Publishers, Munich, 2001, pp. 98-107 and pp. 116-121. Preference is given to those phenolic antioxidants whose molar mass is greater than 700 g/mol. An example of a phenolic antioxidant whose use is preferred is pentaerythrityl tetrakis(3-(3,5-bis(l,l-dimethylethyl)-4- hydroxyphenyl)propionate) (Irganox® 1010). The concentrations generally used of the phenolic antioxidants are from 0.1 to 5% by weight, preferably from 0.1 to 2% by weight, in particular from 0.5 to 1.5% by weight, based in each case on the total weight of the polyurethane resin composition B.

[0204] If the polyurethane resin composition B may optionally may include a UV absorber. UV absorbers are molecules which absorb high-energy UV light and dissipate the energy. Familiar UV absorbers used industrially are, for example, members of the group of cinnamic esters, of diphenylcyanoacrylates, of the formamidines, of the benzylidenemalonates, of the diarylbutadienes, or triazines, or of the benzotriazoles. Examples of commercial UV absorbers are found in Plastics Additive Handbook, 5th edition, H. Zweifel, ed, Hanser Publishers, Munich, 2001, pp. 116-122. In one preferred embodiment, the number-average molar mass of the UV absorbers is greater than 300 g/mol, in particular greater than 390 g/mol. The UV absorbers preferably used should moreover have molar mass no greater than 5000 g/mol, particularly preferably no greater than 2000 g/mol. The benzotriazoles group is particularly suitable as UV absorber. Examples of particularly suitable benzotriazoles are Tinuvin® 213, Tinuvin® 328, Tinuvin® 571, and also Tinuvin® 384, and Eversorb®82. The amounts preferably added of the UV absorbers are from 0.01 to 5% by weight, based on the total weight of antistatic, polyurethane, particularly preferably from 0.1 to 2.0% by weight, in particular from 0.2 to 0.5% by weight, based in each case on the total weight of the antistatic polyurethane.

[0205] In a preferred embodiment, the UV absorbers have a number average molecular weight of greater than 0.3xl0 ³ g/mol, in particular greater than 0.39xl0 ³ g/mol. Furthermore, the UV absorbers which are preferably used should have a molecular weight of not greater than 5xl0 ³ g/mol, particularly preferably not greater than 2x10 ³ g/mol. [0206] Particularly suitable UV absorbers are from the group of benzotriazoles. Examples of particularly suitable benzotriazoles are Tinuvin® 213, Tinuvin® 234, Tinuvin® 571 and Tinuvin® 384 and Ever- sorb®82. The UV absorbers are usually added in amounts of from 0.01 to 5% by weight, based on the total mass of the polyurethane resin composition B, preferably 0.1-2.0% by weight, in particular 0.2-0.5% by weight.

[0207] A UV stabilization as described above based on an antioxidant and a UV absorber is often still not sufficient to ensure good stability of the film against the damaging influence of UV rays. In this case, a hindered amine light stabilizer (HALS) can be added in addition to the antioxidant and the UV absorber to the film. HALSs are highly efficient UV stabilizers for most polymers.

[0208] HALS compounds are generally known and commercially available. Examples of commercially available HALSs may be found in Plastics Additive Handbook, 5th edition, H. Zweifel, Hanser Publishers, Munich, 2001, pp. 123-136.

[0209] As hindered amine light stabilizers, preference is given to employing hindered amine light stabilizers in which the number average molecular weight is greater than 500 g/mol. Furthermore, the molecular weight of the preferred HALS compounds should be not greater than 10 000 g/mol, particularly preferably not greater than 5000 g/mol.

[0210] Particularly preferred hindered amine light stabilizers are bis(l , 2, 2,6,6- pentamethylpiperidyl) se- bacate (Tinuvin® 765, Ciba Spezialitatenchemie AG) and the condensation product of 1-hydrox- yethyl-2,2,6,6-tetramethyl-4-hydroxypiperidine and succinic acid (Tinuvin® 622). Particular preference is given to the condensation product of 1 -hydroxy ethyl- 2,2,6,6-tetramethyl-4-hydrox- ypiperidine and succinic acid (Tinuvin® 622) when the titanium content of the product is <150 ppm, preferably <50 ppm, in particular <10 ppm. HALS compounds are preferably used in a concentration of from 0.01 to 5% by weight, particularly preferably from 0.1 to 1% by weight, in particular from 0.15 to 0.3% by weight referring to the total weight of the film.

[0211] In a preferred embodiment of the film, hydrolysis inhibitors are comprised in the polyurethane resin composition B as auxiliaries; preference is given here to oligomeric and/or polymeric aliphatic or aromatic carbodiimides.

[0212] Further details regarding the abovementioned auxiliaries and additives may be found in the specialist literature, for example in Plastics Additive Handbook, 5th edition, H. Zweifel, ed., Hanser Publishers, Munich, 2001. [0213] Mold release agents include release agents based on wax or silicon, mold release agents based on salts of aliphatic mono- or polycarboxylic acids having at least 25 carbon atoms, and primary mono-, di-, or polyamines having two or more carbon atoms, or amide or ester group- containing amines, which have at least one primary, secondary or tertiary amino group, release agents based on mixtures of at least two compounds from the group of amine-carboxylic acidsalts, saturated or unsaturated CeOH- and/or OH group-containing esters from mono- and/or poly carboxylic acids, and multivalent alcohols or natural and/or synthetic oils, fats or waxes, mold release agents based on ketimines, al dimines, enamines or cyclic Schiff bases.

[0214] The friction reducers include polyethylene and polytetrafluoroethylene (PTFE) powders. Polyethylene includes crosslinked and non-crosslinked polyethylene.

[0215] In an embodiment the friction reducer is a non-cross linked polyethylene. In an embodiment, the non-cross linked polyethylene includes high density polyethylene (HDPE), high density and high molecular weight polyethylene (HDPE- HMW), high density and ultrahigh molecular weight polyethylene (HDPE-UHMW), medium density polyethylene (MDPE), low density polyethylene (LDPE), linear low density polyethylene (LLDPE), (VLDPE) and (ULDPE) [0216] In a preferred embodiment the non-crosslinked polyethylene is an Ultra-high molecular weight polyethylene (UHMWPE) powder. In another preferred embodiment, the UHMWPE has d50 average particle size in range from 0.01 pm to 500pm. In a more preferred embodiment the UHMWPE has the average particle size less than from 0.01 pm to 400pm or from 0.01 pm to 300pm, or from 0.01 pm to 200pm or from 0.01 pm to 100pm.

[0217] In another preferred embodiment the molecular weight in range of 0.5 Mio g/ mol to 20 Mio g/ mol. In a more preferred embodiment the UHMWPE has a molecular weight in range of 1.0 Mio g/ mol to 20 Mio g/ mol or in range of 1 Mio g/ mol to 15 Mio g/ mol, or in range of 1.0 Mio g/ mol to 10 Mio g/ mol.

[0218] In another embodiment, the friction reducer is a polytetrafluoroethylene (PTFE) powder.

[0219] In yet another embodiment the friction reducer is in a range from 0.1 to 10.0 wt.% of the polyurethane resin composition B. In a preferred embodiment the friction reducer is in a range from 1.0 to 9.0 wt.% of the polyurethane resin composition B, or from 1.0 to 8.0 wt.%, or from 1.0 to 7.0 wt.%, or from 1.0 to 6.0 wt.%, or from 1.0 to 5.0 wt.%. In a more preferred embodiment, the friction reducer is in range of 1.0 to 5.0 wt.% of the polyurethane resin composition B. [0220] In another preferred embodiment, the at least one friction reducer is selected from UHMWPE and PTFE or combination thereof. In a further embodiment the at least one friction reducer is in range of 0 to 30.0 wt. % of the polyurethane resin composition B.

Methods

[0221] In another aspect, the presently claimed invention is directed to process for preparing a panel construction, said process comprising the steps of (SI) spraying a polyurethane resin composition A onto at least one surface of a mat layer, wherein said polyurethane resin composition A forms a polyurethane film on the at least one surface of the mat layer resulting in a pre-impregnated blank, (S2) compression molding the pre-impregnated blank along with a honeycomb layer to obtain a spray -molded panel, and (S3) placing the spray-molded panel in an injection mold and injecting polyurethane composition B into the mold to the apply a polyurethane barrier layer to the spray-molded panel by reaction injection molding. Preferably, the process includes a spray transfer molding process.

[0222] The polyurethane resin compositions A and B, including the isocyanate, the compounds reactive towards isocyanate, the catalysts, the additives and the fillers that are used in the process according to the present invention are described hereinabove.

[0223] In step (SI), the spraying of the polyurethane resin composition onto the at least one mat layer can be carried out using suitable means well known to the person skilled in the art (refer Ullman’s encylcopedia of industrial chemistry; DOI: 10.1002/14356007). However, the isocyanate component A and the isocyanate reactive component A can be mixed in a mixing device to obtain a reactive mixture before spraying it onto the at least one mat layer as the polyurethane resin composition A to obtain the pre-impregnated blank. Suitable mixing device for this purpose are preferably a mixing head or a static mixer.

[0224] In an exemplary embodiment, the reaction mixture of polyurethane resin composition A is obtained by feeding at least two streams into the mixing device, wherein a first stream comprises at least one isocyanate component A, and a second stream comprises at least one polyol A component, wherein at least two catalysts, and optionally, an additive and/or filler is present in at least one of the first or second streams.

[0225] Suitable temperatures for processing the reaction mixture of polyurethane resin composition A are well known to the person skilled in the art. In a preferred embodiment, the first stream and the second stream, independent of each other, can be pre-mixed in suitable mixing means, such as, a static mixer. [0226] The mixing device can be a low pressure or high-pressure mixing device comprising: [0227] pumps to feed the streams,

[0228] a high-pressure mixing head in which the streams, as described hereinabove, are mixed,

[0229] a first feed line fitted to the high-pressure mixing head through which the first stream is introduced into the mixing head, and

[0230] a second feed line fitted to the high-pressure mixing head through which the second stream is introduced into the mixing head.

[0231] Optionally, the mixing device, as described hereinabove, can further comprise at least one measurement and control unit for establishing the pressures of each feed lines in the mixing head. Also, the term “low pressure” here refers to a pressure of from 0.1 MPa to 5 MPa, while the term “high-pressure” refers to pressure above 5 MPa.

[0232] Preferably, the reaction mixture of polyurethane resin composition A is passed from the mixing head into the mixing device. A solid/gas mixture can be added through additional inlets. By “solid”, it is referred to the fillers, as described hereinabove, which are in a solid state of matter. [0233] The reaction mixture of polyurethane resin composition A obtained from the mixing device is fed to the spraying means. Suitable spraying means include, but are not limited to, spray heads. In a preferred embodiment, the spray head for spraying the polyurethane resin composition comprises at least one polyurethane spray jet. The polyurethane spray jet essentially consists of fine particles or droplets of the polyurethane resin composition, i.e. of the reaction mixture, preferably dispersed in a gas stream. Such a polyurethane spray jet can be obtained in different ways, for example, by atomizing a liquid jet of the reaction mixture of the polyurethane resin composition by a gas stream introduced into it, or by the ejection of a liquid jet of the reaction mixture from a corresponding nozzle or atomizer. By the term “liquid jet of the reaction mixture”, it is referred to the fluid jet of the reaction mixture of the polyurethane resin composition that is not yet in the form of fine reaction mixture droplets dispersed in a gas stream, i.e. especially in a liquid viscous phase. Thus, in particular, such a “liquid jet of the reaction mixture” does not mean a polyurethane spray jet, as described above. Such methods are described, for example in, DE 10 2005 048 874 Al, DE 101 61 600 Al, WO 2007/073825 A2, US 3,107,057 A and DE 1 202 977 B, all incorporated herein by reference.

[0234] Alternatively, a solid containing gas stream can also be employed instead of the gas stream, as described hereinabove. The solid-containing gas stream is preferably prepared by passing the gas stream through solid-containing metering cells of a cellular wheel sluice. By the flushing of the cellular spaces, the solid is dragged along by the pressurized air stream and transported to the mixing head as a solid/air or solid/gas mixture. To avoid pulsation, the channel inside the metering sluice must be designed with a diameter that excludes positive overlap. This embodiment further ensures that a quantitatively unchanged air flow rate for spraying the reaction mixture is available even when the cellular wheel sluice metering is turned off of its revolutions per minute is changed, and thus spraying can be effected alternatively without or with variable filler quantities. As a particular advantage of such a cellular wheel sluice, the solid proportion in the pre-impregnated blank to be prepared can be variably adjusted.

[0235] The polyurethane spray jet, as described hereinabove, impinges on a spray area oscillating with an adjustable amplitude of preferably less than 500 mm. By the term “spray area”, it is referred to the target area of the at least one mat layer.

[0236] During the spraying, as disclosed hereinabove, the at least one mat layer is wetted on preferably both sides with the polyurethane resin composition A, also described hereinabove. It is particularly preferred that the spraying of the polyurethane resin composition A is done on both the sides of the at least one mat layer.

[0237] Handling of the at least one mat layer can be either manually or automatically. By the term “automatically”, it is referred to the handling of the at least one mat layer via a human interface, for instance, using industrial robots. In a preferred embodiment, an industrial robot that has preferably 6 axes and is especially tailored for production facilities using flexible robotcontroller automation is employed. The robot is operated by means of a process software incorporated into a control cabinet. The control is suitable for communicating with external control systems. The robot can be equipped with a highly developed dual port safety system, the functions of which are continuously monitored. In case of a failure or malfunction, the electric supply of the motors can be switched off and brakes activated. Furthermore, the movement of each axes can be limited by software functions. In a preferred embodiment, the robot is driven via brushless three phase servomotors with brakes on all axes.

[0238] The pre-impregnated blank obtained in step (SI) is subsequently compression molded in step (S2), for example, in a heated compression molding tool and is compressed in accordance with the required panel construction geometry and hardened to obtain a spray-molded panel. Subsequently, it is optionally possible, while the spray-molded panel construction is left in the compression molding tool, for a contour cut, that is to say, coarse cutting to shape, to be performed around the tool or around the tool geometry. [0239] Preferably, it is also possible, if necessary, for the spray-molded panel construction to be cooled or thermally stabilized in the compression molding tool or outside the compression molding tool, more preferably cooled or thermally stabilized in a further tool, in particular in a workpiece cooling device.

[0240] In accordance with the embodiments, “thermally stabilized” is to be understood to mean that the panel construction assumes a temperature below the previous conversion temperature in order to attain a stable state. Here, the cooling in a workpiece cooling device makes it possible to realize the shortest production time, in particular with regard to continuous production of only one spray-molded panel construction.

[0241] Preferably, tempering of the spay-molded panel construction, that is to say a temperature process, in order for distortions to be compensated and/or the level of cross-linking of the materials to be increased, is performed in a further tool or in a further device. For example, it may be provided that, for cooling, the panel construction is merely placed on a frame or by way of one side on a surface. Use may however also be made of a closed cooling device which surrounds the panel construction around the full circumference and in which the temperature can be regulated. Further cooling of the panel construction can optionally be performed.

[0242] Preferably, the cooling can be followed by trimming of the outer contour, or cutting to shape of the side regions/edges, in accordance with the required panel construction contour and optionally also a chip-removing machining process, such as, for example, milling of the outer contour and milling and drilling for inserts and other similar recesses in the panel construction.

[0243] In (S3), the spray-molded panel is placed in an injection mold and injecting polyurethane composition B into the mold to the apply a polyurethane barrier layer to the spray- molded panel by reaction injection molding.

[0244] The polyurethane resin composition B may be obtained by providing the isocyanate component B and the isocyanate reactive component B of the reaction mixture; mixing the components and optionally heating the reaction mixture. In an embodiment, the mixing of polyurethane composition B is performed by a mixing device. The mixing device and conditions may have be similar to those used to prepare the polyurethane resin composition A. Suitable temperatures for processing the reaction mixture of polyurethane composition B are well known to the person skilled in the art. In an embodiment the mixing is performed at a temperature from 40°C to 85°C. [0245] In one embodiment, before mixing into the mixing device, the isocyanate component B and the isocyanate reactive component B, independent of each other, are pre-mixed in suitable mixing means, such as, but not limited to, a static mixer. In an embodiment, the method of obtaining the polyurethane resin composition B includes premixing the isocyanate reactive component B (having the graphene and CB) with high shear force before mixing with the isocyanate component B.

[0246] In step (S3), an overmolded polyurethane barrier layer comprising the polyurethane resin composition B is applied to the spray -molded panel by a reaction injection molding (RIM) process. RIM is a subset of injection molding that creates parts typically by using impingement mixing of reactive liquid intermediates as they enter a mold. Here, the reactive liquid intermediates include the polyurethane resin composition B, along with any catalysts, additives and fillers as described above. In RIM, the isocyanate component and isocyanate-reactive components react in the mold and undergo cross-linking or polymerization.

[0247] The basic elements of a RIM molding system include a conditioning system that prepares the liquid intermediates for use, a metered pumping system that ensures delivery of the intermediates in appropriate quantity and pressure, one or more high-pressure mixing heads where the liquid intermediates are combined through impingement, and a mold carrier that orients the mold as required and opens and closes it for cleaning and demolding.

[0248] To apply the overmolded polyurethane barrier layer to the spray-molded panel by a RIM process, the spray-molded panel is placed in a RIM mold and the mold is then closed and sealed. An isocyanate component B and an isocyanate-reactive component B of polyurethane resin composition B may be pumped through respective metered pumping systems to one or more high-pressure mixing heads where the liquid intermediates are combined through impingement, then the mixture is injected into the closed mold. Once the RIM process is complete, typically within a few minutes, the mold is opened and the RIM panel construction is demolded.

[0249] Typically, in the RIM step, the reactive liquid intermediates are selected to have a low viscosity during mold filling. Consequently, molding pressures in RIM can range from 50 bar to 1000 bar, more preferably from 100 bar to 500 bar, 150 bar to 300 bar.

[0250] The temperature of the mold during the RIM process may generally be under 150°C. Suitable mold temperatures may be 125°C or less, 100°C or less, or 85°C or less. In another embodiment, the reaction mixture of polyurethane resin composition B is injected into a mold and cured at temperature between 60°C to 85°C. In another embodiment, the mold temperature is 60°C, with fill time of 5 to 20 seconds and demold time in range of 1 to 15 mins.

[0251] The composition according to the presently claimed invention has at least one of the following advantages:

[0252] 1. The isocyanate-reactive composition A has low viscosity (< 2000 cps at 23C) and high lubricating ability.

[0253] 2. The isocyanate-reactive composition A may include a high castor oil content that results in the composition being less toxic and environmentally benign.

[0254] 3. The polyurethane resin composition A has a high adhesion/bonding with thermoplastics and ensures greater wettability of mat layer.

[0255] 4. The polyurethane resin composition A is adaptable to spray molding techniques.

[0256] 5. The overmolded barrier layer of polyurethane resin composition B has a high adhesion/bonding with the mat layer to resist delamination.

[0257] 6. The overmolded barrier layer of polyurethane resin composition B provides a smooth surface with a low coefficient of friction to facilitate passive movement of parcels.

[0258] 7. The parcel panel constructions and chute segments made therefrom have a superior balance of high strength and low weight than is available in conventional materials.