TECHNICAL FIELD

[0001] The present disclosure relates to production of copolyesters and copolyester fibers.

BACKGROUND

[0002] Textile fibers for garments may be produced from many different sources, ranging from animals and plants, as well as synthetic methods to produce various polymers and polymer- based materials.

[0003] There is a need in the art for commercially viable methods and systems to produce copolyester fibers, including bio-based copolyester fibers. Further, there is a need in the art for methods and systems to produce copolyester products, such as bio-based copolyester products, including bio-based copolyester films and molded articles.

SUMMARY

[0004] In an example, the present disclosure provides a segmented copolyester ether resin, including a polyester block covalently bonded to a poly ether block. The copolyester ether resin is formed by esterification and polycondensation reactions including an aromatic or aliphatic dicarboxylic acid, a glycol, and a polyethylene glycol (“PEG”) oligomer. The PEG oligomer has a molecular weight of at least 500 g/mol.

[0005] In another example, the present disclosure provides a segmented copolyester ether resin of formula (II):

(GiAi)x(PEG)z(GiA ₂ ) _y (II).

Ai is an aromatic or aliphatic dicarboxylic acid. A ₂ is an aromatic or aliphatic dicarboxylic acid. Gi is a glycol. (GiAi) and (GIA ₂ ) are each polyester blocks. PEG is a polyethylene glycol oligomer including a terminal group capable of covalently bonding to hydroxyl groups and/or a terminal group capable of covalently bonding to terminal carboxylic acid groups, the polyethylene glycol oligomer having a molecular weight of at least 500 g/mol; x > 1, y > 1, and z > 1.

[0006] In yet another example, the present disclosure provides a bicomponent fiber, including a core including a polyethylene glycol (“PEG”) oligomer of a molecular weight of at least 500 g/mol; and a sheath outer layer including a thermoplastic, the sheath outer layer encapsulating the core. [0007] Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

DRAWINGS

[0008] In order that the present disclosure may be well understood, there will now be described various forms thereof, given by way of example, reference being made to the accompanying drawings. The components in the figures are not necessarily to scale. Moreover, in the figures, like-referenced numerals designate corresponding parts through the different views.

[0009] FIG. 1 illustrates a conventional differential scanning calorimetry (“DSC”) scan of a first run for an example of a PETF10-PEG2000 copolyester ether resin pellet, prepared according to the principles of the present disclosure;

[0010] FIG. 2 illustrates a DSC scan of a second run for an example of an example of a PETF10-PEG2000 copolyester ether resin pellet, prepared according to the principles of the present disclosure;

[0011] FIG. 3 illustrates a DSC scan of a first run for an example of a PETF10-PEG2000 copolyester ether resin filament, prepared according to the principles of the present disclosure; [0012] FIG. 4 illustrates a DSC scan of a second run for an example of a PETF10-PEG2000 copolyester ether resin filament, prepared according to the principles of the present disclosure; [0013] FIG. 5 illustrates a DSC scan of a first run for an example of a PETF10-PEG4000 copolyester ether resin pellet, prepared according to the principles of the present disclosure;

[0014] FIG. 6 illustrates a DSC scan of a second run for an example of a PETF10-PEG4000 copolyester ether resin pellet, prepared according to the principles of the present disclosure;

[0015] FIG. 7 illustrates a DSC scan of a first run for an example of a PETF10-PEG4000 copolyester ether resin filament, prepared according to the principles of the present disclosure; [0016] FIG. 8 illustrates a DSC scan of a second run for an example of a PETF10-PEG4000 copolyester ether resin filament, prepared according to the principles of the present disclosure; [0017] FIG. 9 depicts a plot illustrating copolyester glass transition (T _g ) and peak melting (Tm,2) temperatures, as a function of PEG segment nominal molecular weight, of examples of copolyester ether resins prepared according to the principles of the present disclosure;

[0018] FIG. 10 depicts a plot illustrating crystallization or melting enthalpy of polyethylene glycols (“PEGs”) of various molecular weights as a function of crystallization or melting temperature; [0019] FIG. 11 depicts a plot illustrating PEG melting enthalpies and crystallization enthalpies of PEGs of various molecular weights; and

[0020] FIG. 12 depicts a plot illustrating PEG peak melting temperatures and PEG peak crystallization temperatures.

[0021] The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.

DETAILED DESCRIPTION

[0022] The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference to numerals indicate like or corresponding parts and features.

[0023] In an example, the present disclosure provides copolyester ether compositions that are made from a dicarboxylic acid and an alkylene glycol.

[0024] Examples of dicarboxylic acids may include 2,5-furandicarboxylic acid (“FDCA,” or “furanoic acid”):

2,5-furandicarboxylic acid ("FDCA").

[0025] Examples of alkylene glycols may include monoethylene glycol (“or ethylene glycol”), trimethylene glycol (or “1,3 -propanediol”), or a polyalkylene glycol, which may be a poly ether that is polymerized from any glycol disclosed herein. Examples of polyalkylene glycols may include polyethylene glycol (“PEG”). The structures of monoethylene glycol, trimethylene glycol, and polyethylene glycol are: monoethylene glycol;

HO^^OH trimethylene glycol; polyethylene glycol ("PEG").

[0026] In certain examples, one or more, or all, of the dicarboxylic acid and alkylene glycol are bio-based. As used herein, the term “bio-based” refers to a compound having been prepared from raw materials that are derived from biomass, such as carbohydrates. Bio-based materials may also be referred to by terms including “bio-materials,” “biosourced materials,” “biosourced materials,” “biobased materials,” or “renewable materials.” The prefixes “bio” and “bio-“ may be used interchangeably.

[0027] In certain examples, bio-based components may make up at least about 5% of the copolyester ether resin, including, for example, at least about 7.5%, or at least about 10%, or at least about 12.5%, or at least about 15%, or at least about 17.5%, or at least about 20%, or at least about 22.5%, or at least about 25%, or at least about 27.5%, or at least about 30%, or at least about 32.5%, or at least about 35%, or at least about 37.5%, or at least about 40%, or at least about 42.5%, or at least about 45%, or at least about 47.5%, or at least about 50%, or at least about 52.5%, or at least about 55%, or at least about 57.5%, or at least about 60%, or at least about 62.5%, or at least about 65%, or at least about 67.5%, or at least about 70%, or at least about 72.5%, or at least about 75%, or at least about 77.5%, or at least about 80%, or at least about 82.5%, or at least about 85%, or at least about 87.5%, or at least about 90%, or at least about 92.5%, or at least about 95%, or at least about 97.5%. Examples of bio-based components may be an aliphatic or aromatic dicarboxylic acid, a glycol, and/or alkylene glycol. [0028] In an example, a homo- or copolyester may include a polyethylene glycol segment that may undergo crystalline-amorphous phase change within a certain temperature window. In certain examples, the homo- or copolyester may be bio-based. In certain examples, the homo- or copolyester may include a polyalkylene glycol segment. In certain examples, the molecular weight of the polyalkylene glycol segment may be greater than about 500 g/mol.

[0029] In an example, the present disclosure provides a copolyester ether resin. In certain examples, the copolyester ether resin may be a segmented polymer including a polyester block covalently with a polyalkylene glycol oligomer block formed through the esterification and polycondensation reactions of at least one aromatic or aliphatic dicarboxylic acid (such as Ai, A2, A3), a glycol (such as Gi, G2 G3), and a polyethylene glycol (PEG) oligomer having a molecular weight of at least about 500 g/mol. In certain examples, the at least one aromatic or aliphatic dicarboxylic acid may be bio-based. Examples of the at least one aromatic or aliphatic dicarboxylic acid may include FDCA, terephthalic acid (“TP A”), and azelaic acid (“AzA”), the structures of TPA and AzA shown below: azelaic acid ("AzA").

In certain examples, the glycol may be bio-based. Examples of the glycol may include C2 - C12 linear and cyclic aliphatic diols having a functionality of two, such as ethylene glycol, trimethylene glycol, 1,4-butanediol, 1,4-cyclohexanedimethanol (“CHDM”), and 2,5- bis(hydroxymethyl)furan, the structures of 1,4-butanediol, CHDM, and 2,5- bis(hydroxymethyl)furan shown below:

1,4-butanediol;

1 ,4-cyclohexanedimethanol ("CHDM");

2,5-bis(hydroxymethyl)furan.

A polyalkylene glycol may be pre-polymerized from any example of a glycol disclosed herein. [0030] As used herein, the term “functionality” refers to the number of polymerizable groups of a monomer.

[0031] In certain examples, the PEG oligomer may account for not more than about 70 weight percent of the copolyester ether resin, and may vary from about 1 weight percent to about 70 weight percent of the copolyester ether resin, including, for example, from about 2 weight percent, or from about 4 weight percent, or from about 6 weight percent, or from about 8 weight percent, or from about 10 weight percent, or from about 12 weight percent, or from about 14 weight percent, or from about 16 weight percent, or from about 18 weight percent, or from about 20 weight percent, or from about 22 weight percent, or from about 24 weight percent, or from about 26 weight percent, or from about 28 weight percent, or from about 30 weight percent, or from about 32 weight percent, or from about 34 weight percent, or from about 36 weight percent, or from about 38 weight percent, or from about 40 weight percent, or from about 42 weight percent, or from about 44 weight percent, or from about 46 weight percent, or from about 48 weight percent, or from about 50 weight percent, or from about 52 weight percent, or from about 54 weight percent, or from about 56 weight percent, or from about 58 weight percent, or from about 60 weight percent, or from about 62 weight percent, or from about 64 weight percent, or from about 66 weight percent, or from about 68 percent to about 70 weight percent; or from about 1 weight percent to about 2 weight percent, or to about 4 weight percent, or to about 6 weight percent, or to about 8 weight percent, or to about 10 weight percent, or to about 12 weight percent, or to about 14 weight percent, or to about 16 weight percent, or to about 18 weight percent, or to about 20 weight percent, or to about 22 weight percent, or to about 24 weight percent, or to about 26 weight percent, or to about 28 weight percent, or to about 30 weight percent, or to about 32 weight percent, or to about 34 weight percent, or to about 36 weight percent, or to about 38 weight percent, or to about 40 weight percent, or to about 42 weight percent, or to about 44 weight percent, or to about 46 weight percent, or to about 48 weight percent, or to about 50 weight percent, or to about 52 weight percent, or to about 54 weight percent, or to about 56 weight percent, or to about 58 weight percent, or to about 60 weight percent, or to about 62 weight percent, or to about 64 weight percent, or to about 66 weight percent, or to about 68 weight percent, or to about 70 weight percent; or any range formed from any two of the foregoing weight percentages; including any sub-ranges therebetween.

[0032] In certain examples, the PEG oligomer may have a molecular weight of from about 1000 g/mol to about 10500 g/mol, including, for example, from about 1100 g/mol, or from about 1200 g/mol, or from about 1300 g/mol, or from about 1400 g/mol, or from about 1500 g/mol, or from about 1600 g/mol, or from about 1700 g/mol, or from about 1800 g/mol, or from about 1900 g/mol, or from about 2000 g/mol, or from about 2100 g/mol, or from about 2200 g/mol, or from about 2300 g/mol, or from about 2400 g/mol, or from about 2500 g/mol, or from about 2600 g/mol, or from about 2700 g/mol, or from about 2800 g/mol, or from about 2900 g/mol, or from about 3000 g/mol, or from about 3100 g/mol, or from about 3200 g/mol, or from about 3300 g/mol, or from about 3400 g/mol, or from about 3500 g/mol, or from about 3600 g/mol, or from about 3700 g/mol, or from about 3800 g/mol, or from about 3900 g/mol, or from about 4000 g/mol, or from about 4100 g/mol, or from about 4200 g/mol, or from about 4300 g/mol, or from about 4400 g/mol, or from about 4500 g/mol, or from about 4600 g/mol, or from about 4700 g/mol, or from about 4800 g/mol, or from about 4900 g/mol, or from about 5000 g/mol, or from about 5100 g/mol, or from about 5200 g/mol, or from about 5300 g/mol, or from about 5400 g/mol, or from about 5500 g/mol, or from about 5600 g/mol, or from about 5700 g/mol, or from about 5800 g/mol, or from about 5900 g/mol, or from about 6000 g/mol, or from about 6100 g/mol, or from about 6200 g/mol, or from about 6300 g/mol, or from about 6400 g/mol, or from about 6500 g/mol, or from about 6600 g/mol, or from about 6700 g/mol, or from about 6800 g/mol, or from about 6900 g/mol, or from about 7000 g/mol, or from about 7100 g/mol, or from about 7200 g/mol, or from about 7300 g/mol, or from about 7400 g/mol, or from about 7500 g/mol, or from about 7600 g/mol, or from about 7700 g/mol, or from about 7800 g/mol, or from about 7900 g/mol, or from about 8000 g/mol, or from about 8100 g/mol, or from about 8200 g/mol, or from about 8300 g/mol, or from about 8400 g/mol, or from about 8500 g/mol, or from about 8600 g/mol, or from about 8700 g/mol, or from about 8800 g/mol, or from about 8900 g/mol, or from about 9000 g/mol, or from about 9100 g/mol, or from about 9200 g/mol, or from about 9300 g/mol, or from about 9400 g/mol, or from about 9500 g/mol, or from about 9600 g/mol, or from about 9700 g/mol, or from about 9800 g/mol, or from about 9900 g/mol, or from about 10000 g/mol, or from about 10100 g/mol, or from about 10200 g/mol, or from about 10300 g/mol, or from about 10400 g/mol to about 10500 g/mol; or from about 1000 g/mol to about 1100 g/mol, or to about 1200 g/mol, or to about 1300 g/mol, or to about 1400 g/mol, or to about 1500 g/mol, or to about 1600 g/mol, or to about 1700 g/mol, or to about 1800 g/mol, or to about 1900 g/mol, or to about 2000 g/mol, or to about 2100 g/mol, or to about 2200 g/mol, or to about 2300 g/mol, or to about 2400 g/mol, or to about 2500 g/mol, or to about 2600 g/mol, or to about 2700 g/mol, or to about 2800 g/mol, or to about 2900 g/mol, or to about 3000 g/mol, or to about 3100 g/mol, or to about 3200 g/mol, or to about 3300 g/mol, or to about 3400 g/mol, or to about 3500 g/mol, or to about 3600 g/mol, or to about 3700 g/mol, or to about 3800 g/mol, or to about 3900 g/mol, or to about 4000 g/mol, or to about 4100 g/mol, or to about 4200 g/mol, or to about 4300 g/mol, or to about 4400 g/mol, or to about 4500 g/mol, or to about 4600 g/mol, or to about 4700 g/mol, or to about 4800 g/mol, or to about 4900 g/mol, or to about 5000 g/mol, or to about 5100 g/mol, or to about 5200 g/mol, or to about 5300 g/mol, or to about 5400 g/mol, or to about 5500 g/mol, or to about 5600 g/mol, or to about 5700 g/mol, or to about 5800 g/mol, or to about 5900 g/mol, or to about 6000 g/mol, or to about 6100 g/mol, or to about 6200 g/mol, or to about 6300 g/mol, or to about 6400 g/mol, or to about 6500 g/mol, or to about 6600 g/mol, or to about 6700 g/mol, or to about 6800 g/mol, or to about 6900 g/mol, or to about 7000 g/mol, or to about 7100 g/mol, or to about 7200 g/mol, or to about 7300 g/mol, or to about 7400 g/mol, or to about 7500 g/mol, or to about 7600 g/mol, or to about 7700 g/mol, or to about 7800 g/mol, or to about 7900 g/mol, or to about 8000 g/mol, or to about 8100 g/mol, or to about 8200 g/mol, or to about 8300 g/mol, or to about 8400 g/mol, or to about 8500 g/mol, or to about 8600 g/mol, or to about 8700 g/mol, or to about 8800 g/mol, or to about 8900 g/mol, or to about 9000 g/mol, or to about 9100 g/mol, or to about 9200 g/mol, or to about 9300 g/mol, or to about 9400 g/mol, or to about 9500 g/mol, or to abut 9600 g/mol, or to about 9700 g/mol, or to about 9800 g/mol, or to about 9900 g/mol, or to about 10000 g/mol, or to about 10100 g/mol, or to about 10200 g/mol, or to about 10300 g/mol, or to about 10400 g/mol, or to about 10500 g/mol; or a range formed from any two of the foregoing molar masses; including any sub-ranges therebetween. The molecular weight of the PEG oligomer may exhibit an endotherm (melting) or exotherm (crystallization) phase change within a narrow temperature range. The prescribed location of the temperature window may be specified relative to an intended application of the copolyester ether resin and a thermal operating environment.

[0033] In certain examples, the PEG oligomer may include terminal functional groups other than hydroxyl groups (“-OH”). The terminal functional groups of the PEG oligomer may be any chemical functional group capable of covalently bonding with a terminal hydroxyl group (for example, a terminal hydroxyl group of a polyester) or capable of covalently bonding with a terminal carboxylic acid group (for example, a terminal carboxylic acid group of a polyester). The PEG oligomer may be homobifunctional, in which the two terminal functional groups are identical, or heterobifunctional, in which the two terminal functional groups are different. Each terminal functional group of a PEG oligomer may independently be a hydroxy, an amino (“- NH2”), a carboxylic acid group, or an isocyanate group (“-N=C=O”). Examples of homobifunctional PEG oligomers available from Millipore Sigma may include: a,<n-Bis{2-[(3-carboxy-l-oxopropyl)amino]ethyl}polyethyle ne glycol;

Poly(ethylene glycol) bis(carboxymethyl) ether;

Poly(ethylene glycol) bis(amine). Regardless of the specific bifunctionality of the PEG oligomer, the covalently bonded PEG oligomer may be capable of phase change activity within a particular temperature range. However, particular bifunctionalities of a PEG oligomer may provide additional benefits, such as a particular hydrolytic stability.

[0034] In certain examples, the copolyester block segment of the copolyester ether resin may fully encapsulate the PEG segment as the major phase of the copolyester ether resin. In certain examples, the copolyester block segment of the copolyester ether resin may vary from about 30 weight percent to about 99 weight percent of the copolyester ether resin, including, for example, from about 32 weight percent, or from about 34 weight percent, or from about 36 weight percent, or from about 38 weight percent, or from about 40 weight percent, or from about 42 weight percent, or from about 44 weight percent, or from about 46 weight percent, or from about 48 weight percent, or from about 50 weight percent, or from about 52 weight percent, or from about 54 weight percent, or from about 56 weight percent, or from about 58 weight percent, or from about 60 weight percent, or from about 62 weight percent, or from about 64 weight percent, or from about 66 weight percent, or from about 68 weight percent, or from about 70 weight percent, or from about 72 weight percent, or from about 74 weight percent, or from about 76 weight percent, or from about 78 weight percent, or from about 80 weight percent, or from about 82 weight percent, or from about 84 weight percent, or from about 86 weight percent, or from about 88 weight percent, or from about 90 weight percent, or from about 92 weight percent, or from about 94 weight percent, or from about 96 weight percent, or from about 98 weight percent to about 99 weight percent; or from about 30 weight percent to about 32 weight percent, or to about 34 weight percent, or to about 36 weight percent, or to about 38 weight percent, or to about 40 weight percent, or to about 42 weight percent, or to about 44 weight percent, or to about 46 weight percent, or to about 48 weight percent, or to about 50 weight percent, or to about 52 weight percent, or to about 54 weight percent, or to about 56 weight percent, or to about 58 weight percent, or to about 60 weight percent, or to about 62 weight percent, or to about 64 weight percent, or to about 66 weight percent, or to about 68 weight percent, or to about 70 weight percent, or to about 72 weight percent, or to about 74 weight percent, or to about 76 weight percent, or to about 78 weight percent, or to about 80 weight percent, or to about 82 weight percent, or to about 84 weight percent, or to about 86 weight percent, or to about 88 weight percent, or to about 90 weight percent, or to about 92 weight percent, or to about 94 weight percent, or to about 96 weight percent, or to about 98 weight percent, or to about 99 weight percent; or any range formed from any two of the foregoing weight percentages; including any sub-ranges therebetween.

[0035] In certain examples, a copolyester ether resin may have an intrinsic viscosity of from about 0.50 dL/g to about 1.50 dL/g, including, for example, from about 0.55 dL/g, or from about 0.60 dL/g, or from about 0.65 dL/g, or from about 0.70 dL/g, or from about 0.75 dL/g, or from about 0.80 dL/g, or from about 0.85 dL/g, or from about 0.90 dL/g, or from about 0.95 dL/g, or from about 1.00 dL/g, or from about 1.05 dL/g, or from about 1.10 dL/g, or from about 1.15 dL/g, or from about 1.20 dL/g, or from about 1.25 dL/g, or from about 1.30 dL/g, or from about 1.35 dL/g, or from about 1.40 dL/g, or from about 1.45 dL/g to about 1.50 dL/g; or from about 0.50 dL/g to about 0.55 dL/g, or to about 0.60 dL/g, or to about 0.65 dL/g, or to about 0.70 dL/g, or to about 0.75 dL/g, or to about 0.80 dL/g, or to about 0.85 dL/g, or to about 0.90 dL/g, or to about 0.95 dL/g, or to about 1.00 dL/g, or to about 1.05 dL/g, or to about 1.10 dL/g, or to about 1.15 dL/g, or to about 1.20 dL/g, or to about 1.25 dL/g, or to about 1.30 dL/g, or to about 1.35 dL/g, or to about 1.40 dL/g, or to about 1.45 dL/g; or a range formed from any two of the foregoing intrinsic viscosities; including any sub-ranges therebetween.

[0036] In certain examples, a polyethylene glycol segment of a copolyester ether resin may exhibit a crystalline phase transition upon cooling or a melting phase transition upon heating within a temperature range of from about -50°C to about 60°C, including, for example, from about -45°C, or from about -40°C, or from about -35°C, or from about -30°C, or from about -25°C, or from about -20°C, or from about -15°C, or from about -10°C, or from about -5°C, or from about 0°C, or from about 5°C, or from about 10°C, or from about 15°C, or from about 20°C, or from about 25°C, or from about 30°C, or from about 35°C, or from about 40°C, or from about 45°C, or from about 50°C, or from about 55°C to about 60°C; or from about -50°C to about -45°C, or to about -40°C, or to about -35°C, or to about -30°C, or to about -25°C, or to about -20°C, or to about -15°C, or to about -10°C, or to about -5°C, or to about 0°C, or to about 5°C, or to about 10°C, or to about 15°C, or to about 20°C, or to about 25°C, or to about 30°C, or to about 35°C, or to about 40°C, or to about 45°C, or to about 50°C, or to about 55°C; or a range formed from any two of the foregoing temperatures; including any subranges therebetween.

[0037] In certain examples, one or more dicarboxylic acids, and one or more glycols, may be specified to produce a desired film, fiber, or molded article with particular physical properties. Examples of physical properties may include glass transition temperature, crystallinity, penetrant diffusion rate, stiffness, breaking strength, and impact toughness. [0038] In an example, the present disclosure provides a bicomponent fiber, including a PEG core within a thermoplastic resin sheath, the sheath serving as an outer protective layer. The bicomponent fiber encapsulating a PEG core may exhibit measurable and useful levels of heat uptake or liberation in endotherm (melting) or exotherm (crystallization) phase change events. The thermoplastic resin may include a polyester, a copolyester, a polyamide, a polyurethane, a nylon, a polycarbonate, or any combination thereof. Material forming the outer sheath may be chosen to efficiently limit the ingress of moisture or oxygen that would facilitate oxidative attack of the PEG core, manifesting in chain scission, degradation, and hydroperoxide generation within the PEG core. A suitable antioxidant package compounded into the PEG core may be needed to provide long-term oxidative stability to the PEG core. A bicomponent filament may also include a sheath that incorporates a PEG pre-polymer to impart greater chain flexibility and fiber elasticity and elongation, while enhancing crystallinity development in the polyester or polyamide sheath resin.

[0039] In certain examples, a bicomponent fiber may include a weight percent of a sheath outer layer of from about 25 weight percent to about 75 weight percent relative to 100 weight percent of the bicomponent fiber, including, for example, from about 30 weight percent, or from about 35 weight percent, or from about 40 weight percent, or from about 45 weight percent, or from about 50 weight percent, or from about 55 weight percent, or from about 60 weight percent, or from about 65 weight percent, or from about 70 weight percent to about 75 weight percent; or from about 25 weight percent to about 30 weight percent, or to about 35 weight percent, or to about 40 weight percent, or to about 45 weight percent, or to about 50 weight percent, or to about 55 weight percent, or to about 60 weight percent, or to about 65 weight percent, or to about 70 weight percent, or to about 75 weight percent; or a range formed from any two of the foregoing weight percentages; including any subranges therebetween.

[0040] In certain examples, the approximate balance of the weight percent of a component fiber with the sheath outer layer is a weight percent of a PEG core of from about 25 weight percent to about 75 weight percent relative to 100 weight percent of the bicomponent fiber, including, for example, from about 30 weight percent, or from about 35 weight percent, or from about 40 weight percent, or from about 45 weight percent, or from about 50 weight percent, or from about 55 weight percent, or from about 60 weight percent, or from about 65 weight percent, or from about 70 weight percent to about 75 weight percent; or from about 25 weight percent to about 30 weight percent, or to about 35 weight percent, or to about 40 weight percent, or to about 45 weight percent, or to about 50 weight percent, or to about 55 weight percent, or to about 60 weight percent, or to about 65 weight percent, or to about 70 weight percent, or to about 75 weight percent; or a range formed from any two of the foregoing weight percentages; including any subranges therebetween.

[0041] In certain examples, the bicomponent fiber may have a circular, elliptical, prismatic, polyhedral, multilobed, or other cross-section. The cross-section may be of any shape provided the sheath outer layer continuously encapsulates the polyether core so as to protect the polyether core from moisture and oxidative attack. Ideal thermoplastics for the sheath outer layer are those polymers that exhibit good melt spinnability and provide low oxygen permeability.

[0042] In certain examples, a PEG core of a certain molecular weight is selected relative to an intended endotherm/exotherm operating range for an application. For example, an ambient apparel application may be intended to operate in a thermal window of 20°C to 30°C. A PEG core of a molecular weight of from about 600 g/mol to about 1000 g/mol, such as 800 g/mol, may satisfy the application phase change requirements and yield an enthalpic gain/release of about 140 J/g of PEG, as illustrated in Table 4 below. The PEG crystallization (subcooling) temperature is about 9°C to about 11°C below the melting temperature. In warmer environments, such as may be needed for warfighter protection and comfort in a desert environment operating at 35°C to 45°C, a higher molecular weight PEG may be needed in a PEG core. A PEG core having a molecular weigh of from about 5500 g/mol to about 6000 g/mol, such as 6000 g/mol, may yield a phase change enthalpy exchange of about 175 J/g PEG within the application temperature range. The PEG crystallization (supercooling) temperature may be about 20°C below the melting temperature.

[0043] In forming PEG-encapsulated bicomponent fibers, methods known to those skilled in the art may be used to pulse dose PEG in the core layer. The PEG may be suitably pigmented or dyed with an inorganic or organic dye for visual and/or spectroscopic detection to register staple fiber cutting processes. Inorganic pigments may also enhance nucleation/crystallization activity in addition to providing a visual and/or spectroscopic cue for actuation of fiber cutting. [0044] In an example, the present disclosure provides a segmented copolyester ether resin, including: a polyester block covalently bonded to a polyether block; wherein the copolyester ether resin is formed by esterification and polycondensation reactions including an aromatic or aliphatic dicarboxylic acid, a glycol, and a polyethylene glycol (“PEG”) oligomer; and wherein the PEG oligomer has a molecular weight of at least 500 g/mol. [0045] In certain examples, the PEG oligomer may have a molecular weight of at least 2000 g/mol.

[0046] In certain examples, the PEG oligomer may have a molecular weight of at least 4000 g/mol.

[0047] In certain examples, the aromatic or aliphatic dicarboxylic acid may include 2,5- furandicarboxylic acid, terephthalic acid, and/or azelaic acid.

[0048] In certain examples, the aromatic or aliphatic dicarboxylic acid may be at least partially bio-based.

[0049] In certain examples, the glycol may be a C2 to C12 linear or cyclic aliphatic diol having a functionality of two.

[0050] In certain examples, the glycol may include ethylene glycol, trimethylene glycol, 1,4- butanediol, 1,4-cyclohexanedimethanol (“CHDM”), and/or 2, 5-bis(hydroxylmethyl)furan.

[0051] In certain examples, the glycol may be at least partially bio-based.

[0052] In certain examples, the resin may include from about 1 weight % to about 70 weight % of the PEG oligomer.

[0053] In certain examples, the resin may include not more than about 60 weight % of the PEG oligomer.

[0054] In certain examples, the resin may include from about 10 weight % to about 50 weight % of the PEG oligomer.

[0055] In certain examples, the resin may include from about 30 weight % to about 99 weight % of the polyester block.

[0056] In certain examples, the resin may include at least 5% bio-based components.

[0057] In an example, a segmented copolyester ether resin of formula (II): (GiAi)x(PEG)z(GiA ₂ ) _y (II), wherein: Ai is an aromatic or aliphatic dicarboxylic acid; A2 is an aromatic or aliphatic dicarboxylic acid; Gi is a glycol; (G1A1) and (G1A2) are each polyester blocks; PEG is a polyethylene glycol oligomer including a terminal group capable of covalently bonding to hydroxyl groups and/or a terminal group capable of covalently bonding to terminal carboxylic acid groups, the polyethylene glycol oligomer having a molecular weight of at least 500 g/mol; x > 1; y > 1; z > 1.

[0058] In certain examples, the polyethylene glycol oligomer may have a molecular weight of at least 2000 g/mol. [0059] In certain examples, the polyethylene glycol oligomer may have a molecular weight of at least 4000 g/mol.

[0060] In certain examples, Ai and A2 may each be independently 2,5-furandicarboxylic acid, terephthalic acid, or azelaic acid.

[0061] In certain examples, Ai and A2 may each be at least partially bio-based.

[0062] In certain examples, Gi may be ethylene glycol, trimethylene glycol, 1,4-butanediol, 1,4-cyclohexanedimethanol (“CHDM”), or 2,5-bis(hydroxylmethyl)furan.

[0063] In certain examples, Gi may be at least partially bio-based.

[0064] In certain examples, the resin may include from about 1 weight % to about 70 weight % of the polyethylene glycol oligomer.

[0065] In certain examples, the resin may include not more than about 60 weight % of the polyethylene glycol oligomer.

[0066] In certain examples, the resin may include from about 10 weight % to about 50 weight % of the polyethylene glycol oligomer.

[0067] In certain examples, the resin may include from about 30 weight % to about 99 weight % of the copolyester blocks combined.

[0068] In certain examples, the resin may include at least 5% bio-based components.

[0069] In certain examples, (G1A1) and (G1A2) may be substantially randomly distributed in the copolyester ether resin.

[0070] In certain examples, the polyethylene glycol oligomer may be segregated as a separate block.

[0071] In certain examples, (G1A1) and (G1A2) substantially encapsulate the polyethylene glycol oligomer.

[0072] In certain examples, the resin may have an intrinsic viscosity of at least about 0.5 dL/g. [0073] In certain examples, the resin may have an intrinsic viscosity of from about 0.6 dL/g to about 0.7 dL/g.

[0074] In certain examples, the resin may have an intrinsic viscosity of at least about 0.80 dL/g. [0075] In certain examples, the resin may have an intrinsic viscosity of from about 1.20 dL/g to about 1.50 dL/g.

[0076] In certain examples, the polyethylene glycol oligomer may exhibit a crystalline phase transition upon cooling or a melting phase transition upon heating within the temperature range of from about -50°C to about 70°C. [0077] In certain examples, a method of producing the resin may include: esterifying an aromatic or aliphatic dicarboxylic acid and a glycol to form a polyester segment; prepolymerizing a C2 to C12 linear or cyclic aliphatic diol having a functionality of two to form a polyether segment; and polycondensing the polyester segment and the polyether segment to produce the resin.

[0078] In certain examples, a method of producing a fiber may including spinning the resin to produce the fiber.

[0079] In certain examples, the method may produce a carpet fiber, a staple fiber, an apparel fiber, or a specialty low denier industrial fiber.

[0080] In certain examples, the fiber may range from 1 to 60 denier per filament (“dpf ’).

[0081] In certain examples, a method of producing a film may include extruding or coextruding the resin.

[0082] In certain examples, the method may include orienting or stretching the film.

[0083] In certain examples, the orienting or stretching may include tentering, machine direction orientation (“MDO”), double bubble, trapped bubble, or any combination thereof.

[0084] In yet another example, a bicomponent fiber may include a core including a polyethylene glycol (“PEG”) oligomer of a molecular weight of at least 500 g/mol; and a sheath outer layer including a thermoplastic, the sheath outer layer encapsulating the core.

[0085] In certain examples, the PEG oligomer may have a molecular weight of from about 600 g/mol to about 1000 g/mol.

[0086] In certain examples, the fiber may exhibit an enthalpy change of about 140 J/g PEG oligomer at a temperature of from about 20°C to about 30°C.

[0087] In certain examples, the PEG oligomer may have a molecular weight of from about 5500 g/mol to about 6500 g/mol.

[0088] In certain examples, the fiber may exhibit an enthalpy change of about 175 J/g PEG oligomer at a temperature of from about 35°C to about 45°C.

[0089] In certain examples, the thermoplastic may include a polyester, a nylon, a polyurethane, a polycarbonate, a polyolefin, a polyamide, or any combination thereof.

[0090] In certain examples, the PEG oligomer may include an antioxidant.

[0091] In certain examples, the fiber may include from about 25 weight percent to about 75 weight percent of the sheath outer layer relative to 100 weight percent of the bicomponent fiber. [0092] In certain examples, the fiber may include from about 25 weight percent to about 75 weight percent of the PEG core relative to 100 weight percent of the bicomponent fiber. [0093] In certain examples, the fiber may be staple cut fibers or continuous filament.

[0094] In certain examples, a garment may include the fiber.

[0095] In certain examples, the garment may include fabric that is nonwoven, woven, or knitted fiber.

[0096] In certain examples, a method of producing the fiber may include coextruding a thermoplastic and the PEG oligomer to provide the bicomponent fiber.

EXAMPLES

[0097] The present disclosure may be better understood in connection with the following Examples. In addition, the non-limiting examples are an illustration. The person skilled in the art will appreciate that it may be necessary to vary the procedures for any given example of the present disclosure, for example, vary the order or steps and/or the chemical reagents used.

[0098] L_ Initial Preparation of Copolyester Ether Resins.

[0099] A. Synthetic Methods.

[0100] In an example, a copolyester segment is esterified and pre-polymerized separately from a polyether segment, and the two segments are combined in a polycondensation step to finish the copolyester ether resin. In certain examples, batch or continuous esterification or transesterification processes may be used for production prior to a polycondensation step. In certain examples, esterification conditions may include a duration of from about 2 hours to about 6 hours, at a temperature of from about 180°C to about 240°C and a pressure of from about 0 to about 200 psig, depending upon the solubility of the dicarboxylic acids, the catalyst package, and the glycol excess amount. In certain examples, polycondensation conditions may include a duration of from about 2 hours to about 6 hours, at a temperature of from about 240°C to about 300°C (about 20°C to about 40°C above the melting point of the final polymer), and a vacuum below about 20 torr. In certain examples, glycol molar excess is in the range of about 1.01 to about 2.00.

[0101] In an example, a method of preparing a polyester ether resin may include an esterification reaction. Esterification may include:

Ai + 2Gi G1A1G1

A ₂ + 2Gi G1A2G1 wherein Ai and A2 are each independently aromatic or aliphatic dicarboxylic acids, and Gi is a glycol. Ai and A2 may each be the same or preferably different compounds. Ai and A2 may both be an aromatic dicarboxylic acid or an aliphatic dicarboxylic acid. Ai may be either an aromatic dicarboxylic acid or an aliphatic dicarboxylic acid and A2 may be the other of an aliphatic dicarboxylic acid or an aromatic dicarboxylic acid. Preferably, Ai and A2 are each different aromatic dicarboxylic acids. Ai may be at least partially bio-based. A2 may be at least partially bio-based. Preferably, Ai and A2 are each at least partially bio-based.

[0102] In an example, a method of preparing a polyester ether resin may include a polycondensation reaction. Polycondensation may include: n G1A1G1 + m G1A2G1 (GiAi)n(GiA ₂ )m + (n + m)Gi wherein n and m are numbers indicating a molar ratio of G1A1G1 to G1A2G1 used in the polycondensation reaction.

[0103] After several reactions, a copolyester ether resin of formula (GiAi) _x (PEG) _z (GiA2)y may be obtained, wherein x > n, y > m, and z > 1. The formula of the copolyester ether resin implies that (GiAi)x and (GiA2)y copolyester segments may be arranged as blocks within the copolyester ether resin on either side of a PEG block segment, thereby “encapsulating” a PEG “core” with copolyester segment “sheaths.” In certain examples, due to rapid ester interchange in the polycondensed melt, the (GiAi) _x and (GiAi)y copolyester segments may be substantially randomly distributed (for example, a random copolyester) but may stoichiometrically follow the x/y ratio in the amounts in which the copolyester segments are included in the copolyester ether resin. The PEG blocks identified stoichiometrically by the z subscript may be segregated as separate block segments in the interior of the copolyester ether resin, and may tend to insert and react as a distinct contiguous block, bound within the interior of the copolyester ether resin. [0104] The copolyester segments may encapsulate the PEG segment up to a composition of phase co-continuity, which may be typically in the polyester EG weight ratio of from 40:60 to 60:40 for a binary colyester ether resin. Depending upon the size, loading, and coalescence of the PEG segment, melting and crystallization phase change may be muted.

[0105] One solution to suppression of melting and crystallization phase change may be to encapsulate a PEG core within a thermoplastic resin sheath, the sheath serving as an outer protective layer.

[0106] In an example, a polymerization recipe for a copolyester ether resin produced in a 100- Ibm reactor is provided below in Table 1.

TABLE 1

[0107] For a copolyester ether resin, the rate of polycondensation may be affected by surface area renewal mass transfer. In certain examples, batch reactors may accomplish surface area renewal by impeller action. In other examples, continuous polycondensation reactors may utilize a rotating axis-symmetric assembly of baffled plates mounted on a rotor shaft to generate surface within a horizontal pressure (vacuum) vessel. In still other examples, falling strand of high specific surface may provide a high rate of mass transfer. In still other examples, polycondensation methods may incorporation a combination of two or more techniques. Methods and systems described herein may use all or some of the polycondensation methods to accomplish polycondensation and the finishing reaction of the copolyester ether resin.

[0108] In certain examples, melt-state polymerization may yield a precursor resin intrinsic viscosity of at least about 0.40 dL/g. The resin may be crystallized to reduce or prevent sticking in the solid-state polymerization (“SSP”) reactor. The crystallization conditions may be dependent upon copolyester ether segmental compositions and the respective lengths of the copolyester and polyether segments. SSP may be utilized to lift the resin intrinsic viscosity to about 0.64 dL/g for textile and/or apparel fiber applications, or as high as 0.9 to 1.0 dL/g for higher tenacity fibers and films. Depending upon the monomers of the copolyester ether resin, SSP conditions may fall within the ranges of a duration of about 6 to about 36 hours, at a temperature of about 180°C to about 240°C (for example, about 20 - 40°C below the peak melting temperature of the polymer), and less than about 20 torr.

[0109] In certain examples, the methods provided herein produce a copolyester ether resin in which a polyalkylene glycol segment is covalently bound within the chain, and due to the molecular size of the segment, the segment may phase segregate within the copolyester segment matrix. The copolyester segment may make up the major phase fraction of the copolyester ether resin, and the polyalkylene glycol ether segment may make up the minor phase fraction of the copolyester ether resin.

[0110] In certain examples, the methods provided herein covalently bond a bio-based poly ether glycol segment into the copolyester chain. Because the polyether glycol segment may be integrally bound within the copolyester chain, the phase change material, upon melting, may remain within the chain. In certain examples, the methods provided herein minimize or avoid having a phase change material simply compounded into a fiber, which thereby minimizes or avoids separation and migration to the surface of the fiber. In other examples, the methods provided herein may strengthen a fiber, because the PEG domain may be bound within the polymer chain and may minimize or avoid the role of the PEG domain as a stress concentrator. [OHl] In certain examples, the polyethylene glycol segment may be formed from polycondensation of a glycol.

[0112] B. Polymer Properties.

[0113] In certain examples, the segmented block copolyester ether resin may include a copolyester block segment and a polyethylene glycol block segment, and each block may be capable of independent crystallization if the crystallizable sequences in each block is long enough to fold and energetically stabilize into a crystalline lattice. In certain examples, the polyethylene glycol block segment may have an ability to reversibly crystallize and melt within a narrow temperature range specific to a particular phase change application. For example, in an example of a homopolyester, a crystalline melting temperature may be inversely proportional to the crystal lamella thickness. In another example, for the PEG block segment, a crystal thickness may be determined by the molecular weight of the linear PEG segment. By altering the length or molecular weight of the PEG segment, the melting temperature and enthalpy of the PEG phase change may be manipulated for a particular application. Table 2 summarizes the relationship between the PEG segment molecular weight and the PEG segment melting temperature.

TABLE 2

PEG melting temperature as a function of molecular weight

[0114] As illustrated by Table 2, linear combinations of PEG blocks may be formulated to yield a broad range endotherm and exotherm response for a given application, such as for engineering winter and summer clothing for enhanced comfort.

[0115] Additional literature data for PEG oligomers of various nominal molecular weights is provided below in Table 3. The data is available in R. Paberit, et al., Cycling Stability of Poly (ethylene glycol) of Six Molecular Weights: Influence of Thermal Conditions for Energy Applications, 3 ACS APPL. ENERGY MATER. 10578 (2020), the entirety of which is incorporated herein by reference. FIG. 10 depicts a plot of crystallization or melting enthalpy as a function of crystallization or melting temperatures for the various PEG oligomers in Table 3 below.

TABLE 3

Heating/cooling rates are ±5°C/min.

[0116] Table 4 below provides calculation of the expected heat exchange from a 50 weight % sheath and 50 weight % core bicomponent fiber relative to three nonwoven fabric insulation areal weights. To demonstrate the heating and cooling effect, the areal heat exchange was evaluated relative to the temperature increase or decrease in 1 kilogram of water spread over one square meter. FIG. 11 depicts a plot illustrating PEG melting enthalpies and crystallization enthalpies of PEG oligomers of various molecular weights from 400 to 6000 g/mol. FIG. 12 depicts a plot illustrating PEG peak melting temperatures and peak crystallization temperatures of PEG oligomers of various molecular weights from 400 to 6000 g/mol.

TABLE 4 weight % thermoplastic sheath and 50 weight % PEG core. Ambient - civilian apparel. Desert - military apparel.

[0117] C. Fiber Spinning.

[0118] In certain examples of the polyester ether resin, standard spinning conditions may be specified based on maintaining a spinning temperature that may be 20°C to 30°C higher than the peak melting temperature of the copolyester segment. In certain examples, for adequate spinnability for continuous fiber spinning, the intrinsic viscosity of the copolyester ester resin may be above about 0.5 dL/g, or above about 0.6 dL/g, or from about 0.6 to about 0.7 dL/g. Low (for example, less than 1000 m/min), medium (for example, from 1000 m/min to 3000 m/min), and high (for example, greater than 3000 m/min) spinning speeds may be attainable if the intrinsic viscosity and spinning temperature are within the acceptable ranges as provided herein. The spinning speed ranges provided herein may enable successful production of carpet, staple, apparel, and specialty low denier industrial fibers. In certain examples, fibers ranging from 1 to 60 dpf (denier per filament) may be attainable by the copolyester ether resins described herein. Uniaxial extension of a PEG block may increase phase surface area within the copolyester phase, enhancing heat transfer and phase change rate.

[0119] As used herein, the term “denier” may refer to the mass linear density of a fiber or fiber bundle in grams of fiber per 9000 m of fiber.

[0120] D. Film Extrusion.

[0121] In certain examples, the copolyester ether resin provided herein may be extruded or coextruded into cast articles, blown articles, and laminated films, and subsequently oriented or stretched by methods including tentering, machine direction orientation (“MDO”), double bubble, trapped bubble, or any combination thereof. Depending upon the compositions of the polyethylene glycol segments, the glass transition temperature (T _g ) of the copolyester segment may enable satisfactory solid-state orientation of a film within a temperature range of -5°C to 15°C bracketing the copolyester segment T _g . In certain examples, formulation of a copolyester segment of a polymer leads to solid-state orientation out of a wide range of heating media including hot water baths, infrared ovens, and hot air ovens.

[0122] II, Preparation of Copolyester Ether (“COPE”) Resins. [0123] Block COPE resins formed with PEG were prepared and characterized via differential scanning calorimetry. A block copolyester including a 10 mol % poly(ethylene terephthalate- co-ethylene 2,5-furandicarboxylate) copolyester and two separate PEG block segments — a first PEG block segment of 2000 g/mol and a second PEG block segment of 4000 g/mol — were produced at PolyTech Resources LLC (“PTR”) in Darlington, SC. The COPE resins were melted and spun into fibers for testing and evaluation at Gaston College in Belmont, NC.

[0124] The structural formula of poly(ethylene terephthalate-co-ethylene 2,5- furandicarboxylate) is as follows: poly(ethylene terephthalate-co-ethylene 2,5-furandicarboxylate).

Polyethylene terephthalate-co-ethylene 2,5-furandicarboxylate) may be abbreviated as “PETF” when p > q, and as PEFT when q > p.

[0125] PETF -PEG copolyester ether (COPE) resins may be produced by copolymerizing a 10 mol % PETF copolyester with poly(ethylene glycol) (PEG) resins with nominal molecular weights of 2000 and 4000 g/mol, yielding block copolymers. PEG modification produces COPE resins with surprisingly excellent spinnability, elongation, and elasticity, contrary to results reported in the literature for analogous COPE resins copolymerized with polyethylene 2,5-furandicarboxylate (“PEF”). The findings suggest that an effective means of producing a phase change fiber is by encapsulating a high molecular weight PEG resin core (>4000 g/mol) within a 2,5-furandicarboxylate polyester (for example, PEF) or copolyester (PETF or PEFT) to yield a phase change fiber with desirable spinning/drawing performance, resistance to aqueous dissolution during laundering, and adequate resistance to oxidation.

[0126] PEG modification increased PETF peak melting temperatures as the length of the PEG block increased from 0 to 4000 g/mol, indicating that flexible block copolymers such as PEG may be used to increase the mobility of the copolyester segment of the chain, resulting in faster nucleation and crystallization rates, while limiting lamellar thickness to control melt temperature.

[0127] A. COPE Formulation and Synthesis. [0128] Table 5 lists the reagents, catalysts, and additives used to formulate the COPE resins described herein.

TABLE 5

Reagents, catalysts, and additives used in this study to prepare COPE resins.

[0129] Table 6 lists the individual synthesis recipes for the formations of the PETF10- PEG2000 and PETF10-PEG4000 COPE resins. Tetramethylammonium hydroxide (TMAH) was added for di ethylene glycol formation suppression, and BASF Irganox® 1010 was incorporated as an antioxidant/thermal stabilizer to protect the PEG statement at the polycondensation segment. BASF Irganox® 1010 has the following structural formula:

pentaerythritol tatrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl) (BASF Irganox(R) 1010).

TABLE 6

Direct esterification/polycondensation batch recipes used to produce the COPE resins

[0130] Direct esterification proceeded with 20% glycol excess for both COPE resins, and the polycondensation time under vacuum was held at a constant 89 minutes at 280°C for both COPE resins. PEG was added at the end of the direct esterification reaction and before the vacuum stage was initiated for the polycondensation step.

[0131] B. Melt Spinning and Filament Production.

[0132] Monofilaments were melt spun at Gaston College on a single position piston-driven spin line. The melt volumetric output rate for the monofilament was constant at 1.40 cm ³ /min with a take-up speed of 310 m/min, which was also held constant. Spinning conditions are summarized in Table 7. Both COPE resins exhibited excellent spinnability on the monofilament line at the imposed spinning conditions. Filaments were wound onto paper cores for subsequent analytical characterization.

TABLE 7

Monofilament spinning conditions employed for the PETF COPE and PETF control resins.

[0133] C. Analytical Characterization of COPE Pellets and Filaments.

[0134] Both COPE resins were characterized according to their appearances and CIE L*a*b* colors. As understood, the CIE L*a*b* color space is a color scale for determining a color. The three coordinates (or dimensions/components) of CIE L*a*b* represent the lightness of the color (L*=0 indicates black and L*=100 indicates white), the position between red (sometimes referenced as magenta) and green (negative a* values indicate green while positive a* values indicate red), and the position between yellow and blue (negative b* values indicate blue and positive b* values indicate yellow). The L* component closely matches human perception of lightness.

[0135] COPE spun filaments were analyzed using differential scanning calorimetry (“DSC”). Measured resin and filament properties are reviewed in Table 8. The DSC scans for PETF10- PEG2000, PETF10-PEG4000, and PETF10 control resin pellets, and filaments prepared therefrom, are illustrated in FIGs. 1 to 8.

TABLE 8

Specified, measured, and calculated PETF-PEG COPE resin properties. molecular weight. (2) The characteristic ratio of PEG was taken from Jozef Bicerano, Prediction of Polymer Properties, Second Edition, Marcel Dekker, Inc., 1996, the entirety of which is incorporated by reference herein. (3) The radius of gyration was computed using the relationship <Rg> = where the bond lengths h were taken as the standard bond lengths for C-C (1.54A) and C-0 (1.43 A). (4) The weight-average molecular weight of the chain M-w was calculated using the Mark-Houwink equation: IV (dg/L) = KMw ^a , where the values for Mark-Houwink coefficient K and exponent a were assumed to be the same as for PET, where K = 4.80- 10' ⁴ (dL mole ^a /g ^a+1 ) and a = 0.68. Additionally, in the absence of other supporting data, it was assumed that the COPE resin retains its most probable molecular weight distribution with a poly dispersity of 2, or in other words, = 2 M _a .

[0136] D Discussion.

[0137] 1. PETF-PEG COPE Resin.

[0138] The measured final intrinsic viscosities for the COPE resins after SSP were 0.85 dL/g for PETF10-PEG2000 and 0.79 dL/g for PETF10-PEG4000. The intrinsic viscosity of the PETF10 control resin was 0.64 dL/g. It was observed that for the same polycondensation time, the PETF-PEG COPE resins reached higher intrinsic viscosities at the end of polymerization compared to the 10 mol % PETF copolyester control.

[0139] The crystallized COPE resins exhibited more yellow color than the PETF 10 control resin. While the PETF10-PEG2000 resin was slightly more yellow than the PETF control, the PETF10-PEG4000 resin included a varied mixture of resin pellets ranging from dark brown to light tan. The increased color of PETF10-PEG4000 resin may be due to trace metal contamination of the FDCA in one or more of the containers sent to PTR, PEG thermal degradation, and/or FDCA contamination. PETF-PEG batches incorporated 500 ppm of BASF Irganox® 1010 antioxidant.

[0140] Extruded PETF-PEG COPE batch strands were cooled in an ice bath quench trough. By maintaining PEG addition to COPE resins to 15 weight % or less, the quench bath may cool the extruded strand to a low enough temperature to enable the strand cutter to produce clean- cut pellets without stringing.

[0141] 2. COPE Filaments.

[0142] Table 9 below provides a summary of DSC first scan data and intrinsic viscosity results for the PETF-PEG COPE resin pellets and filaments as well as the PETF control resin pellets and filaments.

TABLE 9

Tg denotes the glass transition temperature, T _cc denotes the peak temperature of the cole crystallization exotherm, T _m ,i denotes the first melting peak temperature, and T _m ,2 denotes the second melting peak temperature observed in the DSC scan.

[0143] Using data in Table 10 below, and data reported in Maria Konstantopolou, Poly(ethylene furanoate-co-ethylene terephthalate) biobased copolymers: Synthesis, thermal properties and cocrystallization behavior, 89 EUR. POLYM. J. 349 (2017), the entirety of which is incorporated by reference herein, the glass transition temperature was predicted for PETF- PEG COPE resins according to the Fox Equation. The Fox Equation is an additivity rule that has been used successfully to model the glass transition behavior of random copolymers and fully miscible polymer blends, and is provided below in formula (I): where w, are the relative weight percents of the various component block polymers in a combined copolymer, and T _g , _; are the respective glass transition temperatures, in K, of the component block polymers. T _g of PETF is observed to be 85.5°C.

TABLE 10

Taken from sigmaaldrich.com.

[0144] The Fox Equation in formula (I) predicted a glass transition temperature that was approximately 10°C higher than observed experimentally in Table 9, indicating that distinct phase morphologies for the PETF-PEG COPE resins existed in the pellet and are differentiated from those of the filament. The glass transition temperatures for the pellets are observed to be closer to the glass transition of the PETF10 control, whereas the glass transition temperature of the filament is shifted about 42 - 45°C lower. For the pellets, the glass transition of the PEG phase is not observed due to its occurrence at -60°C, as noted in Table 10, and which is well below the temperature range of the DSC thermal scan start (20°C). The drawdown ratio for the spun filament was 44.9, suggesting that PETF-PEG COPE morphology was modified by filament stretching to enable the PEG segment to engage and enhance greater cooperativity between the PETF and PEG segments, leading to greater mobility of the PETF block.

[0145] Improvement in PETF block mobility was further confirmed by the exhibition of a cold crystallization exotherm (at peak temperature T _cc ) in the filament PETF-PEG COPE DSC scans. The cold crystallization exotherm for the control PETF 10 copolyester was not observed, indicating that the mobility of the PETF copolyester was insufficient to permit crystalline nucleation during the filament sample heating scan rate of 10°C/min. Neither pellets nor filaments exhibited a phase change consistent with the peak melting temperature of PEG (57.5°C) in the molecular weight range in Table 10.

[0146] FIG. 9 illustrates how the size of the PEG segment affects the glass transition (T _g ) and melting transitions (T _m ,2) of the PETF-PEG COPE resins. For the two PEG segments evaluated, T _m ,2 linearly increases with the size of the PEG block from 0 to 4000 g/mol. Glass transition temperatures decrease gradually for the pellet, but abruptly by 42 - 45°C as PEG is incorporated into the copolyester.

[0147] Consistent with the resin pellets, produced filaments possessed a creamy, off-white color for the PETF10-PEG2000 resin, and a light golden-brown color for the PETF 10- PEG4000 resin. Spinnability was excellent at the spinning speed at 310 m/min with no slubs, drips, or breaks evident during the spinning trials. Previous trials performed across PEGs with broader molecular weight ranges of 400 to 10000 demonstrated poor spinnability at 20 m/min, which was substantially lower than the spinning speed demonstrated herein, and possessed unreacted PEG domains dispersed within the copolyester due to incomplete reactions during polymerization for PEG chains of 6000 g/mol molecular weights and higher.

[0148] Because the PETF and PEG segments constitute separate blocks in the COPE copolyester ether resins, some average characteristics of the chain may be estimated by simple calculations based on the foregoing data. Table 11 summaries the results of the calculations and reveals how the PETF block length changes with PEG molecular weight for a 15 weight percent addition of PEG. For PETF10-PEG2000, the PETF block length is 13,333 g/mol, or 45 average repeat units based upon the average repeat unit molecular weight of a PETF 10 copolyester (191.17 g/mol). Assuming the cooling characteristics of the PET and PEG chains in solution are similar (C«>,PEG = 4.06 and C«>,PET = 3.54), the average number of PEG blocks per number-average PETF 10-PEG2000 chain is 1.26. For the PETF 10-PEG4000 COPE resin, the average PETF block length is 26,667 g/mol and the number of PEG blocks per numberaverage PETF10-PEG4000 chain is 1.26, values which are consistent with the higher T _m ,2 melting temperatures listed in Table 9 and plotted in FIG. 9. Longer average PETF crystallizable sequence lengths will facilitate the formation of thicker crystalline lamellae. The increased chain mobility afforded by the incorporated PEG block segment enables higher nucleation and crystallization growth rates favoring thicker crystalline lamellae and higher melting temperatures, whereas for polyethylene 2,5-furandicarboxylate (“PEF”), a rise in peak melting temperature up to PEG2000 and a leveling of peak melting temperature for longer PEG blocks has been observed.

TABLE 11

Calculated PETF-PEG COPE Average Molecular Characteristics Based on Data in Table 8

[0149] The foregoing PETF polymerization and extrusion experimental data indicate that a PETF copolyester bicomponent fiber encapsulating a PEG core will surprisingly and advantageously provide a desirable phase change fiber. The coextrusion encapsulation of the PEG within a 2,5-furandicarboxylate polyester or copolyester sheath would allow for a continuous PEG phase extent enabling faster crystallization and the formation of thicker crystalline lamellae for better phase change properties. By encapsulating a relatively high molecular weight (>4000 g/mol) PEG core layer (center block segment) sheathed in a PETF copolyester outer layer (outer block segments), the PEG core may be effectively protected against aqueous dissolution and oxidation, and PETF reactivity may be rendered moot except for sheath-core interlayer adhesion.

[0150] PEGs may be susceptible to thermal oxidative damage due to chain scission. The encapsulation of PEG block segments within PETF copolyester sheaths of bicomponent fibers may provide protection against oxidation. Because PEGs are generally hygroscopic and water- soluble, encapsulation within PETF copolyesters in small-diameter fibers or filaments may impede moisture attack and dissolution of the PEG and may avoid leaching of the PEG from the filament when immersed in an aqueous environment, such as during laundering of a garment. A bicomponent sheath-core fiber may be spun and drawn similarly to a homogeneous fiber, because the sheath bears most of the stress caused by spinning and drawing processes.

[0151] As used herein, the term “tentering” refers to a process of stretching and setting a woven fabric to final dimensions of the fabric by the use of a tenter frame, which includes chains fitted with pins or clips to hold the selvedges of the fabric, and traveling on tracks.

[0152] As used herein, the term “machine direction orientation (MDO)” refers to a process of drawing a film or sheet between rolls rotating at different speeds, a second set of rolls running faster than a first set. The first set of rolls stabilizes the sheet surface temperature and allows time for inner sheet temperature balance. A nip controls simultaneous rolling and stretching at optimum orientation temperature. The second set of rolls are used for heat setting and/or cooling the uniaxially stretched polymeric sheet. The stretching is typically 3 to 16 times the size of the original film or sheet. Often, MDO is the first step of biaxial orientation and may be followed by transverse direction orientation.

[0153] As used herein, the term “double bubble” refers to a process used to produce biaxially orientated film, the process characterized by simultaneous stretching in the machine and transverse directions, resulting in orientation similar to the conventional tenter process.

[0154] As used herein, the term “trapped bubble” refers to a process of inflating an extruded tube such that the gas used for inflation is “trapped” between the extrusion die and a pair of pinch rolls, the pinch rolls stretching the extruded tube in the longitudinal direction.

[0155] The uses of the terms “a” and “an” and “the” and similar referents in the context of describing the present disclosure (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The use of the term “plurality of’ is defined by the Applicant in the broadest sense, superseding any other implied definitions or limitations hereinbefore or hereinafter unless expressly asserted by Applicant to the contrary, to mean a quantity of more than one. All methods described herein may be performed in any suitable order unless otherwise indicated herein by context.

[0156] As will be understood by one skilled in the art, for any and all purposes, all ranges recited herein also encompass any and all possible sub-ranges and combinations of sub-ranges thereof, as well as the individual values making up the range, particularly integer values. It is therefore understood that each unit between two particular units is also disclosed. For example, if “10 to 15” is disclosed, then 11, 12, 13, and 14 are also disclosed, individually, and as part of a range. A recited range (for example, weight percentages or carbon groups) includes each specific value, integer, decimal, or identity within the range. Any listed range may be easily recognized as sufficiently describing and enabling the same range being broken down into at least equal halves, thirds, quarters, fifths, or tenths. As will also be understood by one skilled in the art, all language such as “up to,” “at least,” “greater than,” “less than,” “more than,” “or more,” and the like, include the number recited and such terms refer to ranges that can be subsequently broken down into sub-ranges. In the same manner, all ratios recited herein also include all sub-ratios falling within the broader ratio. Accordingly, specific values recited for radicals, substituents, and ranges are for illustration only; they do not exclude other defined values or other values within defined ranges for radicals and substituents. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint.

[0157] One skilled in the art will also readily recognize that where members are grouped together in a common manner, such as in a Markush group, the invention encompasses not only the entire group listed as a whole, but each member of the group individually and all possible subgroups of the main group. Additionally, for all purposes, the invention encompasses not only the main group, but also the main group absent one or more of the group members. The invention therefore envisages the explicit exclusion of any one or more of members of a recited group. Accordingly, provisos may apply to any of the disclosed categories or examples whereby any one or more of the recited elements, species, or examples may be excluded from such categories or examples, for example, for use in an explicit negative limitation.

[0158] As used herein, the terms “comprise(s),” “include(s),” “having,” “has,” “can,” “contain(s),” and variants thereof, are intended to be open-ended transitional phrases, terms, or words that do not preclude the possibility of additional acts or structures. The present description also contemplates other examples “comprising,” “consisting of,” and “consisting essentially of,” the examples or elements presented herein, whether explicitly set forth or not. [0159] Unless otherwise defined, all terms used herein, including technical or scientific terms, having the same meanings as those generally understood by those skilled in the art to which the present disclosure pertains. Such terms as those defined in a generally used dictionary are to be interpreted as having meanings equal to the contextual meanings in the relevant field of art.

[0160] As used herein, the term “about,” when used in the context of a numerical value or range set forth means a variation of ±15%, ±14%, ±10%, or ±5%, among others, would satisfy the definition of “about,” unless more narrowly defined in particular instances.

[0161] Although the present disclosure has been described with reference to examples and the accompanying drawings, the present disclosure is not limited thereto, but may be variously modified and altered by those skilled in the art to which the present disclosure pertains without departing from the spirit and scope of the present disclosure.

[0162] The subject-matter of the disclosure may also relate, among others, to the following aspects:

[0163] A first aspect relates to a segmented copolyester ether resin, comprising: a polyester block covalently bonded to a polyether block; wherein the copolyester ether resin is formed by esterification and polycondensation reactions comprising an aromatic or aliphatic dicarboxylic acid, a glycol, and a polyethylene glycol (“PEG”) oligomer; and wherein the PEG oligomer has a molecular weight of at least 500 g/mol.

[0164] A second aspect relates to the resin of aspect 1, wherein the PEG oligomer has a molecular weight of at least 2000 g/mol.

[0165] A third aspect relates to the resin of any preceding aspect, wherein the PEG oligomer has a molecular weight of at least 4000 g/mol.

[0166] A fourth aspect relates to the resin of any preceding aspect, wherein the aromatic or aliphatic dicarboxylic acid comprises 2,5-furandicarboxylic acid, terephthalic acid, and/or azelaic acid.

[0167] A fifth aspect relates to the resin of any preceding aspect, wherein the aromatic or aliphatic dicarboxylic acid is at least partially bio-based.

[0168] A sixth aspect relates to the resin of any preceding aspect, wherein the glycol is a C2 or C12 linear cyclic aliphatic diol having a functionality of two.

[0169] A seventh aspect relates to the resin of any preceding aspect, wherein the glycol comprises ethylene glycol, trimethylene glycol, 1,4-butanediol, 1,4-cyclohexanedimethanol (“CHDM”), and/or 2,5-bis(hydroxylmethyl)furan.

[0170] An eighth aspect relates to the resin of any preceding aspect, wherein the glycol is at least partially bio-based.

[0171] A ninth aspect relates to the resin of any preceding aspect, comprising from about 1 weight % to about 70 weight % of the PEG oligomer.

[0172] A tenth aspect relates to the resin of any preceding aspect, comprising not more than about 60 weight % of the PEG oligomer.

[0173] An eleventh aspect relates to the resin of any preceding aspect, comprising from about 10 weight % to about 50 weight % of the PEG oligomer.

[0174] A twelfth aspect relates to the resin of any preceding aspect, comprising from about 30 weight % to about 99 weight % of the polyester block.

[0175] A thirteenth aspect relates to the resin of any preceding aspect, comprising at least 5% bio-based components.

[0176] A fourteenth aspect relates to a segmented copolyester ether resin of formula (II): (GiAi)x(PEG)z(GiA ₂ ) _y (II), wherein: Ai is an aromatic or aliphatic dicarboxylic acid; A2 is an aromatic or aliphatic dicarboxylic acid; Gi is a glycol; (G1A1) and (G1A2) are each polyester blocks; PEG is a polyethylene glycol oligomer comprising a terminal group capable of covalently bonding to hydroxyl groups and/or a terminal group capable of covalently bonding to terminal carboxylic acid groups, the polyethylene glycol oligomer having a molecular weight of at least 500 g/mol; x > 1 ; y > 1 ; and z > 1.

[0177] A fifteenth aspect relates to the resin of aspect 14, wherein the polyethylene glycol oligomer has a molecular weight of at least 2000 g/mol.

[0178] A sixteenth aspect relates to the resin of aspects 14 or 15, wherein the polyethylene glycol oligomer has a molecular weight of at least 4000 g/mol.

[0179] A seventeenth aspect relates to the resin of aspects 14 to 16, wherein Ai and A2 are each independently 2,5-furandicarboxylic acid, terephthalic acid, or azelaic acid.

[0180] An eighteenth aspect relates to the resin of aspects 14 to 17, wherein Ai and A2 are each at least partially bio-based.

[0181] A nineteenth aspect relates to the resin of aspects 14 to 18, wherein Gi is ethylene glycol, trimethylene glycol, 1,4-butanediol, 1,4-cyclohexanedimethanol (“CHDM”), or 2,5- bis(hydroxylmethyl)furan.

[0182] A twentieth aspect relates to the resin of aspects 14 to 19, wherein Gi is at least partially bio-based.

[0183] A twenty-first aspect relates to the resin of aspects 14 to 20, comprising from about 1 weight % to about 70 weight % of the polyethylene glycol oligomer.

[0184] A twenty-second aspect relates to the resin of aspects 14 to 21, comprising not more than about 60 weight % of the polyethylene glycol oligomer.

[0185] A twenty -third aspect relates to the resin of aspects 14 to 22, comprising from about 10 weight % to about 50 weight % of the polyethylene glycol oligomer.

[0186] A twenty-fourth aspect relates to the resin of aspects 14 to 23, comprising from about 30 weight % to about 99 weight % of the copolyester blocks combined.

[0187] A twenty-fifth aspect relates to the resin of aspects 14 to 24, comprising at least 5% bio-based components.

[0188] A twenty-sixth aspect relates to the resin of aspects 14 to 25, wherein (G1A1) and (G1A2) are substantially randomly distributed in the copolyester ether resin.

[0189] A twenty-seventh aspect relates to the resin of aspects 14 to 26, wherein the polyethylene glycol oligomer is segregated as a separate block.

[0190] A twenty-eighth aspect relates to the resin of aspects 14 to 27, wherein (G1A1) and (G1A2) substantially encapsulate the polyethylene glycol oligomer. [0191] A twenty-ninth aspect relates to the resin of any preceding aspect, having an intrinsic viscosity of at least about 0.5 dL/g.

[0192] A thirtieth aspect relates to the resin of any preceding aspect, having an intrinsic viscosity of from about 0.6 dL/g to about 0.7 dL/g.

[0193] A thirty-first aspect relates to the resin of aspects 1 to 28, having an intrinsic viscosity of at least about 0.80 dL/g.

[0194] A thirty-second aspect relates to the resin of aspects 1 to 29 and 31, having an intrinsic viscosity of from about 1.20 to about 1.50 dL/g.

[0195] A thirty-third aspect relates to the resin of any preceding aspect, wherein the polyethylene glycol oligomer exhibits a crystalline phase transition upon cooling or a melting phase transition upon heating within the temperature range of from about -50°C to about 70°C. [0196] A thirty-fourth aspect relates to a method of producing the resin of any preceding aspect, comprising: esterifying an aromatic or aliphatic dicarboxylic acid and a glycol to form a polyester segment; pre-polymerizing a C2 to C12 linear or cyclic aliphatic diol having a functionality of two to form a polyether segment; and polycondensing the polyester segment and the polyether segment to produce the resin.

[0197] A thirty-fifth aspect relates to a method of producing a fiber, comprising spinning the resin of aspects 1 to 33 to produce the fiber.

[0198] A thirty-sixth aspect relates to the method of aspect 35, wherein the method produces a carpet fiber, a staple fiber, an apparel fiber, or a specialty low denier industrial fiber.

[0199] A thirty-seventh aspect relates to the method of aspect 35 or 36, wherein the fiber ranges from 1 to 60 denier per filament (“dp ’).

[0200] A thirty-eighth aspect relates to a fiber produced by the method of aspects 35 to 37.

[0201] A thirty-ninth aspect relates to a method of producing a film, comprising extruding or coextruding the resin of aspects 1 to 33.

[0202] A fortieth aspect relates to the method of aspect 39, further comprising orienting or stretching the film.

[0203] A forty-first aspect relates to the method of aspect 40, wherein the orienting or stretching comprises tentering, machine direction orientation (“MDO”), double bubble, trapped bubble, or any combination thereof.

[0204] A forty-second aspect relates to a film produced by the method of aspects 39 to 41. [0205] A forty-third aspect relates to a bicomponent fiber, comprising: a core comprising a polyethylene glycol (“PEG”) oligomer of a molecular weight of at least 500 g/mol; and a sheath outer layer comprising a thermoplastic, the sheath outer layer encapsulating the core.

[0206] A forty-fourth aspect relates to the fiber of aspect 43, wherein the polyethylene glycol (PEG) oligomer has a molecular weight of from about 600 g/mol to about 1000 g/mol.

[0207] A forty-fifth aspect relates to the fiber of aspect 44, wherein the fiber exhibits an enthalpy change of about 140 J/g PEG oligomer at a temperature of from about 20°C to about 30°C.

[0208] A forty-sixth aspect relates to the fiber of aspect 43, wherein the polyethylene glycol oligomer has a molecular weight of from about 5500 g/mol to about 6500 g/mol.

[0209] A forty-seventh aspect relates to the fiber of aspect 46, wherein the fiber exhibits an enthalpy change of about 175 J/g PEG oligomer at a temperature of from about 35°C to about 45°C.

[0210] A forty-eighth aspect relates to the fiber of aspects 43 to 47, wherein the thermoplastic comprises a polyester, a nylon, a polyurethane, a polycarbonate, a polyolefin, a polyamide, or any combination thereof.

[0211] A forty-ninth aspect relates to the fiber of aspects 43 to 48, wherein the PEG oligomer comprises an antioxidant.

[0212] A fiftieth aspect relates to the fiber of aspects 43 to 49, comprising from about 25 weight percent to about 75 weight percent of the sheath outer layer relative to 100 weight percent of the fiber.

[0213] A fifty-first aspect relates to the fiber of aspects 43 to 50, comprising from about 25 weight percent to about 75 weight percent of the PEG oligomer relative to 100 weight percent of the fiber.

[0214] A fifty-second aspect relates to the fiber of aspects 43 to 51, which are staple cut fibers or continuous filament.

[0215] A fifty-third aspect relates to a garment comprising the fiber of aspects 43 to 52.

[0216] A fifty-fourth aspect relates to the garment of aspect 53, comprising fabric that is nonwoven, woven, or knitted fiber.

[0217] A fifty-fifth aspect relates to a method of producing the fiber of aspects 43 to 51, comprising extruding the thermoplastic and the PEG oligomer to provide the bicomponent fiber. [0218] In addition to the features mentioned in each of the independent aspects enumerated above, some examples may show, alone or in combination, the optional features mentioned in the dependent aspects and/or as disclosed in the description above and shown in the figures.