Patent Application
20240360598
Non-stretch yarns, such as polyesters, and nylons, are commonly used to make articles such as fabrics and home furnishings. The filaments utilized in making such yarns can be spun while minimizing filament breakage and corresponding breakage may also be minimized during fabric processing. Another class of materials, namely thermoplastic copolyester elastomers, have recently been used for various applications because of their ability to function as thermoplastics, in particular the ability to be reformed upon heating, while also exhibiting certain properties typical of elastomers. As a result, these materials may also be utilized as elastomeric stretch yarns for forming various articles. However, these yarns may have a higher than desired propensity to break during spinning and/or further processing. In addition, when utilizing multifilament yarns made from such thermoplastic copolyester elastomers, the individual filaments may separate from the yarn bundle during unwinding and/or further processing thereby compromising the integrity of the yarn and the resulting article.
Thus, there remains a need to overcome certain issues related to the use of thermoplastic copolyester elastomers in order to provide an improved thermoplastic copolyester elastomer filament as well as resulting yarns and articles.
In accordance with one embodiment of the present disclosure, a yarn is disclosed. The yarn comprises a filament that is formed from a thermoplastic copolyester elastomer composition comprising a thermoplastic copolyester elastomer containing hard segments and soft segments. The thermoplastic copolyester elastomer exhibits a flexural modulus of about 300 MPa or less as determined in accordance with ISO 178:2019 at a temperature of about 23° C. and a melting temperature of from about 100° C. to about 230° C. as determined in accordance with ISO 11357-3:2018. The yarn has a linear density of from about 1 to about 2000 denier per filament and exhibits an elongation at break of about 300% or more as determined in accordance with ASTM D2653-07(2018) at a temperature of about 23° C.
In accordance with another embodiment of the present disclosure, a method of making the aforementioned yarn is disclosed. The method comprises: extruding a melt comprising the thermoplastic copolyester elastomer composition comprising the thermoplastic copolyester elastomer through a spinneret; withdrawing a filament from the spinneret; and collecting the filament on a winding roller.
Other features and aspects of the present disclosure are set forth in greater detail below.
A full and enabling disclosure of the present disclosure is set forth more particularly in the remainder of the specification, including reference to the accompanying figures, in which:
Repeat use of reference characters in the present specification and drawings is intended to represent the same or analogous features or elements of the present invention.
It is to be understood by one of ordinary skill in the art that the present discussion is a description of exemplary embodiments only and is not intended as limiting the broader aspects of the present disclosure.
Generally speaking, the present disclosure is directed to a thermoplastic copolyester elastomer-based yarn. The present inventors have discovered that by utilizing a thermoplastic copolyester elastomer as disclosed herein, a filament and resulting yarn having the desired properties for various applications, in particular textile applications, can be obtained. In particular, by utilizing a thermoplastic copolyester elastomer-based yarn as disclosed herein, a resulting article may be lighter, may dry faster, and/or may be more breathable than other materials. In addition, because the thermoplastic copolyester elastomer can be reformed upon heating like thermoplastics, the yarns and resulting articles formed from the thermoplastic copolyester elastomer may contribute to an ecosystem of recyclability and circularity. For instance, these materials may be repurposed and reformed and thus may not necessarily need to be disposed unlike other types of materials typically utilized.
In addition, the properties of the thermoplastic copolyester elastomer and the resulting filaments and yarns allow for the use of these materials for overcoming certain prior issues. For instance, the yarn, having greater than 300% elongation, may be spun at relatively high speeds to form resulting articles while minimizing filament and yarn breakage. In addition, the yarn may also result in fewer faults (e.g., drop stitches, holes, bad selvages, broken filaments, yarn breaks, inconsistent yarn denier in fabric, etc.) during knitting applications.
In this regard, to obtain such beneficial properties, the thermoplastic copolyester elastomer utilized in making the filament and yarn may exhibit a certain mechanical strength. In particular, the thermoplastic copolyester elastomer may not be as likely to resist deformation in bending compared to other types of materials and as a result, the thermoplastic copolyester elastomer may exhibit a relatively low flexural modulus. For instance, the flexural modulus may be about 300 MPa or less, such as about 260 MPa or less, such as about 220 MPa or less, such as about 200 MPa or less, such as about 190 MPa or less, such as about 180 MPa or less, such as about 170 MPa or less, such as about 160 MPa or less, such as about 150 MPa or less, such as about 140 MPa or less, such as about 130 MPa or less, such as about 120 MPa or less, such as about 110 MPa or less, such as about 100 MPa or less, such as about 90 MPa or less, such as about 80 MPa or less, such as about 70 MPa or less, such as about 60 MPa or less, such as about 50 MPa or less, such as about 40 MPa or less, such as about 30 MPa or less, such as about 20 MPa or less. The flexural modulus may be about 10 MPa or more, such as about 15 MPa or more, such as about 20 MPa or more, such as about 25 MPa or more, such as about 30 MPa or more, such as about 35 MPa or more, such as about 40 MPa or more, such as about 45 MPa or more, such as about 50 MPa or more, such as about 60 MPa or more, such as about 70 MPa or more, such as about 80 MPa or more, such as about 90 MPa or more, such as about 100 MPa or more, such as about 110 MPa or more, such as about 120 MPa or more, such as about 130 MPa or more, such as about 140 MPa or more, such as about 150 MPa or more, such as about 180 MPa or more, such as about 200 MPa or more. The flexural modulus may be determined in accordance with ISO 178:2019 at a temperature of about 23° C.
Relatedly, the thermoplastic copolyester elastomer may have a particular Shore D hardness, which can provide an indication of the resistance to indentation of the thermoplastic copolyester elastomer. In this regard, the Shore D hardness may be about 15 or more, such as about 20 or more, such as about 25 or more, such as about 30 or more, such as about 35 or more, such as about 40 or more, such as about 45 or more, such as about 50 or more. The Shore D hardness may be about 60 or less, such as about 55 or less, such as about 50 or less, such as about 45 or less, such as about 40 or less, such as about 35 or less, such as about 30 or less. Such hardness may allow for the thermoplastic copolyester elastomer to provide the compliance necessary to effectively function for use in filaments/yarns and resulting articles. The Shore D hardness may be determined in accordance with ISO 868-2003 (15 seconds).
In addition, the thermoplastic copolyester elastomer may have other beneficial mechanical properties. For instance, the tensile stress at break may be about 45 MPa or less, such as about 40 MPa or less, such as about 35 MPa or less, such as about 30 MPa or less, such as about 30 MPa or less, such as about 25 MPa or less. The tensile stress at break may be about 5 MPa or more, such as about 10 MPa or more, such as about 15 MPa or more, such as about 20 MPa or more, such as about 25 MPa or more, such as about 30 MPa or more, such as about 35 MPa or more. The tensile stress at break may be determined in accordance with ISO 527-1/-2 (2012) at a temperature of about 23° C.
Also, the thermoplastic copolyester elastomer may have a relatively high nominal strain at break. For instance, the nominal strain at break may be about 200% or more, such as about 250% or more, such as about 300% or more, such as about 350% or more, such as about 400% or more, such as about 450% or more, such as about 500% or more, such as about 550% or more, such as about 600% or more, such as about 650% or more, such as about 700% or more, such as about 750% or more, such as about 800% or more, such as about 850% or more. The nominal strain at break may be about 2000% or less, such as about 1800% or less, such as about 1600% or less, such as about 1400% or less, such as about 1200% or less, such as about 1100% or less, such as about 1000% or less, such as about 950% or less, such as about 900% or less, such as about 850% or less, such as about 800% or less, such as about 700% or less, such as about 600% or less, such as about 500% or less. The nominal strain at break may be determined in accordance with ISO 527-1/-2 (2012) at a temperature of about 23° C.
At least in part due to these beneficial properties of the thermoplastic copolyester elastomer, the resulting yarn may also exhibit certain desired properties that allow it to be used for various applications, such as textiles. In particular, the yarn as disclosed herein may provide stretch or elasticity and without intending to be limited by theory, such stretch/elasticity may contribute to the ability of the yarn to be utilized while minimizing yarn breakage. In this regard, the elongation at break of the yarn may be about 300% or more, such as about 325% or more, such as about 350% or more, such as about 375% or more, such as about 400% or more, such as about 450% or more, such as about 500% or more, such as about 600% or more, such as about 800% or more, such as about 1000% or more. The elongation at break may be about 2000% or less, such as about 1800% or less, such as about 1600% or less, such as about 1400% or less, such as about 1200% or less, such as about 1000% or less, such as about 900% or less, such as about 800% or less, such as about 700% or less, such as about 600% or less, such as about 550% or less, such as about 500% or less, such as about 475% or less, such as about 450% or less, such as about 425% or less, such as about 400% or less, such as about 375% or less. Furthermore, because the yarn may exhibit such a relatively high elongation at break, it may also generally be referred to as an elastic yarn. The elongation at break may be determined in accordance with ASTM D2653-07(2018) at a temperature of about 23° C.
In addition to the elongation at break, the yarn may also exhibit a desired strength as indicated by the tenacity. For instance, the tenacity may be about 0.7 grams per denier (g/d) or more, such as about 0.75 g/d or more, such as about 0.8 g/d or more, such as about 0.85 g/d or more, such as about 0.9 g/d or more, such as about 0.95 g/d or more, such as about 1 g/d or more, such as about 1.05 g/d or more, such as about 1.1 g/d or more, such as about 1.15 g/d or more, such as about 1.2 g/d or more, such as about 1.4 g/d or more, such as about 1.6 g/d or more, such as about 1.8 g/d or more, such as about 2 g/d or more, such as about 2.5 g/d or more, such as about 3 g/d or more, such as about 4 g/d or more, such as about 5 g/d or more. The tenacity may be about 10 g/d or less, such as about 8 g/d or less, such as about 6 g/d or less, such as about 5 g/d or less, such as about 4 g/d or less, such as about 3.5 g/d or less, such as about 3 g/d or less, such as about 2.5 g/d or less, such as about 2 g/d or less, such as about 1.8 g/d or less, such as about 1.6 g/d or less, such as about 1.4 g/d or less, such as about 1.2 g/d or less, such as about 1.15 g/d or less, such as about 1.1 g/d or less, such as about 1.05 g/d or less, such as about 1 g/d or less. The tenacity may be determined in accordance with ASTM D2653-07 (2017) at a temperature of about 23° C.
In addition, even with a relatively high elongation at break, the yarn may nonetheless exhibit a relatively low shrinkage. For instance, the shrinkage may be about 50% or less, such as about 40% or less, such as about 35% or less, such as about 30% or less, such as about 25% or less, such as about 20% or less, such as about 15% or less, such as about 10% or less, such as about 9% or less, such as about 8.5% or less, such as about 8% or less, such as about 7.5% or less, such as about 7% or less, such as about 6.5% or less, such as about 6% or less, such as about 5.5% or less, such as about 5% or less, such as about 4.5% or less, such as about 4% or less, such as about 3.5% or less, such as about 3% or less, such as about 2.5% or less. The shrinkage may be about 0% or more, such as about 0.1% or more, such as about 0.3% or more, such as about 0.5% or more, such as about 1% or more, such as about 1.5% or more, such as about 2% or more, such as about 2.5% or more, such as about 3% or more, such as about 3.5% or more, such as about 4% or more, such as about 4.5% or more, such as about 5% or more, such as about 5.5% or more, such as about 6% or more, such as about 6.5% or more, such as about 7% or more, such as about 7.5% or more, such as about 10% or more, such as about 15% or more, such as about 20% or more, such as about 25% or more. The shrinkage may be determined in accordance with ASTM D2259-02 (2016) (Section 6.6.1, Step 13, dry heat exposure at a temperature of about 120° C.).
Related, the yarn may have a recoverable stretch of at least about 75%, such as at least about 80%, such as at least about 85%, such as at least about 90%, such as at least about 93%, such as at least about 95%, such as at least about 100%, such as at least about 125%, such as at least about 150%, such as at least about 175%, such as at least about 200%, such as at least about 225%, such as at least about 250%. The recoverable stretch may be about 500% or less, such as about 450% or less, such as about 400% or less, such as about 350% or less, such as about 300% or less, such as about 250% or less, such as about 200% or less, such as about 150% or less, such as about 140% or less, such as about 130% or less, such as about 120% or less, such as about 110% or less, such as about 105% or less, such as about 100% or less. Accordingly, the yarn may recover rapidly and substantially to its original length when stretched to one and half times its original length (150%) and released. The recoverable stretch may be determined in accordance with ASTM D6720-07 (2018).
Various embodiments of the present disclosure will now be described in more detail.
In general, the yarn as disclosed herein is formed from one or more thermoplastic copolyester elastomers. In this regard, the one or more thermoplastic copolyester elastomers may be presented within a thermoplastic copolyester elastomer composition including the one or more thermoplastic copolyester elastomers and optionally one or more additives as defined herein and/or generally known in the art. However, it should be understood that in certain embodiments, the one or more thermoplastic copolyester elastomers may constitute the composition in its entirety (e.g., without the incorporation of one or more additives).
As indicated above, the thermoplastic copolyester elastomer composition includes one or more thermoplastic copolyester elastomers. The thermoplastic copolyester elastomer may be a thermoplastic copolyetherester elastomer and/or a thermoplastic copolyesterester elastomer. In one embodiment, the thermoplastic copolyester elastomer may be a thermoplastic copolyesterester elastomer. In one particular embodiment, the thermoplastic copolyester elastomer may be a thermoplastic copolyetherester elastomer.
As indicated above, the thermoplastic copolyester elastomer may be a copolyesterester elastomer. In general, a copolyesterester elastomer is a block copolymer containing (a) a hard polyester segment and (b) a soft polyester segment. Examples of hard polyester segments include, but are not limited to, polyalkylene terephthalates, poly(cyclohexanedicarboxylic acid cyclohexanemethanol), etc. and the like. Examples of soft polyester segments include, but are not limited to, aliphatic polyesters including, but not limited to, polybutylene adipate, polytetramethyladipate and polycaprolactone, etc.
The copolyesterester elastomer may contain one or more blocks of ester units of a high melting polyester and one or more blocks of ester units of a low melting polyester which are linked together through ester groups or urethane groups. Copolyesterester elastomers comprising urethane groups may be prepared by reacting the different polyesters in the molten phase, after which the resulting copolyesterester is reacted with a low molecular weight polyisocyanate. The polyisocyanate may be a diisocyanate or a triisocyanate. In particular, the polyisocyanate may be a diisocyanate, such as a paratoluene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate, and/or isophorone diisocyanate.
As indicated above, the thermoplastic copolyester elastomer may be a copolyetherester elastomer. In general, a copolyetherester elastomer may have a multiplicity of recurring long-chain ester units and short-chain ester units joined head-to-tail through ester linkages. The long-chain ester units can be represented by formula (A):
and the short-chain ester units can be represented by formula (B):
wherein
As used herein, the term “long-chain ester units” refers to the reaction product of a long-chain glycol with a dicarboxylic acid. The long chain glycols are polymeric glycols having terminal (or nearly terminal as possible) hydroxyl groups. In particular, suitable long-chain glycols include poly(alkylene oxide) glycols having terminal (or as nearly terminal as possible) hydroxyl groups and having a number average molecular weight of from about 400 to about 6000, such as from about 400 to about 3000, such as from about 600 to about 3000, such as from about 1000 to about 3000, such as from about 1000 to about 2000. In addition, the long-chain glycols may have a melting point of less than about 65° C., such as less than about 60° C., such as less than about 55° C., such as less than about 50° C. The long chain glycols are generally poly(alkylene oxide) glycols or glycol esters of poly(alkylene oxide) dicarboxylic acids. Preferred poly(alkylene oxide) glycols include poly(tetramethylene oxide) glycol, poly(trimethylene oxide) glycol, poly(propylene oxide) glycol (e.g., 1,2- or 1,3-propylene oxide), poly(ethylene oxide) glycol, poly(hexamethylene oxide) glycol, poly(heptamethylene oxide) glycol, poly(octamethylene oxide) glycol, poly(nonamethylene oxide) glycol, and poly(1,2-butylene oxide) glycol, copolymer glycols of these alkylene oxides, and block copolymers such as ethylene oxide-capped poly(propylene oxide) glycol. In addition, it should be understood that a mixture of two or more of these glycols may also be utilized. Also, any substituent groups can be present which do not interfere with polymerization of the compound with glycol(s) or dicarboxylic acid(s), as the case may be. The hydroxyl functional groups of the long chain glycols which react to form the copolyester can be terminal groups to the extent possible. The terminal hydroxyl groups can be placed on end capping glycol units different from the chain (e.g., ethylene oxide end groups on poly(propylene oxide glycol). Long chain ester units of Formula (A) may also be referred to as “soft segments” of a copolyetherester elastomer.
As used herein, the term “short-chain ester units” refers to low molecular weight compounds or polymer chain units having a number average molecular weight of less than about 550, such as less than about 525, such as less than about 500, such as less than about 475, such as less than about 450. They can generally be made by reacting a low molecular weight diol or a mixture of diols (molecular weight below about 250, such as below about 225, such as below about 200, such as below about 175, such as below about 150) with a dicarboxylic acid to form ester units represented by Formula (B) above. Short chain ester units of Formula (B) may also be referred to as “hard segments” of the copolyetherester polymer.
Included among the low molecular weight diols which react to form short-chain ester units for preparing copolyesters are acyclic, alicyclic and aromatic dihydroxy compounds. These compounds include diols with about 2 to about 15 carbon atoms, such as about 2 to about 8 carbon atoms, such as about 2 to about 6 carbon atoms, such as ethylene, propylene, isobutylene, tetramethylene, 1,4-pentamethylene, 2,2-dimethyltrimethylene, hexamethylene and decamethylene glycols, dihydroxycyclohexane, cyclohexane dimethanol, resorcinol, hydroquinone, 1,5-dihydroxynaphthalene, and the like. In particular, the diol may be an aliphatic diol, such as 1,4-butanediol, ethylene glycol, 1,3-propanediol, cyclohexanedimethanol, and/or hexamethylene glycol. For instance, the diol may be ethylene glycol, 1,4 butanediol, 1,3-propane diol, or a combination thereof. In particular, the diol may be 1,4 butanediol, 1,3-propane diol, or a combination thereof. In one embodiment, 1,4-butanediol is preferred. In another embodiment, ethylene glycol is preferred. In another further embodiment, 1,3-propanediol is preferred. In one embodiment, 1,4-butanediol may be provided as a mixture with ethylene glycol, 1,3-propanediol, cyclohexanedimethanol, and/or hexamethylene glycol. Included among the bisphenols which can be used are bis(p-hydroxy) diphenyl, bis(p-hydroxyphenyl)methane, and bis(p-hydroxyphenyl)propane. Equivalent ester-forming derivatives of diols are also useful (e.g., ethylene oxide or ethylene carbonate can be used in place of ethylene glycol or resorcinol diacetate can be used in place of resorcinol).
As used herein, the term “diols” includes equivalent ester-forming derivatives such as those mentioned. However, the molecular weight requirements refer to the corresponding diols and not their derivatives.
The dicarboxylic acids that can react with the aforementioned long-chain glycols and low molecular weight diols to produce the copolyetheresters may include aliphatic, cycloaliphatic or aromatic dicarboxylic acids of a low molecular weight (e.g., having a molecular weight of less than about 300, such as less than about 275, such as less than about 250, such as less than about 225). The term “dicarboxylic acids” as used herein includes functional equivalents of dicarboxylic acids that have two carboxyl functional groups that perform substantially like dicarboxylic acids in reaction with glycols and diols in forming thermoplastic copolyetherester elastomers. These equivalents include esters and ester-forming derivatives such as acid halides and anhydrides. The molecular weight requirement pertains to the acid and not to its equivalent ester or ester-forming derivative.
Thus, an ester of a dicarboxylic acid having a molecular weight greater than 300 or a functional equivalent of a dicarboxylic acid having a molecular weight greater than 300 are also suitable, provided the corresponding acid has a molecular weight below about 300 or the aforementioned molecular weights. The dicarboxylic acid can contain any substituent groups or combinations that do not substantially interfere with thermoplastic copolyetherester elastomer formation and use of the thermoplastic copolyetherester elastomer in the composition.
As used herein, the term “aliphatic dicarboxylic acids” refers to carboxylic acids having two carboxyl groups, each attached to a saturated carbon atom. If the carbon atom to which the carboxyl group is attached is saturated and is in a ring, the acid is cycloaliphatic. Aliphatic or cycloaliphatic acids having conjugated unsaturation often may not be used because of homopolymerization. However, some unsaturated acids, such as maleic acid, may be used.
As used herein, the term “aromatic dicarboxylic acids” refers to dicarboxylic acids having two carboxyl groups each attached to a carbon atom in a carbocyclic aromatic ring structure. It is not necessary that both functional carboxyl groups be attached to the same aromatic ring and where more than one ring is present, they can be joined by aliphatic or aromatic divalent radicals or divalent radicals such as —O— or —SO2—.
Representative aliphatic and cycloaliphatic acids that can be used include, but are not limited to, sebacic acid; 1,3-cyclohexane dicarboxylic acid; 1,4-cyclohexane dicarboxylic acid; adipic acid; glutaric acid; succinic acid; 4-cyclohexane-1,2-dicarboxylic acid; 2-ethylsuberic acid; cyclopentanedicarboxylic acid, decahydro-1,5-naphthylene dicarboxylic acid; 4,4′-bicyclohexyl dicarboxylic acid; decahydro-2,6-naphthylene dicarboxylic acid; 4,4′-methylenebis (cyclohexyl) carboxylic acid; 3,4-furan dicarboxylic acid; and mixtures thereof. In one embodiment, the preferred acid may include a cyclohexane dicarboxylic acid and/or adipic acid.
Representative aromatic dicarboxylic acids that can be used include, but are not limited to, phthalic, terephthalic and isophthalic acids; bibenzoic acid; substituted dicarboxy compounds with two benzene nuclei such as bis(p-carboxyphenyl) methane; p-oxy-1,5-naphthalene dicarboxylic acid; 2,6-naphthalene dicarboxylic acid; 2,7-naphthalene dicarboxylic acid; 4,4′-sulfonyl dibenzoic acid and C1-C12 alkyl and ring substitution derivatives thereof, such as halo, alkoxy, and aryl derivatives; and mixtures thereof. Hydroxy acids such as p-(beta-hydroxyethoxy) benzoic acid can also be used, provided an aromatic dicarboxylic acid is also used.
In one embodiment, an aromatic dicarboxylic acid is preferred for preparing thermoplastic copolyetherester elastomers. Among the aromatic dicarboxylic acids, those with 8 to 16 carbon atoms, such as 8 to 12 carbon atoms, such as 8 to 10 carbon atoms may be preferred. In particular, the aromatic dicarboxylic acid may include terephthalic acid, phthalic acid, and/or isophthalic acid. In particular, the aromatic dicarboxylic acid may include terephthalic acid, isophthalic acid, or a combination thereof. In one embodiment, the aromatic acid may include terephthalic acid alone or with a mixture of phthalic acid and/or isophthalic acid.
When a mixture of two or more dicarboxylic acids is used to prepare the copolyetherester, isophthalic acid may be a preferred second dicarboxylic acid in one embodiment. For instance, isophthalic acid may be provided in a mixture with terephthalic acid. In this regard, the amount of copolymerized isophthalate residues in the copolyetherester may be less than 35 mole %, such as less than 30 mole %, such as less than 25 mole %. Similarly, copolymerized isophthalate residues in the copolyetherester may be less than 35 wt. %, such as less than 30 wt. %, such as less than 25 wt. %, based on the total weight of copolymerized dicarboxylic acid residues —(—C(O)RC(O)—)— in the copolyetherester. The remainder of the phenylene diradicals may be derived from terephthalic acid based on the total number of moles of copolymerized dicarboxylic acid residues —(—C(O)RC(O)—)— in the copolyetherester.
In addition, in one embodiment, at least about 70 mol. % of the groups represented by R in Formulae (A) and (B) above may be 1,4-phenylene radicals and at least about 70 mol. % of the groups represented by D in Formula (B) above may be 1,4-butylene radicals and the sum of the percentages of R groups which are not 1,4-phenylene radicals and D groups which are not 1,4-butylene radicals may not exceed 30 mol. %.
For example, the copolyetherester may have hard segments composed of polybutylene terephthalate and about 5 wt. % to about 80 wt. %, such as about 5 wt. % to about 75 wt. %, such as about 10 wt. % to about 70 wt. %, such as about 10 wt. % to about 60 wt. %, such as about 20 wt. % to about 60 wt. %, of soft segments composed of the reaction product of a polyether glycol and an aromatic diacid. The polyether blocks may be derived from polytetramethylene glycol. Complementarily, the fraction of hard segments may be about 20 wt. % to about 95 wt. %, such as about 20 wt. % to about 90 wt. %, such as about 30 wt. % to about 90 wt. %, such as about 40 wt. % to about 90 wt. %, such as about 40 wt. % to about 80 wt. %.
While not limited, preferred thermoplastic copolyetherester elastomers include those prepared from monomers comprising the following: (A) (1) poly(tetramethylene oxide) glycol, (2) a dicarboxylic acid selected from isophthalic acid, terephthalic acid or a mixture thereof, and (3) a diol selected from 1,4-butanediol, 1,3-propanediol or a mixture thereof; (B) (1) poly(trimethylene oxide) glycol, (2) a dicarboxylic acid selected from isophthalic acid, terephthalic acid or a mixture thereof, and (3) a diol selected from 1,4-butanediol, 1,3-propanediol or a mixture thereof; or (C) (1) ethylene oxide-capped poly(propylene oxide) glycol; (2) a dicarboxylic acid selected from isophthalic acid, terephthalic acid or a mixture thereof; and (3) a diol selected from 1,4-butanediol, 1,3-propanediol or a mixture thereof.
Preferably, the thermoplastic copolyetherester elastomers may be prepared from esters or mixtures of esters of terephthalic acid or isophthalic acid, 1,4-butanediol and poly(tetramethylene ether) glycol, poly(trimethylene ether) glycol, or ethylene oxide-capped polypropylene oxide glycol or may be prepared from esters of terephthalic acid (e.g., dimethylterephthalate), 1,4-butanediol and poly(ethylene oxide) glycol). More preferably, the thermoplastic copolyetherester elastomers may be prepared from esters of terephthalic acid (e.g., dimethylterephthalate), 1,4-butanediol and poly(tetramethylene ether) glycol.
For instance, in one particular embodiment, the thermoplastic copolyetherester elastomer may have the following formula: -[4GT]x-[BT]y-, wherein 4G is the residue of butylene glycol, such as 1,4-butane diol, B is the residue of poly(tetramethylene ether glycol) and T is terephthalate, and wherein x is from about 0.60 to about 0.99 and y is from about 0.01 to about 0.40.
In one aspect, the thermoplastic copolyetherester elastomer can be a block copolymer of polybutylene terephthalate and polyether segments and can have a structure as follows:
wherein a and b are integers and can vary from 2 to 10,000. The ratio between hard segments and soft segments in the block copolymer as described above can be varied in order to vary the properties of the elastomer.
In general, the thermoplastic copolyetherester elastomer preferably comprises about 1 wt. % or more, such as about 5 wt. % or more, such as about 10 wt. % or more, such as about 20 wt. % or more, such as about 25 wt. % or more, such as about 30 wt. % or more, such as about 35 wt. % or more, such as about 40 wt. % or more, such as about 45 wt. % or more, such as about 50 wt. % or more, such as about 55 wt. % or more of copolymerized residues of long-chain ester units corresponding to Formula (A) above (hard segments). The thermoplastic copolyetherester elastomer preferably comprises about 85 wt. % or less, such as about 80 wt. % or less, such as about 75 wt. % or less, such as about 70 wt. % or less, such as about 65 wt. % or less, such as about 60 wt. % or less of copolymerized residues of long-chain ester units corresponding to Formula (A) above (hard segments).
In general, the thermoplastic copolyetherester elastomer preferably comprises about 10 wt. % or more, such as about 20 wt. % or more, such as about 25 wt. % or more, such as about 30 wt. % or more, such as about 35 wt. % or more, such as about 40 wt. % or more, such as about 45 wt. % or more, such as about 50 wt. % or more of copolymerized residues of short-chain ester units corresponding to Formula (B) above (soft segments). The thermoplastic copolyetherester elastomer preferably comprises about 99 wt. % or less, such as about 95 wt. % or less, such as about 90 wt. % or less, such as about 85 wt. % or less, such as about 80 wt. % or less, such as about 75 wt. % or less, such as about 70 wt. % or less, such as about 65 wt. % or less, such as about 60 wt. % or less, such as about 55 wt. % or less of copolymerized residues of short-chain ester units corresponding to Formula (B) above (soft segments).
In one embodiment, the thermoplastic copolyetherester elastomer may comprise only copolymerized residues of long-chain ester units corresponding to Formula (A) above and short-chain ester units corresponding to Formula (B) above. In this regard, the weight percentages of the copolymerized units of Formula (A) and Formula (B) in the copolyetherester may be complementary. That is, the sum of the weight percentages of the copolymerized units of Formula (A) and Formula (B) may be 100 wt. %. Similarly, the mole percentages of the R groups in the copolymerized units of Formula (A) and Formula (B) in the copolyetherester copolymer may be complementary. That is, the sum of the mole percentages of the R groups in the copolymerized units of Formula (A) and Formula (B) may be 100 mol %.
Furthermore, it should be understood that a mixture of two or more thermoplastic copolyester elastomers, in particular thermoplastic copolyetherester elastomers, can be used. In one embodiment, the composition may contain one thermoplastic copolyester elastomer as defined herein. In other embodiments, the composition may include a mixture of thermoplastic copolyester elastomers. For instance, more than one thermoplastic copolyester elastomer, such as two or three thermoplastic copolyester elastomers, may be utilized in the composition.
Specifically, regarding the thermoplastic copolyester elastomers, in particular a mixture of thermoplastic copolyetherester elastomers, each elastomer used need not on an individual basis come within the values set forth above for the elastomers. In this regard, the mixture of two or more thermoplastic copolyetherester elastomers may conform to the values described herein for the copolyetheresters on a weighted average basis, however. For example, in a mixture that contains equal amounts of two thermoplastic copolyetherester elastomers, one thermoplastic copolyetherester elastomer can contain 60 weight percent short-chain ester units and the other resin can contain 30 weight percent short-chain ester units for a weighted average of 45 weight percent short-chain ester units.
Regarding the properties of the thermoplastic copolyester elastomer, it may be desired to have a melt flow that can allow it to be processed in a relatively easy manner for the formation of a filament and a yarn as disclosed herein. In this regard, the thermoplastic copolyester elastomer may exhibit a relatively low melt viscosity as indicated by the melt flow rate. For instance, the melt flow rate of the thermoplastic copolyester elastomer may be about 0.5 g/10 min or more, such as about 1 g/10 min or more, such as about 2 g/10 min or more, such as about 3 g/10 min or more, such as about 4 g/10 min or more, such as about 5 g/10 min or more, such as about 8 g/10 min or more, such as about 10 g/10 min or more, such as about 15 g/10 min or more. The melt flow rate may be about 40 g/10 min or less, such as about 35 g/10 min or less, such as about 30 g/10 min or less, such as about 25 g/10 min or less, such as about 20 g/10 min or less, such as about 15 g/10 min or less, such as about 10g/10 min or less, such as about 8 g/10 min or less, such as about 6 g/10 min or less, such as about 5 g/10 min or less, such as about 4 g/10 min or less, such as about 3 g/10 min or less. The melt flow rate may be determined at 220° C. under a 2.16 kg load according to ISO1133.
The thermoplastic copolyester elastomer may also have a relatively low melting temperature. For instance, the melting temperature may be about 100° C. or more, such as about 110° C. or more, such as about 130° C. or more, such as about 150° C. or more, such as about 170° C. or more, such as about 190° C. or more, such as about 200° C. or more, such as about 220° C. or more, such as about 240° C. or more. The melting temperature may be about 300° C. or less, such as about 280° C. or less, such as about 250° C. or less, such as about 230° C. or less, such as about 210° C. or less, such as about 200° C. or less, such as about 180° C. or less, such as about 160° C. or less, such as about 140° C. or less, such as about 120° C. or less. The melting temperature may be determined using means known in the art, such as differential scanning calorimetry in accordance with ISO 11357-1:2023 at a rate of 10° C./min.
In addition, the glass transition temperature of the thermoplastic copolyester elastomer, in particular the thermoplastic copolyester elastomer, may be within a particular range. For instance, the glass transition temperature may be about −80° C. or more, such as about −70° C. or more, such as about −60° C. or more, such as about −50° C. or more, such as about −40° C. or more, such as about −30° C. or more. The glass transition temperature may be about 0° C. or less, such as about −5° C. or less, such as about −10° C. or less, such as about −20° C. or less, such as about −30° C. or less, such as about −40° C. or less. Also, the glass transition temperature of the hard segment of the thermoplastic copolyester elastomer may be within a particular range. For instance, the glass transition temperature of the hard segment may be about 30° C. or more, such as about 35° C. or more, such as about 40° C. or more, such as about 45° C. or more, such as about 50° C. or more, such as about 55° C. or more, such as about 60° C. or more, such as about 65° C. or more, such as about 70° C. or more, such as about 75° C. or more, such as about 80° C. or more. The glass transition temperature may be about 150° C. or less, such as about 140° C. or less, such as about 130° C. or less, such as about 120° C. or less, such as about 110° C. or less, such as about 100° C. or less, such as about 90° C. or less, such as about 80° C. or less, such as about 70° C. or less, such as about 60° C. or less, such as about 55° C. or less, such as about 50° C. or less, such as about 45° C. or less, such as about 40° C. or less, such as about 35° C. or less, such as about 30° C. or less. The glass transition temperature may be determined using means known in the art, such as differential scanning calorimetry in accordance with ISO 11357-1:2023 at a rate of 10° C./min.
Further, the thermoplastic copolyester elastomer may have a particular density. For instance, the density be about 1 g/cm3 or more, such as about 1.03 g/cm3 or more, such as about 1.05 g/cm3 or more, such as about 1.08 g/cm3 or more, such as about 1.1 g/cm3 or more, such as about 1.15 g/cm3 or more, such as about 1.2 g/cm3 or more, such as about 1.3 g/cm3 or more. The thermoplastic copolyester elastomer may have a density of about 2 g/cm3 or less, such as about 1.8 g/cm3 or less, such as about 1.6 g/cm3 or less, such as about 1.4 g/cm3 or less, such as about 1.3 g/cm3 or less, such as about 1.25 g/cm3 or less, such as about 1.2 g/cm3 or less, such as about 1.18 g/cm3 or less, such as about 1.15 g/cm3 or less, such as about 1.12 g/cm3 or less, such as about 1.1 g/cm3 or less. The density may be determined in accordance with ISO 1183-1:2019.
The thermoplastic copolyester elastomer composition may generally comprise about 10 wt. % or more, such as about 15 wt. % or more, such as about 20 wt. % or more, such as about 25 wt. % or more, such as about 30 wt. % or more, such as about 35 wt. % or more, such as about 40 wt. % or more, such as about 50 wt. % or more, such as about 60 wt. % or more, such as about 70 wt. % or more, such as about 80 wt. % or more, such as about 90 wt. % or more, such as about 95 wt. % or more of the one or more thermoplastic copolyester elastomers. The thermoplastic copolyester elastomer composition may comprise about 100 wt. % or less, such as about 95 wt. % or less, such as about 90 wt. % or less, such as about 80 wt. % or less, such as about 70 wt. % or less, such as about 60 wt. % or less, such as about 50 wt. % or less of the one or more thermoplastic copolyester elastomers.
In addition to the thermoplastic copolyester elastomer, the thermoplastic copolyester elastomer composition may optionally further comprise one or more additives. In this regard, in one embodiment, the thermoplastic copolyester elastomer composition may further comprise one or more additives. For instance, the additives may include those typically utilized in the art in order to provide a resulting material having the desired properties. These additives may include, but are not limited to, fillers, reinforcing agents, process aids, plasticizers, stabilizers (e.g., heat stabilizers; UV light stabilizers; metal deactivators; antioxidants such as phenolic, phosphite, and/or amine containing antioxidants; etc.), viscosity modifiers, nucleating agents, lubricants, flow enhancing additives, flame retardants (e.g., phosphates such as polyphosphates, pyrophosphates, etc.; phosphinates; etc.), impact modifiers, antistatic agents, antimicrobial agents, colorants, pigments, etc.
When utilized, the respective additive may be present in the thermoplastic copolyester elastomer composition in an amount of about 0.01 wt. % or more, such as about 0.05 wt. % or more, such as about 0.1 wt. % or more, such as about 0.2 wt. % or more, such as about 0.3 wt. % or more, such as about 0.5 wt. % or more, such as about 0.8 wt. % or more, such as about 1 wt. % or more, such as about 1.5 wt. % or more, such as about 2 wt. % or more, such as about 2.5 wt. % or more, such as about 3 wt. % or more, such as about 5 wt. % or more based on the weight of the thermoplastic copolyester elastomer composition. The respective additive may be present in the thermoplastic copolyester elastomer composition in an amount of about 20 wt. % or less, such as about 15 wt. % or less, such as about 12 wt. % or less, such as about 10 wt. % or less, such as about 8 wt. % or less, such as about 6 wt. % or less, such as about 5 wt. % or less, such as about 4 wt. % or less, such as about 3 wt. % or less, such as about 2.8 wt. % or less, such as about 2.5 wt. % or less, such as about 2.3 wt. % or less, such as about 2 wt. % or less, such as about 1.8 wt. % or less, such as about 1.6 wt. % or less, such as about 1.4 wt. % or less, such as about 1.2 wt. % or less, such as about 1 wt. % or less, such as about 0.8 wt. % or less, such as about 0.5 wt. % or less based on the weight of the thermoplastic copolyester elastomer composition. In another embodiment, the aforementioned weight percentages may be based on the weight of the one or more thermoplastic copolyester elastomers.
In one embodiment, the thermoplastic copolyester elastomer composition may comprise one or more non-elastomeric polymers. In general, any non-elastomeric polymer may be utilized. For instance, the non-elastomeric polymer may be a thermoplastic polymer, a thermoset polymer, or a mixture thereof. In one embodiment, the non-elastomeric polymer may be a thermoplastic polymer. In another embodiment, the non-elastomeric polymer may be a thermoset polymer.
In this regard, the non-elastomeric polymer may include, but is not limited to, a poly(meth)acrylic, a polyacrylate, a polystyrene, a polyolefin (e.g., a polyethylene such as high density polyethylene, low density polyethylene, linear low density polyethylene, ultralow density polyethylene); a polypropylene, etc.), a polyurethane, a polyurea, an epoxy resin, a polyester (e.g., poly(ethylene terephthalate), poly(1,3-propyl terephthalate), poly(1,4-butylene terephthalate), PETG, poly(ethylene-co-1,4-cyclohexanedimethanol terephthalate)), an alkyd resin, a polyamide (e.g., nylons, nylon 6, nylon 46, nylon 66, nylon 612), a polyamideimide, a polyvinyl, a phenoxy resin, an amino resin, a melamine, a polyether, a polyvinyl acetal, a polyvinyl formal, a poly(vinyl butyrate), a polyacetylene, a polyether, a silicone resin, an ABS resin, a polysulfone, a polyamine sulfone, a polyether sulfone, a polyphenylene sulfone, a polyvinyl chloride, a polyvinylidene chloride, a polyvinyl acetate, a polyvinyl alcohol, a polyvinyl carbazole, a butyral, a polyphenylene oxide, a polypyrrole, a polyparaphenylene, a cellulose derivative, a polytetrafluoroethylene, a polytrifluoroethylene, a polyvinylidene fluoride, a novolac, a poly(cresol), a polycarbonate, a polysulfide, a poly(phenylene sulfide), a poly(2,6-dimethylphenylene oxide), etc. and the like. It should be understood that such non-elastomeric polymer may also include modifications to any of the foregoing as well as copolymers thereof. In addition, it should also be understood that the composition may include a combination of two or more of the aforementioned. In one embodiment, the non-elastomeric polymer(s) may be miscible with the thermoplastic copolyester elastomer copolymer and/or the thermoplastic copolyester elastomer polymer composition.
When non-elastomeric polymer(s) are present in the thermoplastic copolyester elastomer composition, they may be present in any amount. However, in one embodiment, they may be present in an amount less than the thermoplastic copolyester elastomer.
The non-elastomeric polymer(s) may be present in the thermoplastic copolyester elastomer composition in an amount of about 1 wt. % or more, such as about 2 wt. % or more, such as about 5 wt. % or more, such as about 10 wt. % or more, such as about 15 wt. % or more, such as about 20 wt. % or more, such as about 25 wt. % or more, such as about 30 wt. % or more, such as about 35 wt. % or more, such as about 40 wt. % or more based on the total weight of the thermoplastic copolyester elastomer composition. The non-elastomeric polymer(s) may be present in an amount of about 60 wt. % or less, such as about 50 wt. % or less, such as about 40 wt. % or less, such as about 35 wt. % or less, such as about 30 wt. % or less, such as about 25 wt. % or less, such as about 20 wt. % or less, such as about 15 wt. % or less, such as about 10 wt. % or less, such as about 8 wt. % or less, such as about 5 wt. % or less based on the total weight of the thermoplastic copolyester elastomer composition.
The thermoplastic copolyester elastomer composition described herein can be processed using techniques generally known in the art. For instance, the components (thermoplastic copolyester elastomer and optional additives) may be melt-mixed (also referred to as melt-blended). Utilizing such an approach, the components may be well-dispersed throughout the composition. Furthermore, the components may be provided in a single-step addition or in a step-wise manner. The processing may be conducted in a chamber, which may be any vessel that is suitable for blending the composition under the necessary temperature and shearing force conditions. In this respect, the chamber may be a mixer, such as a Banbury™ mixer or a Brabender™ mixer, an extruder, such as a co-rotating extruder, a counter-rotating extruder, or a twin-screw extruder, a co-kneader, such as a Buss® kneader, etc. Upon completion of the mixing/blending, the composition may be milled, chopped, extruded, pelletized, or processed by any other desirable technique. In certain instances, the components may be melt-blended and directly fed to a downstream operation, such as a spinneret for forming filaments and yarns as disclosed herein. In particular, once formed, the thermoplastic copolyester elastomer composition may be utilized to form filaments and yarns as further described herein.
As indicated herein, the thermoplastic copolyester elastomer composition is suitable for forming filaments and corresponding yarns. While the thermoplastic copolyester elastomer composition may be utilized to form short fiber yarns, in one particular embodiment, the thermoplastic copolyester elastomer composition is utilized to form continuous filaments and corresponding yarns. In particular, the properties of the thermoplastic copolyester elastomer allow it to be processed to form filaments at speeds and conditions as disclosed herein and thereafter allow the filaments to be processed to form yarns and resulting articles.
The filaments of the present disclosure can be made using conventional processes known in the art. For example, these processes may include general steps such as spinning and optionally drawing the thermoplastic copolyester elastomer composition, including the thermoplastic copolyester elastomer, into a filament. The filaments may also be treated mechanically and/or chemically (e.g., via finishes) to impart desirable characteristics such as strength, elasticity, heat resistance, feel, etc. depending on the desired properties and characteristics of the resulting article made from the filaments and yarns.
In one particular embodiment, the filaments may be formed via melt spinning. Accordingly, the filaments may be melt spun filaments. Generally, melt spinning includes heating the thermoplastic copolyester elastomer composition including the thermoplastic copolyester elastomer to form a melt (also referred to as an elastomer melt) wherein such melting can be conducted by heating the thermoplastic copolyester elastomer against a heated surface. As an example, the thermoplastic copolyester elastomer may be heated in a mixer or an extruder and thereafter provided or metered to a spinneret. The temperature of operation may correspond to the melting temperature of the thermoplastic copolyester elastomer; for instance, the temperature may be relatively higher than the melting temperature of the thermoplastic copolyester elastomer in order to allow for the formation of an elastomer melt. Regardless, the operation temperature may be within the ranges of the melting temperature of the thermoplastic copolyester elastomer as defined above.
The spinneret includes a plurality of orifices or capillaries having a particular size and design that allows for the formation of a filament having the desired configuration and cross-section. Accordingly, this process allows filaments of various sizes and cross sections to be formed, including filaments having, for example, round, elliptical, square, rectangular, lobed or dog-boned cross sections, etc. The plate with the particular design utilized in making the filaments can be formed using means known in the art, such as laser cutting, micro-hole drilling, laser micro machining, and micro wire EDM. In addition, it should be understood that pre-coalescence (e.g., forming the desired cross-section through the spinneret capillaries) or post-coalescence (e.g., allowing melt to coalesce below the spinneret face for forming a desired cross-section) spinnerets can be used.
In this regard, any monofilaments formed from the thermoplastic copolyester elastomer composition may be a pre-coalesced monofilament or a post-coalesced monofilament. In one particular embodiment, the monofilament may be a post-coalesced monofilament wherein individual filaments coalesce upon exiting or being withdrawn from the spinneret. To allow for such coalescence, the filaments may still be at a temperature greater than the melting temperature of the thermoplastic copolyester elastomer thereby allowing such filaments to coalesce (or fuse) for formation of the monofilament. In addition, such monofilaments, regardless of whether pre-coalesced or post-coalesced, may also be utilized for forming any multifilament yarns. Regardless, the multifilaments of the present disclosure are not coalesced or fused. In this regard, the monofilaments that make up the multifilament yarn are adhered and contact each other at a temperature below the melting temperature of the thermoplastic copolyester elastomer such that they may not have the ability to coalesce or fuse. Such monofilaments that make up the multifilament yarn may be adhered and contact each other wherein the filaments are at a temperature greater than the glass transition temperature of the thermoplastic copolyester elastomer. In this regard, the monofilaments may, without intending to be limited by theory, have a general tackiness allowing for such adhesion among monofilaments of the multifilament yarn.
Once extruded through the spinneret, the filaments may be quenched. For instance, the filaments can be contacted with a non-reactive gas stream (e.g., air) or a liquid (e.g., water) to assist in solidifying the filaments. As an example, a filament may be quenched while traversing in a general vertical direction using a non-reactive gas stream, such as air. In another embodiment, a filament may be quenched while traversing in a relatively horizontal direction through a liquid. In addition, in one embodiment, additional quenching may not be necessary and sufficient quenching may be conducted based on ambient conditions. Thereafter, the filaments are collected downstream from the spinneret using a guide and can be taken up by a roller or a plurality of rollers.
The thermoplastic copolyester elastomer can be spun at speeds of from about 200 to about 6000 meters per minute (m/min), depending on the desired filament size. When forming the filaments, the spinning speed may be at least about 200 m/min, such as at least about 400 m/min, such as at least about 500 m/min, such as at least about 600 m/min, such as at least about 800 m/min, such as at least about 1000 m/min, such as at least about 2000 m/min. The spinning speed may be about 6000 m/min or less, such as about 5000 m/min or less, such as about 4000 m/min or less, such as about 3000 m/min or less, such as about 2500 m/min or less, such as about 2000 m/min or less, such as about 1800 m/min or less, such as about 1600 m/min or less, such as about 1400 m/min or less, such as about 1200 m/min or less, such as about 1000 m/min or less.
In addition, a finish may be applied to the filaments. The finish may be applied for facilitating spinning and/or subsequent processing. For instance, the finish may be applied to impart lubrication thereby minimizing friction. The finish generally includes an oil (finish oil). In this regard, the finish oil may include, but is not limited to, a silicone oil, a mineral oil, an ester oil, and the like as well as mixtures thereof. In one embodiment, the finish oil may include a silicone oil. In another embodiment, the finish oil may include a mineral oil. In a further embodiment, the finish oil may include an ester oil. However, it should be understood that other finish oils utilized for thermoplastic copolyester elastomers may also be utilized. In addition, the finish may also include other additives generally utilized in the art. In this regard, the finish may include a salt of a fatty acid, in particular a metal salt of a fatty acid. For instance, the fatty acid salt may be a stearate in one embodiment. Accordingly, these additives within the finish may include, but are not limited to, sodium palmitate, sodium stearate, magnesium stearate, potassium stearate, potassium palmitate, potassium myristate, sodium myristate, calcium stearate, calcium laurate, zinc stearate, and mixtures thereof.
Such application of finish may be conducted before drawing an undrawn filament, if drawing such filament. In addition, it may be done after quenching. In one embodiment, such application may be conducted during quenching; in such instance, the filament and/or yarn may have a crimp, such as a helical crimp.
The finish may be provided on the yarns in a particular amount. For instance, the finish on yarn may be about 1 wt. % or more, such as about 2 wt. % or more, such as about 3 wt. % or more, such as about 4 wt. % or more, such as about 5 wt. % or more, such as about 6 wt. % or more, such as about 7 wt. % or more, such as about 8 wt. % or more, such as about 9 wt. % or more based on the total weight of the yarn. The finish on yarn may be about 20 wt. % or less, such as about 18 wt. % or less, such as about 16 wt. % or less, such as about 14 wt. % or less, such as about 12 wt. % or less, such as about 11 wt. % or less, such as about 10 wt. % or less, such as about 9 wt. % or less, such as about 8 wt. % or less, such as about 7 wt. % or less, such as about 6 wt. % or less, such as about 5 wt. % or less based on the total weight of the yarn. In addition, the finish may be provided on at least about 50% of the surface area of the filaments. For instance, the finish may be provided on at least about 50%, such as at least about 55%, such as at least about 60%, such as at least about 65%, such as at least about 70%, such as at least about 75%, such as at least about 80%, such as at least about 85%, such as at least about 90%, such as at least about 95% of the surface area of the filaments. Without intending to be limited by theory, such a finish may assist with cohesion of the filaments within a multifilament yarn. The finish on yarn can be determined using techniques known in the art, in particular by monitoring the speed of the filaments and the metered amount of the finish on the filaments.
Following extrusion from the spinneret, the filament may be drawn. The drawing may assist with achieving desirable properties, such as increasing amorphous orientation, shrinkage, modulus, and/or strength. However, it should be understood that in certain embodiments, drawing may not be conducted such that the filament produced is an undrawn filament. In such embodiments, the filament may still nonetheless have certain desirable properties. When conducted, the drawing can be done in combination with take-up by using a series of rollers or pins, some of which may be generally heated, or it can be done as a separate stage in the process of the filament formation. If heated, the drawing can be carried out at about 15° C.-150° C., such as from about 15° C.-130° C., such as from about 15° C.-100° C., such as from about 15° C.-80° C., such as from about 15° C.-60° C., such as from about 15° C.-40° C.
The godet roll speed, typically between a feed roll and a winding roll and which may be utilizing for drawing under certain conditions, may be from about 200 to about 6000 meters per minute (m/min). For instance, the speed may be at least about 200 m/min, such as at least about 400 m/min, such as at least about 500 m/min, such as at least about 600 m/min, such as at least about 800 m/min, such as at least about 1000 m/min, such as at least about 1250 m/min, such as at least about 1500 m/min, such as at least about 1750 m/min, such as at least about 2000 m/min. The speed may be about 6000 m/min or less, such as about 5000 m/min or less, such as about 4000 m/min or less, such as about 3000 m/min or less, such as about 2750 m/min or less, such as about 2500 m/min or less, such as about 2250 m/min or less, such as about 2000 m/min or less, such as about 1800 m/min or less, such as about 1600 m/min or less, such as about 1400 m/min or less, such as about 1200 m/min or less, such as about 1000 m/min or less.
The filaments may be drawn at any desired draw ratio depending on the desired properties, short of that which interferes with processing by breaking a filament. In this regard, the filaments may be drawn from 0× to about 6×, such as from about 0.9× to about 6×, such as from about 1.1× to about 6×. For instance, the filaments may be drawn at 0× or more, such as at least about 0.2×, such as at least about 0.3×, such as at least about 0.5×, such as at least about 0.7×, such as at least about 0.9×, such as at least about 1.1×, such as at least bout 1.2×, such as at least about 1.3×, such as at least about 1.4×, such as at least about 1.5×, such as at least about 1.8×, such as at least about 2×, such as at least about 2.2×, such as at least about 2.4×, such as at least about 2.5×. The filaments may be drawn about 5× or less, such as about 4.5× or less, such as about 4× or less, such as about 3.5× or less, such as about 3× or less, such as about 2.8× or less, such as about 2.6× or less, such as about 2.4× or less, such as about 2.2× or less, such as about 2× or less. Such drawing may be conducted in a single step draw in one embodiment. In another embodiment, however, the filaments may not be drawn.
The resulting filament is also amenable to further processing through the use of additional processing equipment, or it may be used directly in applications requiring a continuous filament and/or yarn. Regarding further processing, the filament subsequently may be converted to a textured yarn through known false twist texturing conditions or other processes. It may also be desirable to increase the surface area of the filament to provide a softer feel and to enhance the ability of the filaments to breathe, thereby providing better insulation and water retention in the case of textiles. To increase the surface area, the filament may be crimped or twisted, such as by a false twist method, an air jet, an edge crimp, a gear crimp, a stuffer box, etc. for example. In the case of an elastomeric yarn, a “bulking” type process to heat the yarn with minimal tension may also be performed to allow the yarn to relax and shrink, which may increase the elongation to break and thermal stability by heat history of the yarn. The method utilized may be dictated by the particular application for the filament.
In addition, after formation, the filament may be treated by any method appropriate to the desired final use. For instance, in particular regarding textiles, this may include dyeing, coloring with pigments, sizing, or the addition of chemical agents such as antistatic agents, flame retardants, UV light stabilizers, antioxidants, pigments, dyes, stain resistants, and/or antimicrobial agents. In addition, the filaments may be treated to impart additional desired characteristics such as strength, elasticity or shrinkage. While the filaments and yarns may be treated using such techniques, it should be understood that the resulting article may also be treated using such techniques. Nevertheless, examples of suitable treatments and application methods are found in “Textile coloration and finishing,” by Warren S. Perkins, Carolina Academic Press, Durham, NC, 1996.
Thus, generally, the method of making a filament or a monofilament yarn as disclosed herein may include at least the following: extruding a melt comprising the thermoplastic copolyester elastomer composition comprising the thermoplastic copolyester elastomer through a spinneret; withdrawing a filament from the spinneret; and collecting the filament on a winding roller. In addition, the method may also comprise quenching the filament using air. Such quenching may be conducted before drawing, if drawing is conducted, the filament. Also, the method may comprise applying a finish to the filament. Such application may also be conducted before drawing, if drawing is conducted, the filament; in addition, it may be done after quenching. Also, the method may include a step of drawing the filament using a draw roller. Such drawing may be conducted after quenching and/or after applying a finish.
Further, generally, the method of making a multifilament yarn as disclosed herein may include at least the following: extruding a melt comprising the thermoplastic copolyester elastomer composition comprising the thermoplastic copolyester elastomer through a spinneret; withdrawing a first filament and a second filament from the spinneret; and collecting the first filament and the second filament on a winding roller. When a third filament (or more) is present, the aforementioned steps may be the same for forming the third filament. In addition, the method may also comprise quenching the first filament and the second filament using air. Such quenching may be conducted before drawing, if drawing is conducted, the filament. If present, quenching may also be conducted on a third filament. Also, the method may comprise applying a finish to the first filament and the second filament. Such application may also be conducted before drawing, if drawing is conducted, the filament; in addition, it may be done after quenching. If present, application of the finish may also be conducted on a third filament. Also, the method may include a step of drawing the first filament and the second filament using a draw roller. Such drawing may be conducted after quenching and/or after applying a finish. The method may also include a step of drawing a third filament, if present. In addition, the method of making the multifilament yarn may also include a step of converging the filaments to form the multifilament yarn.
Further in accordance with the present disclosure, a melt spinning process is also disclosed for spinning filaments, in particular continuous filaments. In this regard, the process will be described with respect to
In general, the process comprises passing a melt comprising a thermoplastic copolyester elastomer composition, including a thermoplastic copolyester elastomer, through a spinneret to form a plurality of stretchable, synthetic elastomeric filaments. With reference to
The filaments can be treated with a finish as defined herein using any known technique at a finish applicator 5a, 5b as shown in
The filament 8, which may or may not be drawn optionally can be partly relaxed, for example, with steam at 9 in
In addition, relaxation of the filaments may be conducted by utilizing the rolls/rollers present within the process. For instance, as disclosed herein, the process may include a feed roller to which a filament may be withdrawn from the spinneret. The process may also include a draw roller or godet roller after the feed roller. Finally, the filament/yarn may be taken up by a winding roller. By controlling the speeds of the respective rollers, the filament and/or yarn may have an opportunity to relax. For instance, in one embodiment, the feed roller speed may be greater than a draw roller speed or if no drawing, a godet roller speed. In one embodiment, the draw roller speed or if no drawing, a godet roller speed may be greater than a winding roller speed. In a further embodiment, the feed roller speed may be greater than a draw roller speed or if no drawing, a godet roller speed and the draw roller speed or if no drawing, the godet roller speed may be greater than a winding roller speed.
The quenched, optionally drawn, and optionally relaxed filaments can then be collected by winding at winder 11 in
In one embodiment, the winding speed may be less than the draw (or godet) roll speed. For instance, the draw (or godet) roll speed may be 75% or more, such as 80% or more such as 85% or more, such as 88% or more, such as 90% or more, such as 92% or more, such as 94% or more, such as 95% or more, such as 96% or more, such as 97% or more, such as 97.5% or more, such as 98% or more, such as 98.5% or more, such as 99% or more to less than 100% of the winding speed. Without intending to be limited by theory, it is believed that such difference in speeds may allow for the filament(s) and yarn to have an opportunity to at least partially relax.
If multiple filaments have been spun and quenched, the filaments can be converged, optionally interlaced, and then wound up. For instance, such convergence and/or interlacing may be conducted to form multifilament yarns. Single filament or multifilament yarns may be wound up at winder 11 in
As indicated herein, the filaments may be utilized to make a yarn. A yarn may include, but is not limited to, a number of filaments twisted together (spun yarn), a number of filaments laid together without twist (a zero-twist yarn), a number of filaments laid together with a degree of twist, and a single filament with or without twist (a monofilament).
In one embodiment, a multifilament yarn as disclosed herein may have no twist. In another embodiment, the multifilament yarn as disclosed herein may have a relatively small degree of twist. For instance, the twist may be 1 or less twists per inch, such as 0.9 or less twists per inch, such as 0.8 or less twists per inch, such as 0.7 or less twists per inch, such as 0.6 or less twists per inch, such as 0.5 or less twists per inch, such as 0.4 or less twists per inch, such as 0.3 or less twists per inch, such as 0.2 or less twists per inch, such as 0.1 or less twists per inch, such as 0.05 or less twists per inch, such as 0.01 or less twists per inch. The twist may be 0 or more twists per inch, such as 0.01 or more twists per inch, such as 0.05 or more twists per inch, such as 0.1 or more twists per inch, such as 0.2 or more twists per inch, such as 0.3 or more twists per inch, such as 0.4 or more twists per inch, such as 0.5 or more twists per inch.
In addition, the multifilament yarn may have minimal entanglement. For instance, interlaced yarns may be characterized by points of entanglement, called nodes, which are separated by spaces of unentangled filaments. In this regard, the distance between the end of a first node and the beginning of a second node for a multifilament yarn as disclosed herein may be relatively long. In addition, the average distance between the nodes of a multifilament yarn may be relatively long. For instance, the distance may be about 1 or more inches, such as about 2 or more inches, such as about 3 or more inches, such as about 4 or more inches, such as about 5 or more inches, such as about 6 or more inches, such as about 8 or more inches, such as about 10 or more inches, such as about 12 or more inches, such as about 16 or more inches, such as about 20 or more inches, such as about 24 or more inches, such as about 30 or more inches, such as about 36 or more inches, such as about 42 or more inches, such as about 48 or more inches, such as about 54 or more inches, such as about 60 or more inches.
As indicated herein, the yarn may generally have any filament count. For instance, the yarn may be a monofilament yarn formed from a single filament.
Alternatively, the yarn may be a multifilament yarn formed from two or more filaments wherein such two or more filaments may be wound to form the yarn. Accordingly, the multifilament yarn comprises a first filament that is at least partially adhered to a second filament. In addition, the multifilament yarn may further comprise a third filament wherein the third filament is at least partially adhered to the first filament, the second filament, or both. In particular, the multifilament yarn may include a first filament, a second filament, and a third filament wherein such filaments are at least partially adhered to each other. In this regard, in one embodiment, such filaments may simply be adhered to one another wherein such points of adhesion between filaments may not be a fusion wherein fusion is defined as combining or connecting the filaments at a temperature over the polymer melt temperature.
In this regard, the multifilament yarn may comprise at least about 2 filaments. The multifilament yarns may comprise about 2 or more, such as about 3 or more, such as about 5 or more, such as about 10 or more, such as about 15 or more, such as about 20 or more, such as about 25 or more filaments, such as about 50 or more, such as about 100 or more filaments. The multifilament yarn may comprise about 200 or less, such as about 100 or less, such as about 80 or less, such as about 60 or less, such as about 50 or less, such as about 40 or less, such as about 35 or less, such as about 30 or less, such as about 25 or less, such as about 20 or less, such as about 15 or less, such as about 10 or less, such as about 5 or less, such as about 4 or less, such as about 3 or less filaments.
The yarns may have a total denier of from about 1 to about 2000. For instance, the total denier may be about 1 or more, such as about 5 or more, such as about 10 or more, such as about 20 or more, such as about 30 or more, such as about 40 or more, such as about 50 or more, such as about 70 or more, such as about 100 more, such as about 120 or more, such as about 140 or more, such as about 160 or more, such as about 180 or more, such as about 200 or more, such as about 300 or more, such as about 500 or more, such as about 800 or more, such as about 1000 or more, such as about 1300 or more, such as about 1500 or more, such as about 1800 or more, such as about 2000 or more. The total denier may be about 3000 or less, such as about 2800 or less, such as about 2500 or less, such as about 2200 or less, such as about 2000 or less, such as about 1800 or less, such as about 1600 or less, such as about 1400 or less, such as about 1200 or less, such as about 1000 or less, such as about 800 or less, such as about 600 or less, such as about 500 or less, such as about 450 or less, such as about 400 or less, such as about 350 or less, such as about 300 or less, such as about 275 or less, such as about 250 or less, such as about 225 or less, such as about 200 or less, such as about 180 or less, such as about 160 or less, such as about 140 or less, such as about 120 or less, such as about 100 or less, such as about 80 or less, such as about 60 or less, such as about 50 or less. The denier may be determined in accordance with D2259-02(2016) at a temperature of about 23° C.
In addition, the yarn may have a particular linear density as it relates to the filaments that make up the yarn. For instance, the yarn may have at least about 0.1 denier per filament (dpf), such as at least about 0.2 dpf, such as at least about 0.5 dpf, such as at least about 0.7 dpf, such as at least about 1 dpf, such as at least about 2 dpf, such as at least about 3 dpf, such as at least about 4 dpf, such as at least about 5 dpf, such as at least about 8 dpf, such as at least about 10 dpf, such as at least about 20 dpf, such as at least about 30 dpf, such as at least about 50 dpf, such as at least about 70 dpf, such as at least about 90 dpf, such as at least about 110 dpf, such as at least about 130 dpf, such as at least about 150 dpf, such as at least about 200 dpf, such as at least about 300 dpf, such as at least about 500 dpf, such as at least about 800 dpf, such as at least about 1,000 dpf, such as at least about 1,200 dpf, such as at least about 1,400 dpf, such as at least about 1,600 dpf. The yarn may have about 2,000 dpf or less, such as about 1,700 dpf or less, such as about 1,500 dpf or less, such as about 1,300 dpf or less, such as about 1,100 dpf or less, such as about 900 dpf or less, such as about 700 dpf or less, such as about 500 dpf or less, such as about 450 dpf or less, such as about 400 dpf or less, such as about 350 dpf or less, such as about 300 dpf or less, such as about 250 dpf or less, such as about 200 dpf or less, such as about 180 dpf or less, such as about 150 dpf or less, such as 130 pdf or less, such as 110 dpf or less, such as 100 dpf or less, such as 90 dpf or less, such as 80 dpf or less, such as 70 dpf or less, such as 60 dpf or less, such as 50 or less dpf, such as about 40 or less dpf, such as about 35 or less dpf, such as about 30 or less dpf, such as about 25 or less dpf, such as about 22 or less dpf, such as about 20 or less dpf, such as about 18 or less dpf, such as about 16 or less dpf, such as about 14 or less dpf, such as about 12 or less dpf, such as about 10 or less dpf, such as about 8 or less dpf, such as about 6 or less dpf, such as about 5 or less dpf, such as about 4 or less dpf, such as about 3.5 or less dpf, such as about 3 or less dpf, such as about 2.5 or less dpf. Without intending to be limited, the dpf may be relatively lower for certain applications than other applications. For instance, the dpf may be relatively lower for textile applications than for industrial applications. Regardless, the size and strength of such a filament can be readily determined using means generally known in the art.
As indicated herein, the filaments may have a particular cross-section as dictated by the spinneret design. Generally, the filament may have an axial core extending along the continuous length direction of the filament. In this regard, the axial core may comprise the thermoplastic copolyester elastomer as defined herein in one embodiment. In another embodiment, the axial core of the filament may be hollow, such that it does not include the thermoplastic copolyester elastomer or composition as defined herein.
In one embodiment, the filament may generally have a circular cross-section. In another embodiment, the filament may generally have a non-circular cross-section. For instance, the filament may generally have an oval-shaped cross section. However, it should be understood that other non-circular cross-sections may also be formed from the thermoplastic copolyester elastomer as disclosed herein.
In another embodiment, the filament may be multilobal. For instance, the filament may include two or more lobes. Such lobes may be radially disposed from the axial core. In this regard, the lobes may extend from a central portion or axial core of a filament wherein each lobe has a proximal end adjacent the central portion and a distal end radially spaced apart from the proximal end. Furthermore, each lobe may have a convex curve. In this regard, each lobe may be free of a relatively flat surface.
Furthermore, each lobe may be directly connected to one another in one embodiment. In this regard, such connection point between adjacent lobes may be referred to as a cusp. Alternatively, adjacent lobes may not be directly connected. Such an area connecting two adjacent lobes may be referred to as a lobe connection. Such lobe connections may also have a relatively convex curve. Similar to the lobes, such lobe connections may also be free of a relatively flat surface.
In addition, the lobes may be positioned symmetrically about the filament. In other words, the filament may have a symmetrical cross-section in one embodiment. In another embodiment, the filament may have an asymmetrical cross-section. Also, the lobes may be asymmetrical or symmetrical. In one embodiment, the lobes may be asymmetrical. In another embodiment, the lobes may be symmetrical.
In one embodiment, the filament may have a core/sheath configuration. For instance, the axial core may be formed of a thermoplastic copolyester elastomer composition as defined herein. Such composition may be referred to as a first thermoplastic copolyester elastomer composition. In addition, the sheath may be formed from a second thermoplastic copolyester elastomer composition. Such second thermoplastic copolyester elastomer composition may be different from the first thermoplastic copolyester elastomer composition in at least one aspect. For instance, even though both may contain a thermoplastic copolyester elastomer as defined herein, a respective property of each thermoplastic copolyester elastomer may be different. In this regard, the first thermoplastic copolyester elastomer composition may comprise a first thermoplastic copolyester elastomer and the second thermoplastic copolyester elastomer composition may comprise a second thermoplastic copolyester elastomer wherein the first thermoplastic copolyester elastomer is different from the second thermoplastic copolyester elastomer in at least one aspect.
Furthermore, as indicated herein, the filament yarn may include two or more lobes radially disposed about the axial core. In this regard, the lobes may be formed from the second thermoplastic copolyester elastomer composition and second thermoplastic copolyester elastomer. For instance, the axial core may be formed from the first thermoplastic copolyester elastomer composition and the first thermoplastic copolyester elastomer and the sheath, including the lobes, may be formed from the second thermoplastic copolyester elastomer composition and the second thermoplastic copolyester elastomer.
Examples of various cross-sections of monofilaments are illustrated in
Referring to
Referring to
Referring to
Examples of various multifilament yarns are illustrated in
As illustrated in
The present inventors have discovered that the advantageous properties of the filaments and yarns as disclosed herein can allow for them to be utilized to form various articles for various applications. In this regard, the filaments may be utilized to form yarns which may be used to prepare woven, knit, and/or nonwoven articles which can be prepared using conventional techniques including, but not limited to, meltblown, spunbonded, card and bond, including heat bonding (hot air and point bonding), air entanglement, and other techniques. For instance, they may be subjected to various high-speed conditions for the formation of such articles.
In addition, the configuration of the yarn may depend on the particular application. For instance, the yarn may be utilized as a bare yarn or a covered yarn. In one embodiment, the yarns may be utilized themselves as bare yarns. Alternatively, the yarns may be used as covered yarns wherein the yarn as described herein may be utilized as the core. For such covered yarn, an inelastic filament or yarn or a short fiber yarn may wrap the core, in particular in a spiral manner. In addition or alternatively, another elastic yarn may also be utilized to cover.
As examples, the yarns can be utilized for textile fabrics for apparel and home furnishings. For example, the yarns may be stretchable and exhibit a desired recovery which may be desired for such applications. In this regard, the yarns may be utilized for textiles. In particular, the yarns may be utilized make fabrics, such as knit fabrics or woven fabrics. As a result, the yarns may be considered knittable yarns, in particular knittable, stretchable yarns.
The knit construction of the yarns is not necessarily limited by the present disclosure. For instance, various types of knit constructions as known in the art may be utilized to form a fabric and/or resulting article utilizing the filaments and yarns as disclosed herein. As just certain examples, the knit construction may be one as disclosed in U.S. Pat. Nos. 9,689,092, 10,370,782, or US Patent Publication No. 2021/0254244, all of which are hereby incorporated in their entirety.
In one particular embodiment, the knit construction may be a circular knit construction. Without intending to be limited, articles formed from circular knit constructed fabrics may be more comfortable than other knit constructions partially due to the ability of the fabric to stretch. For instance, when a force is applied, the circular knit fabric may stretch slightly due to the compression and/or elongation that may occur among the stitches/loops of the fabric and then may recover.
Generally, knitting is a process for constructing a fabric by interlocking a series of loops (bights) of one or more strands organized in wales and courses. In general, knitting includes warp knitting and weft knitting. In warp knitting, a plurality of strands runs lengthwise in the fabric to make all the loops. In weft knitting, one continuous strand runs crosswise in the fabric, making all the loops in one course. Weft knitting includes fabrics formed on both circular knitting and flat knitting machines. With circular knitting machines, the fabric is produced in the form of a tube, with the strands running continuously around the fabric. With a flat knitting machine, the fabric is produced in flat form, the threads alternating back and forth across the fabric. The resulting textile includes an interior side (the technical back) and an exterior side (the technical face), each layer being formed of the same or varying strands and/or stitches. By way of example, the knit structure may be a single knit/jersey fabric, a double knit/jersey fabric, and/or a plated fabric (with yarns of different properties are disposed on the face and back).
The textile may be formed via weft knitting, where one continuous thread runs crosswise in the fabric making all of the loops in one course. Preferably, the weft knitted textile is formed via circular knitting, in which the textile is produced in the form of a tube, with the threads running continuously around the textile.
Referring to
However, while that may be the case, it should be understood that other types of strands and yarns may also be utilized. For instance, in the knit structure 500, in one embodiment, at least one strand 515 may be another strand typically used in the art and not a thermoplastic copolyester elastomer-based yarn as disclosed herein. For instance, in one embodiment, such strand may be another type of elastic strand. These may include strands of anidex, elastoester, bi-constituent filament rubber, and combinations thereof. By way of specific example, elastane, a manufactured fiber in which the fiber-forming substance is a long chain synthetic polymer composed of at least 85% of segmented polyurethane, may be utilized. Alternatively, in one embodiment, such strand may be an inelastic strand, typically not formed of an elastomeric material. These strands may include natural fibers including cellulosic fibers (e.g., cotton, bamboo) and protein fibers (e.g., wool, silk, and soybean) as well as synthetic fibers including polyester fibers (poly(ethylene terephthalate) fibers and poly(trimethylene terephthalate) fibers), polycaprolactam fibers, poly(hexamethylene adipamide) fibers, acrylic fibers, acetate fibers, rayon fibers, nylon fibers and combinations thereof.
In this regard, when other strands are utilized in the knit structure, the strand 505 formed from the thermoplastic copolyester elastomer-based yarn as disclosed herein may form approximately every second course 505 to approximately every eleventh course 505 (e.g., the strand is placed every 4th-10th course). Preferably, such strand may form every fourth, fifth, or sixth course 505 within the knit structure 500. Typically, the spacing may remain consistent throughout the knit structure 500. In other embodiments, the spacing of such strand 505 may be varied to alter the recovery and/or stretch properties throughout the article (e.g., garment). By way of specific example, such strand 515 may form every fourth course 505 of an article for one portion of the article but form every sixth course along another portion of the article.
In a further embodiment, each strand 515 may include a strand formed from the thermoplastic copolyester elastomer as disclosed herein paired with a corresponding strand 515 (e.g., the strands are braided or otherwise commingled). The strand pair is then utilized to form courses 505 within the knit structure 500.
With either configuration, the amount of the strand 515 formed from the thermoplastic copolyester elastomer as disclosed herein may be present in the knit structure in an amount by weight of about 0.1% or more, such as about 0.5% or more, such as about 1% or more, such as about 2% or more, such as about 3% or more, such as about 5% or more, such as about 10% or more, such as about 15% or more, such as about 20% or more, such as about 25% or more, such as about 30% or more, such as about 40% or more, such as about 50% or more, such as about 60% or more, such as about 70% or more, such as about 80% or more, such as about 90% or more, such as about 95% or more, such as about 100%. Such strand may be present in an amount by weight of about 100% or less, such as about 98% or less, such as about 95% or less, such as about 90% or less, such as about 80% or less, such as about 75% or less, such as about 70% or less, such as about 65% or less, such as about 60% or less, such as about 55% or less, such as about 50% or less, such as about 45% or less, such as about 40% or less, such as about 35% or less, such as about 30% or less, such as about 25% or less, such as about 20% or less, such as about 15% or less, such as about 10% or less, such as about 5% or less.
The knit structure may also be a double-knit structure. Generally, such a structure can be formed on a knit machine having two needle beds. These machines may include, but are not limited to, a V-bed flat knit machine, a double jersey circular knit machine, and the like. The double-knit structure may provide a technical face that is knit on one of the needle beds, and a technical back that is knit on the remaining needle bed of the knit machine. When looking at the technical face and the technical back of the double-knit structure, both sides may look like the technical face of a single-knit jersey and contain face loops or weft knit loops. In certain embodiments, linking yarns may be used to connect the technical face and the technical back of the double-knit structure where the linking yarns pass back and forth between the two different needle beds. The double-knit structure may be formed on a machine where the needles in one bed are directly opposite the needles in the other bed (known as interlock gaiting). The double-knit structure may also be formed on a machine where the needles in one bed are directly opposite spaces in the other bed (known as rib gaiting).
In the above double-knit structure, the technical face may form an outer-facing surface of a resulting article and the technical back may form an inner-facing surface of a resulting article. The technical face of the structure may be formed from a first yarn. The first yarn may be any type of yarn generally utilized in the yarn, such as a non-elastic yarn or an elastic yarn, for example a yarn as disclosed herein. The non-elastic yarn may include polyamide yarns, cotton yarns, and/or polyester yarns. The technical back of the structure may be formed from a second yarn and optionally the first yarn. The second yarn may be an elastic yarn, such as a yarn disclosed herein.
With such a configuration, the amount of the second elastic yarn may be present in the knit structure in an amount by weight of about 0.1% or more, such as about 0.5% or more, such as about 1% or more, such as about 2% or more, such as about 3% or more, such as about 5% or more, such as about 10% or more, such as about 15% or more, such as about 20% or more, such as about 25% or more, such as about 30% or more, such as about 40% or more, such as about 50% or more, such as about 60% or more, such as about 70% or more, such as about 80% or more, such as about 90% or more, such as about 95% or more, such as about 100%. Such yarn may be present in an amount by weight of about 100% or less, such as about 98% or less, such as about 95% or less, such as about 90% or less, such as about 80% or less, such as about 75% or less, such as about 70% or less, such as about 65% or less, such as about 60% or less, such as about 55% or less, such as about 50% or less, such as about 45% or less, such as about 40% or less, such as about 35% or less, such as about 30% or less, such as about 25% or less, such as about 20% or less, such as about 15% or less, such as about 10% or less, such as about 5% or less.
The knit structure, regardless of whether in accordance with the structure of
In this regard, the apparel or garment may include, but is not limited to, short or long-sleeved shirts, tank tops, undershirts, jackets, coats, pants, trousers, shorts, socks, undergarments, nylons/leggings, dresses, skirts, hats/headgear, outerwear, etc. Other articles of apparel or garments include, but are not limited to, sleepwear, swimwear, compression garments, denim, stretchable clothing, including athletic wear, etc. Other uses, aside from garments, for these fabrics include but are not limited to, upholstery, curtains, toys, fitted covers for automobiles, furniture, equipment, etc.
Elongation at Break and Tenacity: The elongation at break and tenacity were determined in accordance with ASTM D2653-07(2018) at a temperature of about 23° C. Regarding the apparatus for conducting the test, Option A under the clamping assembly was utilized. The tensile testing machine was utilized with a gage length of about 2 inches. For this test, ten specimens were tested, and the average was recorded.
Denier and Fiber Shrinkage: The denier and fiber shrinkage were determined in accordance with ASTM D2259-02(2016). The denier was determined at a temperature of about 23° C. For these tests, 90 wraps were completed while carefully tying the loose ends without inducing extra tension into the skein and cutting any excess yarn. For determining the denier, a skein was placed on a balance to record the weight and obtain a denier value based on the skein length in accordance with the standard method. In addition, the fiber shrinkage was determined in accordance with Section 6.6.1, Step 13 using dry heat exposure at a temperature of about 120° C. In particular, the skein was hung on the inside of the oven and allowed to heat relax in the oven for 15 minutes. Thereafter, the length of the skein was measured to determine the amount of shrinkage.
A thermoplastic copolyetherester elastomer (flexural modulus—45 MPa; hardness—33 Shore D; Tm—193° C.; density—1.1 g/cm3) was spun to form a trilobal monofilament yarn in accordance with the general schematic illustrated in
The spinning process yielded a 40-denier trilobal monofilament yarn. In addition, the yarn also exhibited the following: tenacity—1.07 g/d; elongation at break—425%, shrinkage—6.2%.
A thermoplastic copolyetherester elastomer (flexural modulus—45 MPa; hardness—33 Shore D; Tm—193° C.; density—1.1 g/cm3) was spun to form a multifilament yarn formed from three filaments in accordance with the general schematic illustrated in
The spinning process yielded a 40-denier multifilament yarn. In addition, the yarn also exhibited the following: tenacity—1.04 g/d; elongation at break—393%, shrinkage—7.9%.
These and other modifications and variations of the present disclosure may be practiced by those of ordinary skill in the art, without departing from the spirit and scope of the present disclosure. In addition, it should be understood that aspects of the various embodiments may be interchanged both in whole or in part. Furthermore, those of ordinary skill in the art will appreciate that the foregoing description is by way of example only and is not intended to limit the invention so further described in such appended claims.
The present application claims filing benefit of U.S. Provisional Patent Application No. 63/498,866 having a filing date of Apr. 28, 2023, which is hereby incorporated by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 63498866 | Apr 2023 | US |
