JPH0154444B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a polyester-based heat-adhesive fiber, and its purpose is to have excellent heat-adhesive properties, and to enable smooth production of fibers and fiber aggregates using the fibers without any process troubles. The purpose of this invention is to provide fibers that can be manufactured in the following manner. Thermoadhesive fibers for producing nonwoven fabrics and the like by interfiber thermal fusion are known. For example, there are composite fibers with polypropylene and polyethylene as an adhesive component, or composite fibers with polyethylene terephthalate and polyethylene-vinyl alcohol copolymer as an adhesive component. In recent years, polyester fibers such as polyethylene terephthalate (hereinafter abbreviated as PET) have become increasingly important in the textile field, especially in the nonwoven fabric field. In particular, there is a growing demand for manufacturing nonwoven fabrics, and adhesive fibers for polyester are strongly desired. The above-mentioned known adhesive fibers have good thermal adhesion properties between adhesive polymers, but when used in combination with other main fibers for nonwoven fabrics, etc., the types of main fibers that can be bonded are very limited. However, no material that can be adhered to polyester has been obtained. For example, although polyethylene is self-adhesive, it hardly adheres to common commercially available fibers that have different chemical structures. Furthermore, copolymerized nylon adheres to nylon fibers, but does not adhere to polyester fibers, which are also condensed polymers. In addition, ethylene
Vinyl alcohol copolymers exhibit adhesion to rayon, vinylon, or nylon, which have relatively similar solubility parameters, but they also do not adhere to polyester. In order to bond polyester fibers, it is common sense to use a polyester polymer as an adhesive component due to the similarity in chemical structure and solubility parameters. In fact, solvent-soluble or hot adhesive adhesives are used to bond polyester.
Many copolymerized polyesters have been proposed as melt-type adhesives. However, when copolymerized polyester is used as an adhesive fiber, it passes through specific equipment and a specific heat history in the fiber or nonwoven fabric manufacturing process.
Ordinary copolyesters for adhesives cannot be used at all. For example, when extruding a molten polymer through a spinneret to form fibers and storing the fiber bundle in a can or winding it onto a bobbin, there is severe adhesion between single fibers or fiber bundles, making it difficult to obtain spun fibers. . If the fibers are subsequently stretched, crimped, cut, etc., further adhesion and fusion occur, making it impossible to obtain good fibers. In particular, when handling fiber bundles with a large total denier in order to increase the production volume, problems in the fiber manufacturing process become even more pronounced. Furthermore, even if fiberization is performed incompletely, for example, when it is made into a non-woven fabric, the card passability is poor or adhesion problems occur repeatedly during the adhesion process, making it impossible to make the fabric into a non-woven fabric. The process properties required for this spinning and subsequent fiberization and nonwoven fabric manufacturing processes are extremely strict, and the molten polymer is removed from the polymerization tank.
Even if the pellets go through the chipping process of cutting them into pellets and the drying process before feeding the pellets to an extruder directly connected to a spinning machine without any trouble, there are very few products that can be made into fibers or non-woven fabrics. On the other hand, depending on the type of copolymerized polyester, if the amount of copolymerization is reduced and the degree of modification is lowered, the processability of producing fibers or nonwoven fabrics can be improved.
PET or polybutylene terephthalate (hereinafter abbreviated as PBT), which is currently mass-produced commercially.
Generally, it has low adhesiveness with polyesters such as polyesters, and cannot be used as adhesive fibers. The present inventors have conducted various studies on fibers that have excellent adhesion to polyester and are easy to process in the production of fibers and nonwoven fabrics, etc. As a result, the inventors have found that a specific type of fiber for use in fibers, which is completely different from that for adhesives, has been found. It has been found that a copolyester having a copolymer composition and specific physical properties is suitable. That is, the copolymerization ratio of terephthalic acid (TA) to the total acid component is 50 mol% or more, 1,
The total amount of 4-butanediol (hereinafter abbreviated as BD) and 1,6-hexanediol (hereinafter abbreviated as HD) is 70 mol% or more, and the third component described below is 5 to 45% by mole.
Contains mol%, melting point is 80-200℃, heat of crystal fusion (ΔHu) is 2.0ca/g or more, minimum crystallization time (hereinafter referred to as CTmin).
It was discovered that a copolyester with a shear strength (SS) of 5 kg/cm ² or more when bonded to PET with a bonding time of less than 90 seconds (abbreviated as ) has the potential to achieve both adhesion and processability. . However, for industrial production purposes, there are very strict requirements regarding the manufacturing process of fibers, etc.
Advanced level is desired. In other words, even if process passability or quality reaches a certain level in short-time, small-scale trial production, trial production with various manual adjustments, or trial production under special conditions, it is insufficient, and long-term production is insufficient. Stability of production over a wide range over a period of time is required. In this sense, the above-mentioned copolyesters are still insufficient and require further improvement. Therefore, as a result of further investigation into improving the stability of the process and quality, the present inventors discovered that the above-mentioned copolymerized polyester, copolymerized with α-olefin and mono- or divalent metal salt of unsaturated carboxylic acid, etc. It has been discovered that the above-mentioned problems can be completely solved for the first time by using fibers made of a copolymerized polyester composition, and adhesive fibers with good adhesion and extremely excellent process stability can be obtained. It is known to add the copolymers of the invention to reinforced PET to improve the surface appearance of molded articles. It is also known to add it to a polyester resin composition for metal coating to improve the adhesion to metal and the moldability of coated metal plates. However, it is completely unknown that fibers with good adhesion and processability can be obtained from a composition made of the specific copolyester defined in the present invention and the copolymer of the present invention. In order to make thin wires into fibers, extremely strict processing is required compared to ordinary resin molding, and consideration from a different perspective is required. It was discovered that fibers can be obtained. The copolymerized polyester of the present invention has a copolymerization composition (hereinafter referred to as The copolymer composition is expressed as mol% of the total acid composition), and TA is
The content used is 50 mol% or more, preferably 60 mol% or more, more preferably 70 mol% or more.
If the TA content is less than 50 mol%, the fiber quality and processability are not good, and the cost is also not appropriate. Further, the copolymerized polyester of the present invention has a total content of BD and HD of 70 mol% or more, preferably 75 mol% or more, and more preferably 80 mol% or more. If the total amount is less than 70 mol%, the physical properties are unfavorable, the quality of the fiber and the processability are reduced, and the cost is also not appropriate. Furthermore, the copolymerized polyester of the present invention has a tertiary
The amount of the component used is 5 to 45 mol%, preferably 6 to 37 mol%. The higher the mole number, the better the adhesion and texture of the nonwoven fabric, but the greater the mole number than 45 mole %, which is undesirable because processability deteriorates. Here, the third component is one that lowers the melting point or hardness, but preferably causes as little decrease in crystallinity as possible, such as adipic acid, sebacic acid, hydroxyacetic acid, trimethylene glycol, pentamethylene glycol, diethylene glycol, and triethylene glycol. , polyethylene glycol, cyclohexanedimethanol, propylene glycol, neopentyl glycol, ethylene glycol, and isophthalic acid. The copolymerized polyester used in the fibers of the present invention must satisfy all of the above compositional conditions, but also ensure the stability of the fiber and nonwoven fabric manufacturing process at the commercial production level and the quality as adhesive fibers and nonwoven fabrics. In order to do so, the following physical properties must also be appropriate. That is, the copolymerized polyester of the present invention has a melting point of 80 to 200°C, preferably 90 to 185°C, and more preferably 100 to 175°C. If the temperature is lower than 80°C, the heat resistance of the fiber or nonwoven fabric is insufficient, resulting in poor practical performance. On the other hand, if the temperature is higher than 200°C, high temperatures are required for bonding, making it impossible to use conventional equipment, or even if high-temperature processing equipment is used, the molded product may become deformed, its texture may deteriorate, and energy loss may occur. I don't like it because there are a lot of them. Further, the copolymerized polyester of the present invention has a heat of crystal fusion (ΔHu) of 2.0 ca/g or more, preferably
2.5ca/g or more, more preferably 3.0ca/g
The above are used. If it is less than 2.0ca/g, it is undesirable because it tends to cause sticking during fiber production.
To measure ΔHu, a sample is taken out from the molten polymer as fine fibers or thin film pieces, cooled, and left at room temperature for three days or more. The sample is then subjected to a differential scanning calorimeter (DSC) at a rate of 10°C/min in nitrogen. It is determined from the area of the endothermic peak during melting. Furthermore, the copolymerized polyester of the present invention has a minimum crystallization time (CTmin.) of 90 seconds or less, preferably
A time period of 70 seconds or less, more preferably 50 seconds or less is used. If the time is longer than 90 seconds, sticking may occur during fiber production, which is undesirable. CTmin. is defined as the crystallization start time, which is defined as the time at which substantially non-oriented film particles placed in a silicon bath or water bath at a predetermined temperature from the molten state are left in the bath, and whitening starts. The crystallization initiation time in the temperature range of 120°C is the shortest crystallization initiation time. To determine CTmin., it may be left in the air without being placed in a bath, but it is preferable to do so in a bath because the heat exchange rate is higher and the influence of the cooling process can be reduced. Adopt the value inside. To find CTmin., change the temperature and
It is not necessarily necessary to measure CTmin. itself; it is a sufficient condition that the crystallization time is within 90 seconds at a certain temperature in the range of 0 to 120°C.
The temperature indicating CTmin. may be close to 0°C, or may be near 120°C. The crystallization time in the actual fiber manufacturing process varies depending on temperature history, etc.
It goes without saying that the crystallization rate in the process will be faster if the temperature is set to indicate CTmin. In addition, when fibers are highly oriented, such as during spinning, the crystallization rate may increase, but as defined in the present invention,
CTmin. can be used as a measure related to process performance. In addition, the copolymerized polyester of the present invention is PET
Shear strength of film bonded (hereinafter abbreviated as SS)
A material with a weight of 5 kg/cm ² or more, preferably 6 kg/cm ² or more, more preferably 7 kg/cm ² or more is used.
If it is less than 5 kg/cm ^{2 ,} the adhesive strength in fibrous form, especially the strength of nonwoven fabrics, will be insufficient, which is not preferable. What is the SS of the present invention? A copolyester film with a thickness of 0.3 mm and a biaxially stretched PET film made by Mitsubishi Plastics (trade name, Diafoil, thickness 0.1 mm) are heated to a temperature 20°C higher than the melting point of the copolyester. After heating and melting and bonding at a pressure of 5Kg/ ^cm2 , the temperature is 20℃.
The value was measured at a tensile speed of 20 cm/min after being left in a room at 65% relative humidity and 65% temperature for 24 hours. The copolyester of the present invention or its composition may contain small amounts of additives, such as matting agents such as titanium oxide, antioxidants, fluorescent brighteners, stabilizers, or ultraviolet absorbers. You can stay there. The copolymer of α-olefin and a mono- or divalent metal salt of an unsaturated carboxylic acid to be blended into the copolymer of the present invention is called an “ionomer”. There are many types of carboxylic acid metal salt compounds or polymers containing carboxylic acid metal salts, but they may form foreign substances in the composition, causing yarn breakage during spinning or drawing for fiberization, or causing problems in the composition. In many cases, the ionomer of the present invention causes coloring, has insufficient effect of improving processability, or decreases adhesion.It is therefore difficult to obtain fibers with good quality such as adhesion and processability using the ionomer of the present invention. can. Specific examples of ionomers include copolymers of ethylene and acrylic acid, methacrylic acid, maleic acid, or itaconic acid in which some or all of the carboxyl groups are sodium, potassium, lithium,
Some are salts of mono- or divalent metals such as zinc, magnesium, and calcium. The copolymerization rate of unsaturated carboxylic acid monomer in the ionomer is 0.7~
It is 25 mol%, preferably 1.0 to 20 mol%. The degree of neutralization of carboxyl groups is 10-100%, preferably
It is 15-80%. Examples of commercially available ionomers include Dupont's "Surlyn," Mitsui Polychemicals'"Himilan," and Asahi Dow's "Copolene."
and so on. The amount of ionomer blended in the composition is 0.5 to 20%, preferably 1% by weight based on the total weight of the composition.
~15%, more preferably 2-10% is used. If it is less than 0.5%, the blending effect will be insufficient, and if it is more than 20%, the adhesion will decrease, and furthermore, the processability may deteriorate, which is not preferable. In order to blend the ionomer of the present invention, it may be added to the polymerization equipment during or after the polymerization of the copolyester, but depending on the polymerization conditions or blending conditions, non-mixable foreign substances may be generated. , or may cause discoloration. Therefore, it is preferable to mix and blend them in pellet form or molten state before spinning. The physical properties of the copolyester when an ionomer is blended before the completion of the polymerization reaction mean the physical properties of the copolyester alone, which are close to [η] corrected for the amount of ionomer in the composition after the completion of polymerization. It is preferable that the fibers made of the composition of the present invention and the fiber aggregates and nonwoven fabrics made from the fibers be manufactured using unique machinery and equipment most suitable for the production. It can be manufactured without modification. Further, the present invention has great significance in that the fibers are specified so that conventional machines and devices can be used. The fiber of the present invention can be used as a single fiber (homofilament) by spinning the composition alone, but it can also be used as a composite fiber by spinning it together with other melt-spun polymers. As other composite spinning components, thermoplastic polymers having a melting point of 150° C. or higher are used. Examples include PET, PBT, nylon-6, nylon-6,
6. Polypropylene, etc. When used as an adhesive fiber, the ratio of the composition component containing the copolymerized polyester to the total circumference of the composite fiber cross section, that is, the fiber cross-sectional circumference is preferably 40% or more. Although the fibers of the present invention can be used as modified fibers other than adhesive fibers, they are very suitable for use as adhesive fibers that are subjected to fusing treatment at temperatures above the softening point of the fibers. The fibers of the present invention can be used as single fibers made of the copolymerized polyester composition or as fusion-treated fiber aggregates consisting only of composite fibers of the copolymerized polyester composition and other polymers. It is also used as a mixed and fused fiber aggregate with fibers. As a fiber aggregate, it is particularly suitable for nonwoven fabrics, and it is possible to obtain nonwoven fabrics with high strength. Among these, in the case of a polyester containing TA as a component such as PET or PBT as a mixed fiber, the adhesion not only between adhesive fibers but also with the TA-based polyester is good, and a nonwoven fabric with high strength can be obtained. The present invention is of great significance in that it has made it possible to produce a good polyester nonwoven fabric, since conventionally there were no fibers that adhered to TA polyester. Next, the present invention will be explained by examples. In the examples, the mole indicating the copolymer composition amount indicates the mol% based on the total acid component of the polyester produced. In addition, [η] means that polyester is dissolved in a mixed solvent of equal weights of phenol and tetrachloroethane at 30%
Intrinsic viscosity (dl/g) measured at °C. The melting point (mp) of polyester is determined by measuring the point at which the polarized light of the sample on the hot plate disappears or the pouring point using a micro-melting point measuring device. In addition, the strength of the nonwoven fabric is 20 parts by weight of adhesive fiber.
Mixed with 80 parts by weight of PET fiber (3d x 51mm), carded, web formed and then pressed to form a 10%
The tearing length (Km) of the nonwoven fabric obtained by melting the adhesive fibers and thermally bonding them at Kg/cm ² for 1 minute is shown. Example 1 Consisting of 60 moles of TA, 100 moles of BD, and 40 moles of sebacic acid, [η] 1.10, mp153-156℃, ΔHu3.5ca
/g, crystallization time at room temperature 3 seconds, SS14.0Kg/cm ²
Add pellets of Surlyn 1555 (ionomer manufactured by DuPont, a copolymer of ethylene and about 2 mol% methacrylic acid, about two-thirds of the carboxyl groups are neutralized with sodium) to pellets of copolymerized polyester, which is The total amount of copolyester and ionomer is 5% by weight (hereinafter, the blending amount is expressed as weight% of the total composition), and the mixture is fed to an extruder and 100 spinning holes with a pore diameter of 0.4 mm are formed. Extruded from a spinneret with a spinning head temperature of 240℃, 800m/
The yarn was wound and spun in minutes. The wound fibers had almost no sticking between single fibers or fiber bundles, and could be stably spun for a long period of time. This spun yarn was stretched 3.4 times at 80°C in a water bath, then shrunk by 15% at 90°C in a water bath, and
After crimping with a studfing box type crimping machine, it is cut to have a fineness of 3.3 dr (denier) and a strength of 3.5.
It was possible to obtain fibers with g/d and elongation of 52% without any particular trouble. 20 parts by weight of this copolymerized polyester fiber and PET
80 parts by weight of fiber was blended to obtain a highly tenacious nonwoven fabric with a breaking length of 4.9 km. In addition, during the non-woven process,
No particular trouble was observed. Example 2 Copolyester of Example 1 and Surlyn 1555
Core-sheath composite spinning was carried out using a composition of 0.6 and 0.67 as a core and a core/sheath ratio of 40/60 using PET as a core. It was extruded at a spinning head temperature of 290°C and wound at 800 m/min. The wound fibers had almost no sticking between single fibers or fiber bundles, and could be stably spun for a long period of time. This spun yarn was stretched 3.7 times at 80°C in a water bath,
Subsequently, it was shrunk by 15% at 90℃ in a water bath, further crimped using a stuffing box type crimper, and then cut to give a fineness of 3.2 dr, strength of 3.8 g/d, and elongation of 51.
% of fiber could be obtained without any particular trouble. This composite fiber and PET fiber are blended, and the tear length is 4.4.
Km high strength nonwoven fabric was obtained. Incidentally, no particular trouble was observed during the non-woven process. Comparative Example 1 Using only the copolymerized polyester of Example 1 without adding any ionomer, the spinning head temperature was 240°C.
Although spinning was carried out at 800 m/min, there was significant adhesion between single fibers and between fiber bundles, and it was not possible to obtain good fibers. Furthermore, at a spinning head temperature of 200° C., the polymer discharge became unstable and a considerable amount of sticking was observed. Comparative Example 2 The copolymerized polyester of Comparative Example 1 was used as a sheath, [η]
Using 0.67 PET as a core, core/sheath composite spinning was performed at a core/sheath weight ratio of 40/60. Spinning head temperature 275
Although spinning was carried out at 800 m/min by changing the temperature from .degree. Example 3 60 mol of TA, 100 mol of BD, 20 mol of sebacic acid,
A composition containing 20 moles of isophthalic acid and a copolymerized polyester having the properties shown in Table 1 and 5% by weight of Surlyn 1555 was used as a sheath, and a composition with [η] of 0.67 was used.
Using PET as a core, core-sheath composite spinning was performed in the same manner as in Example 2, followed by stretching, shrinking, crimping, and cutting, and it was possible to obtain good fibers without any particular trouble. A high-strength nonwoven fabric with a breaking length of 4.0 km was successfully obtained from this composite fiber and PET fiber. Comparative Example 3 Core-sheath composite spinning was carried out in the same manner as in Comparative Example 2, using only the copolymerized polyester of Example 3 as a sheath and PET as a core without blending an ionomer. There was quite a lot of adhesion between single fibers, and some adhesion was also observed between fiber bundles. Example 4 (Reference example) Surlyn was added to the copolymerized polyester listed in Table 1.
A composition containing 3% by weight of 1707 (a copolymer of ethylene and about 5 mol% of methacrylic acid, approximately two-thirds of the carboxyl groups are neutralized with sodium) is used as a sheath, and a nylon-6 core is used as a core. Core-sheath composite spinning was performed at a weight ratio of /sheath = 40/60. Spinning head temperature
Extrusion was carried out at 270°C, spinning was carried out at 800 m/min, and then stretching, shrinkage, crimping and cutting were carried out to obtain good fibers without any particular trouble. A high-strength nonwoven fabric with a tearing length of 4.6 km was successfully obtained from this composite fiber and PET fiber. Comparative Example 4 Core-sheath composite spinning was performed in the same manner as in Example 4 except that no ionomer was blended. There was quite a lot of adhesion between the single fibers, and there was also some adhesion between the fiber bundles. Example 5 Surlyn was added to the copolymerized polyester listed in Table 1.
Core-sheath composite spinning was performed using a composition containing 7% by weight of 1554 (copolymer of ethylene and methallylic acid, zinc neutralized) as a sheath and a polypropylene core at a core/sheath ratio of 40/60 by weight. . Extrusion was carried out at a spinning head temperature of 285°C, spinning was carried out at 800 m/min, and then stretching, shrinkage, crimping and cutting were carried out, and good quality fibers could be obtained without any particular trouble. A high-strength nonwoven fabric with a tearing length of 3.2 km was successfully obtained from this composite fiber and PET fiber. Comparative Example 5 Core-sheath composite spinning was carried out in the same manner as in Example 5 except that the ionomer was not blended. Slight adhesion was observed between the single fibers, and there were also sticking points partially between the fiber bundles. Example 6, Example 7 (Reference Example) Core-sheath composite spinning, fiberization, and nonwoven fabrication were carried out in the same manner as in Example 2 using the compositions listed in Table 1 as sheaths, and all were performed successfully without any particular trouble. obtained fibers and nonwoven fabrics. Comparative Examples 6 and 7 Core-sheath composite spinning was carried out in the same manner as in Example 6 or Example 7, respectively, except that the ionomer was not blended. In all cases, some adhesion was observed between the single fibers, and there were also sticking points partially between the fiber bundles. Comparative Example 8 5% by weight of sodium stearate was added to the copolyester polyester pellets listed in Table 1, and the mixture was melted and pelletized. The pellets made of this composition were melted again to form a sheath component, and core-sheath composite spinning was performed in the same manner as in Example 2. During spinning, the yarn often broke, making it impossible to continue spinning smoothly. In addition, at the stage when the polymerization of the copolymerized polyester described in Table 1 was almost completed, 5% by weight of sodium stearate was added to the polymerization vessel, and after stirring and mixing under nitrogen and then under reduced pressure, extrusion was performed to form pellets. It became. The pellets made of this composition were melted again to form a sheath component, and core-sheath composite spinning was performed in the same manner as in Example 2. During spinning, the yarn often broke, making it impossible to continue spinning smoothly. Comparative Examples 9, 10, 11 and 12 Core-sheath composite spinning was carried out in the same manner as in Example 2 using the compositions listed in Table 1 as sheaths. In all cases, considerable adhesion between fibers and fiber bundles was observed, making it impossible to obtain good fibers. Comparative Example 13 Using the composition shown in Table 1 as a sheath, core-sheath composite spinning was carried out in the same manner as in Example 2 to form fibers and non-woven fabrics. Fiberization progressed smoothly, but the melting point of the copolyester was high and the bonding temperature was high.
It has become a non-woven fabric with a hard texture. Comparative Example 14 Core-sheath composite spinning was carried out in the same manner as in Example 2 using the composition shown in Table 1 as a sheath. Although no interfiber adhesion was observed, thread breakage occasionally occurred. Next, fiberization and non-woven fabric were carried out in the same manner as in Example 2 to obtain a non-woven fabric with a tearing length of 0.7 km. Example 8 Surlyn was added to the copolyester listed in Table 1.
A composition containing 5% by weight of 1555 is used as a sheath [η]
Core/sheath composite spinning was carried out in the same manner as in Example 2 using 0.67 PET as a core at a core/sheath weight ratio of 40/60, and stretching, shrinkage, crimping, and cutting were carried out, with a fineness of 3.3 dr and a strength of 3.5 g/d. We were able to obtain fibers with good elongation of 52% without any trouble. This composite fiber and PET fiber are blended, and the tear length is 3.2.
We were able to obtain a high-strength nonwoven fabric of Km. Example 9 Surlyn was added to the copolymerized polyester listed in Table 1.
A composition containing 5% by weight of 1555 is used as a sheath, [η]
Core/sheath composite spinning was performed in the same manner as in Example 2 using 0.67 PET as a core at a core/sheath weight ratio of 40/60, followed by stretching, shrinking, crimping, and cutting, with a fineness of 3.2 dr and a strength of 3.6 g/d. We were able to obtain fibers with a good elongation of 51% without any trouble. This composite fiber and PET fiber are blended, and the tear length is 4.0.
We were able to obtain a high-strength nonwoven fabric of Km.

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Claims (1)

[Scope of Claims] 1. As a copolymerization ratio to the total acid components, terephthalic acid is 50 mol% or more, the total of 1,4-butanediol and 1,6-hexanediol is 70 mol% or more, and the following third Contains 5-45 mol% of ingredients, melting point is 80-200℃, heat of crystal fusion is 2.0ca/g
The shortest crystallization time is within 90 seconds, and the shear strength of polyethylene terephthalate is 5Kg/
cm ² or more, and a copolymer of α-olefin and a mono- or divalent metal salt of an unsaturated carboxylic acid in an amount of 0.5 to 20% by weight based on the weight of the total composition. A fiber consisting of a composition. Here, the third component is adipic acid, sebacic acid, hydroxyacetic acid, trimethylene glycol,
Pentamethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, cyclohexanedimethanol, propylene glycol, neopentyl glycol, ethylene glycol, and isophthalic acid.