CN1303127C - Copolymeization palyester polymer of copolymerized by hexamethylene and deep dyed copolymerization polyester fibre prepared by it - Google Patents

Abstract

The invention discloses a copolyester polymer for fibers produced according to a polyester polymerization process using terephthalic acid as a main raw material, and a deep dyeable copolyester fiber produced from the copolyester polymer. The copolyester polymer is obtained by copolymerizing cyclohexane 1,4-dimethanol with a diol component of 1-10 mole%, and the copolyester polymer contains 0.7-2.0wt% diethylene glycol Alcohol (DEG).

Description

Copolyester polymer obtained by copolymerization with cyclohexane 1,4-dimethanol and deep dyeable copolyester fiber prepared by using it

technical field

The present invention relates to a copolyester polymer for fibers, which is obtained by copolymerizing cyclohexane 1,4-dimethanol at 1-10 mol% based on the diol component, and relates to A deep dyeable copolyester fiber prepared using the copolyester polymer.

Background technique

Polyethylene terephthalate (PET) has excellent physical properties and good resistance to chemicals or the environment, and is generally used as a polymer material as a raw material for producing fibers for clothing, industrial fibers, and films.

Despite these excellent physical and chemical properties, polyethylene terephthalate (PET) lacks functional groups that affect dyeing when polyester fibers are used to produce garments. Therefore, the polyester fiber can be dyed by a single disperse dye that penetrates into the amorphous region of the polyester fiber and adheres thereto.

Much research has been done to enlarge the amorphous region of polyester fibers to efficiently dye polyester fibers using disperse dyes.

In general, copolyester polymers can be deeply dyed because it has larger amorphous regions than PET.

However, only improving the bathochrome performance of PET will reduce its excellent thermal stability, thereby reducing the color fastness of PET.

For example, "Modified Polyester Fiber" published by J.Miliky et al. on Elsevier in 1991 disclosed that the copolyester obtained by copolymerization with isophthalic acid or diethylene glycol has improved dyeing properties because of its amorphous The region expands, but its color fastness is reduced, which is due to changes in thermal properties, such as the reduction of melting point and glass transition temperature, which will speed up the movement of molecular chains.

In addition, some methods suggest the use of aromatic diacids such as naphthalene 2,6-dicarboxylic acid or ethylene oxide adducts of aromatic diols such as bisphenol A to increase the glass transition temperature of copolyester fibers, thereby improving Dyeability of copolyesters.

For example, Japanese Invention Unexamined Publications Sho.57-63325, Sho.57-66119, Sho.57-121032 and Sho.57-212228 mention a method in which only the ethylene oxide adduct of bisphenol A or Mixtures of ethylene oxide adducts of bisphenol A with other monomers such as neopentyl glycol are used to expand the amorphous regions of PET. However, the disadvantage of the above-mentioned method is that the use of a large amount of monomers to manufacture copolyester fibers will cause the crystallinity of the copolyester fibers to be greatly reduced, thereby making the production of the copolyester fibers difficult, or making the copolyester fibers very High shrinkage, which in turn makes copolyester fibers have lower physical properties than conventional PET.

Meanwhile, US Patents 5,681,981 and 6,342,579, PCT Publications 98/58008, 95/00575 and 97/30102, and European Patent 1,156,070 disclose methods of copolymerizing cyclohexane 1,4-dimethanol.

However, since the copolyester polymer is prepared using more than 10 mole % of cyclohexane 1,4-dimethanol, the copolyester polymer is crystalline, so even if the copolyester polymer can be used to make fibers, the The shrinkage of the fibers is also much higher than that of conventional PET fibers. Therefore, fibers made from this copolyester polymer cannot be used in place of conventional PET fibers. In particular, when 30% or more of cyclohexane 1,4-dimethanol is used to prepare the copolyester polymer, the copolyester polymer cannot be used to prepare fibers because the copolyester polymer has little crystallization zone.

Also, when the molar ratio of the diol component to the diacid component is 1.7 or higher, the yield of diethylene glycol (hereinafter referred to as DEG) is greatly increased due to side reactions in the polyester copolymerization process, and thus does not The thermal properties of the copolyester polymer are desirably reduced.

Summary of the invention

Therefore, keeping in mind the above-mentioned problems arising in the prior art, the object of the present invention is to provide a copolyester polymer for fibers having an enlarged amorphous region while ensuring that it has the excellent thermal properties of PET to Capable of being deeply dyed, the present invention also provides a deep-dyeable copolyester fiber produced using the copolyester polymer.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

According to the present invention, the present inventors have carried out intensive and comprehensive research to obtain an improved copolyester polymer, thereby achieving the above object of the present invention, and have invented a copolyester polymer which has enlarged amorphous regions and simultaneously vitrified The transition temperature does not decrease.

Examples of monomers useful in the preparation of copolyester polymers according to the present invention include aromatic or aliphatic compounds such as naphthalene dicarboxylic acid, ethylene oxide adducts of bisphenol A, or cyclohexane 1,4-di Methanol.

In particular, the present invention utilizes cyclohexane 1,4-dimethanol as a monomer in consideration of economic efficiency and shrinkage of raw yarns made using the monomer.

Cyclohexane 1,4-dimethanol may exist in isomeric forms such as cis-isomers and trans-isomers. Therefore, when using cyclohexane 1,4-dimethanol as a component to prepare a copolyester polymer, even if the amount of cyclohexane 1,4-dimethanol is small compared with other monomers, the copolymerization is more The amorphous region of the ester polymer is also sufficiently enlarged.

A detailed description of the preparation of copolyester polymers according to the present invention will be given below.

The copolyester polymer of the present invention is obtained by copolymerizing cyclohexane 1,4-dimethanol (hereinafter referred to as CHDM) in an amount of 1-10 mole % based on the diol component.

When the copolyester polymer is prepared using more than 10 mole % of CHDM, the copolyester fiber produced using the copolyester polymer has a very high degree of shrinkage. In particular, when the copolyester polymer is prepared using more than 30 mole % of CHDM, the amorphous region of the copolyester polymer becomes too large, so that the copolyester polymer cannot be used to produce copolyester fibers.

On the other hand, when less than 1 mole % of CHDM is used to prepare the copolyester polymer, the objective of the present invention to increase the amorphous region of the copolyester polymer is not achieved.

According to the present invention, the copolyester polymer is prepared by a TPA polymerization method using terephthalic acid (hereinafter referred to as TPA) as a raw material. The preparation method of the copolyester polymer can be divided into: a method using TPA as a raw material, and another method using dimethyl terephthalate as a raw material. Among them, in view of economic benefits, the method of using TPA as a raw material is very competitive.

In the process of making CHDM-containing copolyester polymers, unreacted TPA is insoluble and infusible. Therefore, unreacted TPA clogs the oligomer filter or polymer filter of the polymerization equipment, or when the copolyester polymer is spun, the filling pressure increases rapidly due to unreacted TPA, causing Reduced processability during the manufacture of materials and fibers.

Therefore, the esterification time must be long enough and the esterification temperature must be high enough to reduce the amount of unreacted TPA.

However, when the esterification time is too long or the temperature is too high, the production of DEG as a by-product disadvantageously increases, reducing the thermal stability of the copolyester polymer. Therefore, it is preferable to reduce the G value (the ratio of the total moles of ethylene glycol and CHDM to the moles of terephthalic acid) as low as possible to suppress the generation of DEG. According to the invention, the G value is in the range of 1.10 to 1.50. When the G value is within the above range, the DEG content in the copolyester polymer is 0.7 to 2.0 wt%, thus achieving the purpose of increasing the amorphous region of the copolyester polymer in the present invention. Here, the thermal properties of the copolyester polymer are not degraded, so that no problem occurs in the false twisting process during the preparation of copolyester fibers using the copolyester polymer.

Since the copolyester polymer according to the present invention is mainly used in the production of fibers for clothing, anatase-type titanium dioxide may be added to the copolyester polymer as in conventional polyesters.

In particular, no anatase titanium dioxide was added to the copolyester polymer when making superbright fibers. However, when optical fibers, semi-dull fibers, and fully-dull fibers are prepared, the amount of anatase-type titanium dioxide added to the copolyester polymer is 200 to 500 ppm, 1,000 to 5,000 ppm, and 10,000 to 40,000 ppm, respectively.

In addition, barium sulfate can be added to the copolyester polymer in an amount of 5 wt% or less based on the weight of the copolyester polymer to increase the specific gravity of the copolyester fiber, or to improve the transparency of the copolyester fiber and friction properties.

Examples of the polycondensation catalyst include antimony-based catalysts such as antimony trioxide and antimony acetate; germanium-based catalysts such as germanium dioxide; and titanium-based catalysts such as tetrabutyl titanate and tetraisopropyl titanate.

The amount of polycondensation catalyst used to prepare the copolyester polymer is from 0.01 to 5 wt%, based on the weight of the copolyester polymer.

According to the examples of the present invention and the comparative examples, the physical properties of the raw yarn samples were measured according to the following methods.

1.I.V.(dl/g): Intrinsic viscosity (I.V.) of copolyester polymer sample is measured at 30°C using phenol and 1,1,2,2-tetrachloroethane in a mixing ratio of 60/40 The solution was measured using an Ubbelohde viscometer.

2. Density: The density of the copolyester polymer samples was determined using a density gradient column comprising carbon tetrachloride and n-hexane.

3. Melting point (Tm) and glass transition temperature (Tg): The melting point and glass transition temperature of the copolyester polymer sample are DSC7 manufactured by Perkin Elmer, Inc. While heating up at a speed of 10°C/min, Determined analytically by peaks in the melting range.

4. Dyeability: The circular knitting process was applied to the raw yarn sample, and the synthetic polyvinyl acetal fiber (Kuralon) navy blue was dyed at 130°C. The coloring strength of each dyed knitted fabric was obtained by calculating the K/S value measured by a spectrophotometer.

Having generally described the present invention, the present invention can be further understood by referring to the Examples and Comparative Examples, which are provided herein for illustration only and are not intended to limit the present invention unless otherwise specified. .

Examples 1 to 3 and Comparative Examples 1 and 2

Copolyester polymers copolymerized with CHDM comprising a predetermined content of DEG are provided. At this time, the amount of CHDM is described in Table 1.

In this regard, copolyester polymers are produced in a semi-batch mode using conventional esterification units equipped with distillation reflux columns for the preparation of polymeric polyesters.

The anatase type Hombitan LW-SU for semi-dull fiber produced by Sachtleben Chemie GmbH. of Germany is used as a matting agent in an amount of 0.3wt% by copolyester polymer weight to prepare copolyester polymer, The ladder of trioxide was used as catalyst in an amount of 300 ppm by weight of the copolyester polymer. The physical properties of the copolyester polymers are described in Table 1.

The copolyester polymer was spun at a speed of 2600 m/min and drawn at the draw ratios described in Table 1 to obtain a raw copolyester yarn of 75 denier/36 filaments. The physical properties of the copolyester raw yarn were measured, and the results are shown in Table 1.

The obtained raw yarn is subjected to a circular knitting process, and dyed with polyvinyl acetal fiber navy blue at 130°C. The K/S values measured using a spectrophotometer were calculated to estimate the coloring strength of each dyed knitted fabric, and the results are shown in Table 1.

Table 1 Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 CHDM (mole%) 3 6 9 5 30 ^* G value 1.20 1.20 1.20 1.80 1.20 IV(dl/g) 0.631 0.628 0.617 0.627 0.572 DEG content (wt%) 1.28 1.34 1.46 2.46 1.78 Drawing ratio (%) 1.607 1.607 1.652 1.607 Can't spin Toughness (g/d) 3.98 3.86 3.71 3.91 - elongation(%) 41 44 43 39 - Density (g/cm ³ ) 1.3559 1.3541 1.3471 1.3550 - ^** K/S 5.84 6.15 6.82 6.12 -

^* G value: (EG+CHDM)/TPA molar ratio

^** K/S: The K/S of regular polyethylene phthalate is 4.96

As apparent from the foregoing description, the present invention provides a copolyester polymer copolymerized with 1-10 mole % of CHDM and containing 0.7-2.0 wt % of DEG. Therefore, copolyester fibers produced with the copolyester polymer can be more deeply dyed than conventional PET fibers while ensuring the same excellent physical properties as conventional PET fibers.

In addition, because the copolyester polymer is produced by the TPA polymerization process, the production cost of the copolyester polymer is low, and the copolyester fiber produced from the copolyester polymer has excellent false twist processing sex.

Although the preferred embodiment of the present invention has been disclosed for illustration, it will be appreciated by those skilled in the art that various changes, additions and modifications may be made without departing from the scope and spirit of the invention as disclosed in the appended claims. and replace.

Claims (1)

1. one kind is passed through the method that the terephthalic acid polymerization technique is produced copolyester polymer, described method comprises and the hexanaphthene 1 of counting 1-10mole% by diol component, the copolymerization of 4-dimethanol, wherein being positioned at 1.10-1.50 by adjusting G value scope makes copolyester polymer comprise the Diethylene Glycol of 0.7-2.0wt%, described G value is ethylene glycol and hexanaphthene 1, the ratio of the total mole number of 4-dimethanol and the mole number of terephthalic acid.