CN109563257B

CN109563257B - Polyester

Info

Publication number: CN109563257B
Application number: CN201780050617.6A
Authority: CN
Inventors: 成娟; 柏立军; 陈彬彬; 旦浩一; 中川顺一; 田中陽一郎
Original assignee: Toray Fibers and Textiles Research Laboratories China Co Ltd
Current assignee: Toray Industries Inc
Priority date: 2016-10-25
Filing date: 2017-10-23
Publication date: 2020-12-25
Anticipated expiration: 2037-10-23
Also published as: JP2019531395A; TWI753033B; CN109563257A; WO2018077126A1; KR20190073388A; JP6988891B2; TW201819457A; KR102356959B1; CN107973903A

Abstract

The invention discloses polyester, which is a polymer formed by taking aromatic dicarboxylic acid or derivatives thereof and aliphatic diol as main components and polyethylene glycol as a copolymerization component, wherein the number average molecular weight of the polyethylene glycol is 2000-30000 g/mol, and the copolymerization rate is 25-55 wt%. The polyester of the present invention is a fiber obtained by spinning alone or in combination with other components by a conventional spinning method, and a false twist yarn and a fiber structure formed from the same are excellent in moisture absorption. Therefore, the present invention can be used for applications requiring comfort and quality.

Description

Polyester

Technical Field

The present invention relates to a polyester having excellent moisture absorption.

Background

Polyesters have been widely used in the fields of fibers, films, plastics, etc. due to their excellent properties. However, because the polyester has regular structure and stronger hydrophobicity, compared with natural fibers such as cotton or hemp, the polyester fiber has poorer water absorption and hygroscopicity, and the application of the polyester fiber in the environment requiring the hygroscopicity is greatly limited. When the textile obtained from the polyester fiber is made into underwear, the polyester fiber is not suitable for summer clothing because the polyester fiber has poor hygroscopicity and brings stuffy feeling to people.

In order to solve the problem of poor water and moisture absorption of polyester fibers, many methods have been tried by those skilled in the art. For example, the surface of the fiber is modified mainly by making the surface of the fiber porous and then improving the moisture absorption of the fiber by the capillary principle. The modification of the fiber surface can also be achieved by methods such as electrical discharge treatment, photografting modification, low temperature plasma treatment, and the like. However, the fibers obtained by these methods do not have a good effect on reducing the steaming feeling in the sweaty state and do not have a refreshing feeling of natural fibers such as cotton and hemp when they are made into a woven fabric. In addition to these methods, there is a method of wrapping a hydrophilic film on the surface of the fiber, but this method has disadvantages that the affinity between the fiber and the film is poor and the durability after washing with water is poor.

The moisture absorption performance of the fiber can also be improved by chemically grafting the polyester fiber. For example: polyethylene terephthalate (PET) fibers were subjected to graft copolymerization of acrylic acid and methacrylic acid at a concentration of about 15%, and then to a sodium ion exchange treatment, whereby a moisture absorption rate equivalent to that of cotton was obtained. The moisture absorption speed of the fiber is very low, and the basic performance of the polyester fiber is greatly lost, so that the application value is basically not high, and the industrial production is not available.

Further, although a polyether compound having a high molecular weight is used to improve the moisture absorption, the polyether compound having a high molecular weight is not completely copolymerized with the polyester matrix, and is present in the polyester in a state of a mostly separated phase, which causes coarsening of the polymer during melt retention to form an unstable phase separation structure, and discharge after the end of the polymerization reaction and discharge from the opening part during spinning are unstable, resulting in large fineness unevenness and dyeing unevenness of the final fiber, and generation of hairiness. Japanese patent laid-open No. 2007 and 70467 discloses the use of a special PEG copolymerized with PET to improve the moisture absorption of PET. However, when the amount of PEG added is too small, high hygroscopicity is not obtained, and therefore a high amount of PEG added is required, which results in loss of basic properties of the fiber after the polyester is formed into a fiber, and also in significant deterioration of heat resistance, resistance to hot water and resistance to oxidation heat, resulting in a low use value.

Disclosure of Invention

The invention aims to provide a polyester with excellent hygroscopicity, and a fiber obtained by spinning the polyester has excellent hot water resistance and oxidation heat resistance.

The technical solution of the invention is as follows:

a polyester, the polyester is a polymer formed by copolymerization components of aromatic dicarboxylic acid or derivatives thereof and aliphatic diol as main components and polyethylene glycol as copolymerization components, wherein the number average molecular weight of the polyethylene glycol is 2000-30000 g/mol, the copolymerization rate is 25-55 wt%, and the polyester contains a semi-hindered phenol antioxidant shown as a formula 1,

wherein R1 is a group formed by combining one or more of hydrocarbon, oxygen and nitrogen; r2 is a group formed by one or more of hydrogen, hydrocarbon, oxygen and nitrogen.

The content of the semi-hindered phenol antioxidant is preferably 1.0-8.0 wt% of the total weight of the polyester.

The semi-hindered phenolic antioxidant is preferably an antioxidant 3, 9-bis [1, 1-dimethyl-2- [ (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy ] ethyl ] -2,4,8, 10-tetraoxaspiro [5.5] undecane shown in formula 2, or 1, 3, 5-tris (4-tert-butyl-3-hydroxy-2, 6-dimethylbenzyl) -1, 3, 5-triazine-2, 4, 6- (1H, 3H, 5H) -trione shown in formula 3,

the copolymerization rate of the polyethylene glycol is preferably 35-55 wt%.

The aliphatic diol is preferably ethylene glycol or 1, 4-butanediol; when the aliphatic diol is preferably ethylene glycol, the number average molecular weight of the polyethylene glycol is preferably 4000-30000 g/mol.

The copolymerization rate of polyethylene glycol in the polyester is high, the moisture absorption of polyester slices is excellent, and the difference value of the moisture absorption rate difference before and after fiber dyeing of the polyester after fiber forming is small. Meanwhile, the polyester has good heat resistance, excellent yellowing resistance and high application value.

Detailed Description

The polyester is polyether ester obtained by copolymerization of aromatic dicarboxylic acid or derivatives thereof and aliphatic diol serving as main monomers and polyethylene glycol serving as copolymerization components, and has good heat resistance and mechanical properties.

Specific examples of the aromatic dicarboxylic acid or derivative thereof include terephthalic acid, isophthalic acid, phthalic acid, sodium 5-sulfonate isophthalate, lithium 5-sulfonate isophthalate, phosphorus 5- (tetraalkyl) -isophthalate sulfonate compound, 4' -biphenyldicarboxylic acid, and 2, 6-naphthalenedicarboxylic acid, but are not limited thereto, and terephthalic acid is preferred.

Specific examples of the aliphatic diol include, but are not limited to, ethylene glycol, 1, 3-propanediol, 1, 4-butanediol, hexanediol, cyclohexane hexanediol, diethylene glycol, hexamethylene glycol, and neopentyl glycol. In particular, ethylene glycol, propylene glycol and 1, 4-butanediol are preferable because they are easy to handle during production and use. From the viewpoint of heat resistance and mechanical properties, ethylene glycol is more preferable; from the viewpoint of crystallinity, 1, 4-butanediol is more preferable.

The polyester of the present invention may have a number average molecular weight of polyethylene glycol as a copolymerization component selected as appropriate within a range where the polyester has crystallinity. The copolymerization rate of the polyethylene glycol in the polyester is 25-55 wt%. When the copolymerization ratio of polyethylene glycol is less than 25 wt%, the discharge property of polyester is poor; when the copolymerization ratio of polyethylene glycol is more than 55wt%, the physical properties of the fiber formed of the resulting polyester are degraded. Since the discharge property of the obtained polyester is general when the copolymerization rate of the polyethylene glycol is 25 to 35wt%, the copolymerization rate of the polyethylene glycol is preferably 35 to 55wt% in the present invention in order to obtain a polyester having a better discharge property.

The preferable range differs depending on the composition of the polyester. For example, in the case where the aliphatic diol constituting the polyester is ethylene glycol, if the molecular weight of the polyester is too low, the polyethylene glycol is seriously degraded due to too high polymerization temperature, and the moisture absorption rate of the final polyester, even the fiber produced therefrom, is lowered. Meanwhile, when the aliphatic diol constituting the polyester is 1, 4-butanediol, the degradation of polyethylene glycol is relatively less severe due to the low polymerization temperature than in the case of using ethylene glycol as described above, so that the moisture absorption of the polyester and even the moisture absorption after the polyester is formed into a fiber can be improved.

When the aliphatic diol is ethylene glycol, the number average molecular weight of the polyethylene glycol is preferably 4000-30000 g/mol, and the copolymerization rate of the polyethylene glycol is preferably 35-55 wt%. When the number average molecular weight of polyethylene glycol is 4000g/mol or more, the moisture absorption of polyester is high, and a fiber having excellent moisture absorption can be obtained by single spinning or composite spinning. At the same time, the decrease of crystallinity of the polyester and the decrease of extrapolated melting initial temperature can be inhibited, and the yarn breakage and hairiness after the polyester spinning are reduced, so that the engineering passing property is good, the generation of dyeing unevenness and hairiness is reduced when forming a fiber structure such as a fabric and a knit, and the quality is excellent. On the other hand, when the number average molecular weight of polyethylene glycol is 30000g/mol or less, the polycondensation reactivity is high, unreacted polyethylene glycol is reduced, elution in hot water during hot water treatment such as dyeing can be suppressed, and the hygroscopicity after hot water treatment can be maintained. The number average molecular weight of the polyethylene glycol is preferably 25000g/mol or less, more preferably 20000g/mol or less.

Meanwhile, when the copolymerization ratio of the polyethylene glycol is more than 35wt%, the moisture absorption of the polyester is high, and the fiber with excellent moisture absorption can be obtained by single spinning or composite spinning. On the other hand, when the copolymerization ratio of polyethylene glycol is 55wt% or less, the occurrence of yarn breakage and hairiness after polyester spinning is reduced, the engineering passability is good, the occurrence of dyeing unevenness and hairiness when forming a fiber structure such as a woven fabric and a knit is reduced, and the quality is excellent. At the same time, dissolution of polyethylene glycol during hot water treatment such as dyeing can be suppressed, and moisture absorption of the fiber can be maintained after the hot water treatment.

When the aliphatic diol is 1, 4-butanediol, the number average molecular weight of the polyethylene glycol is preferably 2000-30000 g/mol, and the copolymerization rate of the polyethylene glycol is preferably 35-55 wt%. When the number average molecular weight of polyethylene glycol is 2000g/mol or more, the moisture absorption of polyester is high, and a fiber having excellent moisture absorption can be obtained by single spinning or composite spinning. At the same time, the crystallinity of the polyester can be inhibited from decreasing. Meanwhile, when the number average molecular weight of polyethylene glycol is 2000g/mol or more, the decrease in crystallinity of polyester and the decrease in extrapolated melting onset temperature can be suppressed, and the occurrence of broken filaments and hairiness in elongation and false twist processes is reduced, so that the process passability is good, and the occurrence of stain and hairiness in forming a fiber structure such as a woven fabric and a knit is reduced, and the quality is excellent. On the other hand, when the number average molecular weight of polyethylene glycol is 30000g/mol or less, the polycondensation reactivity is high, unreacted polyethylene glycol is reduced, elution in hot water during hot water treatment such as dyeing can be suppressed, and the hygroscopicity after hot water treatment can be maintained. The number average molecular weight of the polyethylene glycol is preferably 27000g/mol or less, more preferably 25000g/mol or less, and most preferably 20000g/mol or less. Meanwhile, when the copolymerization ratio of the polyethylene glycol is more than 35wt%, the moisture absorption of the polyester is high, and the fiber with excellent moisture absorption can be obtained by single spinning or composite spinning. On the other hand, when the copolymerization ratio of polyethylene glycol is 55wt% or less, the occurrence of broken filaments and hairiness in the elongation and false twist process is reduced, the process passability is good, the occurrence of stain and hairiness in the formation of a fiber structure such as a woven fabric or a knitted fabric is reduced, and the quality is excellent. At the same time, dissolution in hot water during hot water treatment such as dyeing can be suppressed, and the hygroscopicity after hot water treatment can be maintained.

It is known that when a polyether compound is added in a large amount to a polyester, the polyester is produced byThe ether bond is thermally oxidized and decomposed, resulting in a great decrease in the moisture absorption property of the polyester after forming a fiber. Therefore, although a hindered phenol antioxidant is generally added in the process of synthesizing a polyester, after the polyester is made into fibers, ether bond radicals oxidized and decomposed in the process of high-temperature dyeing attack the para-position of the phenolic hydroxyl group of the hindered phenol antioxidant to generate a quinone yellow substance. Same mechanism as NO₂Yellow substances are generated after the action, so that the nitrogen oxygen fastness of the fiber is unqualified, and the service performance of the fiber is influenced. When the copolymerization rate of the polyethylene glycol is less than 25 wt%, the amount of the hindered phenol antioxidant added is generally small, so that the yellowing problem cannot be caused; however, when the copolymerization ratio of the polyethylene glycol is higher than 25 wt%, the yellowing problem becomes serious. The invention uses the semi-hindered phenol antioxidant shown in the formula 1, even if ether bond free radicals formed after thermal oxidation decomposition exist, because the ortho position of the phenolic hydroxyl group of the semi-hindered phenol antioxidant is methyl, the steric effect is small, the ether bond free radicals attack the meta position of the phenolic hydroxyl group of the semi-hindered phenol antioxidant, yellow quinine substances can not be generated,

The semi-hindered phenolic antioxidant of the present invention is preferably 3, 9-bis [1, 1-dimethyl-2- [ (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy ] ethyl ] -2,4,8, 10-tetraoxaspiro [5.5] undecane, or 1, 3, 5-tris (4-tert-butyl-3-hydroxy-2, 6-dimethylbenzyl) -1, 3, 5-triazine-2, 4, 6- (1H, 3H, 5H) -trione, and the amount added varies depending on the amount of polyethylene glycol, and the content of the semi-hindered phenolic antioxidant in the final polyester is preferably 1.0 to 8.0 wt%. If the content of the semi-hindered phenol antioxidant is too low, the oxidation resistance of the polyester formed into fibers is poor, and the moisture absorption of the polyester fibers is reduced after the polyethylene glycol is oxidized and decomposed; if the content of the semi-hindered phenol type antioxidant is too high, the polyester fiber is yellowed due to decomposition of the antioxidant itself.

In the present invention, the polyester is a polyether ester compound having a difference in moisture absorption (. DELTA.MR) of 13.0 wt% or more. The difference in moisture absorption rate (. DELTA.MR) in the present invention is a value measured by the method described in the specification. The polyester can be spun independently by a conventional spinning method or is subjected to composite spinning with other component polymers, and fibers with excellent hygroscopicity can be obtained.

In the present invention, the change of the color tone L value of the fiber obtained by the conventional single or composite spinning method is 6 or less, preferably 4 or less after the fiber is treated with hot water at 130 ℃ compared with that without the hot water treatment. On the other hand, the hue yellow value Δ YI of the fiber after the nitrogen oxygen fastness test is 10.0 or less, preferably 8.0 or less, more preferably 7.5 or less. When the delta YI is less than 7.5, the nitrogen-oxygen fastness reaches 4-5 grades, and when the delta YI is more than 7.5, the nitrogen-oxygen fastness is 4 grades.

In the synthesis of the above polyester, a compound containing a titanium element or an antimony element may be added as a catalyst. The titanium-containing catalyst has high catalytic activity, is easy to promote side reaction and affects the color tone stability of the final polyester fiber, so the adding amount of the titanium-containing catalyst is preferably controlled within the range of 10-150 ppm of the polyester in terms of titanium element. When the compound of antimony is used as a catalyst, the amount of the compound is in the range of 150 to 300ppm of the polyester in terms of antimony.

Various auxiliary modifiers may be added during the synthesis of the polyester. Specific examples of the auxiliary modifier include, but are not limited to, other types of antioxidants, phase solvents, plasticizers, ultraviolet absorbers, fluorescent brighteners, antibacterial agents, nucleating agents, heat stabilizers, antistatic agents, delustering agents, antifoaming agents, dyes, pigments, perfumes, and the like. The above-mentioned auxiliary additives may be used alone or in combination.

The extrapolated melt initiation temperature of the polyesters of the invention is above 180 ℃. The extrapolated melting start temperature of the polyester of the present invention is a value calculated by the method described in the specification. When a plurality of melting peaks are observed, the melting peak at the lowest temperature is calculated. When the extrapolated melting start temperature of the polyester is 180 ℃ or higher, the occurrence of yarn breakage and hairiness is reduced after the polyester is formed into a fiber, the engineering passability is good, the occurrence of dyeing unevenness and hairiness is reduced when a fiber structure such as a woven fabric and a knitted fabric is formed, and the quality is excellent.

The polyester of the present invention is a fiber obtained by spinning alone or in combination with other components by a conventional spinning method, and a false twist yarn and a fiber structure formed from the same are excellent in moisture absorption. Therefore, the present invention can be used for applications requiring comfort and quality. For example, the general clothing uses, sports clothing uses, bedding uses, interior decoration uses, and material uses, but are not limited to the above examples.

The present invention will be described in detail below with reference to specific examples. Meanwhile, each characteristic value in the examples was tested by the following method.

A. Moisture absorption Rate Difference (Δ MR) of polyester and fiber

Polyester and fiber as samples, first 60 degrees C hot air drying 30 minutes, in the temperature 20 ℃, humidity 65% RH constant temperature and humidity machine LHU-123 made by ESPEC, standing 24 hours, determination of the weight of the polymer (W1); subsequently, the mixture was allowed to stand in a constant temperature and humidity apparatus at 30 ℃ and 90% RH for 24 hours, and the weight of the polymer was measured as (W2). Then, the polymer was dried with hot air at 105 ℃ for 2 hours, and the weight of the polymer after the oven drying was measured to be (W3). The moisture absorption rate MR1 (%) after standing for 24 hours in an atmosphere of 20 ℃ and 65% RH from the completely dried state was calculated from the weights W1 and W3 of the polymers according to the following formula, the moisture absorption rate MR2 (%) after standing for 24 hours in an atmosphere of 30 ℃ and 90% RH from the completely dried state was calculated from the weights W2 and W3 of the polymers according to the following formula, and the moisture absorption difference (. DELTA.MR) was calculated from the following formula. Furthermore, 1 sample was measured for 5 times, and the average value was taken as the difference in moisture absorption (. DELTA.MR),

MR1(％)＝{(W1-W3)/W3}×100，

MR2(％)＝{(W2-W3)/W3}×100，

the moisture absorption difference (Δ MR) (%) MR2-MR 1.

B. Hot Water yellowing Properties of fibers

The polyester prepared in the examples, which was spun alone or in combination with other components by a conventional method to form a fiber, was subjected to hot water treatment at 130 ℃ for 20 minutes, and the obtained sample was subjected to color difference meter (USTC-datacolor) to determine the L value as L2, the L value before hot water treatment as L1, and L2-L1 as the hot water treatment yellowing value.

C. Yellowing value test of fiber

The polyester prepared in the embodiment is used as a test sample, fibers formed by single spinning or composite spinning with other components through a conventional method are put into a closed container, NOx gas generating agent (85% phosphoric acid and 2% nitrous acid aqueous solution) is put into the closed container, then the test sample and blue standard dyed cloth are put into the container, when the color of the blue standard cloth fades to the standard gray scale plate No. 3, the blue standard dyed cloth is replaced, and when the color reaches the standard gray scale plate No. 3 again, the test sample is taken out, washed for 2 times and dried. The yellowing value was determined by a Datacolor 650 spectrophotometer.

D. Copolymerization ratio of polyethylene glycol

Copolymerization ratio of polyethylene glycol: (peak area of H in ether bond/number of H in ether bond)/[ (peak area of H in ether bond/number of H in ether bond) × structural unit molecular weight of polyether compound) + (peak area of H in sodium sulfonate-containing isophthalic acid/3 molecular weight of ester formed from sodium sulfonate-containing isophthalic acid) + peak area of H in PTA/molecular weight of PET 4 + peak area of H in EG unit structure in polyester/molecular weight of EG unit structure 4 ].

E. Number average molecular weight (Mn) of polyethylene glycol contained

50mg of the sample was weighed out from the bottle, and 1mL of ammonia water was added thereto, followed by sealing and heating at 120 ℃ for 3 hours. After cooling, the sample was crushed and heated at 120 ℃ for a further 2 hours. After cooling, 1Ml of distilled water and 1.5Ml of 6M hydrochloric acid were added, and the volume was determined by using a 5Ml volumetric flask. After telecentric separation (3500 rpm. times.10 minutes), the resulting mixture was filtered through a 0.45 μm filter, and the filtrate was subjected to GPC measurement. This sample was subjected to GPC measurement under the following conditions (Alliance 2690, Waters). The number average molecular weight was determined except that impurities having a molecular weight of less than 1800 could not be separated;

a detector: RI-8020 manufactured by "DONG ソ" in Japan, sensitivity 128x

Column: TSKge1G3000PWXL I manufactured by "DONG ソ ONE" Japan

Solvent: 0.1M aqueous sodium chloride solution

Injection amount: 200 μm

Column temperature: 40 deg.C

Standard substance: polyethylene glycol ("エ - エムアル" Mn 106-101000 g/mol).

F. Content of semi-hindered phenolic antioxidant and hindered phenolic antioxidant

Pretreatment: taking 8g of polyester, and performing circulation treatment for 35 minutes by using 150ml of solvent toluene; cooling to 100 ℃ after treatment, and then pouring into a telecentric separation tube; then, performing telecentric separation, and taking the upper layer liquid to filter by using a 0.45 mu m filter; then diluting with methanol, and performing telecentric separation to obtain upper-layer liquid; finally, an internal standard was added, filtered through a 0.45 μm filter and then measured by HPLC.

And (3) HPLC determination: mobile phase A/B: methanol/water (12%); flow rate: 1.3 ml/min; column temperature: 40 degrees; wavelength of ultraviolet ray: 284 nm; time: and 15 min.

G. Extrapolated melting onset temperature

The polymer of the core component and the sheath component and the fiber obtained in the examples were used as samples, and the extrapolated melting start temperature was measured by using a Differential Scanning Calorimeter (DSC) model Q2000 manufactured by TA Instruments. First, a 5mg sample was heated from 0 ℃ to 280 ℃ at a heating rate of 50 ℃/min under a nitrogen atmosphere, and kept at 280 ℃ for 5 minutes to eliminate the heat history. Then, the temperature was rapidly cooled from 280 ℃ to 0 ℃, and then, the temperature was again raised from 0 ℃ to 280 ℃ at a rate of 3 ℃/min, the temperature was varied within a range of. + -. 1 ℃ and the temperature was raised after a temperature variation cycle of 60 seconds, and TMDSC was measured. According to JISK 7121: 1987 (method for measuring the transition temperature of plastics) 9.1, the extrapolated onset temperature of melting was calculated from the melting peak observed during the 2 nd tempering. 1 sample was measured 3 times and the average was taken as the extrapolated melting onset temperature. When a plurality of melting peaks are observed, the extrapolated melting start temperature is calculated from the melting peak on the lowest temperature side.

Example 1

Putting 10.9Kg of terephthalic acid and 4.7Kg of ethylene glycol into an esterification kettle, stirring and heating to 230 ℃ for esterification reaction, then transferring to a polycondensation kettle, adding 35wt% of polyethylene glycol 8300 (polyethylene glycol with the number average molecular weight of 8300g/mol, abbreviated as PEG8300) relative to the total amount of the final polyester, taking 250ppm of antimony trioxide relative to the total amount of the final polyester as a polymerization catalyst, adding 250ppm of trimethyl phosphate as a stabilizer relative to the total amount of the final polyester, starting to reduce the pressure and heat after 5 minutes, reaching the final temperature of 285 ℃, adding 1.0 wt% of semi-hindered phenol antioxidant 1, 3, 5-tris (4-tert-butyl-3-hydroxy-2, 6-dimethylbenzyl) -1, 3, 5-triazine-2 relative to the total amount of the final polyester into a reaction system after the final pressure reaches 285 ℃,4, 6- (1H, 3H, 5H) -trione (CN1790), stirring for 10 minutes, introducing nitrogen into the reaction system, returning to normal pressure, and stopping the polycondensation reaction to obtain the copolyester.

And carrying out melt spinning on the obtained polyester chips at the spinning speed of 3Km/min to obtain the pre-oriented yarn. Then false twisting the obtained pre-oriented yarn, wherein the processing conditions are as follows: the temperature of the first hot box is 180 ℃, the temperature of the second hot box is normal temperature, and the extension ratio is 1.7, so that the high-hygroscopicity polyester fiber is prepared. The specific physical properties of the polyester and the fiber are shown in Table 1.

Example 2

The amount of PEG8300 added was 40 wt%, and the amount of CN1790, which is a semi-hindered phenol antioxidant, added was 1.1 wt%. The rest is the same as example 1. See table 1 for details.

Example 3

PEG11000 (number average molecular weight 11000g/mol) was added in an amount of 35wt%, and CN1790, a semi-hindered phenolic antioxidant, was added in an amount of 1.0 wt%. The rest is the same as example 1. See table 1 for details.

Example 4

PEG20000 (number average molecular weight 20000g/mol) was added in an amount of 35wt%, and CN1790, a semi-hindered phenolic antioxidant, was added in an amount of 1.0 wt%. The rest is the same as example 1. See table 1 for details.

Example 5

PEG30000 (number average molecular weight 30000g/mol) was added in an amount of 35wt%, and semi-hindered phenolic antioxidant CN1790 was added in an amount of 1.0 wt%. The rest is the same as example 1. See table 1 for details.

Example 6

The amount of PEG8300 added was 35wt%, and the amount of CN1790, a semi-hindered phenol antioxidant, added was 3.0 wt%. The rest is the same as example 1. See table 1 for details.

Example 7

The amount of PEG8300 added was 35wt%, and the amount of CN1790, a semi-hindered phenolic antioxidant, added was 5.0 wt%. The rest is the same as example 1. See table 1 for details.

Example 8

The amount of PEG8300 added was 35% by weight, and the amount of semi-hindered phenolic antioxidant, 3, 9-bis [1, 1-dimethyl-2- [ (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy ] ethyl ] -2,4,8, 10-tetraoxaspiro [5.5] undecane (AO80), added was 1.6% by weight. The rest is the same as example 1. See table 1 for details.

Example 9

PEG8300 was added in an amount of 35wt%, and the semi-hindered phenolic antioxidant AO80 was added in an amount of 4.7 wt%. The rest is the same as example 1. See table 1 for details.

Example 10

PEG8300 was added in an amount of 35wt%, and the semi-hindered phenolic antioxidant AO80 was added in an amount of 8.0 wt%. The rest is the same as example 1. See table 1 for details.

Example 11

The amount of PEG8300 added was 30 wt%, and the amount of CN1790, which is a semi-hindered phenol antioxidant, added was 1.0 wt%. The rest is the same as example 1. See table 1 for details.

Example 12

The amount of PEG8300 added was 27 wt%, and the amount of CN1790, which is a semi-hindered phenolic antioxidant, added was 10.0 wt%. The rest is the same as example 1. See table 1 for details.

Example 13

Putting 10.9Kg of terephthalic acid and 11.8Kg of 1, 4-butanediol into an esterification kettle, adding 450ppm of tetrabutyl titanate catalyst relative to the total amount of the final polyester, stirring and heating to 230 ℃ for esterification, then moving to a polycondensation kettle, adding 3400 polyethylene glycol (3400 polyethylene glycol with the number average molecular weight of 3400g/mol, abbreviated as PEG3400) which is 45 wt% relative to the total amount of the final polyester, adding 900ppm of tetrabutyl titanate catalyst relative to the total amount of the final polyester, adding 250ppm of trimethyl phosphate as a stabilizer relative to the total amount of the final polyester, starting to reduce the pressure and heat after 5 minutes, reaching the final temperature of 250 ℃, adding 1.3 wt% of semi-hindered phenol antioxidant 1, 3, 5-tris (4-tert-butyl-3-hydroxy-2, 6-dimethylbenzyl) -1 relative to the total amount of the final polyester into the reaction system after reaching the final pressure, 3, 5-triazine-2, 4, 6- (1H, 3H, 5H) -trione (CN1790), stirring for 10 minutes, introducing nitrogen into the reaction system, returning to normal pressure, and stopping the polycondensation reaction to obtain the copolyester.

And carrying out melt spinning on the obtained polyester chips at the spinning speed of 3Km/min to obtain the pre-oriented yarn. Then false twisting the obtained pre-oriented yarn, wherein the processing conditions are as follows: the temperature of the first hot box is 180 ℃, the temperature of the second hot box is normal temperature, and the extension ratio is 1.7, so that the high-hygroscopicity polyester fiber is prepared. The concrete physical properties of the polyester and the fiber are shown in Table 2

Example 14

PEG3400 was added in an amount of 55wt%, and CN1790, a semi-hindered phenol antioxidant, was added in an amount of 1.4 wt%. The rest is the same as example 13. See table 2 for details.

Example 15

PEG3400 was added in an amount of 58 wt%, and CN1790, a semi-hindered phenolic antioxidant, was added in an amount of 1.8 wt%. The rest is the same as example 13. See table 2 for details.

Example 16

The addition amount of PEG11000 was 55wt%, and the addition amount of antioxidant CN1790 was 1.4 wt%. The rest is the same as example 13. See table 2 for details.

Example 17

PEG20000 was added in an amount of 55wt%, and CN1790, a semi-hindered phenolic antioxidant, was added in an amount of 1.4 wt%. The rest is the same as example 13. See table 2 for details.

Example 18

PEG3400 was added in an amount of 55wt%, and CN1790, a semi-hindered phenolic antioxidant, was added in an amount of 4.2 wt%, as in example 13. See table 2 for details.

Example 19

PEG3400 was added in an amount of 55wt%, and CN1790, a semi-hindered phenolic antioxidant, was added in an amount of 8.0wt%, as in example 13. See table 2 for details.

Example 20

PEG3400 was added in an amount of 55wt%, and the semi-hindered phenolic antioxidant 3, 9-bis [1, 1-dimethyl-2- [ (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy ] ethyl ] -2,4,8, 10-tetraoxaspiro [5.5] undecane (AO80) was added in an amount of 2.2 wt%. The rest is the same as example 13. See table 2 for details.

Example 21

PEG3400 was added in an amount of 55wt%, and the semi-hindered phenolic antioxidant AO80 was added in an amount of 6.6 wt%. The rest is the same as example 13. See table 2 for details.

Example 22

PEG3400 was added in an amount of 55wt%, and the semi-hindered phenolic antioxidant AO-80 was added in an amount of 8.0 wt%. The rest is the same as example 13. See table 2 for details.

Example 23

The amount of PEG3400 added was 50 wt%, and the amount of CN1790 added, which is a semi-hindered phenolic antioxidant, was 10.0 wt%. The rest is the same as example 13. See table 2 for details.

Example 24

After drying the polyester as an island component and polyethylene terephthalate (IV ═ 0.66) as a sea component in vacuum at 150 ℃ for 12 hours, the island component and the sea component were supplied to a screw-type composite spinning machine in a ratio of 20 wt% of the island component to 80 wt% of the sea component, and the filaments were spun at 285 ℃ and a discharge rate of 36 g/min using a sea-island composite spinning nozzle (24 islands in one discharge hole). The spun yarn was cooled with cold air having an air temperature of 20 ℃ and an air speed of 20 m/min, and was fed and collected by an oil feeder, stretched by a 1 st roller rotating at 2500 m/min, and wound by a 2 nd roller rotating at the same speed as the first roller, to obtain 144dtex-36f undrawn yarn. Then, the obtained undrawn yarn was subjected to draw false twisting at a heater temperature of 170 ℃ and a magnification of 1.7 times by using a draw false twister (twisting part: friction disk type, heater part: contact type) to obtain a false twisted yarn of 84dtex-36 f.

The evaluation results of the fiber properties, fabric properties and engineering passability of the obtained fibers are shown in table 3. The number of broken filaments in false twisting is 0, and the engineering passing ability is extremely good. Meanwhile, the hygroscopicity of the product is not reduced basically after the hot water treatment, and the hygroscopicity of the product is good after the hot water treatment. Moreover, the leveling property and the quality reach the qualified level. See table 3 for details.

Example 25

The semi-hindered phenolic antioxidant CN1790 was added in an amount of 3.0 wt%, as in example 24. See table 3 for details.

Example 26

The semi-hindered phenolic antioxidant CN1790 was added in an amount of 5.0 wt%, as in example 24. See table 3 for details.

Example 27

PEG8300 was added in an amount of 45 wt%, and CN1790, a semi-hindered phenol antioxidant, was added in an amount of 5.0 wt%, as in example 24. See table 3 for details.

Example 28

PEG8300 was added in an amount of 55wt%, and CN1790, a semi-hindered phenol antioxidant, was added in an amount of 5.0 wt%, as in example 24. See table 3 for details.

Example 29

The semi-hindered phenolic antioxidant AO80 was added in an amount of 1.6 wt%, as in example 24. See table 3 for details.

Example 30

The semi-hindered phenolic antioxidant AO80 was added in an amount of 4.7 wt%, as in example 24. See table 3 for details.

Example 31

The semi-hindered phenolic antioxidant AO80 was added in an amount of 8.0wt%, as in example 24. See table 3 for details.

Example 32

The semi-hindered phenolic antioxidant CN1790 was added in an amount of 2.0 wt%, as in example 24. See table 3 for details.

Example 33

The semi-hindered phenolic antioxidant AO80 was added in an amount of 4.0 wt%, as in example 24. See table 3 for details.

Example 34

The semi-hindered phenolic antioxidant AO80 was added in an amount of 6.0 wt%, as in example 24. See table 3 for details.

Example 35

The semi-hindered phenolic antioxidant CN1790 was added in an amount of 9.0 wt%, as in example 24. See table 3 for details.

Example 36

The semi-hindered phenolic antioxidant CN1790 was added in an amount of 0.9 wt%, as in example 24. See table 3 for details.

Example 37

Putting 10.9Kg of terephthalic acid and 11.8Kg of 1, 4-butanediol into an esterification kettle, adding 450ppm of tetrabutyl titanate catalyst relative to the total amount of the final polyester, stirring and heating to 230 ℃ for esterification, moving to a polycondensation kettle, adding 50 wt% of polyethylene glycol 8300 (polyethylene glycol with the number average molecular weight of 8300g/mol, abbreviated as PEG8300) relative to the total amount of the final polyester, adding 900ppm of tetrabutyl titanate catalyst relative to the total amount of the final polyester, adding 250ppm of trimethyl phosphate as a stabilizer relative to the total amount of the final polyester, starting to reduce the pressure and heat after 5 minutes, reaching the final temperature of 250 ℃, adding 1.3 wt% of semi-hindered phenol antioxidant 1, 3, 5-tris (4-tert-butyl-3-hydroxy-2, 6-dimethylbenzyl) -1 relative to the total amount of the final polyester into the reaction system after the final pressure is reached, 3, 5-triazine-2, 4, 6- (1H, 3H, 5H) -trione (CN1790), stirring for 10 minutes, introducing nitrogen into the reaction system, returning to normal pressure, and stopping the polycondensation reaction to obtain the copolyester. The rest is the same as example 24. See table 4 for details.

Example 38

The semi-hindered phenolic antioxidant CN1790 was added in an amount of 2.4 wt%, as in example 37. See table 4 for details.

Example 39

The semi-hindered phenolic antioxidant CN1790 was added in an amount of 4.2 wt%, as in example 37. See table 4 for details.

Example 40

The semi-hindered phenolic antioxidant CN1790 was added in an amount of 8.0wt%, as in example 37. See table 4 for details.

EXAMPLE 41

The semi-hindered phenolic antioxidant AO80 was added in an amount of 2.2 wt%, as in example 37. See table 4 for details.

Example 42

The semi-hindered phenolic antioxidant AO80 was added in an amount of 6.6 wt%, as in example 37. See table 4 for details.

Example 43

The amount of PEG8300 added was 45% by weight, and the amount of the semi-hindered phenolic antioxidant AO80 added was 6.6% by weight, as in example 37. See table 4 for details.

Example 44

PEG8300 was added in an amount of 55wt%, and the semi-hindered phenolic antioxidant AO80 was added in an amount of 6.6 wt%, as in example 37. See table 4 for details.

Example 45

The amount of PEG8300 added was 50% by weight, and the amount of the semi-hindered phenolic antioxidant AO80 added was 8.0% by weight, as in example 37. See table 4 for details.

Example 46

PEG8300 was added in an amount of 50 wt%, and CN1790, a semi-hindered phenol antioxidant, was added in an amount of 2.0 wt%, as in example 37. See table 4 for details.

Example 47

PEG8300 was added in an amount of 50 wt%, and CN1790, a semi-hindered phenol antioxidant, was added in an amount of 3.0 wt%, as in example 37. See table 4 for details.

Example 48

PEG8300 was added in an amount of 50 wt%, and CN1790, a semi-hindered phenol antioxidant, was added in an amount of 5.0 wt%, as in example 37. See table 4 for details.

Example 49

The amount of PEG8300 added was 50% by weight, and the amount of the semi-hindered phenolic antioxidant AO80 added was 4.0% by weight, as in example 37. See table 4 for details.

Example 50

The amount of PEG8300 added was 50% by weight, and the amount of the semi-hindered phenolic antioxidant AO80 added was 6.0% by weight, as in example 37. See table 4 for details.

Example 51

PEG8300 was added in an amount of 50 wt%, and CN1790, a semi-hindered phenol antioxidant, was added in an amount of 9.0 wt%, as in example 37. See table 4 for details.

Comparative example 1

The amount of PEG8300 added was 12 wt%, and the amount of CN1790, which is a semi-hindered phenol antioxidant, added was 1.0 wt%, as in example 1. See table 5 for details. Since the amount of PEG added is relatively small, the effect of high hygroscopicity is not obtained.

Comparative example 2

The amount of PEG8300 added was 20 wt%, and the amount of CN1790, which is a semi-hindered phenol antioxidant, added was 1.0 wt%, as in example 1. See table 5 for details. Since the amount of PEG added is relatively small, the effect of high hygroscopicity is not obtained.

Comparative example 3

PEG100000 (number average molecular weight 100000g/mol) was added in an amount of 30 wt%, and semi-hindered phenolic antioxidant CN1790 was added in an amount of 2.0 wt%, as in example 1, except the above. See table 5 for details. Due to the addition of ultra-high molecular weight PEG, the discharge is swollen and difficult to discharge.

Comparative example 4

PEG3400 was added in an amount of 12 wt%, and CN1790, a semi-hindered phenol antioxidant, was added in an amount of 0.8 wt%, as in example 13. See table 5 for details. Since the amount of PEG added is relatively small, the effect of high hygroscopicity is not obtained.

Comparative example 5

PEG3400 was added in an amount of 70 wt%, and CN1790, a semi-hindered phenolic antioxidant, was added in an amount of 4.6 wt%, as in example 13. See table 5 for details. The addition amount of PEG3400 is too high, resulting in a low extrapolated melting start temperature of the final polyester, a large amount of broken filaments and hairiness after the polyester is formed into fibers, poor engineering passability, and a large amount of dyeing unevenness and hairiness when forming fiber structures such as fabrics and knittings, and poor quality.

Comparative example 6

PEG600 (number average molecular weight 600g/mol) was added in an amount of 50 wt%, and CN1790, a semi-hindered phenolic antioxidant, was added in an amount of 3.3 wt%, as in example 13. See table 5 for details. PEG has a low molecular weight and scatters in a large amount during polymerization, and the resulting polyester has poor hygroscopicity even when a large amount is added.

Comparative example 7

PEG100000 and CN1790, which are semi-hindered phenolic antioxidants, were added in amounts of 50 wt% and 3.3 wt%, as in example 13. See table 5 for details. Due to the addition of ultra-high molecular weight PEG, the discharge is swollen and difficult to discharge.

Comparative example 8

PEG3400 was added in an amount of 20 wt%, and CN1790, a semi-hindered phenolic antioxidant, was added in an amount of 1.0 wt%, as in example 13. See table 5 for details. Since the amount of PEG added is relatively small, the effect of high hygroscopicity is not obtained.

Comparative example 9

The amount of PEG8300 added was 20 wt%, and the amount of hindered phenol type antioxidant … … (IR1010) added was 0.5 wt%, as in example 1. See table 5 for details. Hindered phenolic antioxidants tend to cause yellowing of the polyester compared to hindered phenolic antioxidants. When the amount of PEG added is small, although only a small amount of hindered phenol antioxidant pentaerythritol tetrakis [ beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate ] IR1010 needs to be added, the yellowing index of the polyester is within an acceptable range, the antioxidant effect of the polyester is reduced, the difference of the moisture absorption rate difference of the polyester fiber before and after dyeing is large, and the moisture absorption rate of the polyester fiber after dyeing is obviously reduced.

Comparative example 10

The amount of PEG8300 added was 50 wt%, and the amount of IR1010, a hindered phenol antioxidant, added was 3.0 wt%, as in example 1. See table 5 for details. When a large amount of hindered phenol-based antioxidant is added, the fiber is likely to be yellowed although the antioxidant effect is excellent.

Comparative example 11

The amount of PEG8300 added was 50 wt%, and the amount of IR1010, a hindered phenol antioxidant, added was 0.5 wt%, as in example 1. See table 5 for details. When a small amount of hindered phenol-based antioxidant is added, the yellowing of the fiber can be suppressed, but the antioxidant effect is lowered.

Comparative example 12

The same as in example 13 was repeated except that PEG3400 was added in an amount of 20 wt% and IR1010, a hindered phenol antioxidant, was added in an amount of 0.5 wt%. See table 5 for details. Hindered phenolic antioxidants tend to cause yellowing of the polyester compared to hindered phenolic antioxidants. When the amount of PEG added is small, although the yellowing index of the polyester is within an acceptable range by only adding a small amount of hindered phenol antioxidant IR1010, the antioxidation effect of the polyester is reduced, the difference of the moisture absorption rate difference of the polyester fiber before and after dyeing is large, and the moisture absorption rate of the polyester fiber after dyeing is obviously reduced.

Comparative example 13

The same as in example 13 except that the amount of PEG3400 was 50 wt% and the amount of IR1010, a hindered phenol antioxidant, was 3.0 wt%. See table 5 for details. When a large amount of hindered phenol-based antioxidant is added, the fiber is likely to be yellowed although the antioxidant effect is excellent.

Comparative example 14

The same as in example 13 except that PEG3400 was added in an amount of 50 wt% and IR1010, a hindered phenol antioxidant, was added in an amount of 0.5 wt%. See table 5 for details. When a small amount of hindered phenol-based antioxidant is added, the yellowing of the fiber can be suppressed, but the antioxidant effect is lowered.

Example 15

The amount of PEG8300 added was 22 wt%, and the amount of CN1790, which is a semi-hindered phenol antioxidant, added was 1.0 wt%, as in example 1. See table 5 for details. The addition amount of PEG8300 was not appropriate, resulting in deterioration of the ejection property.

Example 16

The amount of PEG8300 added was 25 wt%, and the amount of CN1790, which is a semi-hindered phenol antioxidant, added was 1.0 wt%, as in example 1. See table 5 for details. The addition amount of PEG8300 was not appropriate, resulting in deterioration of the ejection property.

Comparative example 17

The same as in example 24 except that the amount of PEG8300 added was 50 wt% and the amount of IR1010, a hindered phenol antioxidant, added was 3.0 wt%. See table 6 for details. In the case of composite spinning, when a large amount of hindered phenol antioxidant is added, the fiber is likely to be yellowed although the antioxidant effect is excellent.

Comparative example 18

The same as in example 24 except that the amount of PEG8300 added was 50 wt% and the amount of IR1010, a hindered phenol antioxidant, added was 0.8 wt%. See table 6 for details. In the case of composite spinning, when a small amount of hindered phenol-based antioxidant is added, the yellowing of the fiber can be suppressed, but the antioxidant effect is reduced.

Comparative example 19

The amount of PEG8300 added was 50 wt%, and no antioxidant was added, as in example 24. See table 6 for details. Since no antioxidant is added, the fiber is not yellowed, but has no antioxidant effect.

Claims

1. A polyester characterized by: the polyester is a polymer formed by taking aromatic dicarboxylic acid or derivatives thereof and aliphatic diol as main components and polyethylene glycol as a copolymerization component, wherein the number average molecular weight of the polyethylene glycol is 2000-30000 g/mol, the copolymerization rate is 25-55 wt%, and the polyester contains a semi-hindered phenol antioxidant shown as a formula 1,

in the formula 1, the compound is shown in the specification,

wherein R1 is a group formed by combining one or more of hydrocarbon, oxygen and nitrogen; r2 is a group formed by one or combination of hydrogen, hydrocarbon, oxygen and nitrogen;

the content of the semi-hindered phenol antioxidant accounts for 2.35wt% -8.0 wt% of the total weight of the polyester.

2. The polyester according to claim 1, characterized in that: the semi-hindered phenol antioxidant is an antioxidant 3, 9-bis [1, 1-dimethyl-2- [ (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy ] ethyl ] -2,4,8, 10-tetraoxaspiro [5.5] undecane shown in a formula 2, or 1, 3, 5-tris (4-tert-butyl-3-hydroxy-2, 6-dimethylbenzyl) -1, 3, 5-triazine-2, 4, 6- (1H, 3H, 5H) -trione shown in a formula 3,

in the formula (2), the first and second groups,

and (3) formula.

3. The polyester according to claim 1, characterized in that: the copolymerization rate of the polyethylene glycol is 35-55 wt%.

4. The polyester according to claim 3, characterized in that: the aliphatic diol is ethylene glycol, and the number average molecular weight of the polyethylene glycol is 4000-30000 g/mol.

5. The polyester according to claim 3, characterized in that: the aliphatic diol is 1, 4-butanediol.