JPS60119216A - Production of polyester filament for industrial purposes - Google Patents

Abstract

PURPOSE:An epoxy compound is combined and allowed to react with a polyester, in the presence of an epoxy ring-opening catalyst and a diepoxy compound, to lower the concentration of free COOH terminal groups, then the resultant polyester is subjected spinnig to produce the titled hydrolysis-resistant and amine-resistant yarn. CONSTITUTION:(A) A polyester resin such as polyethylene terephthalate and (B) a monoepoxy compound of formula I , II (R, R' are aliphatic, alicylic or aromatic groups) such as phenyl glycidyl ether are allowed to react in the presence of an epoxy ring-opening catalyst and a diepoxy compound of formula III (R3-R8 are H, monovalent organic residue; X is divalent organic residue) such as diglycidyl terephthalate, preferably 0.01-0.05mol% based on the component A to lower the concentration of free terminal COOH groups. Then, melt-spinning is conducted to give the objective filaments.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field The present invention relates to a method for producing industrial polyester filaments. s'#shi< relates to a method for producing industrial polyester filaments which have significantly improved hydrolysis resistance and amine decomposition resistance, and which satisfy physical requirements such as strength and two-dimensional stability. More specifically, the present invention relates to a method for producing a polyester filament for industrial use, which has a low concentration of free carboxyl end groups and which improves the reduction in the degree of polymerization of polyester that occurs during the free carboxyl end group blocking reaction.

(b) Prior art polyester filaments, especially polyethylene terephrate filaments, have strength and stability in two dimensions.

Because it has excellent physical properties such as good durability and high initial modulus, it is used in many industrial fields as reinforcing cords for conhair helds, power transmission belts, bows, automobile rubber tires, etc. . In recent years, as the fields of use have expanded and diversified, various characteristics have come to be required. Specifically, the current situation is to improve strength and elongation (2) dimensional stability, glii modulus (7), mechanical fatigue resistance, and even chemical fatigue resistance.

For example, when used as a tight cord to reinforce automobile rubber tires, chemical fatigue resistance is extremely important.
It is well known among those skilled in the art that the chemical fatigue resistance of polyester tire cords is inferior to that of polyamides because the heat generated by rotation of the tire accelerates hydrolysis and amine decomposition of the polyester filaments. Since the concentration of free carboxyl end groups of the polyester is greatly involved in these decomposition reactions, it is necessary to reduce the concentration of free carboxyl end groups. Various techniques for reducing the concentration of free carboxyl terminal groups have been studied over the years, and for example, the addition of epoxy compounds, carbodiimide compounds, cyclic carbonate compounds, etc. has been proposed. For example, such technology is disclosed in Japanese Patent Application Laid-open No. 54-609.
Publication No. 8, JP-A-50-9551.7, JP-A-4
It is introduced in Publication No. 5-3911, etc.

Among the additives used in the above-mentioned known techniques, epoxy compounds are considered to be desirable for egg weight because they cause few process troubles, have good filament processability, are inexpensive, easily available, and are economically advantageous. However, as a result of detailed study by the present inventor, when an epoxy compound is reacted with polyester in the presence of an epoxy ring-opening catalyst to produce industrial polyester filaments in accordance with the trial decision, it is true that the concentration of free carboxyl end groups is Although it is possible to reduce the amount of polyester to 25 equivalents or less per 10 g of polyester, the color tone becomes yellowish and a decrease in the degree of polymerization of the polyester is observed during spinning, probably due to the epoxy ring-opening catalyst used to promote the reaction. It was confirmed that this method is very inconvenient for obtaining high-strength filaments. Regarding this phenomenon, JP-A-54-6098, JP-A-54-1326
It is also described in Publication No. 96, Japanese Unexamined Patent Publication No. 55-12871, etc.

In order to eliminate these drawbacks, it is easy to consider adjusting the degree of polymerization of the raw polyester resin at the start of spinning in anticipation of the decrease in the degree of polymerization that occurs during the addition reaction of the epoxy compound, but the time and cost required to adjust the degree of polymerization is Considering the increase, etc., this method cannot be said to be advantageous, and it does not solve the problem of the essential deterioration of physical properties.

Therefore, the present inventor attempted to apply a di-epoxy compound, which is used for improving the physical properties and molding of polyester resin, to improve the physical properties of filaments. 'ti release carboxyl terminal group concentration is 25 per 10'g of polyester.
Although it is easy to reduce the amount to less than the equivalent amount and solve the problem of a decrease in the degree of polymerization during the reaction and addition of polyester, it has become clear that ficimen 1-processability is hindered, probably due to crosslinking, and it is technically difficult to apply it. Ta.

(c) Purpose of the Invention The purpose of the present invention is to provide a method for producing industrial polyester filaments that have significantly improved hydrolysis resistance and amine decomposition resistance without lowering the degree of polymerization of polyester or interfering with filament processability. There is something to do.

(d) Structure of the Invention The method for producing industrial polyester filaments according to the present invention involves adding and reacting a heptanoepoxy compound to a polyester resin in the presence of an epoxy ring-opening reaction catalyst and a di-epoxy compound to form free carboxyl filaments. It is characterized by reducing the terminal group concentration and then spinning.

(B) Embodiment In the present invention, the term "polyester resin" refers to a polycondensate of a dibasic acid such as terephthalic acid, typified by polyethylene terephthalate, and a dihydric alcohol such as ethylene glycol. Specifically, as acid components other than terephthalic acid, phthalic acid, isophthalic acid, adipic acid, oxalic acid, cehatic acid, superic acid, glutaric acid, pimelic acid, fumaric acid, succinic acid, etc. are used, and
Polymerization degree modifiers such as propionic acid may also be used.

As the alcohol component other than ethylene glycol, polymethylene glycol having 2 to 10 carbon atoms, cyclohexane dimetatool, etc. are preferable. A small amount of the components shown below may be used in combination with these condensation components as modifiers. For example, 5-oxydimethyl isophthalate, 5-oxydimethyl hexahydroisophthalate, benzene-1,3,
1-1-ricarponic acid, paracarbomethoxyphenyldiethyl phosphate, 3,5-dicarboxyphenyldiethyl phosphate, pentaerythrol, glycerol, glycol, phosphoric acid, triphenyl phosphate,
Tri-p-carbomethoxyphenyl phosphate, tricaprylborate, sorbitan, trimesic acid, diethylene glycol, and the like.

The type of polyester resin in the present invention is not particularly limited, but it contains 80 ethylene terephthalate units.
Those containing at least mol % are preferable, and in particular, those consisting essentially of polyethylene terephthalate are most preferable. As the polycondensation method, conventionally known methods can be used as they are. Additives used in ordinary polyesters, such as matting agents and stabilizers, may also be added.

As the mono-epoxy compound in the present invention, a compound represented by the general formula (wherein R and R' are an aliphatic, alicyclic, or aromatic group) is used.

Such mono-epoxy compounds include phenyl glycidyl ether, 3-(2-xenyloxy)-1,2
-Epoxypropane, allyl glycidyl ether, butyl glycidyl ether, lauryl glycidyl ether,
Benzyl glycidyl ether, cyclohexyl glycidyl ether, α-talesyl glycidyl ether, pt
Typical examples include -butylphenylglycidyl ether, glycidyl methacrylate, styrene oxide, octylene oxide, etc., but it goes without saying that similar substances thereof may also be included. Furthermore, there is no problem in combining two or more of the above-mentioned compounds as the mono-epoxy compound.

The amount of these mono-epoxy compounds added to polyester is preferably in the range of 0.2 to 4.5 mol% (relative to polyester (hereinafter abbreviated as rPEJ)), and 0.5
A range of 3.0 mol% to 3.0 mol% (based on PE) is more desirable. If the amount of the mono-epoxy compound is too small, the desired degree of blocking of free carboxyl end groups will be low (and the effect will be weak).On the other hand, if the amount is too large, the reaction will proceed sufficiently, but the polyester filament will be colored and the degree of polymerization will be severely reduced. The effectiveness of the di-epoxy compound is also reduced by half, and troubles in the process are likely to occur, such as severe white smoke generation due to the evaporation of the 7-epoxy compound from the exit of the spinning hole.

The di-epoxy compound used in the present invention has the general formula: (wherein, R3-R4, R5p Rap R?, R8
represents a hydrogen atom or a -valent organic residue, and X represents a divalent organic residue. ) is used. Such di-epoxy compounds include terephthalic acid diglycidyl ester, tetrahydrophthalic acid diglycidyl ester, hexahydrophthalic acid diglycidyl ester, phthalic acid dimethylglycidyl ester, phenylene diglycidyl ether, diglycidyl ether, and ethylene diglycidyl ether. , trimethylene glycidyl ether, tetramethylene diglycidyl ether, hexamethylene diglycidyl ether, etc. are representative examples, but it goes without saying that similar substances thereof may also be included. Further, there is no problem in combining the above-mentioned compounds as di-epoxy compounds with a Hi4 or more.

These di-epoxy compounds are added mainly to suppress a decrease in the degree of polymerization during the addition reaction of mono-epoxy compounds, and in the present invention, the amount added is as follows:
A range of 0.005 to 0.15 mol% (based on PE) is desirable, and a range of 0.01 to 0.05 mol% (based on PE) is more desirable. If the amount of the di-epoxy compound is too small, the desired effect of suppressing a decrease in the degree of polymerization will be weak (on the contrary, if it is too large, the filament will be hindered in drawing ability and yarn breakage will occur frequently, which is not preferable).

The mono-epoxy compound, epoxy ring-opening reaction catalyst, and di-epoxy compound to be added in the present invention can be added at any timing after the polymerization step, and conventionally known methods can be used for the addition. For example, it can be mixed and added to dry chips in a rotary chip dryer or in a blender to make it adhere uniformly to the chip surface, or it can be heated at 100 to 180°C after drying in a rotary chip dryer.
Possible methods include adding it to a heated chip and allowing it to soak into the chip, or adding it during solid phase polymerization when solid phase polymerization is used to adjust the degree of polymerization, but any method is acceptable. Among various known addition methods, JP-A-49-55915
Particularly preferable is the method of adding the resin near the chip-incorporated layer of the melt spinning machine, as introduced in Japanese Patent Application Laid-Open No. 51-49917. One of the most preferred methods is to simultaneously add the epoxy ring-opening reaction catalyst and the di-epoxy compound together with the mono-epoxy compound to the melt spinning machine near one tip receptacle using a metering gear pump.

- Regarding epoxy ring-opening reaction catalysts, tertiary amines, quaternary ammonium salts, acid anhydrides, organic acid metal salts,
- Any of the known epoxy ring-opening reaction catalyst compounds, such as metal salts of basic and polybasic non-TA acids, carboxylic acid amides, etc., may be used, and there are no particular limitations.

(f) Effects of the invention Generally, it was thought that the application of di-epoxy compounds to filaments would be difficult due to polyester crosslinking, but by combining them with mono-epoxy compounds as in the present invention, There was no interference with filament processability, the decrease in the degree of polymerization when adding the mono-epoxy compound alone was solved, and the concentration of M-free carboxyl terminal θ111 groups was surprisingly reduced, probably due to the synergistic effect of both the mono- and di-epoxy compounds. Significantly larger than it should be.

The mono- and di-epoxy compounds used in the present invention are easily available, inexpensive, and economically advantageous, and do not interfere with filament processing due to by-products during spinning, and have a high degree of polymerization and remarkable chemical fatigue resistance. Its industrial value is enormous because improved filaments can be produced.

(g) Methods for measuring various properties In this specification, the measurement of [M-free carboxyl terminal group concentration] is performed using the POI method (8na1.CI+em
.

26, 1614 (1957)) and is expressed as the number of equivalents of free carboxyl end groups per log polyester.

In this specification, intrinsic viscosity [η] refers to 1 g of sample at 0C
11 (orthochlorophenol) solvent 100m 7! 35% using an improved Ubbelohde capillary viscometer.
The reduced viscosity value measured at a constant temperature of °C is converted into the intrinsic viscosity.

In this specification, "polymerization degree reduction rate" means
(%)

In this specification, "hydrolysis resistance index" refers to
This is the improvement rate (%) based on the results of Comparative Example 1 when the strength retention rate was measured after moist heat treatment for 2 hours.

Hydrolysis resistance index 1 In this specification, "amine degradation resistance index" is 180
When the strength retention rate was measured after treatment with 2.8wfy ammonia water at It was created in the same way.

(di) Examples Next, the present invention will be explained in detail by giving examples of polyethylene terephthalate, which is the most typical polyester resin. Note that "parts" shown in the examples are "parts by weight."

(Example 1) 125 parts of dimethyl terexcrate, 88 parts of ethylene glycol, 0.06 parts of manganese acetate, 0 parts of antimony trioxide
．． Bis-(
β-hydroxyethyl) telecrate content MO,
41 into a polymerization tank. to this! ;C) Add 1-0,038 parts of 1-helimethylphosphate as a stabilizer, and add 20
While gradually lowering the temperature from 0℃, the degree of vacuum was increased from 760mmt1g, and finally 290℃10,1 Dragon IIg.
Polycondensation was carried out at a pressure of . After the polycondensation reaction at a rate of about 2 hours, wait until the intrinsic viscosity of polyethylene terephthalate reaches 0.62, then finish the polycondensation reaction, pressurize the reaction system with nitrogen, discharge it, and rapidly cool and cut the discharged product. I made it into a chip. The free carboxyl end group concentration of the obtained polymer chip was 4
It was 2eq/10g.

Next, the obtained polymer chips were transferred to a solid phase polymerization reaction tank,
A solid phase polymerization reaction was carried out at 240° C. in a nitrogen stream at normal pressure until the intrinsic viscosity reached 0.95. (The concentration of free carboxyl end groups in the highly polymerized polymer tubes was 31e
q/10 g.

Highly polymerized polymer chips obtained by solid phase polymerization reaction were dissolved at 290°C in a nitrogen stream, and 0.8 mol% of phenyl glycidyl ether (relative to PE) and 0.03 mol% of diglycidyl terephthalate ester (relative to PE) were dissolved. ), as well as 0.03 mol% calcium acetate (relative to PE) in the form of 17/L/john, SIIIMPOINDUSTRIAL CO
.

LTD, TW-100B-4B was simultaneously added using a mold pump, and the mixture was allowed to react for about 10 minutes while spinning.

The obtained filament] had an intrinsic viscosity of 0.95 and a free carboxyl terminal group concentration of 22 eq/1.0 g.

(Examples 2 and 3) All procedures were carried out in the same manner as in Example 1, except that the amount of phenyl glycidyl ether added was varied as shown in Table 1. The results are not shown in Table IL.

(Examples 4 and 5) All procedures were carried out in the same manner as in Example 1, except that the amount of terephthalic acid diglycidyl ester added was varied as shown in Table 1. The results are shown in Table 1.

(Examples 6 and 7) All procedures were carried out in the same manner as in Example 1, except that the type of di-epoxy compound was changed as shown in Table 1. From the results in Table 1, it was confirmed that the effect was comparable to that of terephthalic acid diglycidyl ester.

(Example 8, 9, 10, 11) All procedures were carried out in the same manner as in Example 1, except that the type of epoxy ring-opening reaction catalyst was changed as shown in Table 1. From the results in Table 1, it was confirmed that the effect was comparable to that of Luciu Acetate J.

(Examples 12 and 13) All procedures were carried out in the same manner as in Example 1, except that the type of mono-epoxy compound was changed as shown in Table 1. From the results in Table 1, it was confirmed that the effect was comparable to that of phenyl glycidyl ether.

(Comparative Example 1) All procedures were performed in the same manner as in Example 1 except that none of the 7-epoxy compound, the epoxy ring-opening reaction catalyst, and the di-epoxy compound were added.

The results are shown in Table 1.

(Comparative Example 2) All procedures were carried out in the same manner as in Example 1, except that no mono-epoxy compound was added. As shown in Table 1, the results were poor stretchability and frequent yarn breakage.

(Comparative Example 3) All procedures were carried out in the same manner as in Example 1, except that the amount of terephthalic acid diglycidyl ester added was changed. Result is,
As shown in Table 1, the spinning was defective, probably due to crosslinking.

(Comparative Example 4) All procedures were carried out in the same manner as in Example 2 except that terephthalic acid diglycidyl ester was not added. As shown in Table 1, a decrease in the degree of polymerization of the filaments was observed.

(Comparative Examples 5, 6.7) All procedures were carried out in the same manner as in Comparative Example 4, except that the epoxy ring-opening reaction catalyst was variously changed. As shown in Table 1, a decrease in the degree of polymerization of the filaments was observed.

From Table 2, it will be clear that the effects of the present invention are surprisingly good and can only be achieved by a clever combination of mono-epoxy compounds, epoxy ring-opening reaction catalysts and di-epoxy compounds.

Below margin

Claims (1)

[Claims] 1) An industry characterized by adding and reacting a mono-epoxy compound to a polyester resin in the presence of an epoxy ring-opening reaction catalyst and a di-epoxy compound to reduce the number of free carboxyl terminal groups, and then spinning. Method for manufacturing polyester filament for use.