JPS60188421A - Copolyester - Google Patents

Abstract

PURPOSE:An aromatic polyester having melt moldability and an excellent balance between optical anisotropy and mechanical properties represented by a high modulus of elasticity, comprising specified three kinds of structural units derived from alcohols and carboxylic acids. CONSTITUTION:A copolyester comprising structural units ( I ), (II), and (III) represented by formulas I , II, and III, respectively, wherein units ( I ) amount to 20-85mol%, based on the total, and units (II)+(III) amount to 80-15mol%, based on the total. In said polyester, structural unit ( I ) is a structural unit of a polyester formed from p-hydroxybenzoic acid, structural unit (II) is a structural unit of a polyester formed from 2,7-dihydroxy-naphthalene and 4,4'-diphenyldicarboxlic acid, and structural unit (III) is a structural unit of a polyester formed from 2,7-dihydroxynaphthalene and terephthalic acid.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel aromatic polyester that can be melt-molded at temperatures below 400° C. and can provide molded articles having excellent mechanical properties and optical anisotropy.

In recent years, there has been an increasing demand for higher performance plastics, and many polymers with various new properties have been developed and put on the market. Among them, polymers with optical anisotropy, which is characterized by parallel arrangement of molecular chains, are particularly popular. Liquid crystalline polymers with excellent mechanical properties are commercially available under the trade name. However, it has been found that these p-hydroxybenzoic acid homopolymers and copolymers have too high a melting point to be melt moldable, and have high stiffness and melt viscosity, resulting in poor moldability. Therefore, a method of copolymerizing p-hydroxybenzoic acid with various components to lower its melting point has been investigated. Method of copolymerizing acids (Published Patent Publication 1986-5)
0021.5), p-hydroxybenzoic acid with 2,6-
A method of copolymerizing cyhydroxynaphthalene and terephthalic acid (Japanese Unexamined Patent Publication No. 54-50594) and a method of copolymerizing p-hydroxybenzoic acid with 2,6-; Patent No. 4, 2
24.433) etc. have been fabricated.

However, although the aromatic polyester obtained by these methods has a relatively low melting point of 400°C or less, the fluidity of the polymer is insufficient, and even better fluidity is required. -hydroxybenzoic acid,
2,7'; 1 j':'j ; The present invention has been accomplished by discovering that an aromatic polyester having a specific structure consisting of hydroxybuttalene, 4,4'-diphenyldicarboxylic acid, and terephthalic acid satisfies the above object. reached.

That is, the present invention consists of the following structural units +1+, (old and tm+, and the unit (1) is 20 to 85 mol% of the total,
The present invention provides a melt-moldable aromatic polyester characterized in that the units (1+ + (111) account for 80 to 15 mol% of the total.

In the aromatic polyester of the present invention, the structural unit i
ll is a structural unit of the polyester produced from p-hydroxybenzoic acid, and the above structural unit tll is produced from 2゜7-hydroxynaphucleno and 4,4'-diphenyldicarphonic acid and is a structural unit of the polyester. The above structural unit (flit) means a structural unit of a polyester produced from 2.7-hydroxy 3-naphthalene and terephthalic acid.

The aromatic polyester of the present invention has a melting point of 400° C. or lower, and can be easily molded into fibers, films, various molded products, etc. having excellent mechanical properties by ordinary melt molding.

Since the polyaryl 1- containing 2,7-hydroxynaphthaleno of the present invention does not have very good symmetry, it becomes an optically anisotropic polyester with good fluidity.
Very specific, for example Macromolecule
s, 16f7) ] 032 ('83), W
, by Jerome Jackson, Jr.
．． "A polyarylate consisting of 7-hydroxynaphthalene and terephthalic acid clearly does not form a liquid crystal." Therefore, the present invention is completely unexpected based on conventional knowledge.

In the aromatic polyester of the present invention, the proportion of the J2 structural unit (1) is 0 to 85 mol% of the total, particularly 0
-80 mol% is preferable, and when it exceeds 85 mol%, the melting point of the aromatic polyester is high and melt flow is reduced.41 The copolymerized polyester of the present invention has a melt viscosity of 50 to 10.
Preferably OOO poise, especially 100 poise
~6,000 poise is preferred.

What is melt viscosity here? (Liquid crystal start temperature -40~80℃)
Slip speed 2,000 to 4,000 (1,/sec) at a temperature of
This is a value measured using a Koka type flow tester under the following conditions.

That is, when the melt viscosity is lower than 50 poise, the strength of the molded product obtained is low, and when it is higher than 1.0,000 poise, the moldability is poor and the mechanical properties of the molded product tend to be poor. show.

The aromatic polyester of the present invention can be produced according to the conventional polyester polycondensation method, and there are no particular restrictions on the production method, but typical production methods include the following (1) to (3).
) law.

(1) Diesters of dihydroxynaphthalene such as p-acet-1-quinebenzoic acid and 2,7-cyacetate-1, propionate, and 4.4
A method for producing from '-diphenyl dicarboxylic acid and terephthalic acid by demonocarboxylic acid polycondensation reaction.

+2+ A method for producing by dephenol condensation from 2.7-dihydroxynaphthalene, phenyl ester of p-oxybenzoic acid, 4,4'-diphenyldicarboxylic acid, and diphenyl ester of terephthalic acid (this page, bottom blank).

(3) After reacting p-oxybenzoic acid with 4.4'-*phenyldicarboxylic acid and terephthalic acid with desired amounts of diphenylcarbonate-I to form diphenyl esters, 2.7-dihydroxynaphthalene was added. A method of manufacturing by addition and dephenol polycondensation reaction.

Typical catalysts used in the polycondensation reaction are metal compounds such as stannous acetate, tetrabutyl titanate, tl'Jium acetate, and antimony trioxide. , 3,3'-diphenyldicarboxylic acid, 3,4'-diphenyldicarboxylic acid, 2.2
Aromatic dicarboxylic acids such as '-diphenyldicarboxylic acid, 1,2-bis(phenoquine)ethane-4,4'-*carboxylic acid, alicyclic dicarboxylic acids such as hexahydroterephthalic acid, 4,4'-dihydroxo Other aromatic diols such as biphenylhydroquinone, chlorohydroquinone, meth-7-tylhydroquinone, phenylhydroquino7, and other aromatic oxocarboxylic acids such as m-oxybenzoic acid may be used in a manner that may impair the purpose of the present invention. )
Further copolymerization can be carried out in a small proportion to the extent that there is no problem.

The aromatic polyester of the present invention thus formed has a melting point of 40
It has extremely good melt fluidity at a low temperature of 0°C or less, and can be used for ordinary melt molding such as extrusion molding, injection molding, compression molding, and blow molding, and can be used for fibers, films, three-dimensional molded products, containers, hoses, etc. It is possible to process it into

During molding, the aromatic polyester of the present invention is
Reinforcing agents for glass fiber, carbon fiber, asbeth I, etc., fillers, nucleating agents, pigments, antioxidants, stabilizers, μ, plasticizers,
Additives such as lubricants, mold release agents, and flame retardants and other thermoplastic resins can be added to molded products to improve their properties.
Give tic ;”r>,s.

The molded article obtained from the novel aromatic polyester of the present invention has good optical anisotropy due to its parallel molecular alignment, and has extremely low mechanical properties.

The present invention will be further explained below with reference to Examples.

Example 1 p-ace1-quinobenzoic acid 3.24 y (1,8xl
O-2 mol), 2,7-diacedoquinaphthaleno 2.9
31 (1,2X 10-2 mol), 4,4'-diphenyldicarboxylic acid 2.90f (1,2X 10-2 mol)
was placed in a polymerization test tube, and acetic acid depolymerization was performed under the following conditions.

First, the reaction was carried out at 200 to 330°C for 21 hours in a nitrogen gas atmosphere, and then the pressure was reduced to 0.5% Hg at 330°C, and the polycondensation was completed by heating for an additional 0.75 hours.
98% of the theoretical amount of acetic acid (2.47 F) was distilled out to give a fibrillar, highly oriented, brown polymer.

The theoretical structural formula of this polymer is as follows, and the elemental analysis results of this polyester showed good agreement with the theoretical values as shown in Table 1. When the infrared absorption spectrum was measured, it was 1515.1585.1605.1725 z”-
It has a characteristic absorption.

[m/n=6/4 (molar ratio)] Table 1 When this polyester was placed on the sample stage of a polarizing microscope and the temperature was raised to check the melting point and optical anisotropy, it was found that the fluidity was good. It shows good optical anisotropy above ℃. The melt viscosity of this polyester is 320°C and the sliding speed is 3.
, 400 (1/sec) and showed good fluidity of 2,160 poise.

On the other hand, EKONOL E-2000 (manufactured by Sumima Kagaku Co., Ltd.), a commercially available p-oxybenzoic acid copolyester, has 41
0℃, sliding speed now 000 (1/sec) but fo, 0
The fluidity is extremely poor when the temperature exceeds 00 poise.

ma1ko2.7-diace1-quinnaphthalene instead of 2
．． Example 2 p-acetoquine benzoic acid (1), 2.7-'; acetoquine-naphthalene (1), 4,4'-diphenyldicarboxylic acid (I') ll, terephthalic acid (Iv) [Konouchi (■
)component,! = (I + lV) components are charged with the same number of moles] into a polymerization test tube, and a polycondensation reaction is carried out under the same conditions as in Example 1.

As shown in Table 2, all of the obtained polymers (Experiments 1 to 4) exhibited optical anisotropy and had extremely good fluidity.

As shown in Table 2, polymers other than the compositions of the present invention (Experiment N [15, 6) did not melt even at temperatures above 450° C. and had extremely poor fluidity.

Claims (1)

[Claims] River The following drawing unit (1), consisting of tUt and (ml, unit + 1) (1: 20 to 85 mol% of the whole, unit 1ll) + tll)
That's the whole thing. ~1.5 e k % 'a I/J Z
Ch'z"61' moldable copolymer polyester.