JPS60188423A - Aromatic polyester - Google Patents

Abstract

PURPOSE:An aromatic polyester having melt moldability and an excellent balance between optical anisotropy and mechanical property, containing 2,7-dihydroxynaphthalene. CONSTITUTION:A mixture of p-acetoxybenzoic acid, a dihydroxynaphthalene diester such as dihydroxynaphthalene diacetate or dipropionate and 1,2-bis (phenoxy)ethane-4,4'-dicarboxylic acid or 1,2-bis(2-halophenoxy)ethane-4,4'-dicarboxylic acid is polycondensed by elimination of a monocarboxylic acid to obtain an aromatic polyester comprising structural units of formulas I -III (wherein the dioxynaphthalene include 2,7- and 2,6-dioxynaphthalenes and X is Cl or Br). In said aromatic polyester, units I amount to 0-85mol%, units II+III amount to 100-15mol%, the molar ratio of 2,7-dioxynaphthalene to 2,6-dioxynaphthalene in each of units II and III is 100/0-40/60, and the molar ratio, unit II/unit III, is 100/0-40/60.

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. The liquid crystal polymer is excellent.
It is attracting attention because of its co-mechanical properties.

Fully aromatic polyesters are widely known as such liquid crystal polymers, and for example, homopolymers and copolymers of p-hydroxybenzoic acid are commercially available under the trademark -EKONOL'. However, these p-hydroxybenzoic acid homopolymers and copolymers have too high a melting point to be melt moldable, and have high melt viscosity and poor moldability. Therefore, a method of copolymerizing p-hydroxybenzoic acid with various components to lower its melting point was discovered. A method of copolymerizing long carboxylic acids (Published Patent Publication No. 55-500215), a method of copolymerizing p-hydroxybenzoic acid with 2,6-dihydroxynaphthaleno and terephthalic acid (Japanese Unexamined Patent Publication No. 54-50594)
Although the melting point of p-hydroxybenzoic P and 2,6-hydroxyanthraquinone ter is relatively low at 400°C or lower, the fluidity of the polymer is insufficient, and even better fluidity is desired. It is rare.

Therefore, the present inventors conducted intensive studies with the aim of obtaining an aromatic polyester that is melt moldable and has a well-balanced optical anisotropy and mechanical properties represented by a high modulus of elasticity.1 As a result, p
-hydroxybenzoic acid, 2,7-dihydroxynaphthaleno, 2,6-'; hydroxynaphthalene, 1,2-his(phenoquine)ethane-4I47-dicarboxylic acid, 1,
2-His(2-chlorphenoquine)ethane-4,4'-
It has been discovered that an aromatic polyester having a specific structure consisting of carboxylic acid and 1,2-bis(2-jromphenoxy)ethane-4,c-*carboxylic acid satisfies the above objectives, and has accomplished the present invention. One step to reach this point.

That is, the present invention consists of the following structural units (1), tU) and tl), the unit f11 occupies 0 to 85 mol% of the whole, the unit till + [11) occupies 100 to 15 mol% of the whole, and the unit (It ), the molar ratio of 2,7-dioxynaphthalene and 2,6-dioxynaphthalene in (II) is 10010 to 40/60, and the unit (1) / fl
The present invention provides a melt-moldable aromatic polyester characterized in that the molar ratio of + is 10,010 to 40/60.

3- (However, the unit is tll), dioxynaphthalene in (1) is 2,7- and / is 2,6-dioxynaphthalene, and X is a chlorine atom or a bromine atom)
In the aromatic polyester of the present invention, the structural unit t
++ represents the structural unit of t-copolyester produced from p-hydroxybenzoic acid, and the structural unit tlll represents dihydroquinaphthalene and 1,2-bis(phenoxy)ethane-4.
, 4'-dicarboxylic acid, and one polyester structural unit (tl) is formed from dihydroxynaphthaleno and 1,2-bis(2-chlorophenoxy)ethano-4,4'-dicarboxylic acid. or 1゜2-bis (2
-bromophenoquine)ethane-4,4' = one structural unit of polyester produced from dicarboxylic acid.

= 41 The aromatic polyester of the present invention has a melting point of 400°C or less, and can be easily molded into fibers, films, various molded products, etc. with poor mechanical properties by ordinary melt molding. .

Since the polyarylate containing 2,7-dihydroxynaphthaleno of the present invention does not have very good symmetry, it is extremely unique that it becomes an optically anisotropic polyester with good fluidity.
, 16t7) 1032 (' 831 includes W,
[2I7] by Jerome Jackson, Jr.
- Polyarylate consisting of dihydroxynaphthalene and terephthalic acid clearly does not form liquid crystals.'' Therefore, the present invention is completely unexpected from conventional knowledge.

In the aromatic polyester of the present invention, the structural unit t
The proportion of 1+ is 0 to 85 mol% of the total, especially 0 to 85 mol%
The amount is preferably 80 mol %, and if it exceeds 85 mol %, the melting point of the aromatic polyester is high, resulting in poor melt fluidity and poor mechanical properties, which is not preferred.

The molar ratio of 2,7-oxynaphthalene and 2.6-oxynaphthalene is 10010 to 40/60, preferably 10
010-50150. If the molar ratio is smaller than 40/60, the melt fluidity will be poor, which is not preferable. Also,
The molar ratio of unit 1ll) / +I'll is 10010 ~
40/60, preferably 10010 to 50150
It is. If the molar ratio is less than 40/60, it becomes isotropic, resulting in poor optical anisotropy and high melt viscosity, which is not preferable.

The aromatic polyester of the present invention has a melt viscosity of 50 to 10.
It is preferable that it is 000 poise, and the Rio value is 100
~5. Those with OOO poise are preferred.

What is melt viscosity here (liquid crystal start temperature → -40 to 80℃)
These values were measured using a Koka type flow tester at a temperature of 2,000 to 4,000 (1/sec) at a sliding speed of 2,000 to 4,000 (1/sec).

That is, if the melt viscosity is lower than 50 poise, the strength of the obtained molded product will be low, and if it is higher than 10,000 poise, the moldability will be poor and the mechanical properties of the obtained molded product will also tend to be poor.

The aromatic polyester of the present invention can be produced according to the conventional polyester disarmament 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 p-acetoquinebenzoic acid and dihydroxynaphthalene such as diacete-1-, dipropione-1, and 1,2-bis(phenoquine)ethane-4+4'-dicarboxylic acid, 1,2-
Bis(2-halogenated phenoxy)ethane-4,4'-
Demonolysis from dicarboxylic acid (blank below on this page) 7-Production method by carboxylic acid polycondensation reaction (2) Phenyl ester of dihydroxynaphthalene and p-oxybenzoic acid, 1,2-bis(phenoquine)ethane-4,4
'-Dicarboxylic acid, 1,Production method by dephenol polycondensation from diphenyl ester of 2-bis(2-halogenated phenoxy)ethane-4,4'-dicarboxylic acid (3) p-oxybenzoic acid, 1, 2-bis(phenoxy)efnor 4,4'-dicarboxylic acid, 1,2-bis(2
- A method in which a desired amount of diphenyl carbonate is reacted with halokenated phenoquino)ethane-4,4'-dicarboxylic acid to form each diphenyl ester, and then dihydroquinaphthalene is added to produce a phenol-free polycondensation reaction. Used in polycondensation reaction. As a catalyst, stannous acetate, TeI
Metal compounds such as butyl titanate 1-1 sodium acetate and antimony trioxide are representative, and are particularly effective in dephenol polycondensation.

In addition, when polycondensing the aromatic polyester of the present invention,
In addition to the 8- components that depict the above structural unit +11, (Ill and (■)), terephthalic acid, isophthalic acid, 4.4'-
diphenyldicarboxylic acid, 3.3'-diphenyldicarboxylic acid, 3.4'-diphenyldicarboxylic acid, 2.2'
- aromatic dicarboxylic acids such as diphenyldicarboxylic acid,
cycloaliphatic dicarboxylic acids such as hexahydroterephthalic acid,
4.4'-dihydroxybiphenyl, hydroquinone,
Other aromatic diols such as chlorohydroquinone, methylhydroquinone, phenylhydroquinone and m-
Other aromatic oxocarboxylic acids such as oxybenzoic acid can be further copolymerized within a small proportion that does not impair the object of the present invention.

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

Note that during molding, desired properties such as glass fiber, carbon fiber, asbestos, etc. can be imparted to the aromatic polyester of the present invention.

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

Example 1 2,7-dihydroquine naphthalene diacetate 4,8
81 (2X10-2 mol), 6.04y (2
x10-2 mol) into a polymerization test tube, and acetic acid depolymerization was carried out under the following conditions.

First, the reaction was carried out at 240 to 290°C for 23 hours in a nitrogen gas atmosphere, and then the pressure was reduced to 0.6% Hg at 290°C, and the polycondensation was completed by heating for an additional hour, resulting in 98% of the theoretical amount. 2.41% of acetic acid was distilled out to give a fibrillar, highly oriented, dark brown polymer.

The theoretical structural formula of this polymer is as follows, and the elemental analysis results of the polyester are in good agreement with the theoretical values as shown in Table 1. Measure the infrared absorption spectrum and
Kokoro 1515.1585.1605.1725 f
It has a characteristic absorption at f1-1.

Table 1 This polyester was placed on the sample stage of a polarizing microscope and heated to confirm its melting point and optical anisotropy. It showed good fluidity and good optical anisotropy at 211-247°C. Ko.

The melt viscosity of this polyester is 280°C, the sliding speed is 3,
It showed good 11-fluidity of 760 polys at 900 (1/sec).

On the other hand, EKONOL E-2000 (manufactured by Sumima Kagaku Co., Ltd.), a commercially available p-oxybenzoic acid copolyester, has 41
Even at 0℃ and sliding speed of 4,000 (1/sec), t, o, 0
00 Poise XL has extremely poor fluidity.

Also, instead of 2,7-diacetquinaphthalene, 2,6
The following polyarylate using acetoquinone had extremely poor fluidity even when the liquid crystal started at 378°C and at 400°C or higher.

Example 2 p-acetoquinbenzoic acid (1L2.7-diacetoquinaphthalene (It), 2.6-diacetoquinaphthalene (ml, 1,2-bis(phenoxy)ethane-4,4')
-dicarboxylic acid α), I+2-bis(2-chlorophenoquino)ethane-4,4′-dicarboxylic acid (Vl and l
, 2-bis(2-bromphenoxy)ethane-4,4'
-Dicarboxylic acid (■) [of which the (ll+1Il) component and the ([+12-V+■) component are charged in the same number of moles] was charged into a polymerization test tube, and a polycondensation reaction was carried out under the same conditions as in Example 1. I did this.

The obtained polymers (Experiments N [11 to 8) all exhibited optical anisotropy as shown in Table 2 and had extremely good fluidity.

In addition, comparative examples other than the composition of the present invention (experimental points 9 to 14)
As shown in Table 2, it does not flow even at temperatures above 500°C and becomes isotropic, resulting in poor fluidity.

Claims (1)

[Claims] Consisting of the following structural units ill, +111 and fllll, unit (1) is θ~85 moa 1/% of the whole, 14
tl) -1-1ll) is the total 1o. ~15 mol%, 2 in units (Ill, tl)
, the molar ratio of 7-dioxynaphthalene and 2,6-dioxynaphthalene is 10010 to 40/60, and the unit (I
)/(Ill) nomolar ratio is 10010 to 4o/6o. (However, dioxynaphthalene in the units (Ill, 1ll) indicates 2.7- and/or 2.6-dioxynaphthalene, and X indicates a chlorine atom or a bromine atom)