JPH0314863A - Thermotropic liquid crystal polyester composition - Google Patents

Abstract

PURPOSE:To prepare a thermotropic liquid crystal polyester compsn. excellent in the heat resistance represented by the hydrolysis resistance and long-term aging properties by compounding an org. epoxy compd. into a thermotropic liquid crystal polyester comprising specific structural units. CONSTITUTION:0.01-10 pts.wt. org. epoxy compd. is compounded into 100 pts.wt. thermotropic liquid crystal polyester which forms an anisotropic molten phase having a heat distortion temp. of 150 deg.C or higher and comprises structural units of formulas I to IV in molar ratios of (I+II)/(I+II+III), III/(I+II+III), and I/II of 0.750.95, 0.25-0.05, and 75/25-95/5 respectively, wherein R1 is formula V; and R2 is formula VI. The org. epoxy compd. is not particularly limited.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a thermotropic liquid crystal polyester composite having extremely high hydrolysis resistance and heat resistance represented by long-term aging characteristics.

In recent years, the demand for higher performance plastics has been increasing, and many polymers with various new performances have been developed. Among them, optically anisotropic liquid crystal polymers have excellent chemical resistance and mechanical As the above-mentioned liquid crystal polymer, for example, a liquid crystal polymer obtained by copolymerizing polyethylene terephthalate with p-hydroxybenzoic acid is known. (Japanese Unexamined Patent Publication No. 49-72393).

<Problems to be Solved by the Invention> However, since the above-mentioned liquid crystal bolimar has a low glass transition temperature, its stability against water, that is, its hydrolysis resistance or long-term aging properties, is not necessarily sufficient.
There were problems with practicality.

It is an object of the present invention to solve the above-mentioned problems and to obtain a thermotropic liquid crystalline polyester composition having excellent heat resistance represented by hydrolysis resistance and long-term aging properties.

Means for Solving the Problems> Therefore, as a result of intensive studies to achieve the above problems, the present inventors found that only when an organic epoxy compound was added to a thermotropic liquid crystal polyester consisting of a specific structural unit, reached the light of day.

That is, the present invention consists of the following structural units (I) to (IV), and the structural unit [ (Eng) + (II)] is [ (I
75 to 95 mol% of > + (II> + (III) ], the structural unit (I [I) is [ (I) + (II>+
(■)], and the structural unit (I>/(
II> molar ratio of 7 5/2 5 to 95/5 and a heat deformation temperature of 150° C. or higher to form an anisotropic melt phase. The present invention provides a thermotropic liquid crystalline polyester composition containing 0.0 to 10 parts by weight of the compound.

CH, +0-Rl -0+- ÷O-CH2CH2 -0+- +OC-R2-CO+- ...(II) ...(I[I) ...(IV) Indicates one or more groups . However, in the formula, X represents a hydrogen atom or a chlorine atom. 〉 The thermotropic liquid crystal polyester used in the present invention is a structural unit of a polyester in which the above structural unit (I> is derived from p-hydroxybenzoic acid, and the structural unit (II
) is 4,4°-dihydroxybiphenyl, hydroquinone, 2,6-dihydroxynaphthalene, t-butylhydroquinone, 3.3-,5.5-tetramethyl-4.
It is a structural unit produced from an aromatic diol selected from 1-dihydroxybiphenyl, phenylhydroquinone, and bisphenol A, and further contains a structural unit (II[
) is a structural unit derived from ethylene glycol,
Structural unit (IV) is terephthalic acid, 4.4″-diphenyldicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 4
．． 4-1 diphenyl ether dicarboxylic acid, 1.2-bis(phenoxy)ethane-4.4-1 dicarboxylic acid, 1
．． 2-bis(2-chlorophenoxy)ethane-4.4'
- While the structural units [ (I) + (II)] of the above structural units (I) to (IV) are [ (I>+ (II)
+ (III)] is 77 to 95 mol%, preferably 80 to 93 mol%.

Moreover, the structural unit (III) is [(I>+(It)+(II
I)] 23 to 5 mol%, preferably 20 to 18
It is mole%. The structural unit [(H+(■〉)] is [ (I>
+ DI>+ (III> ) If it is greater than 95 mol %, the melt fluidity will decrease and it will solidify during polymerization, and if it is less than 77 mol %, the heat resistance will be poor, which is not preferable. > molar ratio is 7 5/2 5~95/
5, preferably 78/22 to 93/7.

If the groove is not 75/25 or is larger than 95/5, the heat resistance will be poor and the fluidity will be poor, making it impossible to achieve the object of the present invention.

Typical methods for producing the copolymerized polyester used in the present invention include the following method.

(1) Acylated products of hydroxybenzoic acid such as p-acetoxybenzoic acid, diacylated products of aromatic dihydroxy compounds such as 4,4゛-diacetoxybiphenyl, aromatic dicarboxylic acids such as terephthalic acid, and ethylene such as polyethylene terephthalate. A method for producing polyester from glycol and aromatic dicarboxylic acid by deacetic acid polymerization.

(2> From aromatic dihydroxy compounds such as p-hydroxybenzoic acid, 4.4-1-dihydroxybiphenyl, aromatic dicarboxylic acids such as acetic anhydride and terephthalic acid, and ethylene glycol and aromatic dicarboxylic acids such as polyethylene terephthalate) A method for producing polyester by deacetic acid polymerization.

Although these polycondensation reactions proceed without a catalyst, it is sometimes preferable to add metal compounds such as stannous acetate, tetrabutyl titanate, sodium and potassium acetate, antimony trioxide, and metallic magnesium.

Further, the melt viscosity of the copolymerized polyester used in the present invention is 1
0 to 15,000 boise is preferred, especially 20 to 5,0
00 poise is more preferable.

Note that this melt viscosity is a value measured using a Koka type flow tester under conditions of (liquid crystal starting temperature + 40° C.) and a slip rate of 1.000 (1/sec).

On the other hand, the logarithmic viscosity of this copolymerized polyester is 0.1 g/
The dN concentration, measured in pentafluorophenol at 60°C, is preferably 0.5 to 5 cNl/g, preferably 1.0 to 3. Particularly preferred is Od j /g.

In addition, when polycondensing the copolymerized polyester used in the present invention, in addition to the above-mentioned structural units (I) to (IV), isophthalic acid, 3,3-diphenyldicarboxylic acid, 2.2 11 Aromatic dicarboxylic acids such as diphenyldicarboxylic acid, aliphatic dicarboxylic acids such as adipic acid, azelaic acid, sebacic acid, dodecanedioic acid, alicyclic dicarboxylic acids such as hexahydroterephthalic acid, chlorohydroquinone, methylhydroquinone, 4 .4-1 dihydroxydiphenyl sulfone, 4.4-1 dihydroxydiphenylpropane, 4,4-1 dihydroxydiphenyl sulfide, 4,4-dihydroxybenzophenone,
Aromatic diols such as 4.4'-dihydroxydiphenyl ether, fats such as 1.4-butanediol, 1.6-hexanediol, neopentyl glycol, 1.4-cyclohexanediol, 1.4-cyclohexanedimethanol, etc. It is possible to further copolymerize a small amount of a group, alicyclic diol, and an aromatic hydroxycarboxylic acid such as m-hydroxybenzoic acid and 2,6-hydroxynaphthoic acid without impairing the purpose of the present invention. .

Organic epoxy compounds used in the present invention are not necessarily limited to glycidyl ethers synthesized from phenols and shrimp chlorohydrin, such as bisphenol A diglycidyl ether, ortho-phenylphenol glycidyl ether, and hexahydrophthal acid diglycidyl ester, tetrahydrophthalic acid diglycidyl ester, terephthalic acid diglycidyl ester,
Glycidyl esters such as isophthalic acid diglycidyl ester and glycidyl methacrylate, glycidyl esters and ethers consisting of hydroxycarboxylic acids and shrimp chlorohydrin such as glycidyl esters and ethers of p-hydroxybenzoic acid, and epoxidized imides such as N-glycidyl phthalimide. compound, an epoxy group-containing copolymer consisting of an unsaturated monomer having an epoxy group such as epoxidized polybutadiene and glycidyl methacrylate and another unsaturated monomer such as ethylene, or γ-glycidoxypyltrimethoxysilane Epoxy silanes, which are commonly used as silane coupling agents, are included.

Among the above organic epoxy compounds, preferred specific examples of glycidyl ethers include orthophylphenol glycidyl ether and bisphenol A type epoxy compounds represented by the following structural formula (V).

Preferred specific examples of glycidyl esters include hexahydrophthalic acid diglycidyl ester and tetrahydrophthalic acid glycidyl ester.

Preferred specific examples of glycidyl ether/esters include epoxy compounds of the following structural formula (Vl).

The value of the degree of polymerization n of the compound of formula (V) is O or an integer of 1 to 20, preferably 0 or an integer of 1 to 10, and may be a mixture of compounds having various degrees of polymerization.

In the group group or alicyclic group, n represents 0 or an integer of 1 to 20. ) Specific examples of Ar include 1.4-phinylene, 1.3-
Phenylene, 1,2-phenylene, 2-methyl-{,4
-phenylene, 4,4-biphenylene, 3.3"-biphenylene, 2.2-biphenylene, 3,4"-biphenylene, 1.4-naphthylene, 1.5-naphthylene, 2
, 6-naphthylene, 2,7-naphthylene, 1.4-cyclohexylene, 1.3-cyclohexylene, 1,2-cyclohexylene, 4.4゛-bicyclohexylene, 2,
Preferred examples include 6-decahydronaphthylene, among which 1,4-phenylene, 1,3-phenylene and 2
, 6-naphthylene is particularly preferred.

It is particularly preferable that the average degree of polymerization (II) is in the range of 0 to 5, and the ratio of weight average molecular weight (Mw) to number average molecular weight (Mn), Mw/Mn, is in the range of 1.0 to 3.0. It is something. The method for producing the epoxy compound represented by the formula (Vl) is not particularly limited, but for example, a hydroxycarboxylic acid and an epihalohydrin are mixed in the presence of a catalyst such as a quaternary ammonium salt, a tertiary amine, or a tertiary phosphine. Examples include a method of producing by reacting at 40 to 150° C. to perform halohydrin ester etherification, and then adding an alkali metal salt to dehydrohalogenate. A product with a high degree of polymerization can be obtained by further reacting a hydroxycarboxylic acid in the presence of a catalyst in different ratios.

Further, as preferred specific examples of the epoxy group-containing copolymer, ethylene/glycidyl methacrylate copolymer and ethylene/glycidyl methacrylate/vinyl acetate copolymer containing 1 to 30% by weight of glycidyl methacrylate are preferred.

Preferred specific examples of epoxysilanes include γ-glycidoxybrobyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, 2-(3,4-
Examples include epoxycyclohexyl>ethyltrimethoxysilane.

Particularly preferred epoxy compounds among the above are bisphenol A type epoxy compounds represented by the above structural formula (V), glycidyl ether esters and epoxy silanes shown by the above structural formula (Vl).

The epoxy equivalent of the organic epoxy compound in the present invention is {
00 to 3,000 is preferable. The epoxy equivalent herein refers to the Durham number of a compound containing 1 g equivalent of epoxy groups.

The amount of the organic epoxy compound added in the present invention is 0.00 parts by weight per 100 parts by weight of the thermotropic liquid crystal polyester.
0} to 10 parts by weight, preferably 0.05 to 5 parts by weight, more preferably 0.2 to 3 parts by weight. Added amount is 0
．． If the amount is less than 1 part by weight, the effect of improving the hydrolysis resistance of the thermotropic liquid crystal polyester will not be sufficient;
If the amount exceeds 0 parts by weight, the mechanical properties of the thermotropic liquid crystal polyester resin will be impaired, which is not preferable.

The thermotropic liquid crystal polyester injection molded product of the present invention is made of the thermotropic liquid crystal polyester detailed above, and the cylinder temperature is usually above the liquid crystal starting temperature and below 330°C, preferably above (liquid crystal starting temperature 10°C) and below 320°C.
Hereinafter, it is obtained by injection molding into a three-dimensional or shaped product under the condition that the mold temperature is 10° C. or higher and 150° C. or lower, preferably 30° C. or higher and 120° C. or lower.

The thermotopic liquid crystal polyester injection molded product of the present invention contains reinforcing materials such as glass fiber, carbon fiber, and asbestos, fillers, nucleating agents, pigments, antioxidants, stabilizers, plasticizers, lubricants, mold release agents, and Additives such as fuel agents and other thermoplastics can be added to impart desired properties.

The heat distortion temperature of the injection molded product of the present invention (load 18.6 kg
/csA) is a value measured according to ASTM D648, and must be 150℃ or higher, and 'L
The temperature is preferably 80°C or higher.

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

Reference Example 1 466 parts by weight of p-hydroxybenzoic acid, 84 parts by weight of 4.4'-dihydroxybiphenyl, anhydrous vinegar'fIi480
parts by weight, 75 parts by weight of terephthalic acid and an intrinsic viscosity of about 0.
．． 130 parts by weight of polyethylene terephthalate of 6 dβ/g was charged into a reaction vessel equipped with a stirring blade and a distillation tube, and acetic acid depolymerization was carried out under the following conditions.

First, under a nitrogen gas atmosphere at 100 to 250°C for 5 hours,
After reacting at 250 to 300°C for 1.5 hours, 300°C
℃, reduced pressure to 0.3+nmHQ for 1 hour, and further heated to 3.7
When the reaction was allowed to proceed for 5 hours and the polycondensation was completed, approximately the theoretical amount of acetic acid was distilled out, and a resin having the following theoretical structural formula was obtained.

-{-OCH2CH20→1m kzQ /m/n=75/1 0/1 5/2 5 Also, this polyester was placed on the sample stage of a polarizing microscope and the temperature was raised to confirm the optical anisotropy. As a result, the liquid crystal initiation temperature was 272°C, and good optical anisotropy was exhibited. The logarithmic viscosity of this polyester (measured at 60°C in pentafluorophenol at a concentration of 0.1 g/d.f.) is 1.88 d.
．． Q/g, and the melt viscosity at 312° C. and a shear rate of 1,000/sec was 2900 poise.

In addition, the heat distortion temperature was 208°C (measurement method will be described later)
.

Reference Example 2 72.58 parts by weight of p-acetoxybenzoic acid and an intrinsic viscosity of about 0.6 d. 51.61 parts by weight of G/r polyethylene terephthalate was charged into a reaction vessel equipped with a stirring blade and a distillation tube, and reacted in a nitrogen gas atmosphere at 200 to 250°C for 5 hours and at 250 to 280°C for 2 hours. , 280℃
When the pressure was reduced to 0.6 nvnH (l) for 1 hour and the reaction was further allowed to proceed for 2 hours, approximately the theoretical amount of acetic acid was distilled out, and a resin having the following theoretical structural formula was obtained.

÷OCH, CH20→1/m M /m/n=60/40/40 Also, place this polyester on the sample stage of a polarizing microscope,
As a result of observing the optical anisotropy at elevated temperature, the liquid crystal initiation temperature was 240° C., indicating good optical anisotropy. The logarithmic viscosity (measured under the same conditions as Reference Example 1) of this polyester was 0.71 dN/g, and the melt viscosity at 280°C and a shear rate of 1,000/sec was 810 voids. The deformation temperature was 64°C (the measurement method will be described later).

Examples 1-7. Comparative Examples 1 to 4 Thermotobic liquid crystal polyester 10 of Reference Examples 1 and 2
For 0 parts, the following organic epoxy compounds (A) to (F
) were dry blended in the proportions listed in Table I, then 30nw
Using a φ twin-screw extruder, the mixture was melt-kneaded at 270 to 300°C and then pelletized.

The pellets were subjected to a Sumitomo Necool injection molding machine Promat 40/25 (manufactured by Sumitomo Heavy Industries, Ltd.) at a cylinder temperature of 270 to 300°C and a mold temperature of 40 to 90°C.
/ 8" thick ASTM Nα1 dumbbell and 1/8"
A Xi/2" x 5" test bead was molded.

The obtained ASTMI dumbbell was placed in a 3 fI pressure container containing ion exchange water. This pressure-resistant container was placed in a gear oven maintained at 80° C., and a hydrolysis resistance test was conducted for 60 days. Further, an ASTM No. 1 dumbbell was placed in a gear oven maintained at 190° C., and a dry heat deterioration test was conducted for 60 days.

The heat distortion temperature was measured using a heat distortion temperature measurement device manufactured by Toyo Seiki.
1 8. 6 kg/oi) was measured.

The above results are also shown in Table 1.

[Additive list F: CHx CH CH2 0 (CH2)
s St (OCHx )i\0/ As is clear from the results in Table 1, when an organic epoxy compound is added to a specific thermotropic liquid crystal polyester, heat resistance, typified by hydrolysis resistance and long-term aging properties, is improved. A thermotropic liquid-crystalline polyester composition is obtained.

On the other hand, when no organic epoxy compound was added (Comparative Example 1) or when the amount of the organic epoxy compound of the present invention added was small (Comparative Example 2), mechanical properties decreased during hot water treatment and long-term aging. is large.

Furthermore, when thermotopic liquid crystal polyesters other than those of the present invention are used (Comparative Examples 3 and 4), even if an organic epoxy compound is added, the effect of improving hydrolysis resistance and long-term aging properties is small.

Examples 8 to 13, Comparative Examples 5 to 8 Thermotobic liquid crystal polyester 10 of Reference Examples 1 and 2
0 parts, glass fiber (3 mm long chopped strand type) 25 parts, organic boxy compound (A) to (F
) were dry blended in the proportions listed in Table 2, then 30
The mixture was melt-kneaded at 270 to 300°C using a twin-screw extruder and then pelletized.

This pellet was subjected to a Sumitomo Necool injection molding machine, Promat 40/25 (manufactured by Sumitomo Heavy Industries, Ltd.), and a cylinder temperature of 270 to 300°C and a mold temperature of 40 to 90°C were used to make a 1/8” thick ASTM Nα1 dumbbell and 1/8” x
A 1/2" x 5" test piece was prepared. Using the obtained test beads, physical properties were evaluated under the same conditions as in Example 1.

The results in Table 2 show that even when glass fiber is added, the composition of the present invention provides a thermotropic liquid crystal polyester composition with excellent hydrolysis resistance and long-term aging properties.

<Effects of the Invention> The thermotropic liquid crystal polyester composition of the present invention has the following properties:
It has excellent heat resistance, typified by hydrolysis resistance and long-term aging properties, and is useful for applications such as mechanical parts, automobile parts, and sealing materials that are exposed to high temperature, high humidity, or high temperature conditions.

Claims (1)

[Claims] Consisting of the following structural units (I) to (IV), the structural unit [(
I) + (II)] is 7 of [(I) + (II) + (III)]
5 to 95 mol%, the structural unit (III) is [(I) + (II)
+ (III)], and the structural unit (I)
/(III) in a molar ratio of 75/25 to 95/5 and a heat distortion temperature of 150°C or higher. A thermotropic liquid crystal polyester composition containing 0.01 to 10 parts by weight. ▲There are mathematical formulas, chemical formulas, tables, etc.▼...(I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼...(II) ▲There are mathematical formulas, chemical formulas, tables, etc.▼...(III) ▲Mathematical formulas , chemical formulas, tables, etc. ▼...(IV) (However, R_1 in the formula is ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ Mathematical formulas, chemical formulas,
There are tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ Mathematical formulas, chemical formulas,
There are tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ R_2 is ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲
There are mathematical formulas, chemical formulas, tables, etc. ▼▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ One or more groups selected from show. However, in the formula, X represents a hydrogen atom or a chlorine atom. )