JP2611376B2 - Liquid crystal polyester resin composition - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a liquid crystal polyester resin composition having excellent heat resistance, fluidity and rigidity.

[Conventional technology]

In recent years, there has been an increasing demand for higher performance plastics, and a number of polymers having various new properties have been developed and marketed. Among them, the optical anisotropy is characterized by a parallel arrangement of molecular chains. Liquid crystal polymers are noted for having excellent mechanical properties.

Examples of the polymer forming the anisotropic molten phase include p-
Liquid crystal polymer obtained by copolymerizing hydroxybenzoic acid with polyethylene terephthalate (JP-A-49-72393), p-
A liquid crystal polymer obtained by copolymerizing hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid (JP-A-54-77691);
Also, a liquid crystal polymer obtained by copolymerizing p-hydroxybenzoic acid with 4,4'-dihydroxybiphenyl, terephthalic acid and isophthalic acid (Japanese Patent Publication No. 57-24407) is known.

As a liquid crystal polyester resin composition, a composition comprising a liquid crystal polyester containing a naphthalene moiety and a liquid crystal polyester derived from 1,2-bis (phenoxy) ethane-4,4'-dicarboxylic acid is known. (JP-A-57-40550).

On the other hand, thermoplastic resins other than liquid crystal polymers are generally inferior in fluidity and rigidity to liquid crystal polymers.

In order to improve this, it has been proposed to add a liquid crystal polymer to a thermoplastic resin to form a composition (Japanese Patent Laid-Open No. 56-11 / 1981).
No. 5357, JP-A-57-51739, etc.).

[Problems to be solved by the invention]

However, Japanese Patent Application Laid-Open Nos.
No. 4-77691, the liquid crystal polymer described in JP-B-57-24407 and the completely aromatic polyester used in the composition described in JP-A-57-51739 have a heat distortion temperature of 190 ° C. The heat resistance is insufficient and the heat distortion temperature is 190 ° C or higher and the heat resistance is good, but the liquid crystal starting temperature is too high and molding is not possible unless the temperature is 400 ° C or higher, and the melt viscosity is high. However, they do not have a balance between heat resistance, moldability, and fluidity, and are required to further improve rigidity. Further, it has been pointed out that the surface of the molded product is peeled off by friction.

The composition composed of a double liquid crystal polyester having a specific structure known in JP-A-57-40550 has insufficient rigidity yet, and when blended with a thermoplastic resin, the composition with the thermoplastic resin has Due to poor affinity, the effect of improving the properties of the thermoplastic resin was also insufficient.

Further, JP-A-56-115357 and JP-A-57-5173.
The liquid crystal polymer known in Japanese Patent Publication No. 9 and the like has a problem that compatibility with a thermoplastic resin is low, and strength is greatly reduced.

An object of the present invention is to solve the above-mentioned problems and to obtain a liquid crystal polyester resin composition excellent in heat resistance, fluidity, rigidity, mechanical properties, and peel resistance.

[Means for solving the problem]

The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have reached the present invention.

That is, the present invention provides the following structural units (I), (II),
Heat deformation temperature consisting of (III) and (IV) is 190-280 ° C
Of the liquid crystal polyester (A) of 99-1% by weight and the following structural unit (I ′) or [(I ′), (II ′) and (II)
I ′)], a liquid crystal polyester resin composition comprising 1 to 99% by weight of a liquid crystal polyester (B) having a heat distortion temperature lower than 190 ° C. (However, X in the formula is Represents one or more groups selected from —CH ₂ CH ₂ —, wherein the carbonyl groups of the structural unit (IV) are in a para- and / or meta-position with each other, and 50 mol% or more of them are in the para-position. The structural units [(II) + (III)] and (IV) are substantially equimolar. ) OY'-O ... (II ') (Where X 'in the formula is Y ' And at least one group selected from —CH ₂ CH ₂ —, wherein the carbonyl groups of the structural unit (III ′) are para and / or
Or they are in a meta position. The structural units (II ') and (III') are substantially equimolar. And a liquid crystal polyester resin composition comprising 99 to 1% by weight of the liquid crystal polyester resin composition and 1 to 99% by weight of another thermoplastic resin (C).

The liquid crystal polyester (A) in the present invention is a copolymer comprising the structural units (I), (II), (III) and (IV).

The structural units (I), (II), (III) and (IV)
Is arbitrary, but the following copolymerization amount is preferred from the viewpoint of fluidity. That is, the structural unit (I)
Is preferably from 40 to 90 mol% of [(I) + (II) + (III)], and particularly preferably from 60 to 80 mol%. The structural unit (II) / (III) has a molar ratio of 9/1.
To 1/9 is preferable, and in the structural unit (III), -X-
There -CH ₂ CH ₂ - otherwise preferably 7.5 / 2.5 to 2.5 / 7.5, particularly preferably 7.5 / 2.5 to 4/6.

Among them, [(I) + (II) + (II)
The copolymerization ratio with respect to [(I) + (II) + (III)] of (II) is 72-78 mol% with respect to [I]).
1515 mol%, the copolymerization ratio of (III) to [(I) + (II) + (III)] is 10-20 mol%, and -X- is 70 mol%
Or -CH ₂ CH ₂ - and most preferably.

The heat distortion temperature of the liquid crystal polyester (A) in the present invention is from 190 to 280 ° C, preferably from 190 to 260 ° C, particularly preferably from 190 to 220 ° C, from the balance between heat resistance and fluidity. Here, the heat distortion temperature is a value obtained by measuring a 1/8 ″ thick test piece at a stress of 18.6 kg / cm ² based on the ASTM D648 standard.

The liquid crystal onset temperature of the liquid crystal polyester (A) in the present invention is not particularly limited, but is determined from the balance between heat resistance and fluidity.
250-320 ° C is preferred, and 260-280 ° C is particularly preferred.

The melt viscosity of the liquid crystal polyester (A) in the present invention is not particularly limited, but is preferably 10,000 poise or less, particularly preferably 5,000 poise or less in terms of moldability and fluidity.
Most preferred is 3,000 poise or less.

The melt viscosity is a value measured by a Koka type flow tester under the condition of (liquid crystal onset temperature + 40 ° C.) and a shear rate of 1,000 (1 / second).

The method for producing the liquid crystal polyester (A) comprising the structural unit is not particularly limited, and can be produced according to a known polyester polycondensation method.

For example, in the structural unit (III), -X- is -CH ₂ CH
_In cases other than _{2-, the following} (1) to (4), -X- is -CH ₂ CH
_In the case of _2-, the production method (5) is preferably mentioned.

(1) A method of producing from a diacylated aromatic dihydroxy compound such as p-acetoxybenzoic acid, 4,4'-diacetoxybiphenyl, paraacetoxybenzene and an aromatic dicarboxylic acid such as terephthalic acid by a deacetic acid polycondensation reaction.

(2) After reacting acetic anhydride with an aromatic dihydroxy compound such as p-hydroxybenzoic acid, 4,4'-dihydroxybiphenyl, or hydroquinone, or an aromatic dicarboxylic acid such as terephthalic acid to acylate a phenolic hydroxyl group, A method of producing by a deacetic acid polycondensation reaction.

(3) phenyl ester of p-hydroxybenzoic acid,
A method of producing from an aromatic dihydroxy compound such as 4,4'-dihydroxybiphenyl or hydroquinone and a diphenyl ester of an aromatic dicarboxylic acid such as terephthalic acid by a phenol removal polycondensation reaction.

(4) A desired amount of diphenyl carbonate is reacted with an aromatic dicarboxylic acid such as p-hydroxybenzoic acid and terephthalic acid to form a diphenyl ester, and then an aromatic dihydroxy compound such as 4,4'-dihydroxybiphenyl and hydroquinone is prepared. In addition, a method of producing by a dephenol polycondensation reaction.

(5) In the presence of polyethylene terephthalate (1)
Or a method of manufacturing by the method of (2).

Since a liquid crystal polyester (A) having a high degree of polymerization can be obtained,
It is more preferable to use the method (2).

Typical catalysts used in the polycondensation reaction include metal compounds such as stannous acetate, tetrabutyl titanate, potassium acetate, antimony trioxide, magnesium, sodium acetate, and zinc acetate. It is effective for

Some liquid crystal polyesters (A) comprising the above structural units can be measured for intrinsic viscosity in pentafluorophenol, and in that case, 0.5 dl is measured at a concentration of 0.1 g / dl at 60 ° C. / g or more is preferable, especially 1.0 to 15.0 dl
/ g is preferred.

The liquid crystal polyester (A) comprising the above structural unit
When the polycondensation is carried out, in addition to the components constituting the above (I), (II), (III) and (IV), 4,4′-diphenyldicarboxylic acid, 3,3′-diphenyldicarboxylic acid, 4'-
Diphenyldicarboxylic acid, 2,2'-diphenyldicarboxylic acid, 1,2-bis (phenoxy) ethane-4,4'-dicarboxylic acid, 1,2-bis (2-chlorophenoxy) ethane-
Aromatic dicarboxylic acids such as 4,4'-dicarboxylic acid, alicyclic dicarboxylic acids such as hexahydroterephthalic acid, resorcinol, aromatic dihydroxy compounds such as chlorohydroquinone, methylhydroquinone, 2,7-dihydroxynaphthalene, m-oxy Benzoic acid, aromatic oxycarboxylic acid such as 2,6-oxynaphthoic acid and p-aminophenol, p-aminobenzoic acid and the like can be further copolymerized in a small proportion that does not impair the object of the present invention. it can.

The liquid crystal polyester (B) in the present invention comprises the structural unit (I ′) or ((I ′), (II ′) and (II)
I ')].

The copolymerization amount of the above-mentioned structural units (I '), (II') and (III ') is arbitrary, but the copolymerization amount is preferred from the viewpoint of fluidity. That is, the structural unit (I ′) is represented by [(I ′)
+ (II ')], preferably from 30 to 100 mol%,
In particular, it is preferably 50 to 100 mol%. In particular, the structural unit (I ') is 90 to 100 of [(I') + (II ')].
In the case of mol%, 10 to 50 mol% of X It is preferred that

In the structural unit (II ′), 50 mol% or more of Y is —CH ₂ C
It is preferably H ₂ —, and 65 mol% or more of the carbonyl groups of the structural unit (III ′) are preferably in a para-position.

The liquid crystal polyester (B) in the present invention has a heat distortion temperature of less than 190 ° C. Above 190 ° C, moldability and fluidity are insufficient. The higher the heat deformation temperature, the better in terms of heat resistance.
Preferably it is 50 ° C. or more and less than 190 ° C.

The liquid crystal onset temperature of the liquid crystal polyester (B) in the present invention is not particularly limited, but is preferably from 220 to 280 ° C, particularly preferably from 230 to 270 ° C, from the balance between heat resistance and fluidity.

The melt viscosity of the liquid crystal polyester (B) in the present invention is not particularly limited, but is preferably 10,000 poise or less, particularly preferably 5,000 poise or less in terms of moldability and fluidity.
Most preferred is 3,000 poise or less.

The structural method of the liquid crystal polyester (B) comprising the structural unit is not particularly limited, and can be produced according to a known polyester polycondensation method.

For example, the structural unit (II ') and (III') may not be copolymerized and the structural unit (II ') and (III') are copolymerized, ₂ -X- is -CH CH ₂
In cases other than-, the following (1) to (4), -X- is -CH ₂ CH ₂
In the case of-, the production method (5) is preferably mentioned.

(1) p-acetoxybenzoic acid, 6-acetoxy-2
-Naphthoic acid, 4,4'-diacetoxybiphenyl, 1,4-
A method of producing from a diacylated aromatic dihydroxy compound such as diacetoxybenzene and an aromatic dicarboxylic acid such as terephthalic acid by a deacetic acid polycondensation reaction.

(2) p-hydroxybenzoic acid, 6-hydroxy-2
-Reaction of aromatic dihydroxy compounds such as naphthoic acid, 4,4'-dihydroxybiphenyl and hydroquinone, and aromatic dicarboxylic acids such as terephthalic acid with acetic anhydride to acylate the phenolic hydroxyl group, followed by deacetic acid polycondensation reaction How to manufacture by.

(3) phenyl ester of p-hydroxybenzoic acid,
Phenyl ester of 6-hydroxy-2-naphthoic acid,
A method of producing from an aromatic dihydroxy compound such as 4,4'-dihydroxybiphenyl or hydroquinone and a diphenyl ester of an aromatic dicarboxylic acid such as terephthalic acid by a phenol removal polycondensation reaction.

(4) p-hydroxybenzoic acid, 6-hydroxy-2
A desired amount of an aromatic dicarboxylic acid such as naphthoic acid or terephthalic acid is reacted with diphenyl carbonate to form a diphenyl ester, and then an aromatic dihydroxy compound such as 4,4'-dihydroxybiphenyl or hydroquinone is added thereto to remove phenol. A method of producing by a condensation reaction.

(5) In the presence of polyethylene terephthalate (1)
Or a method of manufacturing by the method of (2).

Since a high polymer liquid crystal polyester (B) is obtained,
It is more preferable to use the method of (1), (2) or (5).

Typical catalysts used in the polycondensation reaction include metal compounds such as stannous acetate, tetrabutyl titanate, potassium acetate, antimony trioxide, magnesium, sodium acetate, and zinc acetate. It is effective for

Some liquid crystal polyesters (B) comprising the above structural units can be measured for intrinsic viscosity in pentafluorophenol. In this case, the concentration measured at 60 ° C. at a concentration of 0.1 g / dl is 0.1 dl. / g or more is preferable, especially 0.5 to 15.0 dl
/ g is preferred.

The liquid crystal polyester (B) comprising the above structural unit
When polycondensation is carried out, the above (I '), (II') and (II)
In addition to the components constituting I '), 4,4'-diphenyldicarboxylic acid, 3,3'-diphenyldicarboxylic acid, 3,4'-diphenyldicarboxylic acid, 2,2'-diphenyldicarboxylic acid, 1,2- Bis (phenoxy) ethane-4,4'-dicarboxylic acid, 1,2-bis (2-chlorophenoxy) ethane-4,
Aromatic dicarboxylic acids such as 4'-dicarboxylic acid, alicyclic dicarboxylic acids such as hexahydroterephthalic acid, resorcinol, aromatic dihydroxy compounds such as 2,7-dihydroxynaphthalene, p- (2-hydroxyethoxy) benzoic acid, Aromatic oxycarboxylic acids such as m-oxybenzoic acid and p-aminophenol, p-aminobenzoic acid and the like can be further copolymerized in a small proportion that does not impair the object of the present invention.

In the present invention, the compounding amount of the liquid crystal polyester (A) is
It is 99 to 1% by weight, preferably 95 to 5% by weight, particularly preferably 90 to 10% by weight, and the compounding amount of the liquid crystal polyester (B) is 1 to 99% by weight, preferably 5 to 95% by weight, particularly preferably. Is from 10 to 90% by weight. Liquid crystal polyester (A)
A liquid crystal polyester resin composition excellent in heat resistance, fluidity and rigidity can be obtained in the range of 99 to 1% by weight.

The liquid crystal polyester resin composition comprising the liquid crystal polyester (A) and the liquid crystal polyester (B) has good compatibility with the following thermoplastic resin (C), and improves the properties of the thermoplastic resin (C). be able to.

Although the thermoplastic resin (C) is not particularly limited, polyamide, polyoxymethylene, polycarbonate, polyarylene oxide, polyalkylene terephthalate, polyarylene sulfide, polysulfone, polyethersulfone, amorphous polyarylate, polyetheretherketone Are used.

Preferred specific examples of the thermoplastic resin (C) include the following.

Examples of the polyamide include nylon 6, nylon 46, nylon 66, nylon 610, nylon 11, nylon 12, and the like, and copolymers thereof. Polyoxymethylene includes polyoxymethylene homopolymers and copolymers in which the main chain is largely composed of oxymethylene chains. Polycarbonates are based on hydrocarbon derivatives containing bis (4-hydroxyphenyl), bis (3,5-dialkyl-4-hydroxyphenyl) or bis (3,5-dihalo-4-hydroxyphenyl) substitution Polycarbonates are preferred, especially polycarbonates based on 2,2-bis (4-hydroxyphenyl) propane (bisphenol A). Examples of polyarylene oxide include poly (2,6-dimethyl-1,4-phenylene) ether, 2,6-dimethylphenol / 2,4,6-trimethylphenol copolymer, 2,6
-Dimethylphenol / 2,3,6-triethylphenol copolymer and the like.

Styrene-based resins such as polystyrene and high-impact polystyrene can be added to polyarylene oxide.

Examples of the polyalkylene terephthalate include polyethylene terephthalate and polybutylene terebutarate.

Examples of polyarylene sulfide include polyphenylene sulfide.

Structural formula as polysulfone And the like.

Structural formula as polyether sulfone And the like.

The amorphous polyarylate has the structural formula Or And the like.

As polyetheretherketone, the structural formula, And the like. Among them, polyalkylene terephthalate and polyarylene sulfide are particularly preferably used.

The blending ratio of the thermoplastic resin (C) is 1-99% by weight based on 99-1% by weight of a composition comprising 99-1% by weight of liquid crystal polyester (A) and 1-99% by weight of liquid crystal polyester (B).
The preferred compounding ratio is 95 to 5% by weight / 5 to 95% by weight, more preferably 90 to 10% by weight / 10 to 90% by weight. When the compounding ratio of the liquid crystal polyethylene resin composition [(A) + (B)] and the thermoplastic resin (C) is in the range of 99 to 1% by weight / 1 to 99% by weight, the heat resistance, fluidity and rigidity are improved. Becomes larger.

Further, a reinforcing agent can be added to the liquid crystal polyester resin composition of the present invention in order to further improve heat resistance and mechanical properties. Specific examples of the reinforcing agent include fibrous, granular, and a mixture of both. As the fibrous reinforcing agent, glass fiber, shirasu glass fiber, alumina fiber,
Examples include inorganic fibers such as silicon carbide fibers, ceramic fibers, asbestos fibers, gypsum fibers, and metal fibers (for example, stainless steel fibers) and carbon fibers. Further, as a granular reinforcing agent, silicates such as wollastenite, sericite, kaolin, mica, clay, bentonite, asbestos, talc, alumina silicate, alumina,
Metal oxides such as silicon oxide, magnesium oxide, zirconium oxide and titanium oxide; carbonates such as calcium carbonate, magnesium carbonate and dolomite; calcium sulfate;
Examples thereof include sulfates such as barium sulfate, glass beads, boron nitride, silicon carbide, and Saroyan, and these may be hollow (for example, hollow glass fibers, glass microballoons, shirasu balloons, carbon balloons, and the like). If necessary, the above-mentioned reinforcing agent may be pretreated with a coupling agent such as a silane-based or titanium-based coupling agent before use.

The liquid crystal polyester resin composition of the present invention contains an antioxidant and a heat stabilizer (for example, hindered phenol, hydroquinone, and the like) within a range that does not impair the purpose of the present invention.
Phosphites and their substituted products), ultraviolet absorbers (eg, resorcinol, salicylate, benzotriazole, benzophenone, etc.), lubricants and mold release agents (montanic acid and its salts, esters, half esters, stearin alcohol, stearamide) And conventional additives such as colorants, flame retardants, plasticizers, antistatics and other thermoplastics, including dyes (eg, nitrosine) and pigments (eg, cadmium sulfide, phthalocyanine, carbon black). By adding a resin, predetermined characteristics can be imparted.

The liquid crystal polyester resin composition of the present invention is preferably prepared by melt-kneading, and a known method can be used for melt-kneading. For example, the composition can be melt-kneaded at a temperature of 200 to 400 ° C. using a Banbury mixer, a rubber roll machine, a kneader, a single-screw or twin-screw extruder, and the like to obtain a composition.

〔Example〕

 Hereinafter, the present invention will be described in detail with reference to examples.

Reference Example 1 466 parts by weight of p-hydroxybenzoic acid, 84 parts by weight of 4,4'-dihydroxybiphenyl, 480 parts by weight of acetic anhydride, 75 parts by weight of terephthalic acid and 130 parts by weight of polyethylene terephthalate having an intrinsic viscosity of about 0.6 dl / g The reaction vessel was equipped with a stirring blade and a distillation tube, and was subjected to deacetic acid polymerization under the following conditions.

First, under nitrogen atmosphere at 100-250 ° C for 5 hours,
After reacting at ~ 300 ° C for 1.5 hours, 0.3 hours at 300 ° C for 1 hour
After reducing the pressure to mmHg and further reacting for 3.75 hours to complete the polycondensation, almost the theoretical amount of acetic acid was distilled off to obtain a resin having the following theoretical structural formula.

l / m / n / o = 75/10/15/25 Further, the polyester was placed on a sample stage of a polarizing microscope and heated to confirm the optical anisotropy. As a result, the liquid crystal onset temperature was 272 ° C. And showed good optical anisotropy. The logarithmic viscosity of this polyester (measured in pentafluorophenol at a concentration of 0.1 g / dl at 60 ° C.) is 2.11 dl / g,
The melt viscosity at 312 ° C. and a shear rate of 1,000 / sec was 2,900 poise. The heat distortion temperature was 208 ° C. (the measuring method will be described later).

Reference Example 2 519 parts by weight of p-astoxybenzoic acid, 184 parts by weight of 4,4'-diacetoxybiphenyl, 85 parts by weight of t-butylhydroquinone diacetate, hydroquinone diacetate 1
9.4 parts by weight and 186 parts by weight of terephthalic acid were charged into a reaction vessel equipped with a stirring blade and a distillation
After reacting at ~ 340 ° C for 3.0 hours, the temperature is raised to 350 ° C and then 1.5mm
The system was decompressed to Hg, and further heated for 1.0 hour to carry out a polycondensation reaction to obtain a resin having the following theoretical structural formula.

l / m / n / o / p = 72/17 / 8.5 / 2.5 / 28 This polyester was placed on a sample stage of a polarizing microscope, and the temperature was raised to confirm the optical anisotropy. Was 307 ° C., showing good optical anisotropy. The logarithmic viscosity of this polyester (measured under the same conditions as in Reference Example 1) was 4.3 dl / g, and the melt viscosity at 347 ° C. and a shear rate of 1,000 / sec was 4,300 poise. The heat distortion temperature is 251
° C (the measuring method is described later).

Reference Example 3 541 parts by weight of p-acetoxybenzoic acid, 184 parts by weight of 4,4'-diacetoxybiphenyl, 62 parts by weight of hydroquinone diacetate, 124 parts by weight of terephthalic acid, and 42 parts by weight of isophthalic acid were stirred with a stirring blade and a distillation tube. After reacting at 250 to 360 ° C. for 3 hours under a nitrogen gas atmosphere, the pressure was reduced to 1 mmHg, and the mixture was further heated for 1 hour to complete the polycondensation, thereby obtaining a resin having the following theoretical structural formula. Obtained.

l / m / n / o / p = 75/17/8 / 18.75 / 6.25 This polyester was placed on a sample stage of a polarizing microscope, and the temperature was raised to confirm the optical anisotropy.
305 ° C., showing good optical anisotropy. The logarithmic viscosity of this polyester (measured under the same conditions as in Reference Example 1) is 4.
The melt viscosity at 345 ° C and a shear rate of 1,000 / sec is 1dl / g.
It was 3,500 poise. The heat distortion temperature was 264 ° C. (the measuring method will be described later).

Reference Example 4 72.58 parts by weight of p-acetoxybenzoic acid and 51.61 parts by weight of polyethylene terephthalate having an intrinsic viscosity of about 0.6 dl / g were charged into a reaction vessel equipped with a stirring blade and a distilling tube, and heated to 200 to 250 ° C. under a nitrogen gas atmosphere. After 5 hours at 250-280 ° C for 2 hours, the pressure was reduced to 0.6 mmHg for 1 hour at 280 ° C, and the reaction was further performed for 2 hours. Was obtained.

l / m / n = 60/40/40 Also, as a result of placing this polyester on a sample stage of a polarizing microscope, raising the temperature and observing the optical anisotropy, the liquid crystal onset temperature was 240 ° C. High optical anisotropy. The logarithmic viscosity of the polyester (measured under the same conditions as in Reference Example 1) was 0.71 dl / g, and the melt viscosity at 280 ° C. and a shear rate of 1,000 / sec was 820 poise. The heat distortion temperature is 64
° C (the measuring method is described later).

Reference Example 5 101.88 parts by weight of p-acetoxybenzoic acid, 43.40 parts by weight of 6-acetoxy-2-naphthoic acid and heat-resistant agent V 0.1
A weight part was charged into a reaction vessel equipped with a stirring blade and a distillation tube, and reacted at 250 to 280 ° C. for 3 hours in a nitrogen gas atmosphere.
After the temperature was raised to 0 ° C., the pressure inside the system was reduced to 0.8 mmHg, and the system was further heated for 2 hours to carry out a polycondensation reaction, and a polymer melt was taken out and cooled. The structural formula of the polymer is shown below.

Further, the polyester was placed on a sample stage of a polarizing microscope, heated, and the optical anisotropy was observed. As a result, the liquid crystal onset temperature was 256 ° C., indicating good optical anisotropy. The logarithmic viscosity of the polyester (measured under the same conditions as in Reference Example 1) was 4.51 dl / g, and the melt viscosity at 296 ° C. and a shear rate of 1,000 / sec was 1,700 poise. The heat distortion temperature is 1
The temperature was 78 ° C (the measurement method is described later).

Examples 1 to 9 Liquid crystal polyesters (A) of Reference Examples 1 to 3 and Reference Examples 4 and 5
The liquid crystal polyester (B) was dry-blended at a predetermined ratio, and then melt-kneaded and pelletized with a 30 mmφ twin screw extruder set at 300 to 350 ° C.

Sumitomo Nestal injection molding machine
40/25 (manufactured by Sumitomo Heavy Industries, Ltd.), a 1/8 ″ × 1/2 ″ × 5 ″ test piece was formed at a cylinder temperature of 300 to 350 ° C. and a mold temperature of 90 ° C. The rod flow length was measured using a 0.3 mm × 12.5 mm × 150 mm cavity under the conditions of a filling pressure of 90% and an injection speed of 90%, and the heat deformation temperature was measured using a heat deformation temperature measuring device manufactured by Toyo Seiki. The heat distortion temperature (18.6 kg / cm ² ) of the / 8 ″ thick test piece was measured. In addition, 1/8 ″
Thick test piece, manufactured by Toyo Baldwin Co., Ltd., Tensilon UTM
Using -100, the flexural modulus was measured under the conditions of a strain rate of 1 mm / min and a span distance of 50 mm. The results are shown in Table 1.

Comparative Examples 1 to 5 The liquid crystal polyesters (A) of Reference Examples 1 to 3 and Reference Examples 4 and 5
The liquid crystal polyester (B) was injection molded in the same manner as in Examples 1 to 9 and evaluated. The results are shown in Table 1.

Comparative Examples 6 to 8 having the following structural formula, liquid crystal onset temperature of 216 ° C., logarithmic viscosity of 5.1
Melt viscosity at 3dl / g, 301 ° C, shear rate 1,000 / sec is 2,400
A polymer having a poise and a heat deformation temperature of 207 ° C. (the measurement method will be described later) is referred to as a resin (D).

l / m / n = 75/25/25 Having the following structural formula, liquid crystal onset temperature 296 ° C., logarithmic viscosity 1.9
Melt viscosity at 5 dl / g, 336 ° C, shear rate 1,000 / sec, 4,700
A polymer having a poise and a heat deformation temperature of 234 ° C. (the measurement method will be described later) is referred to as a resin (E).

l / m / n / o = 60/40/20/20 After resin (D) and resin (E) were dry-blended at a predetermined ratio, they were melt-kneaded and pentized by a 30 mmφ twin-screw extruder set at 340 ° C. .

The polymers and resins (D) and (E) were injection molded in the same manner as in Examples 1 to 9 and evaluated. Table 2 shows the results together.

As can be seen from Table 1, the liquid crystal polyester resin compositions of the present invention of Examples 1 to 9 were compared with the liquid crystal polyesters of Comparative Examples 1 to 5 in terms of both the heat deformation temperature, the flow length of the rod, and the flexural modulus, which were simply higher than the arithmetic average. And excellent in heat resistance, fluidity and rigidity.

As can be seen from Table 2, Example 1 for Comparative Examples 6 to 8
The liquid crystal polyester resin compositions of Nos. To 9 of the present invention have large values of the rod flow length and the flexural modulus, and are excellent in fluidity and rigidity.

Examples 10 to 25, Comparative Examples 25 to 47 The liquid crystal polyesters (A) of Reference Examples 1 to 3 and Reference Examples 4 and 5
After dry-blending a predetermined ratio of the liquid crystal polyester (B) and the thermoplastic resin (C) shown in Table 2, a temperature of 300 to 370 ° C.
The mixture was melt-kneaded and pelletized with a twin screw extruder having a diameter of 30 mm.

Sumitomo Nestal injection molding machine
40/25 (manufactured by Sumitomo Heavy Industries, Ltd.) at a cylinder temperature of 300 to 370 ° C and a mold temperature of 90 to 180 ° C, 1/8 "x 1/2" x
A 5 ″ test piece and ASTM No. 1 dumbbell were molded.
The flexural modulus of a 1/8 ″ thick test piece was measured using Tensilon UTM-100 manufactured by Toyo Ballwin Co., under the conditions of a strain rate of 1 mm / min and a span distance of 50 mm.
The tensile strength was measured using ASTM No. 1 dumbbell based on ASTM D638 standard. Then rub the 1/8 "thick test specimen several times by hand.
The presence or absence of surface peeling was visually determined. Table 3 shows the results together.

Comparative Examples 9 to 24 The liquid crystal polyesters (A) of Reference Examples 1 to 3 and Reference Examples 4 and 5
The liquid crystal polyester (B) and the thermoplastic resin (C) shown in Table 3 were injection molded and evaluated in the same manner as in Examples 10 to 25 and Comparative Examples 25 to 47. Table 3 shows the results together.

Comparative Examples 48 to 50 Resin (D), resin (E) and thermoplastic resin (C) shown in Table 4 were dry blended, melt-kneaded, pelletized, and injected in the same manner as in Examples 10 to 25 and Comparative Examples 25 to 47. Molding and evaluation. Table 4 shows the results together.

As shown in Table 3, the liquid crystal polyester resin compositions of the present invention of Examples 10 to 25 have higher flexural modulus and tensile strength than Comparative Examples 14 to 47, and are excellent in rigidity and mechanical properties. In addition, there is no peeling of the surface of the molded product as compared with Comparative Examples 9 to 13, and the peeling resistance is excellent. As can be seen from Table 4, the flexural modulus and the tensile strength are both high and the rigidity and the mechanical properties are superior to Comparative Examples 48 to 50.

[Effects of the Invention] The present invention provides a liquid crystal polyester resin composition having excellent heat resistance, fluidity, rigidity, mechanical properties and peeling resistance by blending two kinds of liquid crystal polyesters having different liquid crystal onset temperatures. Can be

Claims (2)

(57) [Claims] 1. A liquid crystalline polyester (A) having a heat distortion temperature of 190 to 280 ° C., comprising 99 to 1% by weight of the following structural units (I), (II), (III) and (IV): ') Or ((I'), (II ') and (III')) having a heat distortion temperature of less than 190 ° C.
A liquid crystal polyester resin composition comprising 9% by weight. O-X-O (III) (However, X in the formula is Represents one or more groups selected from —CH ₂ CH ₂ —, wherein the carbonyl groups of the structural unit (IV) are in a para- and / or meta-position with each other, and 50 mol% or more of them are in the para-position. The structural units [(II) + (III)] and (IV) are substantially equimolar. ) OY'-O ... (II ') (Where X 'in the formula is Y ' And one or more groups selected from —CH ₂ CH ₂ — and the carbonyl groups of the structural unit (III ′) are para and / or
Or they are in a meta position. The structural units (II ') and (III') are substantially equimolar. ) " 2. A liquid crystal polyester resin composition comprising 99 to 1% by weight of the liquid crystal polyester resin composition according to (1) and 1 to 90% by weight of another thermoplastic resin (C).