JP3362481B2 - Method for producing liquid crystalline resin composition molded article - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a composition comprising a liquid crystalline polyester resin having a low linear expansion coefficient and a thermoplastic resin, which is useful as an electric / electronic device part, an automobile part, a mechanical part, etc., and which has excellent mechanical properties and heat resistance. It relates to molded articles .

[0002]

2. Description of the Related Art In recent years, the demand for higher performance of plastics has been increasing, and many polymers having various new properties have been developed. Among them, an optically anisotropic liquid crystal characterized by parallel arrangement of molecular chains. Resin, specifically liquid crystal
-Based polyester resins have been attracting attention because they have excellent fluidity and mechanical properties. However, liquid crystalline polyester
Currently, resin is limited in its application because of its different molding shrinkage and mechanical properties in the direction perpendicular to the molecular chain orientation direction and its high price. On the other hand, it is known that many thermoplastic resins are not necessarily sufficient in mechanical properties and heat resistance as compared with liquid crystal resins.

Therefore, in order to solve the drawbacks of both, a blend of a liquid crystalline resin and a thermoplastic resin has been attracting attention (for example, JP-A-57-25354).

[0004]

However, although the mechanical properties of the thermoplastic resin composition are improved by blending and molding the liquid crystalline resin, the physical properties which are sufficiently satisfied because the orientation of the liquid crystalline resin is relaxed during the molding process. The current situation is that no one has been obtained. Further, in the case of a thick test piece, this orientation relaxation is very large, and there is a problem that the reinforcing effect is hardly seen.

The present invention solves the above-mentioned problems, is excellent in mechanical properties and heat resistance, and has a low linear expansion coefficient for molding a liquid crystalline resin composition.
The challenge is to obtain goods .

[0006]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found that a composition obtained by melt-kneading a thermoplastic resin (A) and a liquid crystalline polyester resin (B) having a specific structure is kneaded. It has been found that injection molding or extrusion molding within a certain temperature range suppresses orientation relaxation of the liquid crystalline polyester resin (B) , improves mechanical properties, and lowers the coefficient of linear expansion, and thus reached the present invention.

That is, the present invention comprises (A) 99 to 50% by weight of a thermoplastic resin and (B) 1 to 50% by weight of a liquid crystalline polyester resin composed of a specific structural unit and capable of forming an anisotropic molten phase. kneaded at a liquid crystal starting temperature or higher of the liquid crystal polyester resin (B), liquid crystal initiation temperature or higher of the liquid crystal polyester resin (B), and injection molding or extrusion at least the melting point of the molding temperature of the thermoplastic resin (a) In molding, the shear rate dependence curve of the melt viscosity of the liquid crystalline polyester resin (B) at the molding temperature is the same as the shear rate dependence curve of the melt viscosity of the thermoplastic resin (A) measured at the same temperature.
A method for producing a molded article of a liquid crystalline resin composition, characterized by using a thermoplastic resin (A) and a liquid crystalline polyester resin (B) which intersect within a shear rate range of up to 2000 / sec. is there.

The compounds specifically used in the present invention will be described in detail below.

Preferred specific examples of the thermoplastic resin (A) used in the present invention include crystalline resins such as polyester, polyamide, polyarylene sulfide, polyoxymethylene, polypropylene, polyethylene and polystyrene, polycarbonate, polyarylate and polyarylene oxide. Amorphous resins such as Among these, polyester, polyarylene sulfide, polypropylene, polyethylene, polycarbonate is preferable,
Most preferred is polyester. Further, two or more kinds of this thermoplastic resin may be used. The shear rate dependence curve of the melt viscosity at the molding temperature of the thermoplastic resin (A) used here is the shear rate dependence of the liquid crystalline resin (B) measured at the same temperature in the shear rate region of 10 to 2000 / sec. It is necessary to cross the curve. Further, the melt viscosity of the liquid crystalline resin (B) is preferably lower than the melt viscosity of the thermoplastic resin (A) on the high shear side and high on the low shear side. If they do not intersect, the present invention cannot be achieved because the orientation of the molecular chains is not sufficient or the orientation relaxation of the molecular chains occurs easily. When two or more thermoplastic resins are used, it is necessary that the shear rate dependence curve of the melt viscosity of this blend and the curve of the liquid crystalline resin (B) intersect. The melt viscosity is a value measured by a high pressure type capillary viscometer using a capillary having a diameter d1 mm and a length l ≧ 5 mm.

The thermoplastic polyester is a thermoplastic polyester having an aromatic ring as a chain unit of a polymer, and includes an aromatic dicarboxylic acid (or its ester-forming derivative) and a diol (or its ester-forming derivative). Is a polymer or copolymer obtained by a condensation reaction containing as a main component. Examples of the dicarboxylic acid used herein include terephthalic acid, isophthalic acid, phthalic acid, 2,
6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, bis (p
-Carboxyphenyl) methane, anthracene dicarboxylic acid, 4,4'-biphenylcarboxylic acid, 4,4'-diphenylethercarboxylic acid, 1,2-bis (p-carboxyphenoxy) ethane, or an ester-forming derivative thereof. To be If it is 30 mol% or less, aliphatic dicarboxylic acids such as adipic acid, sebacic acid, azelaic acid, dodecanedioic acid and dimer acid, 1,
It may be substituted with an alicyclic carboxylic acid such as 4-cyclohexanedicarboxylic acid or 1,3-cyclohexanedicarboxylic acid. As the diol component, an aliphatic diol having 2 to 10 carbon atoms, that is, ethylene glycol, propylene glycol, butylene glycol, 1,5-pentane glycol, decamethylene glycol, 3-methyl-
1,3-propenediol, neopentyl glycol,
Examples thereof include, but are not limited to, cyclohexanedimethanol and cyclohexanediol. Specific examples of preferable polyesters include polyethylene terephthalate, polybutylene terephthalate, polyethylene-1,2-bis (phenoxy) ethane-4,
4'-dicarboxylate, polyethylene-2,6-naphthalate, poly-1,4-cyclohexanedimethylene terephthalate, etc. and polyethylene terephthalate / isophthalate, polybutylene terephthalate / isophthalate, polybutylene terephthalate / sebacate, polybutylene terephthalate / Copolyesters such as decane dicarboxylate and poly-1,4-cyclohexane dimethylene terephthalate / isophthalate may be mentioned. Among these, preferred polyesters include polybutylene terephthalate, polyethylene terephthalate, and poly-1,4-cyclohexanedimethylene terephthalate. Furthermore, polybutylene terephthalate is more preferable. The logarithmic viscosity of polybutylene terephthalate is preferably 0.9 to 1.3, more preferably 0.92 to 1.25.
The logarithmic viscosity of polybutylene terephthalate is 25
It was determined by dividing the logarithm of the relative viscosity obtained by using a 0.5% orthochlorophenol solution at 0 ° C. by the concentration.

As the polyamide, polyamide obtained from ω-amino acid or ω-lactam, or dicarboxylic acid such as diamine or m-xylenediamine and adipic acid, sebacic acid, dodecanedioic acid, cyclohexanedicarboxylic acid, terephthalic acid or isophthalic acid. And homopolymers or copolymers obtained from the above, mixed polymers and the like. Preferred polyamides are homopolyamides such as nylon 6, nylon 11, nylon 12, nylon 46, nylon 66, and adipic acid / terephthalic acid / hexamethylenediamine, adipic acid / 1,4-cyclohexanedicarboxylic acid / hexamethylenediamine, adipine. Examples thereof include copolyamides such as acid / 1,3-cyclohexanedicarboxylic acid / hexamethylenediamine, terephthalic acid / isophthalic acid / hexamethylenediamine / paraaminocyclohexylmethane.

The polyarylene sulfide is a bond of an aromatic ring and sulfur. Preferred polyarylene sulfides include polyparaphenylene sulfide, which may be partially branched.

Examples of the polyoxymethylene include polyoxymethylene homopolymers and copolymers in which the main chain has a majority of oxymethylene chains.

As the polypropylene, in addition to a homopolymer of propylene, a block or random copolymer obtained by copolymerizing propylene and other α-olefins (eg ethylene, butene-1 etc.) is also contained, and the ethylene content is 50 mol. % Copolymer of ethylene and α-olefin having 3 or more carbon atoms (for example, ethylene / propylene copolymer, ethylene / butene-1 copolymer, etc.), ethylene, α-olefin having 3 or more carbon atoms and non-conjugated It may contain a copolymer composed of a diene (for example, an ethylene / propylene / 1,4-hexadiene copolymer, an ethylene / propylene / dicyclopentadiene copolymer, an ethylene / propylene / ethylidene norbornene copolymer). . Preferred polypropylenes include polypropylene homopolymers, propylene / ethylene copolymers having an ethylene content of 30 mol% or less, or ethylene-α-olefin copolymers having an ethylene content of 50 mol% or more, or ethylene and carbon. Α of number 3 or more
-A polypropylene homopolymer containing 50% by weight or less of an elastomeric copolymer composed of an olefin and a non-conjugated diene, and a propylene / ethylene copolymer having an ethylene content of 30 mol% or less. Those modified with an unsaturated carboxylic acid or a derivative thereof are more preferable. Examples of the unsaturated carboxylic acid to be modified include acrylic acid, methacrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, 5-norbornene-2,3-dicarboxylic acid, tetrahydrophthalic acid and dimer acid. Examples of the derivative include anhydrides, esters, amides, imides and salts of the above acids.

The polyethylene includes not only a homopolymer of ethylene but also a block or random copolymer obtained by copolymerizing ethylene with another α-olefin (eg, propylene, butene-1). Those modified with the above-mentioned unsaturated carboxylic acid or its derivative are more preferable.

As the polystyrene, in addition to polystyrene homopolymer, HIPS (high impact polystyrene), A
S (acrylonitrile / styrene copolymer), ABS
(Acrylonitrile / butadiene / styrene copolymer), MBS (methyl methacrylate / butadiene / styrene copolymer) and the like.

As the polycarbonate or polyarylate, bis (4-hydroxyphenyl), bis (3,
5-dialkyl-4-hydroxyphenyl) or hydrocarbon derivatives having bis (3,5-dihalo-4-hydroxyphenyl) substitution are preferred.
Polycarbonates or polyarylates based on 2,2-bis (4-hydroxyphenyl) propane (bisphenol A) are particularly preferred. Moreover, these may contain a small amount of copolymerization components.

As the polyarylene oxide, 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 can be mentioned. These can be used by modifying with unsaturated carboxylic acid or its derivative by graft reaction. The unsaturated carboxylic acid to be modified is acrylic acid, methacrylic acid,
Crotonic acid, maleic acid, fumaric acid, itaconic acid, 5
-Norbornene-2,3-dicarboxylic acid, tetrahydrophthalic acid, dimer acid and the like. Examples of the derivative include anhydrides, esters, amides, imides and salts of the above acids. Further, styrene resins such as polystyrene and high impact polystyrene can be added to the polyarylene oxide.

As the liquid crystalline polyester resin, p-hi
Polyoxyethylene terephthalate co-weighed with droxybenzoic acid
Combined liquid crystalline resin (JP-A-49-72393),
p-Hydroxybenzoic acid and 6-hydroxy-2-naphtho
Liquid crystalline resin copolymerized with carboxylic acid (Japanese Patent Laid-Open No. 54-77691)
Liquid crystal properties used in the present invention.
Polyester resin (B) (hereinafter, liquid crystal resin (B)
Is sometimes called liquid crystal polyester. ) Is a liquid crystal polyester consisting of the following structural units (I), (II), (III), and (IV) .
Ri, most preferable results are obtained in terms of high improvement and orientation of the mechanical properties.

[0020]

[Chemical 4] (However, R ₁ is

[Chemical 5] R ₁ represents one or more groups selected from

[Chemical 6] Represents one or more groups selected from In the formula, X represents a hydrogen atom or a chlorine atom, and the structural units (II) and (III)
Total a structural unit (IV) is substantially equimolar. ) The above structural unit of the preferred liquid crystalline resin (B) used in the present invention
(I) is a structural unit of polyester produced from p-hydroxybenzoic acid, and structural unit (II) is 4,4'-dihydroxybiphenyl, 3,3 ', 5,5'-tetramethyl-4,4. From'-dihydroxybiphenyl, hydroquinone, t-butylhydroquinone, phenylhydroquinone, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 2,2-bis (4-hydroxyphenyl) propane and 4,4'-dihydroxydiphenylether Structural units produced from selected aromatic dihydroxy compounds, structural units (III) are structural units produced from ethylene glycol, structural units (IV) are terephthalic acid, isophthalic acid, 4,4'-diphenylcarboxylic acid, 2,6-naphthalenedicarboxylic acid, 1,2-bis (phenoxy) ethane-4,4'-dicarboxylic acid Acid, 1,
2-bis (2-chlorophenoxy) ethane-4,4'-
Structural units formed from an aromatic dicarboxylic acid selected from dicarboxylic acid and diphenyl ether dicarboxylic acid are shown below. Of these, particularly when the structural unit (III) is included, R ₁ is

[Chemical 7] Is 70% by mole or more of the structural unit (II), and R ₂ is

[Chemical 8] Particularly preferably those having 70 mol% or more of the structural unit (IV).

The above structural units (I), (II), (III) and (I
The copolymerization amount of V) is arbitrary. However, from the viewpoint of fluidity, the following copolymerization amount is preferable. That is, when the structural unit (III) is included, the total of the structural units (I) and (II) is the structural unit (I) or (I
60-95 mol% is preferable with respect to the sum total of I) and (III) , and 70-92 mol% is more preferable. Further, the structural unit (III) is based on the total of the structural units (I), (II) and (III).
40 to 5 mol% is preferable, and 30 to 8 mol% is more preferable. Further, the molar ratio of the structural unit (I) to (II) [(I)
/ (II)] is preferably 75/25 to 95/5, more preferably 78 from the viewpoint of the balance between fluidity and mechanical properties.
/ 22 to 93/7. Further, the structural unit (IV) is substantially equimolar to the total of the structural units (II) and (III) .

On the other hand, when the structural unit (III) is not contained, the structural unit (I) is the structural unit (I) or the structural unit (I) in view of fluidity .
And (II) is preferably 40 to 90 mol%, particularly preferably 60 to 88 mol%, and the structural unit (IV) is substantially equimolar to the structural unit (II). is there.

In the condensation polymerization of the above preferred liquid crystal polyester, 3,3'-diphenyldicarboxylic acid, 2,2 'is used in addition to the components constituting the structural units (I) to (IV).
An aromatic dicarboxylic acid 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'-dihydroxydiphenyl sulfone, 4,4 ' -Dihydroxydiphenyl sulfide, aromatic diol such as 4,4'-dihydroxybenzophenone, 1,4-butanediol, 1,6-
Hexanediol, neopentyl glycol, 1,4-
Aliphatic and alicyclic diols such as cyclohexanediol and 1,4-cyclohexanedimethanol, and aromatic hydroxycarboxylic acids such as m-hydroxybenzoic acid and 2,6-hydroxynaphthoic acid, and p-aminophenol and p-aminobenzoic acid An acid or the like may be copolymerized in an amount that does not impair the object of the present invention.

The method for producing the liquid crystalline resin (B) in the present invention is not particularly limited, and it can be produced according to a known polyester polycondensation method. For example, among the liquid crystal polyesters that can be preferably used, the production methods (1) to (4) are preferable when the structural unit (III) is not contained, and the production method (5) is preferable when the structural unit (III) is contained.

(1) p-acetoxybenzoic acid and 4,
A method for producing a diacylated aromatic dihydroxy compound such as 4′-diacetoxybiphenyl and an aromatic dicarboxylic acid such as terephthalic acid by deacetic acid condensation polymerization reaction.

(2) p-hydroxybenzoic acid and 4,
A method in which an aromatic dihydroxy compound such as 4'-dihydroxybiphenyl and an aromatic dicarboxylic acid such as terephthalic acid are reacted with acetic anhydride to acylate a phenolic hydroxyl group, and then a deacetic acid polycondensation reaction is performed.

(3) Method for producing by dephenol polycondensation reaction from phenyl ester of p-hydroxybenzoic acid and aromatic dihydroxy compound such as 4,4'-dihydroxybiphenyl and diphenyl ester of aromatic dicarboxylic acid such as terephthalic acid .

(4) Aromatic dicarboxylic acids such as p-hydroxybenzoic acid and terephthalic acid are reacted with a predetermined amount of diphenyl carbonate to form diphenyl esters, and then aromatic dihydroxy compounds such as 4,4'-dihydroxybiphenyl. A method of producing a compound by adding a compound and performing a dephenol polycondensation reaction.

(5) Polyester polymers such as polyethylene terephthalate, oligomers or bis (β-
A method for producing by the method (1) or (2) in the presence of a bis (β-hydroxyethyl) ester of an aromatic dicarboxylic acid such as hydroxyethyl) terephthalate.

Typical examples of the catalyst used in the polycondensation reaction include stannous acetate, tetrabutyl titanate, potassium acetate, antimony trioxide, metal compounds such as sodium acetate, magnesium and the like. It is effective when

The liquid crystalline resin (B) used in the present invention is capable of measuring logarithmic viscosity in pentafluorophenol, and in that case, it is measured at a concentration of 0.1 g / dl at 60 ° C. The value obtained is preferably 0.5 or more. In particular, when the structural unit (III) is included, it is 1.0 to 3.
When 0 dl / g does not contain the structural unit (III), 2.
0 to 10.0 dl / g is preferable.

The liquid crystalline resin (B) used in the present invention
The melt viscosity of is preferably 10 to 20,000 poise, and more preferably 20 to 10,000 poise. The melt viscosity is a value measured by a high-pressure capillary viscometer using a capillary with a diameter of 1 mm and l ≧ 5 mm under a condition of melting point (Tm) + 10 ° C. and a shear rate of 1,000 / sec.

Here, the melting point (Tm) means the endothermic peak temperature (Tm1) observed in the differential calorimetric measurement, which is observed when the temperature of the polymerized polymer is measured from room temperature to 20 ° C./min. , Tm1 + 20 ° C. for 5 minutes, then once cooled to room temperature under a temperature lowering condition of 20 ° C./min, and then measured again under a temperature rising condition of 20 ° C./min, the endothermic peak temperature (Tm2) observed Refers to. The liquid crystal starting temperature (TN) is the temperature at which opalescence is emitted under shear stress by heating the sample on a sample stage of a polarizing microscope.

As a method for mixing the liquid crystal resin (A) and the thermoplastic resin (B), various methods can be applied. Examples of the apparatus for melt mixing include a mixing roll, a Banbury mixer, a kneader, an extruder, and the like.
Of these, an extruder is preferable. This extruder is a single screw,
Alternatively, any of those having two or more screws can be used, but it is particularly preferable to use a twin screw extruder. The kneading temperature is preferably higher than the melting point of the thermoplastic resin (A) and higher than the liquid crystal starting temperature of the liquid crystalline resin (B), more preferably higher than the melting point of the liquid crystalline resin (B). .

When a molded article is obtained from the liquid crystalline resin composition of the present invention, usual methods such as injection molding, extrusion molding and blow molding can be applied, but extrusion molding and injection molding are particularly preferable. In the present invention, the temperature at which molding is performed by these methods is the same as that of the thermoplastic resin (A) measured at the same temperature as the shear rate dependence curve of the melt viscosity of the liquid crystalline resin (B).
It is specified by the relationship with the shear rate dependence curve of melt viscosity . Depending on the temperature to be measured, these curves may or may not intersect, but the present invention requires molding in the intersecting temperature range. When they do not intersect, the effect of improving the physical properties is very small. Furthermore, this optimum molding temperature is a temperature above the liquid crystal starting temperature of the liquid crystalline resin (B), and
The intersection of the shear rate dependence curves of melt viscosity is 10-20
It is necessary that the temperature is within the shear rate range of 00 / sec, and in the case of injection molding, the temperature intersecting at 50 to 1000 / sec is more preferable, and the temperature intersecting at 100 to 1000 / sec is more preferable. Is more preferable. Further, in the case of extrusion molding, it is preferable that the intersection point of the shear rate dependence curve of the melt viscosity is within the shear rate range of 10 to 1000 / sec, and it is more preferable that the intersection point is 10 to 500 / sec. It should be noted that this molding temperature needs to be higher than the melting point of the thermoplastic resin (A). When molded in these temperature ranges, the molecular chains of the liquid crystalline resin (B) are sufficiently oriented and the relaxation of the orientation of the molecular chains is suppressed. The improvement effect is expressed. The molding temperature in the present invention indicates the resin temperature before injection and is different from the set temperature of the equipment. Further, the melt viscosity is a diameter d1 mm, a length l ≧
It is a value measured by a high pressure type capillary viscometer using a 5 mm capillary.

The orientation relaxation of the liquid crystalline resin (B) generally increases as the thickness of the molded product increases. The effect of improving mechanical properties when molded at the molding temperature as described above becomes greater as the thickness of the test piece increases. In order to realize this effect, the thickness of the molded product is preferably 1 mm or more, more preferably 2 mm or more.
Not to. Further, it is preferable that a portion having such a thickness occupies 50% or more of the entire molded product.

In the present invention, a composition consisting only of the thermoplastic resin (A) and the liquid crystalline resin (B) is effective, but addition of an epoxy compound further improves mechanical properties, so that the epoxy compound is added. It is preferable.
The epoxy compound (C) used is a compound having two or more epoxy groups and is not necessarily limited, but a compound having two or more diglycidyl ester groups is preferable. Specifically, diglycidyl hexahydrophthalate, diglycidyl tetrahydrophthalate, glycidyl phthalate, diglycidyl terephthalate, diglycidyl isophthalate, glycidyl methacrylate, diglyceride dimer acid obtained by dimerizing dimer acid synthesized from stearic acid, 6 Those having two glycidyl ester groups such as diglycidyl-ethyl-1,11-dodecanedicarboxylate are preferred. Diglycidyl dimer may have a double bond in a straight chain or a ring. These diglycidyl esters may be used alone or in combination of two or more, or may be used in combination with diepoxy having a structure other than the above. Among these epoxy compounds, diglycidyl dimer and diglycidyl 6-ethyl-1,11-dodecanedicarboxylate are preferred. The epoxy equivalent of the epoxy compound used is preferably 100 or more, more preferably 200 or more.

The amount of the epoxy compound (C) in the composition of the present invention is such that the thermoplastic resin (A) and the liquid crystalline resin (B) are mixed.
0.01 to 100 parts by weight of the resin composition consisting of
The amount is 10 parts by weight, preferably 0.1 to 10 parts by weight.

In producing the liquid crystalline resin composition of the present invention, a conventionally known polyester polymerization catalyst,
Additives such as heat-resistant agents, weather-resistant agents, antistatic agents, dyes, colorants, crystal nucleating agents, flame retardants, talc, clay, mica, calcium metasilicate, silica sand, glass beads, glass flakes, graphite, titanic acid It is also possible to add inorganic fillers such as potassium whiskers and gypsum fibers, reinforcing agents such as glass fibers, asbestos fibers and carbon fibers.

[0040]

EXAMPLES The present invention will be described in more detail with reference to examples below, but these examples do not limit the scope of application of the present invention. In the examples, parts are parts by weight, PBT is polybutylene terephthalate, and PP is polypropylene.

Reference Example 1 p-Hydroxybenzoic acid 870 parts by weight, 4,4'-dihydroxybiphenyl 168 parts by weight, acetic anhydride 914 parts by weight, terephthalic acid 150 parts by weight and an intrinsic viscosity of about 0.
346 parts by weight of 6 dl / g polyethylene terephthalate was charged into a reaction vessel equipped with a stirring blade and a distillation tube, and deacetic acid polycondensation was carried out under the following reaction conditions.

After reacting at 100 to 250 ° C. for 1.5 hours in a nitrogen gas atmosphere, 290 ° C. and 0.5 m in 2 hours
When the pressure was reduced to mHg and the reaction was further continued for 1.0 hour to complete the polycondensation, almost the theoretical amount of acetic acid was distilled off, and a liquid crystal polyester (B-1) having the following theoretical structural formula was obtained.

[0043]

[Chemical 9] k / l / m / n = 70/10/20/30 The obtained polyester had a liquid crystal starting temperature of 235 ° C. and a melting point of 267 ° C.

Reference Example 2 907 parts by weight of p-hydroxybenzoic acid, 168 parts by weight of 4,4'-dihydroxybiphenyl, 914 parts by weight of acetic anhydride, 150 parts by weight of terephthalic acid and an intrinsic viscosity of about 0.
295 parts by weight of 6 dl / g polyethylene terephthalate was charged into a reaction vessel equipped with a stirring blade and a distillation tube, and deacetic acid polycondensation was carried out under the following reaction conditions.

After reacting in a nitrogen gas atmosphere at 100 to 250 ° C. for 1.5 hours, 290 ° C. and 0.5 m in 2 hours
When the pressure was reduced to mHg and the reaction was further continued for 1.0 hour to complete the polycondensation, almost the theoretical amount of acetic acid was distilled off, and a liquid crystal polyester (B-2) having the following theoretical structural formula was obtained.

[0046]

[Chemical 10] k / l / m / n = 73/10/17/27 liquid crystal starting temperature of the obtained polyester is 263 ° C., a melting point became 286 ° C..

Reference Example 3 According to JP-A-49-72393, 1296 parts by weight of p-acetoxybenzoic acid and an intrinsic viscosity of about 0.6 dl /
346 parts by weight of polyethylene terephthalate (g) was charged into a reaction vessel equipped with a stirring blade and a distilling tube to carry out polycondensation,
Liquid crystal polyester (B-3) was obtained.

The liquid crystal starting temperature of the obtained polyester is 2
The melting point was 60 ° C and the melting point was 283 ° C.

Examples 1 to 5 and Comparative Examples 1 to 10 (A) PBT (logarithmic viscosity 1.03 dl / g), PP, liquid crystalline resins (B-1) to (B-) polymerized in Reference Examples 1 to 3
3) was measured with a capillograph (manufactured by Toyo Seiki) using a die with l / d = 20/1. 1 to 4 are PBT or P used in Examples 1, 4 to 5 and Comparative Examples 7 to 9 described later, respectively.
3 is a graph showing the relationship between P and the shear rate dependence curve of melt viscosity at a molding temperature of a liquid crystalline resin. Table 1 shows the shear rates at the intersections when the melt viscosity curves at the respective molding temperatures intersect. Moreover, x represents that they do not intersect.

A predetermined amount of (A) PBT or PP and (B) the liquid crystalline resin polymerized in Reference Example were weighed and dry blended as shown in Table 1. 280 for PBT
In the case of ° C and PP, melt extrusion was performed with a 30 mmφ twin-screw extruder set to 290 ° C. With an injection molding machine set at a molding temperature and a mold temperature of 80 ° C. as shown in Table 1, 1/8 ”(3.2
mm) Thickness x 1/2 "width x 5" length test piece was molded. The flexural modulus was measured with Tensilon UTM-200 manufactured by Toyo Baldwin Co., Ltd. under the conditions of a strain rate of 1 mm / min and a span distance of 50 mm. Further, using this test piece, the lengths in the vertical direction at 23 ° C. and 80 ° C. were measured, and the coefficient of linear expansion was calculated.

The molding temperature mentioned here indicates the resin temperature of the polymer at the tip of the nozzle. Table 1 shows the results of these tests.

[0052]

[Table 1]

[0053]

[Table 2] Table 2 shows the bending elastic modulus and the coefficient of linear expansion of each liquid crystalline resin at the optimum molding temperature, which are extracted from Table 1. However, in the liquid crystalline resins (B-1) and (B-2) having a specific structure, ( It can be seen that the effect is greater than that of B-3).

Examples 6 to 9 and Comparative Examples 1 to 16 (A) PBT (intrinsic viscosity 1.20 dl / g), Reference Example 1
(B) liquid crystalline resin polymerized in 3 to 3, and (C) diglycidyl dimer (Epicote 871 manufactured by Yuka Shell Epoxy Co., Ltd.) were weighed in predetermined amounts as shown in Table 2 and dry blended. Melt extrusion was performed by a 30 mmφ twin-screw extruder set at 280 ° C. Test pieces similar to those of Examples 1 to 4 were molded by an injection molding machine set to the molding temperature and the mold temperature of 90 ° C. as shown in Table 2, and the bending elastic modulus and the linear expansion coefficient were measured in the same manner. Table 3 shows the results of these tests.

[0055]

[Table 3]

[0056]

The molded article obtained from the liquid crystalline resin composition according to the present invention is excellent in mechanical properties and heat resistance and has a low linear expansion coefficient. Therefore, it is widely used in electric and electronic equipment parts, automobile parts and the like. It is possible to use.

[Brief description of drawings]

FIG. 1 is a diagram showing the relationship between the melt viscosity and the shear rate of a polybutylene terephthalate (A) and a liquid crystalline resin (B-1) measured at 260 ° C.

FIG. 2 is a diagram showing the relationship between the melt viscosity of polybutylene terephthalate (A) and the liquid crystalline resin (B-2) measured at 285 ° C. and the shear rate.

FIG. 3 is a diagram showing a relationship between melt viscosity and shear rate of polybutylene terephthalate (A) and liquid crystalline resin (B-3) measured at 285 ° C.

FIG. 4 is a diagram showing the relationship between melt viscosity and shear rate of polypropylene (A) and liquid crystalline resin (B-1) measured at 260 ° C.

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Claims (2)

(57) [Claims] 1. An anisotropic molten phase comprising (A) 99 to 50% by weight of a thermoplastic resin and (B) the following structural units (I), (II), (III) and (IV). Liquid crystalline polyester
Le resin 1-50 wt% liquid crystalline polyester resin (B)
Kneaded at a liquid crystal starting temperature above the temperature of the liquid crystal polyester resin (B) liquid crystal starting temperature or more, and thermoplastic resin
In injection molding or extrusion molding at a molding temperature higher than the melting point of the fat (A), the shear rate dependence curve of the melt viscosity of the liquid crystalline polyester resin (B) at the molding temperature is the thermoplastic resin ( The thermoplastic resin (A) and the liquid crystalline polyester which intersect with the shear rate dependence curve of the melt viscosity of A) within the shear rate range of 10 to 2000 / sec.
A method for producing a liquid crystalline resin composition molded article, which comprises using a resin (B). [Chemical 1] (However, wherein R ₁ is ## STR2 ## It indicates one or more groups selected from, R ₂ is ## STR3 ## Represents one or more groups selected from In the formula, X is hydrogen
Represents an atom or chlorine atom, and has structural units (II) and (III)
And the structural unit (IV) are equimolar. ) 2. A total of 10 of the components (A) and (B).
Relative to 0 parts by weight, the epoxy compound having two or more (C) an epoxy group 0. It was added 01 to 10 parts by weight, and melt-kneaded at a liquid crystal starting temperature or higher of the liquid crystal polyester resin (B), liquid crystal initiation temperature or higher of the liquid crystal polyester resin (B), and the melting point of the thermoplastic resin (A) claims, wherein the benzalkonium be injection molding or extrusion molding the above molding temperature
Item 2. A method for producing a molded article of a liquid crystalline resin composition according to item 1 .