JPH1160925A - Thermoplastic resin composition and molded form thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition useful for molded forms high in mechanical strength and excellent in thin-wall fluidity and heat resistance by including two kinds of melt liquid crystalline polyester each having flow temperature within a specific range and a polyester composed of specific structural units each in specified proportion. SOLUTION: This composition comprises (A) a melt liquid crystalline polyester 310-400 deg.C in flow temperature, (B) another melt liquid crystalline polyester 270-370 deg.C in flow temperature, and (C) a polyester composed of recurring units of respective formulas I, II and III (X is -SO2 -, -CO- or the like; R1 is a 1-6C alkyl, 3-10C alkenyl or the like; (p) is 0-4; (m) and (n) are each 1-4); wherein the flow temperature difference between A and B is 10-60 deg.C, the amounts of A and B to be used are 1-99 pts.wt. and 99-1 pts.wt. based on 100 pts.wt. of A+B, respectively, and the amount of' C to be used is 1-99 pts.wt. based on 100 pts.wt. of A+B+C, and the proportions of the recurring units of formula I, II and III satisfy the following relationships: 0<=I<=99 mol%, II+III=100-I mol%, and 0.9<=II/III<=1.1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic resin composition having excellent thin-wall fluidity and excellent heat resistance and mechanical properties, and a molded article using the same.

[0002]

2. Description of the Related Art Molten liquid crystalline polyester does not entangle even in a molten state because molecules are rigid, forms a polydomain having a liquid crystal state, and exhibits a behavior in which molecular chains are remarkably oriented in the flow direction by shearing during molding. It is shown and generally called a liquid crystal polymer (thermotropic liquid crystal polymer). Due to this unique behavior, the melt fluidity is extremely excellent, and depending on the structure, it has a high deflection temperature under load and a continuous use temperature, and does not deform or foam even at a melting solder temperature of 260 ° C. or more. From this, the resin composition in which the molten liquid crystalline polyester was filled with a reinforcing material on the fiber represented by glass fiber, an inorganic filler represented by talc, and a heat stabilizer, etc., had a thin or complex shape. Electricity,
It is a suitable material for electronic components, and is used, for example, for relay components, coil bobbins, connectors, sealing of relay coils and ICs, volume components, commutators, motor components, and the like. On the other hand, blend compositions of various molten liquid crystalline polyesters and thermoplastic resins have been studied for the purpose of improving melt processability, mechanical strength, and the like. For example, JP-A-56-115357 discloses that a blend of a molten liquid crystalline polyester and another thermoplastic resin lowers the melt viscosity and improves the processability of the thermoplastic resin. Also, Japanese Patent Application Laid-Open No. 57-40551
Japanese Patent Application Laid-Open Publication No. H11-157, discloses that a composition having excellent mechanical strength can be obtained by blending a molten liquid crystalline polyester and a polycarbonate.

However, in general, different resins are often incompatible with each other. Therefore, if they are simply melt-kneaded, they form a coarse phase-separated structure in which the sea-island structure is disturbed, and have satisfactory physical properties such as mechanical strength. In many cases, it was not obtained, and the above-mentioned application sometimes caused inconvenience. In recent years, there has been a strong demand for thinner product shapes for electric and electronic components, and even for the electric and electronic components described above, further improvement in fluidity has been achieved while maintaining the conventional heat resistance and mechanical properties. It has been demanded. For example, Japanese Patent Application Laid-Open No.
A blend of a completely aromatic polyester forming a first anisotropic molten phase comprising a repeating unit containing 0 mol% or more of a naphthalene moiety and a completely aromatic polyester forming a second anisotropic molten phase is formed by a mechanical method. It is disclosed that the resulting polymer blend exhibits an anisotropic molten phase which does not show a significant decrease in mechanical properties (here, a completely aromatic polyester forming an anisotropic molten phase is a molten liquid crystalline polyester) Is a synonym for and is widely known in the art). However, the publication states that such polymer blends are the first
No mention is made as to whether or not to improve the flowability of the second or fully aromatic polyester. JP 59
JP-A-85733 discloses that the extrudability of a molten liquid crystalline polyester is improved by mixing a small amount of a liquid crystalline compound having a low molecular weight (less than 1,000) into the molten liquid crystalline polyester. However, the publication does not mention at all whether or not the fluidity at the time of injection molding is improved, and in general, since such low-molecular-weight compounds have low heat resistance, they cause thermal decomposition during molding and use. I do not endure. JP-A-3-252457 discloses that the flowability of a molten liquid crystalline polyester is improved by adding a small amount of an oligomer having p-hydroxybenzoic acid as a main component to the molten liquid crystalline polyester. However, this composition has unstable heat resistance typified by solder heat resistance and is not practical. JP-A-60-245632 discloses that a small amount of a polymeric fluidity modifier comprising terephthalic acid, p-hydroxybenzoic acid, hydroquinone, isophthalic acid and biphenol is added to aromatic oxybenzoyl polyesters. It is disclosed that the fluidity is improved. However, there is no description that this polymeric fluidity modifier is a molten liquid crystalline polyester, and there is no description about the fluidity improving effect in injection molding. Thus, with these methods, it is difficult to provide a material having high strength, excellent thin-wall fluidity, and good heat resistance.
In addition, the molten liquid crystalline polyester has a large anisotropy in shrinkage of a molded product obtained by injection molding, and often causes warpage or deformation. In particular, since small-sized electric / electronic parts require a precise dimensional accuracy of a thin portion, a material of a molten liquid crystalline polyester having good thin-wall fluidity and low anisotropy of shrinkage ratio has been desired.

[0004]

SUMMARY OF THE INVENTION The present invention relates to parts for automobiles and aircraft, industrial equipment, home appliances, OA equipment, electricity,
An object of the present invention is to provide a thermoplastic resin composition which can be suitably used for electronic parts and the like, and which provides a molded article having high strength, excellent thin-wall fluidity, and excellent heat resistance.

[0005]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, by selecting a polyester having a specific structure as a resin to be mixed with a molten liquid crystalline polyester, the above object has been achieved. We have achieved what we have achieved and arrived at the present invention. That is, the present invention is as follows. [1] The flow temperature defined below is 310 ° C. to 400 ° C.
C., a molten liquid crystalline polyester (A) having a flow temperature defined below of 270 ° C. to 370 ° C., and a polyester (C) defined below as essential components. , (A) and (B) have a flow temperature difference of 10 to 60 ° C., (A) 1 to 99 parts by weight, (B) 99 per 100 parts by weight of (A) and (B) in total.
-1 part by weight, and the total of (A), (B) and (C) is 1
A thermoplastic resin composition comprising 1 to 99 parts by weight of (C) per 100 parts by weight. Flow temperature: When using a capillary rheometer having a nozzle with an inner diameter of 1 mm and a length of 10 mm and extruding the heated melt from the nozzle at a rate of 4 ° C./min under a load of 100 kg / cm ² , the melt viscosity is Temperature indicating 48000 poise. Polyester (C):

[0006]

Embedded image (Wherein, X is _{-SO 2 -, - CO -,} - O -, - S-,
_{-CH 2 -, - CH 2 -CH} 2 -, - C (CH 3) 2 - and it is one or more selected from a single bond, R ₁ is an alkyl group having 1 to 6 carbon atoms , Carbon number 3-10
Represents an alkenyl group, a phenyl group or a halogen atom, p is an integer of 0 to 4, m and n are integers of 1 to 4. A plurality of each R ₁ on the same or different nuclei may be different from each other. Further, each p may be different from each other. ), Consisting of a repeating unit

[0007]

0 ≦ (I) ≦ 95 (mol%) (II) + (III) = 100− (I) (mol%) and 0.9 ≦ (II) / (III) ≦ 1.1 Polyester having a relationship. [2] In the repeating unit II of the polyester (C),
The thermoplastic resin composition according to [1], wherein X is —SO ₂ — and / or —C (CH ₃ ) ₂ —. [3] The molten liquid crystalline polyesters (A) and (B)
Each of the following structural units (IV), (V), (VI) and (VII), the molar ratio of V / IV is 0.2 to 1.0, and the molar ratio of (III + IV) / V is 0.1. 9 to 1.1, the VII / V molar ratio is 0 to 1, and the VII / V molar ratio (α) of the molten liquid crystalline polyester (A) and the VII of the molten liquid crystalline polyester (B)
The resin composition according to [1] or [2], wherein the ratio of / VI to the molar ratio (β), the molar ratio (α) / the molar ratio (β) is 0.1 to 0.5. Stuff.

[0008]

Embedded image [4] A molded article molded using the thermoplastic resin composition according to the above [1], [2] or [3].

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The molten liquid crystalline polyester used in the present invention has a flow temperature of 310 to 4 as defined above.
A liquid crystalline polyester (A) having a temperature of 00 ° C .;
370 ° C., and the difference between the flowing temperature of the molten liquid crystalline polyester (A) and the flowing temperature of the molten liquid crystalline polyester (B) is 10 to 60 ° C., preferably 20-60 ° C. When the difference in the flow temperature is less than 10 ° C., the desired effect of improving the thin-wall fluidity becomes insufficient, which is not preferable. On the other hand, if the difference in the flow temperature is larger than 60 ° C., the molding process becomes difficult due to the thermal decomposition of the molten liquid crystalline polyester (B), and a good molded product cannot be obtained. The molten liquid crystalline polyesters (A) and (B) used in the present invention have the structural units (IV), (V),
(VI), (VII), the molar ratio of V / IV is 0.2 to 1.0, the molar ratio of (VI + VII) / V is 0.9 to 1.1, and the molar ratio of VII / VI is 0. To 1 are preferred. These molten liquid crystalline polyesters are described, for example, in JP-B-47-47870. Further, a VII / VI molar ratio (α) of the molten liquid crystalline polyester (A) used in the present invention,
The ratio of the molten liquid crystalline polyester (B) to the VII / VI molar ratio (β), the molar ratio (α) / the molar ratio (β) is as follows:
Preferably 0.1-0.5, more preferably 0.3-
0.5. The mixing ratio of the molten liquid crystalline polyester (A) and the molten liquid crystalline polyester (B) used in the present invention is (A) 1 per 100 parts by weight of the total of (A) and (B).
To 99 parts by weight, (B) 99 to 1 parts by weight, preferably (A) 30 to 95 parts by weight, and (B) 70 to 5 parts by weight. If the compounding ratio of the molten liquid crystalline polyester (B) is less than 1 part by weight, the intended effect of improving thin-wall fluidity becomes insufficient, which is not preferable. On the other hand, if the blending ratio of the molten liquid crystalline polyester (B) is more than 99 parts by weight, the thin-wall fluidity is improved, but the heat resistance is greatly reduced, which is not preferable. The polyester (C) having a specific structure used in the present invention comprises the above repeating units I, II and III and satisfies the above formula.
When the content of (I) exceeds 95 mol%, the crystalline portion which does not melt is large, and the polyester and the thermoplastic resin are not dispersed during the production of the composition, which is not preferable. Also, (I
I) / (III) <0.9 or (II) / (II)
I)> 1.1 are not preferred because a sufficient high molecular weight product cannot be obtained during the production of polyester. Among, X is -SO ₂ - and / or -C (CH _{3) 2} -
It is preferred that The repeating unit I is 0 ≦
It is more preferable that (I) ≦ 80 (mol%).

The method for producing the polyester (C) having a specific structure used in the present invention includes, for example, a bisphenol component dissolved in an aqueous alkali solution and terephthalic acid chloride and / or isophthalic acid dissolved in an organic solvent such as a halogenated hydrocarbon. A method of polymerizing acid chloride and parahydroxybenzoic acid chloride in the presence of a catalyst, a method of polymerizing an acetylated bisphenol component and parahydroxybenzoic acid and terephthalic acid and / or isophthalic acid at a high temperature while removing acetic acid, bisphenol A method of polymerizing the components and phenyl ester of parahydroxybenzoic acid and phenylester of terephthalic acid and / or isophthalic acid at a high temperature while removing phenol, and further subjecting the thus obtained polyester to solid phase polymerization Law, and the like, but not limited thereto. The polyester (C) having a specific structure used in the present invention preferably has a flow temperature of 150 ° C to 450 ° C, and more preferably 280 ° C to 400 ° C, as measured by the method described below. More preferred. It is not preferable to blend a polyester having a flow temperature of lower than 150 ° C., since the polyester has a low molecular weight, which causes thermal deterioration during the production of the composition and the molding of the obtained composition. Further, when a compound having a flow temperature of more than 450 ° C. is added, the polyester and the molten liquid crystalline polyester are not dispersed during the production of the composition because the melt viscosity of the polyester is high, which is not preferable. The blending amount of the polyester (C) having a specific structure used in the present invention is 100 parts by weight of the total amount of the molten liquid crystalline polyester (A), the molten liquid crystalline polyester (B) and the polyester (C) having the specific structure. 1 to 99 parts by weight. When the amount is less than 1% by weight, the anisotropy of the molded product is not sufficiently improved. If the amount is more than 99% by weight, the properties of the molten liquid crystalline polyester are greatly impaired, which is not preferable. The preferred amount is 3 to 70% by weight, more preferably 5 to 50% by weight.

[0011] The method for producing a molded article molded using the thermoplastic resin composition of the present invention is not particularly limited. Examples of a molding method for melting, shaping, and solidifying the resin include extrusion molding, injection molding, and blow molding, and among them, injection molding is particularly preferably used. The extruded molded article may be processed by cutting or pressing. Further, in the present invention, if necessary, fibrous or acicular reinforcing materials such as glass fibers, silica alumina fibers, alumina fibers, carbon fibers, and aluminum borate whiskers, and inorganic fillers such as talc, mica, clay, and glass beads. Materials, release additives such as fluororesins and metal soaps, coloring agents such as dyes and pigments, antioxidants, heat stabilizers, ultraviolet absorbers, antistatic agents, and ordinary additives such as surfactants. One or more can be added. Also, a small amount of thermoplastic resin, for example, polyethylene, polypropylene, polyvinyl chloride, ABS resin, polystyrene, methacrylic resin and a small amount of thermosetting resin, for example, phenolic resin,
Epoxy resin, cyanate resin, isocyanate resin,
One or more of a polyimide resin and a small amount of a rubber component can be added.

The means for compounding the raw materials for obtaining the resin composition of the present invention is not particularly limited. A molten liquid crystalline polyester, a polyester comprising the above structural units I, II and III, a reinforcing agent such as glass fiber, an inorganic filler, a release improver, a heat stabilizer, and the like, if necessary, using a Henschel mixer, a tumbler or the like. After mixing, the mixture is generally melt-kneaded using an extruder. As the melt-kneading method at that time, all the raw materials may be mixed at once and fed to an extruder, and if necessary, raw materials such as reinforcing materials such as glass fibers and inorganic fillers may be mixed with resin. It may be fed separately from raw materials mainly composed of.
The thermoplastic resin composition of the present invention can be suitably used for parts such as automobiles and aircraft, industrial equipment, home electric appliances, OA equipment, electric and electronic parts, and the like.

[0013]

EXAMPLES Examples of the present invention will be shown below, but the present invention is not limited to these examples. The measurements of tensile strength, yield elongation, flexural modulus, Izod impact value, molding shrinkage, and flow temperature in the examples were performed by the following methods. (1) Tensile strength and yield elongation: ASTM No. 4 dumbbell test pieces were molded from a thermoplastic resin molding material using an injection molding machine and measured in accordance with ASTM D638. (2) Flexural modulus: A test piece having a length of 127 mm, a width of 12.7 mm and a thickness of 6.4 mm was molded from a thermoplastic resin molding material using an injection molding machine, and measured in accordance with ASTM D790. (3) Anisotropy ratio 64 m from thermoplastic resin molding material using an injection molding machine
A test piece having an m square and a thickness of 3 mm was formed. The shrinkage in the direction perpendicular to and parallel to the flow of the resin during molding was measured, and (shrinkage in the perpendicular direction / shrinkage in the equilibrium direction) was calculated to obtain the anisotropy ratio. The closer this value is to 1, the smaller the anisotropy. (4) Solder heat resistance JIS from thermoplastic resin molding material using an injection molding machine
K7113 (1/2) dumbbell test piece (thickness 1.2
mm) was molded, and the test piece was immersed in a solder bath heated to a predetermined temperature for 60 seconds, and then the appearance of the test piece was visually observed for swelling or deformation. The test was performed while raising the temperature of the solder bath by 5 ° C. in increments of 5 ° C. The temperature at which a change in appearance occurred, −5 ° C., was taken as the solder heat resistant temperature. (5) Thin-wall fluidity A sample was molded at a predetermined measurement temperature using an injection molding machine using a thin-wall fluid length measuring mold having four cavities each having a product part thickness of 0.2 mm shown in FIG. 1 (injection speed 95). %, Injection pressure 9
00 kg / cm ² ). The lengths of the four cavities of the removed molded article were measured, and the average value was defined as the thin-wall flow length.

REFERENCE EXAMPLE 1 Parahydroxybenzoic acid, 4,4'-dihydroxydiphenylsulfone and terephthalic acid were charged in a polymerization tank having an irrigated stirring blade in a molar ratio of 60:30:30. To this was added 1.1 times equivalent of acetic anhydride with respect to the hydroxy group, and the mixture was stirred for 10 minutes while replacing the inside of the system with nitrogen. Thereafter, the reaction temperature was raised to 150 ° C. while stirring under a nitrogen atmosphere,
After performing the acetylation reaction for one hour, the temperature was raised to 320 ° C. at a rate of 1 ° C./min while distilling off acetic acid produced as a by-product.
Polycondensation was performed at 0 ° C. for 15 minutes. The obtained polymer was taken out of the polymerization tank, cooled, and then pulverized (Rothoplex R16 / 8, manufactured by Hosokawa Micron Corp.) with an average particle size of 1
mm or less, and 230 under normal pressure nitrogen atmosphere.
The solid phase polymerization was carried out for 4 hours at a processing temperature of
(P1) was obtained. The flow temperature of this polyester is 315
° C.

Reference Example 2 Parahydroxybenzoic acid, 4,4'-dihydroxydiphenylsulfone, terephthalic acid and isophthalic acid were used in the following manner:
A polymer was obtained in the same manner as in Reference Example 1, except that the mixture was charged at a molar ratio of 40:30:10. After taking out the obtained polymer from the polymerization tank and cooling it, particles having an average particle diameter of 1 mm or less were obtained by a pulverizer, and further subjected to solid-state polymerization at a processing temperature of 220 ° C. for 4 hours under a normal pressure nitrogen atmosphere to obtain polyester 2 ( P2) was obtained. The flow temperature of this polyester was 315 ° C.

Examples 1 to 4 and Comparative Examples 1 to 4 As the molten liquid crystalline polyester (A), the repeating structural units consist of the above-mentioned IV, V, VI and VII.
A VI: VII molar ratio of 60: 20: 15: 5 and a flow temperature of 323 ° C., and a molten liquid crystalline polyester (B) having an IV: V: VI: VII molar ratio of 60:20.
20:10:10, the flow temperature of 280 ° C., the polyester polymerized in Reference Example 1 or 2, and glass fiber (trade name: CS03J, manufactured by Asahi Fiber Glass Co., Ltd.)
APx-1) in a composition ratio shown in Table 1 using a Henschel mixer, followed by a twin-screw extruder (PCM-3 manufactured by Ikegai Iron Works Co., Ltd.).
Using 0), the mixture was granulated at a cylinder temperature of 340 ° C. to obtain thermoplastic resin compositions (Examples 1 to 4 and Comparative Examples 1 to 3). The thermoplastic resin composition was subjected to injection molding at a cylinder temperature of 350 ° C. and a mold temperature of 130 ° C. using an injection molding machine (PS40E5ASE manufactured by Nissei Resin Industry Co., Ltd.), and the above-mentioned (1) to
A test piece was molded as in (4), and the tensile strength, flexural modulus, anisotropy ratio, and solder heat resistance temperature were measured. In addition, an injection molding machine (PS1 manufactured by Nissei Plastic Industry Co., Ltd.)
(0E1ASE type) at a cylinder temperature of 350 ° C. and a mold temperature of 130 ° C., and the thin-wall flow length was measured by the method (5) described above.

[0017]

[Table 1]

[0018]

Industrial Applicability The thermoplastic resin composition of the present invention has high strength, excellent thin-wall fluidity, and excellent heat resistance.
It is extremely useful for applications such as A equipment, electric and electronic parts.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a mold for measuring a thin flow length.

Claims (4)

[Claims] 1. The flow temperature defined below is from 310 ° C. to 4 ° C.
Contains, as essential components, a molten liquid crystalline polyester (A) having a temperature of 00 ° C., a molten liquid crystalline polyester (B) having a flow temperature defined below of 270 ° C. to 370 ° C., and a polyester (C) defined below. (A) and (B)
The flow temperature difference between (A) and (B) is 10 to 60 ° C.
(A) 1 to 99 parts by weight per 100 parts by weight of (B)
A thermoplastic resin composition comprising 99 to 1 part by weight, and containing 1 to 99 parts by weight of (C) per 100 parts by weight of the total of (A), (B) and (C). . Flow temperature: When using a capillary rheometer having a nozzle with an inner diameter of 1 mm and a length of 10 mm and extruding the heated melt from the nozzle at a rate of 4 ° C./min under a load of 100 kg / cm ² , the melt viscosity is Temperature indicating 48000 poise. Polyester (C): (Wherein, X is _{-SO 2 -, - CO -,} - O -, - S-,
_{-CH 2 -, - CH 2 -CH} 2 -, - C (CH 3) 2 - and it is one or more selected from a single bond, R ₁ is an alkyl group having 1 to 6 carbon atoms , Carbon number 3-10
Represents an alkenyl group, a phenyl group or a halogen atom, p is an integer of 0 to 4, m and n are integers of 1 to 4. A plurality of each R ₁ on the same or different nuclei may be different from each other. Further, each p may be different from each other. ) Of the formula: 0 ≦ (I) ≦ 95 (mol%) (II) + (III) = 100− (I) (mol%) and 0.9 ≦ (II) ) / (III) Polyester having a relationship satisfying ≦ 1.1. 2. A repeating unit II of the polyester (C), X is -SO ₂ - and / or -C (CH _{3) 2} -
The thermoplastic resin composition according to claim 1, which is: 3. The molten liquid crystalline polyesters (A) and (B) have the following structural units (IV), (V),
(VI) and (VII), each having V / IV
Is 0.2 to 1.0, the molar ratio of (III + IV) / V is 0.9 to 1.1, and the molar ratio of VII / V is 0.
VII of the liquid crystalline polyester (A)
/ V molar ratio (α) and VII / VI molar ratio (β) of the molten liquid crystalline polyester (B), and the molar ratio (α) / molar ratio (β) is 0.1 to 0.5. The resin composition according to claim 1, wherein Embedded image 4. A molded article molded using the thermoplastic resin composition according to claim 1, 2 or 3.