JP3358314B2 - Thermoplastic resin composition - Google Patents

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 containing liquid crystal polyester and aromatic polycarbonate, a specific glass fiber and an inorganic filler as main components.

[0002]

2. Description of the Related Art Aromatic polycarbonate is a resin excellent in impact resistance and the like, but is an amorphous resin and has a problem that the resin is largely deformed near a glass transition temperature (150 ° C.).

On the other hand, liquid crystal polyesters are different from crystalline polyesters such as polyethylene terephthalate and polybutylene terephthalate, and do not entangle even in a molten state because molecules are rigid, form polydomains having a liquid crystal state, and have low shear. Shows a behavior in which molecular chains are remarkably oriented in the flow direction, and is generally called a molten liquid crystal (thermotropic liquid crystal) polymer. Due to this unique behavior, the melt fluidity is extremely excellent, and 0.2 to 0.5 m
A thin molded product having a thickness of about m can be easily obtained, and this molded product has the advantage of exhibiting high strength and high rigidity.

However, there is a disadvantage that the anisotropy is extremely large and the weld strength is extremely low. In addition, applications are limited due to high molding temperature. Another problem is that liquid crystal polyesters are generally expensive.

Conventionally, as an attempt to solve such disadvantages of the aromatic polycarbonate and the liquid crystal polyester, there has been an attempt to complement the physical properties of the aromatic polycarbonate and the liquid crystal polyester with a composition obtained by melt-kneading the two. For example, although disclosed in Japanese Patent Publication No. 1-60057, Japanese Patent Application Laid-Open No. H4-225054, and Japanese Patent Application Laid-Open No. H2-102257, none of the compositions has developed sufficient physical properties.

JP-A-5-86266 and JP-A-5-86267 disclose a composition obtained by adding an epoxy compound to a liquid crystal polyester or a thermoplastic resin. Is not sufficient, and it is not always easy to obtain a composition obtained by adding a compound to a resin, since a compound that does not contribute to the reaction may remain in the composition and deteriorate the physical properties of the composition.

[0007]

DISCLOSURE OF THE INVENTION The present invention is intended to reduce the amount of glass fibers and inorganic fillers while maintaining the excellent impact resistance of an aromatic polycarbonate and utilizing the high rigidity and heat resistance of a liquid crystal polyester. It is intended to provide a low-priced resin composition by adding the molded article to reduce the molding shrinkage and improve the rigidity.

[0008]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve these problems, and have reached the present invention. That is, the present invention is the following invention.

(1) (A) a liquid crystal polyester, (B) an aromatic polycarbonate, (C) a number average fiber diameter of 5 to 25.
μm, the number average fiber length is 30 to 1000 μm, the number average fiber length / number average fiber diameter is 2 to 150, and the surface-untreated glass fiber and (D) the number average particle diameter are 0.05 to 10 μm.
m), and the liquid crystal polyester of the component (A) has a repeating unit (a) of 30 to
80 mol%, repeating unit (b) is 0 to 10 mol%, repeating unit (c) is 10 to 25 mol%, repeating unit (d) is 10 to 35 mol%, and repeating unit (e) is 0 to 0 mol%.
The aromatic polycarbonate of component (B) has an Fe content of 1 ppm or less and a Cl content of 50 pp.
m or less, and the composition ratio of component (A) to component (B) is such that component (A) is 1 to 30% by weight, component (B) is 99 to 70% by weight, and component (A) A thermoplastic resin composition comprising the component (C) in an amount of 1 to 50 parts by weight and the component (D) in an amount of 1 to 100 parts by weight based on 100 parts by weight of the total amount of the component (B).

Embedded image (In the formula, Ar is a divalent aromatic group.)

(2) The thermoplastic resin composition according to (1), wherein the inorganic filler of component (D) is talc and / or calcium carbonate.

(3) The liquid crystal polyester resin composition according to (1), wherein the liquid crystal polyester of the component (A) has a flow temperature defined below in the range of 240 to 360 ° C. Flow temperature: Resin heated at a heating rate of 4 ° C./min.
Temperature at which the melt viscosity shows 48,000 poise when measured by a method of extruding from a nozzle having an inner diameter of 1 mm and a length of 10 mm under kgf / cm ² . (4) The thermoplastic resin composition according to (1), wherein the component (A) and the component (C) are mainly dispersed in a matrix of the component (B).

Hereinafter, the present invention will be described in detail. The liquid crystal polyester of the component (A) in the present invention contains 30 to 80 mol% of the repeating structural unit (a),
10 mol%, (c) 10 to 25 mol%, (d) 10 to 3
An aromatic polyester comprising 5 mol% and (e) 0 to 40 mol%. The repeating structural unit (d) is derived from a divalent aromatic diol, and specifically includes the following repeating structural units.

[0013]

Embedded image

[0014]

Embedded image Among these, (C ₁ ), (C ₂ ) and (C ₃ ) are preferred, and (C ₁ ) is particularly preferred.

The liquid crystal polyester of the component (A) according to the present invention is obtained by adding a resin heated at a flow rate of 4 ° C./min under a load of 100 kgf / cm ² to an inner diameter of 1 mm.
When measured by a method of extruding from a 10 mm long nozzle, the melt viscosity is 48,000 poise (temperature at which the melt viscosity is 48000 poise).
Those having a temperature range of -360 ° C are preferably used. More preferably, it is in the range of 250 to 340 ° C. If the flow temperature of the liquid crystal polyester of the component (A) exceeds 360 ° C., it is necessary to increase the set temperature at the time of melt-kneading the composition, and in that case, the aromatic polycarbonate of the component (B) may decompose. Not preferred. If the flow temperature of the component (A) is lower than 240 ° C., the heat resistance of the composition is remarkably reduced, which is not preferable.

Component (B) of the thermoplastic resin composition of the present invention
Is an aromatic polycarbonate having a repeating structural unit represented by the general formula (VI) obtained by reacting a dihydric phenol with a carbonate precursor such as phosgene, a haloformate, and a carbonate. Fe content in polycarbonate is 1p
pm or less, Cl content is 50 ppm or less, preferably 10 ppm or less.
ppm or less.

If the Fe content and the Cl content are out of either of the above ranges, decomposition or foaming of the resin may occur during heating, which is not preferable. Fe content in resin, Cl
The content can be determined by an ordinary analytical method such as an atomic absorption method or a fluorescent X-ray method.

Embedded image (In the formula, A is a divalent aromatic group derived from a dihydric phenol.)

The dihydric phenol used here is:
It is a monocyclic or polycyclic aromatic compound having two hydroxyl groups directly bonded to carbon in an aromatic ring. Specific examples of these dihydric phenols include 2,2-bis (4-hydroxyphenyl) propane (bisphenol A), hydroquinone, resorcin, 2,2-bis (hydroxyphenyl) pentane, and 2,4'-dihydroxy-diphenylmethane Bis (2-hydroxyphenyl) methane, bis (4-hydroxyphenyl) methane, bis (4-hydroxy-5-nitrophenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 3,3-bis (4
{Hydroxyphenyl) pentane, 2,2-dihydroxydiphenyl, 2,6-dihydroxynaphthalene, bis (4-hydroxyphenyl) sulfone, 2,4'dihydroxydiphenylsulfone, 5-chloro-2,4 '
{Dihydroxydiphenylsulfone, bis (4-hydroxyphenyl) diphenyldisulfone, 4,4} dihydroxydiphenylether, 4,4 ′ {dihydroxy}
3,3′─dichlorodiphenyl ether, 4,4′─dihydroxy─2,5─diethoxydiphenyl ether and the like. Preferably, bisphenol A and its nuclear-substituted derivatives are mentioned. These dihydric phenols are used alone or in combination.

The aromatic polycarbonate used in the resin composition of the present invention is produced by a known method using the above-mentioned dihydric phenol as a raw material, that is, a transesterification method, a solution method, an interfacial polycondensation method and the like. Molecular weight 1
It is 5000 or more, more preferably 25000 or more. These specific polymerization methods are described, for example, in "ENC
YCLOPEDIA OF POLYMER SCIE
NCE AND TECHNOLOGY "Vol. 10 (J
hon Wiley & Sons, Inc. , 196
9)), "Polycarbonate" on pages 710-764. As these polycarbonates, copolymers exemplified by polycarbonate / styrene block copolymers disclosed in JP-B-48-25076 can also be used.

Component (C) of the thermoplastic resin composition of the present invention
The glass fiber has a number average fiber diameter of 5 to 25 μm, preferably 5 to 20 μm, and a number average fiber length of 30 to 1000 μm.
m, preferably 30 to 300 μm. If the number average fiber diameter or number average fiber length is out of this range, the reinforcing effect of the glass fiber becomes small, and sufficient rigidity, dimensional stability or workability cannot be obtained, which is not preferable.

Further, the form ratio (hereinafter sometimes referred to as an aspect ratio) represented by the number average fiber length / number average fiber diameter of the glass fibers, that is, the ratio of the number average fiber length to the number average fiber diameter of the glass fibers. Number average is 2-150, preferably 3
Glass fibers of up to 20 are used. If the number average aspect ratio is out of this range, the appearance of a molded article of the composition is poor and the moldability is poor, which is not preferable. The glass fiber of the component (C) in the present invention has no surface treatment. The use of other glass fibers is not preferred because the mechanical properties and heat resistance of the composition decrease.

The inorganic filler of the component (D) in the present invention includes calcium carbonate, talc, clay, silica, magnesium carbonate, barium sulfate, titanium oxide, alumina, gypsum, etc., which are commonly used except for glass fibers. Talc and calcium carbonate are preferably used, and talc is more preferably used. The number average particle diameter of the inorganic filler is preferably 0.05 to 10 μm. If the number average particle diameter is less than 0.05 μm, the effect of improving the shrinkage and rigidity of the molded article will be small, and if it exceeds 10 μm, the surface gloss of the molded article will be significantly impaired, which is not preferable.

In the thermoplastic resin composition of the present invention,
Component (A), component (B), component (C) and component (D)
By taking the composition ratio within a specific range, an intended thermoplastic resin composition can be obtained. In the present invention, the composition ratio of component (A) to component (B) is 1 to 30% by weight for component (A), 99 to 70% by weight for component (B), and preferably 2 to 25% for component (A). % By weight, and the component (B) is 98 to 75% by weight. When the component (A) is less than 1% by weight, heat resistance of a molded article comprising the composition,
If the mechanical properties are insufficient, and if it exceeds 30% by weight, the dimensional stability of the composition will be insufficient, and the cost will be less advantageous, which is not preferable.

In the present invention, the component (C) is used in an amount of 1 to 50 parts by weight, preferably 2 to 40 parts by weight, based on 100 parts by weight of the total of the components (A) and (B). ) Is from 1 to 100 parts by weight, preferably from 2 to 40 parts by weight.
Parts by weight. When the component (C) is less than 1 part by weight or the component (D) is less than 1 part by weight, the effect of improving the mechanical strength and shrinkage of the thermoplastic resin composition of the present invention is small,
On the other hand, when the component (C) exceeds 50 parts by weight or the component (D) exceeds 100 parts by weight, the molding processability of the composition is deteriorated, and the appearance of the injection-molded article is unfavorably deteriorated.

In a preferred embodiment of the thermoplastic resin composition of the present invention, the liquid crystalline polyester of the component (A) and the specific glass fiber of the component (C) are mainly continuous in the matrix of the aromatic polycarbonate of the component (B). And the component (D) is finely dispersed. In the case of such a form, the mechanical properties of the composition are particularly excellent.

The method for producing the thermoplastic resin composition of the present invention is not particularly limited, and a known method can be used. For example, a method in which a resin component in a solution state is mixed with glass fiber and an inorganic filler and the solvent is evaporated, or a method in which the resin component, the glass fiber and the inorganic filler are precipitated in the solvent, is mentioned. From an industrial point of view, a method of kneading each component in a molten state is preferred. For the melt kneading, kneading apparatuses such as a single-screw or twin-screw extruder and various kneaders which are generally used can be used. In particular, a biaxial high kneader is preferred. During the melt kneading, the cylinder set temperature of the kneading device is preferably in the range of 200 to 360 ° C,
More preferably, it is 250 to 340 ° C.

At the time of kneading, the respective components may be previously mixed uniformly using a device such as a tumbler or a Henschel mixer. If necessary, the mixing may be omitted, and the components may be separately supplied to the kneading device. Methods can also be used.

For example, a liquid crystal polyester and an aromatic polycarbonate are previously solution-blended or melt-kneaded to obtain a mixture, which is then melt-kneaded with a glass fiber and an inorganic filler to obtain a thermoplastic resin composition. it can. In addition, aromatic polycarbonate and liquid crystal polyester are charged from the first input port of the kneading machine, and liquid crystal polyester or aromatic polycarbonate, glass fiber and inorganic filler are charged from the second input port, and the thermoplastic resin is kneaded once. A composition can also be obtained.

Further, a liquid crystal polyester and an aromatic polycarbonate are melt-kneaded, and the kneaded product is blended with a liquid crystal polyester, an aromatic polycarbonate, glass fiber and an inorganic filler, and further melt-kneaded to obtain a thermoplastic resin composition. You can also get.

The kneaded resin composition is molded by injection molding, extrusion molding, or other various molding methods, but is not subjected to a kneading process in advance, but is dry-blended at the time of injection molding or extrusion molding to perform a melt processing operation. The resin composition of the present invention can be kneaded into the resin composition to directly obtain a molded product.

The thermoplastic resin composition of the present invention may further contain, if necessary, an organic filler, an antioxidant, a heat stabilizer, a light stabilizer, a flame retardant, a lubricant, an antistatic agent, an inorganic or organic coloring. Various additives such as a rust preventive, a cross-linking agent, a foaming agent, a fluorescent agent, a surface smoothing agent, a surface gloss improving agent, and a mold release improving agent such as a fluororesin are added in a manufacturing process or a subsequent processing process. be able to.

[0032]

EXAMPLES The present invention will be described below with reference to examples, but these are merely examples, and the present invention is not limited to these examples. (1) Liquid Crystal Polyester of Component (A) The liquid crystal polyester used as the component (A) is as follows.

(I) p-acetoxybenzoic acid 10.8k
g (60 mol), 2.49 kg (15 mol) of terephthalic acid, 0.83 kg (5 mol) of isophthalic acid and 4,
5.45 kg of 4'-diacetoxydiphenyl (20.2
Mol) was charged into a polymerization tank having a comb-shaped stirring blade, and the temperature was increased while stirring under a nitrogen gas atmosphere, and polymerization was performed at 330 ° C. for 1 hour. During this time, the polymerization was carried out under vigorous stirring while removing acetic acid produced as a by-product. After that, the system was gradually cooled,
Was taken out of the system. The obtained polymer was pulverized with a hammer mill manufactured by Hosokawa Micron Co., Ltd. to obtain particles having a diameter of 2.5 mm or less. This was further treated in a rotary kiln under a nitrogen gas atmosphere at 280 ° C. for 3 hours to obtain a particulate wholly aromatic polyester having a flow temperature of 324 ° C. and comprising the following repeating structural units. Hereinafter, the liquid crystal polyester is abbreviated as A-1. This polymer showed optical anisotropy at 341 ° C. under pressure.
The repeating structural units of the liquid crystal polyester A-1 are as follows.

[0034]

Embedded image

(Ii) p-hydroxybenzoic acid 16.6
kg (12.1 mol), 8.4 kg (4.5 mol) of 6-hydroxy-2-naphthoic acid and 18.6 k of acetic anhydride
g (18.2 mol) was charged into a polymerization tank equipped with a comb-shaped stirring blade, and the temperature was increased while stirring under a nitrogen gas atmosphere.
For 1 hour and then under a reduced pressure of 2.0 torr for 32 hours.
Polymerization was performed at 0 ° C. for 1 hour. During this time, acetic acid produced as a by-product was continuously distilled out of the system. Thereafter, the system was gradually cooled to 180
The polymer obtained at ℃ was taken out of the system. The obtained polymer is pulverized in the same manner as in the above (i), and then treated in a rotary kiln under a nitrogen gas atmosphere at 240 ° C. for 5 hours to obtain a particulate repeating unit having a flow temperature of 270 ° C. Was obtained. Hereinafter, the liquid crystal polyester is abbreviated as A-2. This polymer showed optical anisotropy at 280 ° C. or more under pressure. The ratio of the repeating structural units of the liquid crystal polyester A-2 is as follows.

[0036]

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(2) Aromatic polycarbonate of component (B) The aromatic polycarbonate used as component (B) is as follows. b-1 (abbreviation): CALIBRE manufactured by Sumitomo Dow
(Registered trademark) 200-3 [Fe content <1 ppm, Cl content = 1 ppm, MFR (300 ° C., 1.2 kg load) =
3]. b-2 (abbreviation): CALIBRE manufactured by Sumitomo Dow
(Registered trademark) 300-10 [Fe content <1 ppm, Cl
Content = 2 ppm, MFR (300 ° C., 1.2 kg load)
= 10].

(3) Glass Fiber of Component (C) The glass fibers used as component (C) in the thermoplastic resin composition of the present invention are as follows. The diamine used as component (C) is as follows. C-1 (abbreviation): EFH75 manufactured by Central Glass Co., Ltd.
-01 (trade name), number average fiber diameter 13 μm, number average fiber length 50 μm, aspect ratio 3.8, no surface treatment. C-2 (abbreviation): REV8 (trade name) manufactured by Nippon Sheet Glass Co., Ltd., number average fiber diameter 13 μm, number average fiber length 70 μm,
Aminosilane treatment with an aspect ratio of 5.4.

(4) Inorganic Filler of Component (D) Table 1 shows the types, number average particle diameters and abbreviations of the inorganic fillers used as component (D). In addition, the number average particle diameter was obtained by performing a scanning electron microscope observation after performing gold deposition on the inorganic filler and measuring the particle diameter of several hundred particles. Similarly, the number average thickness of talc was determined.

[Table 1]

(Measurement of physical properties) Flexural modulus: ASTM for a test piece (3.2 mm thick)
It was measured according to D790. Tensile properties: ASTM No. 4 dumbbell test piece was molded and subjected to AS
The elongation and the strength at break were measured according to TM D638. Molding shrinkage: The dimensions of the injection molded article in the flow direction (MD) and the direction perpendicular to the flow (TD) were measured and determined as a ratio to the original mold size. The anisotropy ratio of the molding shrinkage was determined as the ratio (TD / MD) between the shrinkage in the TD direction and the shrinkage in the MD direction.

(Morphological Observation) A small piece of the molded article was placed in carbon tetrachloride, allowed to stand at room temperature overnight, and the suspended matter in the carbon tetrachloride at the time of stirring was taken out and dried. After vapor deposition, scanning electron microscope observation was performed. The form was performed as follows. A: Component (A) and component (C) are mainly continuous. B: The component (A) is mainly continuous.

Examples 1 to 3 and Comparative Examples 1 to 6 Each component was mixed with a stabilizer in the composition shown in Table 1 with a Henschel mixer, and then mixed with a cylinder using a PCM-30 twin screw extruder manufactured by Ikegai Iron Works Co., Ltd. Set temperature 290-334 ° C
The mixture was kneaded while devolatilizing at a molding temperature of 2 using a PS40E5ASE type injection molding machine manufactured by Nissei Plastic Industry Co., Ltd.
Physical properties were measured and morphological observations were carried out on the molded product obtained by injection molding at 90 to 334 ° C and a mold temperature of 80 to 100 ° C as described above. Tables 2 and 3 show the obtained results. It can be seen that the thermoplastic resin composition of the present invention has excellent mechanical properties, particularly excellent flexural modulus, good molding shrinkage, and low cost.

[0043]

[Table 2]

[0044]

[Table 3]

[0045]

The thermoplastic resin composition of the present invention retains the excellent impact resistance of the aromatic polycarbonate, the high rigidity and the heat resistance of the liquid crystal polyester, and a small amount of glass fiber and inorganic filler. The addition of the material reduces the molding shrinkage of the molded product, improves rigidity, and is an inexpensive resin composition. The thermoplastic resin composition is a molded product by injection molding or extrusion molding utilizing such properties,
Used for sheets, tubes, fibers, laminates, coating materials and the like.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C08L 67/00 C08L 69/00

Claims (4)

(57) [Claims] (A) a liquid crystal polyester, (B) an aromatic polycarbonate, (C) a number average fiber diameter of 5 to 25 μm,
A number average fiber length of 30 to 1000 μm, a number average fiber length / number average fiber diameter of 2 to 150, surface-untreated glass fiber and (D) an inorganic filler having a number average particle diameter of 0.05 to 10 μm. The liquid crystal polyester of the component (A) contains 30 to 80 mol% of the following repeating unit (a), 0 to 10 mol% of the repeating unit (b), and 10 to 25 of the repeating unit (c). Mol%, the repeating unit (d) is 10 to 35 mol%, the repeating unit (e) is 0 to 40 mol%, and the aromatic polycarbonate of the component (B) is
Fe content is 1 ppm or less, Cl content is 50 ppm or less, and the composition ratio of component (A) to component (B) is such that component (A) is 1 to 30% by weight and component (B) is 99 to 7% by weight.
0% by weight, and the total amount of the components (A) and (B) is 10
Component (C) is 1 to 50 parts by weight with respect to 0 parts by weight,
A thermoplastic resin composition in which the component (D) is 1 to 100 parts by weight. Embedded image (In the formula, Ar is a divalent aromatic group.) 2. The method according to claim 1, wherein the inorganic filler of component (D) is talc and / or talc.
Or calcium carbonate.
The thermoplastic resin composition according to the above. 3. The liquid crystal polyester resin composition according to claim 1, wherein the liquid crystal polyester of the component (A) has a flow temperature as defined below in the range of 240 to 360 ° C. Flow temperature: Resin heated at a temperature rising rate of 4 ° C./min, under a load of 100 kgf / cm ² , having an inner diameter of 1 mm and a length of 10
The temperature at which the melt viscosity indicates 48,000 poise when measured by a method of extruding through a nozzle of mm. 4. Component (A) in a matrix of component (B)
The thermoplastic resin composition according to claim 1, wherein the component (C) and the component (C) are mainly dispersed continuously.