JP2000302962A - Polycarbonate resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition improved in slidability without impairing its mechanical strength and excellent in molded product appearance by including a polycarbonate resin, a copolycarbonate resin and a silicone oil in specified proportions. SOLUTION: This composition is obtained by including 100 pts.wt. of a blend of (A) 0-99 pts.wt. of a polycarbonate resin and (B) 1-100 pts.wt. of a copolycarbonate resin composed of constitutive units of respective formulas I and II [n is 1-200; R is a 2-6C alkylene; XI to X4 are each a 1-20C hydrocarbon or halocarbon; B is a 1-10C alkylidene, aryl-substituted alkylene), O, S, CO or the like; R1 to R4 are each H, a halogen or 1-4C alkyl] and (C) 0.1-5 pts.wt. of a silicone oil with a viscosity (25 deg.C) of >=10,000 mm2/s, pref. >=100,000 mm2/s, more pref. >=1000,000 mm2/s; wherein the constitutive unit of formula I accounts for pref. 0.2-50 wt.% of the total constitutive units.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polycarbonate resin composition having excellent slidability without impairing the inherent properties of the polycarbonate resin such as mechanical strength and heat resistance.

[0002]

2. Description of the Related Art In recent years, synthetic resins have been increasingly used for sliding members for the purpose of reducing the size and weight of OA equipment and electronic equipment and reducing the number of parts. It is used for parts of sliding members such as gears because of its mechanical strength. However, since the polycarbonate resin is originally a resin having poor sliding properties,
For the purpose of improvement, a sliding agent has been added.
For example, Japanese Unexamined Patent Application Publication No.
No. 136065 describes that a resin such as a fluororesin, polyolefin, polyamide, or polyester is added to a polycarbonate resin as a slidability improving material. However, when a fluorine resin is added to a polycarbonate resin, a small amount of fluorine gas is generated at the time of molding, which causes problems such as corrosion of a mold and a molding machine, and a large amount of a fluorine resin having no affinity needs to be added. Also, problems such as delamination and mold deposit during molding have occurred. Also, if you add a large amount of other thermoplastic resins such as polyolefin, polyamide, polyester,
In addition to impairing the inherent properties of polycarbonate resin such as mechanical strength, heat resistance, and flame retardancy,
Problems such as delamination also occur.

[0003] On the other hand, polycarbonate resin is chemically,
Silicone oil, which is a physically stable lubricant, is also added, but the silicone oil on the surface of the molded product is exuded in a short time and is consumed. However, long-term slidability was insufficient, and there were problems such as sticky surfaces, which were not satisfactory. Therefore, further attempts have been made to use high molecular weight silicone oils. In this case, although the bleed-out of the oil to the molded product and the long-term slidability have been improved, it is not always satisfactory. I have to add a large amount,
As a result, gloss unevenness and the like due to phase separation of the silicone oil were likely to occur on the surface of the molded product, which was not practically satisfactory. To improve this, for example,
Japanese Patent Application Laid-Open No. 9-255864 describes that the appearance is improved by adding another thermoplastic resin such as a polyolefin resin or a polystyrene resin to a composition comprising a polycarbonate resin and a high-viscosity silicone oil. However, the improvement effect was not enough.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a polycarbonate resin composition which has improved slidability and excellent appearance of molded articles without impairing the mechanical strength and heat resistance inherent to the polycarbonate resin. It is intended for.

[0005]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve the above-mentioned problems, and as a result, a resin composition obtained by blending a high-viscosity silicone oil with a polycarbonate resin has a specific structure. By blending a copolycarbonate resin with mechanical strength, heat resistance,
The present inventors have found that a resin composition having excellent slidability and appearance of a molded product can be obtained, and have reached the present invention. That is, the present invention provides 0 to 99 parts by weight of a polycarbonate resin (A), 1 to 100 parts by weight of a copolycarbonate resin (B) having a structural unit represented by the following structural formulas (1) and (2), and 25
0.1 to 5 parts by weight of a silicone oil (C) having a viscosity at 10,000 ° C. of 10,000 mm ² / s or more, and the total of the polycarbonate resin (A) and the copolycarbonate resin (B) is The purpose of the present invention is to provide 100 parts by weight of a polycarbonate resin composition. Structural formula (1)

[0006]

Embedded image

Structural formula (2)

[0008]

Embedded image

(In the structural formula (1), n represents an integer of 1 to 200; R represents an alkylene group having 2 to 6 carbon atoms;
1, X2, X3 and X4 each independently represent a hydrocarbon group having 1 to 20 carbon atoms or a halogenated hydrocarbon group. In the structural formula (2), B represents a linear, branched or cyclic alkylidene group having 1 to 10 carbon atoms, an aryl-substituted alkylene group, an aryl group, or —O—, —S—, —CO—, —SO — Or —SO ₂ —, and R1, R2, R3 and R4 independently represent hydrogen, halogen or an alkyl group having 1 to 4 carbon atoms. )

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
In the present invention, an aromatic polycarbonate, an aliphatic polycarbonate, or an aromatic-aliphatic polycarbonate can be used as the polycarbonate resin (A), but an aromatic polycarbonate is preferable. As the aromatic polycarbonate resin in the present invention, an aromatic hydroxy compound or a small amount of a polyhydroxy compound and an optionally branched thermoplastic aromatic polycarbonate polymer or a copolymer prepared by reacting a small amount of the polyhydroxy compound with phosgene or a carbonic acid diester are used. It is a polymer. The production method is not limited, and it can be produced by a phosgene method (interfacial polymerization method) or a melting method (ester exchange method). Further, an aromatic polycarbonate resin produced by a melting method and having an adjusted amount of terminal OH groups can be used.

The aromatic dihydroxy compound includes 2,2.
2-bis (4-hydroxyphenyl) propane (= bisphenol A), tetramethylbisphenol A, bis (4-hydroxyphenyl) -P-diisopropylidenebenzene, hydroquinone, resorcinol, 4,4-
Dihydroxydiphenyl and the like are preferable, and bisphenol A is preferable. Two or more of these dihydroxy compounds may be used in combination. Further, a compound in which one or more tetraalkylphosphonium sulfonates are bonded to the above-mentioned aromatic dihydroxy compound for the purpose of further increasing the flame retardancy can also be used. In order to obtain a branched aromatic polycarbonate resin, phloroglucin, 4,6-
Dimethyl-2,4,6-tri (4-hydroxyphenyl) heptene-2,4,6-dimethyl-2,4,6-tri (4-hydroxyphenyl) heptane, 2,6-dimethyl-2,4 6-tri (4-hydroxyphenyl) heptene-3, 1,3,5-tri (4-hydroxyphenyl) benzol, 1,1,1-tri (4-hydroxyphenyl) ethane, 2,6-bis (2 -Hydroxy-5-
Methylbenzyl) -4-methylphenol, α, α ′,
α "-tri (4-hydroxyphenyl) -1,3,5-
Polyhydroxy compounds such as triisopropylbenzene, or 3,3-bis (4-hydroxyphenyl) oxindole (= isatin bisphenol), 5-chlorisatin bisphenol, 5,7-dichloroisatin bisphenol, 5- Bromoisatin bisphenol or the like may be used as a part of the aromatic dihydroxy compound.
And preferably 0.1 to 2 mol%.

In order to control the molecular weight, a monovalent aromatic hydroxy compound may be used, and m- and p-methylphenol, m- and p-propylphenol, p-tert-
Butylphenol and p-long-chain alkyl-substituted phenols. In addition, polycarbonate resin (A)
Alternatively, two or more resins may be mixed and used. The copolycarbonate resin (B) used in the present invention has a constitutional unit of the structural formula (1) composed of bisphenol having a silicone chain and an aliphatic chain as a constitutional unit, and is characterized by having a conventional aromatic structure. In the method for producing a polycarbonate resin, the same method as the conventional interfacial polymerization method and melt polymerization method except that a dihydroxy compound having a silicone chain and a fatty chain represented by the following general formula (3) is used as a part of the aromatic dihydroxy compound. The manufacturing method is suitably applied. General formula (3)

[0013]

Embedded image

(In the formula, n, R, and X1 to X4 are the same as those in the structural formula (1).) The structural unit represented by the structural formula (1) in the copolycarbonate resin used in the present invention is not particularly limited. But preferably in the range of 0.2 to 50% by weight, especially 0.5 to 25% by weight.
A range of weight percent is preferred. When the amount of the structural unit represented by the structural formula (1) is less than 0.2% by weight, the effect of improving the compatibility between the polycarbonate resin and the silicone oil is small, and poor appearance is likely to occur. Is undesirably reduced. The repeating number (n) of the siloxane unit in the structural formula (1) is in the range of 1 to 200, preferably in the range of 5 to 100. Further, as R in the structural formula (1), ethylene, propylene, isopropylene,
Butylene, but pentylene, etc. hexylene are exemplified, especially -CHR5-CH ₂ - or -CH ₂ -CHR5-
(In the formula, R5 is bonded to a carbon atom on the benzene ring side, and represents hydrogen or a methyl group.).
X1 to X4 in the structural formula (1) are each independently a carbon exemplified by an alkyl group such as a methyl group, an ethyl group, a propyl group, and a butyl group, and an aryl group such as a phenyl group, a tolyl group, a xylyl group, and a naphthyl group. It represents a hydrocarbon group of the formulas 1 to 20, or a group in which at least one of hydrogen atoms bonded to carbon atoms of these groups is substituted with a halogen atom. The structural unit of the structural formula (1) is introduced by using a dihydric phenol having a phenolic hydroxyl group represented by the above general formula (3) at both terminals in the same manner as a normal bisphenol. The compound represented by the general formula (3) is obtained by converting a phenol having an olefinic unsaturated carbon-carbon bond, preferably vinylphenol or isopropenylphenol, to a polysiloxane chain having a predetermined degree of polymerization (n). At the end
It is easily produced by a hydrosilylation reaction.

In addition, polycarbonate resin (A),
Alternatively, the following aromatic dihydroxy compounds can also be used as a comonomer of the copolycarbonate resin (B). For example, bis (4-hydroxyphenyl) methane, bis (4-hydroxyphenyl) ether, bis (4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) sulfoxide, bis (4-hydroxyphenyl) sulfide, bis (4 -Hydroxyphenyl) ketone, 1,1-bis (4-hydroxyphenyl)
Ethane, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxyphenyl) butane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 2,2-bis (4-hydroxy -3,5-dibromophenyl) propane, 2,2-bis (4-hydroxy-3,5-dichlorophenyl) propane, 2,2-bis (4-hydroxy-3-bromophenyl) propane,
2,2-bis (4-hydroxy-3-chlorophenyl)
Examples include propane, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, and bis (4-hydroxyphenyl) diphenylmethane. . Of these, 2,2-bis (4-hydroxyphenyl) propane and 1,1-bis (4-hydroxyphenyl) cyclohexane are preferred from the viewpoint of thermal stability. In addition, a terminal terminator or a molecular weight regulator is usually used, and examples thereof include compounds having a monovalent phenolic hydroxyl group, and other compounds such as ordinary phenol, p-tert-butylphenol, and tribromophenol. Examples thereof include long-chain alkylphenols, aliphatic carboxylic acid chlorides, aliphatic carboxylic acids, hydroxybenzoic acid alkyl esters, hydroxyphenylcarboxylic acid alkyl esters, and alkyl ether phenols. The amount used is in the range of 100 to 0.5 mol, preferably 50 to 2 mol, based on 100 mol of all aromatic dihydroxy compounds used, and it is naturally possible to use two or more compounds in combination. is there.

Further, a branching agent is used in an amount of 0.01 to 3 mol%, particularly 0.1 to 1 mol%, based on the above aromatic dihydroxy compound.
A branched polycarbonate can be used in combination within the range of 1.0 mol%. Examples of the branching agent include phloroglucin, 4,6-dimethyl-2,4,6-tri (4-hydroxyphenyl) heptene-2,4,6-dimethyl-
2,4,6-tri (4-hydroxyphenyl) heptane, 2,6-dimethyl-2,4,6-tri (4-hydroxyphenyl) heptene-3,1,3,5-tri (4-
Hydroxyphenyl) benzol, 1,1,1-tri (4-hydroxyphenyl) ethane, 2,6-bis (2
Polyhydroxy compounds such as -hydroxy-5-methylbenzyl) -4-methylphenol, α, α ′, α ″ -tri (4-hydroxyphenyl) -1,3,5-triisopropylbenzene, or 3, 3-bis (4-hydroxyphenyl) oxindole (= isatin bisphenol), 5-chlorisatin bisphenol, 5,7-dichloroisatin bisphenol, 5-
Bromoisatin bisphenol is exemplified. The copolycarbonate resin (B) is used in an amount of 1 to 100 parts by weight based on 0 to 99 parts by weight of the polycarbonate resin (A), and it is necessary that the total of (A) and (B) be 100 parts by weight. The amount of (B) used is preferably 2 to 70 parts by weight, particularly preferably 5 to 50 parts by weight. If the use amount of the copolycarbonate resin is less than 1 part by weight, the effect of improving the compatibility between the polycarbonate resin and the silicone oil is small, and the appearance is liable to be poor.

The molecular weight of the polycarbonate resin including the copolycarbonate resin is a viscosity-average molecular weight calculated from solution viscosity measured at a temperature of 25 ° C. using methylene chloride as a solvent, and is in the range of 16,000 to 30,000. Preferably it is 17,000-25,000, More preferably, it is 18,000-23,000. If the viscosity average molecular weight is less than 16,000, the mechanical strength is insufficient, and if it exceeds 30,000, the appearance of a molded article is likely to be poor, which is not preferable. The silicone oil (C) used in the present invention has a viscosity of 10,000 mm at 25 ° C.
It is a silicone oil of ² / s or more and can be arbitrarily selected from commonly known ones. For example, those composed of polydimethylsiloxane, silicone oil in which some or all of the methyl groups of polydimethylsiloxane are substituted with phenyl groups, hydrogen, alkyl groups having 2 or more carbon atoms, halogenated phenyl groups, fluoroester groups, epoxy Epoxy-modified silicone oil having a group, amino-modified silicone oil having an amino group, alcohol-modified silicone oil having an alcoholic hydroxyl group, polyether-modified silicone oil having a polyether structure, and the like. Use in combination. The viscosity of the silicone oil (C) is preferably 100,000 mm ² / s or more, particularly preferably 1,000,000 mm ² / s or more. If the viscosity of the silicone oil is less than 10,000 mm ² / s, the long-term slidability is unsatisfactory.

In the polycarbonate resin composition of the present invention, when the total of the polycarbonate resin (A) and the copolycarbonate resin (B) is 100 parts by weight, the amount of the silicone oil (C) used is 0.1 to 5 parts by weight. , Preferably 0.2 to 3 parts by weight, particularly preferably 0.3 to 3 parts by weight.
2 parts by weight. When the amount of the silicone oil (C) exceeds 5 parts by weight, the mechanical strength, heat resistance and appearance of the molded product are unsatisfactory, and when the amount is less than 0.1 part by weight, the slidability is unsatisfactory. In addition, the resin composition of the present invention may contain, if necessary, additives such as ultraviolet absorbers, stabilizers such as antioxidants, pigments, dyes, lubricants, flame retardants, release agents, glass fibers, and glass flakes. A reinforcing material such as carbon fiber or a whisker such as potassium titanate or aluminum borate, or a resin other than a polycarbonate resin including a copolycarbonate resin can be added and blended. Among these, as resins other than polycarbonate resins including copolycarbonate resins, polybutylene terephthalate, polyester resins such as polyethylene terephthalate, polyamide resins,
A high impact polystyrene (HIPS) resin or a styrene resin such as an ABS resin, or a thermoplastic resin such as a polyolefin resin may be used. 4 of the total amount of resin other than polycarbonate resin including resin
0% by weight or less, more preferably 30% by weight or less.

As a method for obtaining the polycarbonate resin composition of the present invention, the above components are kneaded with various kneaders, for example, a uniaxial or multiaxial kneader, a Banbury mixer, a roll, a Brabender plastograph, or the like. A method of solidifying by cooling or a suitable solvent, for example, adding the above components to hydrocarbons such as hexane, heptane, benzene, toluene, xylene and derivatives thereof, and suspending the components to be dissolved or the components to be dissolved and the insoluble components to be suspended. For example, a solution mixing method of mixing in a state is used. From the industrial cost, the melt-kneading method is preferred, but not limited. The molding method used for the composition of the present invention is not particularly limited, and a molding method generally used for a thermoplastic resin composition, for example, injection molding, hollow molding, extrusion molding,
Molding methods such as sheet molding, thermoforming, rotational molding, and laminating can be applied.

[0020]

EXAMPLES The present invention will be described below with reference to Examples and Comparative Examples.
Although described in detail, the present invention is not limited in any way to these ranges. The following components were used as the components. [Reference Example-1] Production of copolycarbonate resin 3.7 kg of sodium hydroxide was dissolved in 42 L (liter) of water, and kept at 20 ° C, while maintaining 2,2-bis (4-hydroxyphenyl) propane (hereinafter “BPA”). Abbreviated as follows): 6,690 g, X1 to n1 = 50 in the general formula (3)
A compound in which X4 is a methyl group (hereinafter abbreviated as "165B"): 1,186 g, and 15 g of hydrosulfite were dissolved. To this, 30 L of methylene chloride was added, and while stirring, 148 g of pt-butylphenol was added, and then 3.5 kg of phosgene was blown in for 60 minutes. After the phosgene injection was completed, the reaction solution was vigorously stirred to emulsify the reaction solution. After emulsification, 8 mL (milliliter) of triethylamine was added, and stirring was continued for about 1 hour to carry out polymerization. After the polymerization liquid was separated into an aqueous phase and an organic phase, the organic phase was neutralized with phosphoric acid, and the water was washed repeatedly until the pH of the washing became neutral.
35 L of isopropanol was added to precipitate the polymer. The precipitate was filtered and then dried to obtain a white powdery copolycarbonate resin (hereinafter referred to as “C-PC1”).
5 ").

Reference Example 2 Production of Copolycarbonate Resin In Reference Example 1, BPA: 6,735 g, 165
B: A white powdery copolycarbonate resin (hereinafter abbreviated as “C-PC05”) was obtained in the same manner except that the amount was 356 g. (A) Polycarbonate resin: poly-4,4-isopropylidene diphenyl carbonate, product of Mitsubishi Engineering-Plastics Corporation, trade name: S3000, viscosity average molecular weight 21,000 (B) Silicone oil: B-1 polydimethylsiloxane Shin-Etsu Silicone Co., Ltd., product name: VRS-01, viscosity at 25 ° C .:
6,000,000 mm ² / s B-2 polydimethylsiloxane Shin-Etsu Silicone Co., Ltd. product name: KF-96, viscosity at 25 ° C .: 5
00mm ² / s

Example 1 After the components shown in Table 1 were uniformly mixed with a mixer, a twin-screw extruder (a product of Nippon Steel Works)
And pelletized at a cylinder temperature of 280 ° C. and a screw rotation speed of 250 rpm. Subsequently, the pellets and the remaining components were uniformly mixed by a mixer so as to have a predetermined ratio, and then pelletized at a cylinder temperature of 280 ° C. and a screw rotation speed of 250 rpm using the twin-screw extruder. Next, this resin composition was injection-molded using an injection molding machine (a product of Nippon Steel Works, clamping force: 55T) under the conditions of a cylinder temperature of 280 ° C and a mold temperature of 80 ° C to produce a molded product. The evaluation was performed by the following method.

[Evaluation method] Measurement of viscosity average molecular weight (1) Izod impact test A notched Izod impact test was performed in accordance with ASTM D256. (2) Flexural modulus A three-point bending test was performed according to a bending test method according to ASTM D790. (3) Heat deformation temperature According to ASTM D648, under the condition of 1.82 MPa,
A load deflection test was performed. (4) Repeated bending fatigue According to ASTM D671, using a Type A test piece,
The test was performed at 23 ° C. and an actual stress of 19 MPa, and the number of times of destruction was evaluated. (5) Slidability According to JIS K7218 A method, S45
Using a C ring, load 5kg (contact pressure 2.5kg / c
m ² ), a sliding test was performed under the conditions of a peripheral speed of 10 cm / sec and a running time of 10 hours, and a specific wear amount was calculated from the wear amount by the following equation. Specific wear (mm ³ / kg · km) = wear (g) / density (g / mm ³ ) / load
(kg) / Running distance (km) (6) Appearance of molded article The appearance of a test piece used for the repeated bending fatigue test was visually observed and evaluated according to the following steps. ：: good Δ: slightly poor ×: poor The results above are summarized in Table 1.

[0024]

[Table 1]

[0025]

Industrial Applicability The polycarbonate resin composition of the present invention is excellent in mechanical strength and heat resistance and has improved slidability, so that it is useful for various sliding uses such as gears. Its industrial utility is great, and it is particularly useful in many fields such as electric and electronic fields and parts for OA equipment.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Naoto Obayashi 5-6-1, Higashi-Hachiman, Hiratsuka-shi, Kanagawa Prefecture Inside the Technology Center of Mitsubishi Engineering-Plastics Corporation (72) Takashi Miyajima 5-chome, Higashi-Yawata, Hiratsuka-shi, Kanagawa No. 6-2 Mitsubishi Engineering Plastics Co., Ltd. Technical Center F term (reference) 4J002 CH01W CH02X CP033 4J029 BB11A BB13A BB13B BB15A BH04 HC03 HC05A HC05B

Claims (4)

[Claims] 1 to 100 parts by weight of a polycarbonate resin (A), 1 to 100 parts by weight of a copolycarbonate resin (B) having a structural unit represented by the following structural formulas (1) and (2), and 25 ° C. Has a viscosity of 10,000 mm ² / s
A polycarbonate resin composition comprising the above silicone oil (C) in an amount of 0.1 to 5 parts by weight, and wherein the total of the polycarbonate resin (A) and the copolycarbonate resin (B) is 100 parts by weight. Structural formula (1) Structural formula (2) (In the structural formula (1), n represents an integer of 1 to 200, R represents an alkylene group having 2 to 6 carbon atoms, and X1, X2, X3
And X4 independently represent a hydrocarbon group having 1 to 20 carbon atoms or a halogenated hydrocarbon group. In the structural formula (2), B represents a linear, branched or cyclic alkylidene group having 1 to 10 carbon atoms, an aryl-substituted alkylene group, an aryl group, or —O.
—, —S—, —CO—, —SO—, or —SO ₂ —, and R1, R2, R3, and R4 independently represent hydrogen, halogen, or an alkyl group having 1 to 4 carbon atoms. ) 2. The polycarbonate resin composition according to claim 1, wherein the viscosity of the silicone oil (C) at 25 ° C. is 100,000 mm ² / s or more. 3. The polycarbonate resin composition according to claim 1, wherein the viscosity of the silicone oil (C) at 25 ° C. is 1,000,000 mm ² / s or more. 4. The copolycarbonate resin (B) according to claim 1, wherein the proportion of the structural unit represented by the structural formula (1) is 0.2 to 50% by weight. A polycarbonate resin composition according to any one of the above.