JP3335428B2 - Polycarbonate resin composition for molding - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a polycarbonate resin composition for molding. More specifically, dimensional stability,
The present invention relates to a molding polycarbonate resin composition having excellent mechanical strength and good surface appearance.

[0002]

2. Description of the Related Art Conventionally, polycarbonate resins reinforced with fibrous fillers (hereinafter referred to as "polycarbonate resins") have been known.
It is referred to as fiber reinforced polycarbonate resin. ) Is dimensional stability, mechanical strength,
Due to its excellent heat resistance, it is used in a wide range of fields such as cameras, VTRs and facsimile machines. However, such a fiber-reinforced polycarbonate resin has a drawback that its surface appearance is not necessarily beautiful when it is formed into a molded product, and particularly in applications where a good surface appearance is required, such as housings and covers. The range of use was limited.

For the purpose of improving the surface appearance of such a fiber-reinforced polycarbonate resin, it has been proposed to incorporate an aromatic polycarbonate oligomer or polycaprolactone (Japanese Patent Application Laid-Open Nos. 61-241355 and 61-241355).
At present, no satisfactory composition has been obtained yet, and a resin / fat composition having even better performance has been demanded.

The present inventors have conducted intensive studies on the above problems, and as a result, specified a graft polymer obtained by polymerizing an aromatic vinyl compound and a vinyl cyanide compound on polyethylene and / or polypropylene with respect to a polycarbonate resin. It has been found that by blending in an appropriate amount, a fiber-reinforced polycarbonate resin composition having excellent dimensional stability and mechanical strength and good surface appearance can be obtained, and the present invention has been completed.

[0005]

[Means for Solving the Problems] That is, the present invention provides:
50 to 95% by weight of a mixture of 70 to 99% by weight of a polycarbonate resin (A) and 1 to 30% by weight of a graft polymer (B) obtained by polymerizing an aromatic vinyl compound and a vinyl cyanide compound on polyethylene and / or polypropylene. The present invention provides a polycarbonate resin composition for molding which is excellent in dimensional stability and mechanical strength and has good surface appearance, comprising 5 to 50% by weight of a fibrous filler (C).

Hereinafter, the present invention will be described in detail. The polycarbonate resin (A) used in the present invention is a resin obtained by a phosgene method of reacting various dihydroxydiaryl compounds with phosgene, or a transesterification method of reacting a dihydroxydiaryl compound with a carbonate such as diphenyl carbonate. It is coalesced and a typical one is a polycarbonate produced from 2,2-bis (4-hydroxyphenyl) propane (bisphenol A).

As the above dihydroxydiaryl compounds, bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, and 2,2-bis (4-hydroxyphenyl) are used in addition to bisphenol A.
Butane, 2,2-bis (4-hydroxyphenyl) octane, bis (4-hydroxyphenyl) phenylmethane, 2,2-bis (4-hydroxyphenyl-3-methylphenyl) propane, 1,1-bis (4 -Hydroxy-3-tert-butylphenyl) propane, 2,2-bis (4-hydroxy-3-bromophenyl) propane,
2,2-bis (4-hydroxy-3,5-dibromophenyl) propane, 2,2-bis (4-hydroxy-3,
Bis (hydroxyaryl) alkanes such as 5-dichlorophenyl) propane, bis (hydroxyaryl) such as 1,1-bis (4-hydroxyphenyl) cyclopentane and 1,1-bis (4-hydroxyphenyl) cyclohexane Cycloalkanes, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxy-
Dihydroxydiaryl ethers such as 3,3'-dimethyldiphenylether, 4,4'-dihydroxydiphenylsulfide, 4,4'-dihydroxy-3,
Dihydroxydiaryl sulfides such as 3'-dimethyldiphenyl sulfide, 4,4'-dihydroxydiphenyl sulphoxide, 4,4'-dihydroxy-
Dihydroxydiarylsulfoxides such as 3,3'-dimethyldiphenylsulfoxide; dihydroxydiarylsulfones such as 4,4'-dihydroxydiphenylsulfone; and 4,4'-dihydroxy-3,3'-dimethyldiphenylsulfone. Can be

These may be used alone or in admixture of two or more. In addition, piperazine, dipiperidyl hydroquinone, resorcin, 4,4'-dihydroxydiphenyl and the like may be used in combination.

Further, the above-mentioned dihydroxyaryl compound and a phenol compound having three or more valences as shown below may be mixed and used. Phloroglucin, 4,6-dimethyl-2,4,6-tri-
(4-hydroxyphenyl) -heptene-2,4,6-
Dimethyl-2,4,6-tri- (4-hydroxyphenyl) -heptane, 1,3,5-tri- (4-hydroxyphenyl) -benzol, 1,1,1-tri- (4-hydroxyphenyl) -Ethane and 2,2-bis-
[4,4- (4,4′-dihydroxydiphenyl) -cyclohexyl] -propane and the like.

The viscosity-average molecular weight of the polycarbonate resin (A) is not particularly limited, but is usually 10,000 to 100,000, preferably 15,000, in view of moldability and strength.
３５35,000. In producing such a polycarbonate resin, a molecular weight regulator, a catalyst and the like can be used as required.

The graft polymer (B) used in the present invention is a graft polymer obtained by polymerizing polyethylene and / or polypropylene with an aromatic vinyl compound and a vinyl cyanide compound.

The polyethylene constituting the graft polymer (B) means polyethylene generally called low density polyethylene, medium density polyethylene, high density polyethylene, or linear low density polyethylene. In addition, polypropylene is generally isotactic polypropylene, crystalline propylene-ethylene random copolymer, crystalline propylene-ethylene block copolymer, crystalline propylene-
A polypropylene referred to as a butene-1 random copolymer is meant, and atactic polypropylene by-produced during the production of polypropylene does not fall into this category.
Further, ethylene-α-olefin rubber (EPR) and ethylene-α-olefin-conjugated diene rubber (EPDM) which show a rubbery state at ordinary temperature are not included in such a category.

The aromatic vinyl compound constituting the graft polymer (B) includes styrene, α-methylstyrene,
o-methylstyrene, m-methylstyrene, p-methylstyrene, t-butylstyrene, α-methylvinyltoluene, dimethylstyrene, chlorostyrene, dichlorostyrene, bromostyrene, dibromostyrene, vinylnaphthalene, and the like, One type or two or more types can be used. Particularly, styrene is preferred.

Examples of the vinyl cyanide compound constituting the graft polymer (B) include acrylonitrile, methacrylonitrile, fumaronitrile and the like, and one or more kinds thereof can be used. Acrylonitrile is particularly preferred.

[0015] Further, within a range not to impair the object of the present invention,
Part of the aromatic vinyl compound is an unsaturated carboxylic acid alkyl ester such as methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, maleimide, methylmaleimide, and ethylmaleimide. , N-phenylmaleimide, O-chloro-N-phenylmaleimide and the like can be sufficiently substituted.

The ratio between the polyethylene and / or polypropylene constituting the graft polymer (B) and the compound (aromatic vinyl compound and vinyl cyanide compound) is not particularly limited, but polyethylene is preferred in view of the physical properties of the final composition. And / or 100 parts by weight of polypropylene,
The total amount of the aromatic vinyl compound and the vinyl cyanide compound is 20 to 200 parts by weight, preferably 40 to 100 parts by weight.

Further, the weight ratio of the aromatic vinyl compound forming the side chain of the graft polymer (B) to the vinyl cyanide compound is not particularly limited, but may be 80-60 / 20-4.
It is preferably 0 (total weight 100).

The polymerization method for obtaining the graft polymer (B) is also not particularly limited, and may be an emulsion polymerization method, a suspension polymerization method,
Examples include a bulk polymerization method, a solution polymerization method, and a method based on a combination thereof.

The fibrous filler (C) used in the present invention includes, for example, glass fiber, carbon fiber, metal fiber, aromatic polyamide fiber, whisker and the like, and one or more kinds are used. be able to. Further, these fibrous fillers are subjected to a surface treatment such as a silane coupling agent for the purpose of improving the affinity with the resin, and a convergence treatment with an acrylic resin or an epoxy resin for the purpose of further improving the handleability. You may. As these fibrous fillers, short fibrous materials having a fiber diameter of 0.2 to 20 μm and a fiber length of 0.01 to 10 mm can be preferably used.

The composition of the present invention comprises 70 to 99% by weight of the above polycarbonate resin (A) and the graft polymer (B).
It comprises 50 to 95% by weight of a mixture of 1 to 30% by weight and 5 to 50% by weight of a fibrous filler (C). 70% by weight of the polycarbonate resin (A) in the mixture comprising the polycarbonate resin (A) and the graft polymer (B)
If it is less than 100%, the mechanical strength is inferior. If it exceeds 99% by weight, the effect of improving the surface appearance is inferior. Further, if the amount of the mixture in the composition comprising the mixture and the fibrous filler (C) is less than 5% by weight, the mechanical strength and dimensional stability are poor, and if it exceeds 50% by weight, the fluidity is poor, which is not preferable.

The method of mixing the components (A), (B) and (C) and the mixing order are not particularly limited, and they are mixed by a known mixer, for example, a tumbler, ribbon blender, high-speed mixer, etc., and melt-kneaded. You can do it.
It is also possible to simultaneously mix the above three components or mix only specific components, and then add and mix the remaining components.

Further, at the time of mixing, known additives such as an antistatic agent, a release agent, an antioxidant, an ultraviolet absorber, a flame retardant, and a dye / pigment can be added as necessary.

Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited to these Examples.

[Examples] Polycarbonate resin (A),
The graft polymer (B) and the fibrous filler (C) were mixed by a tumbler based on the mixing ratio shown in Table 1, and then melt-kneaded at a cylinder temperature of 280 ° C. using a 40 mmφ vent single screw extruder. To obtain pellets. After drying the pellets at 125 ° C. for 4 hours, the cylinder temperature was set to 300 ° C. and the mold temperature was set to 10 using an injection molding machine of 4 ounces.
An ASTM No. 1 dumbbell for appearance evaluation and an ASTM No. 1 dumbbell for tensile strength test were formed at 0 ° C.

The materials obtained in this example are as follows.

PC: Aromatic polycarbonate resin composed of bisphenol A and phosgene and having a viscosity average molecular weight of 19,000.

B-1: polypropylene (density 0.89 g)
/ Cm ³ , melt flow rate 1.2 g / 10 min) 50
Parts by weight, 15 parts by weight of acrylonitrile and styrene 3
5 parts by weight are subjected to polymerization based on a known suspension polymerization method, followed by dehydration.
After drying, a graft polymer (B-1) was obtained.

C-1: Glass fiber (Asahi Fiberglass Co., Ltd. CS-03MA-409C) C-2: Glass fiber (Nittobo Co., Ltd. PFB-101)

Various test methods are as follows.

Appearance Evaluation The floating (appearance) of the glass on the surface of the test piece and the state of peeling of the surface layer of the gate were visually evaluated according to the following criteria. ：: Less noticeable △: Slightly noticeable ×: Notable

Tensile strength (weld part) According to ASTM D-638.

The test results are shown in Table 1.

[0033]

[Table 1]

[0034]

Industrial Applicability The fiber reinforced polycarbonate resin composition of the present invention is excellent in dimensional stability, mechanical strength and surface appearance, and is particularly required for applications requiring good surface appearance such as housings and covers. Can be suitably used.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Kan Yokoi, 2-10-1, Tsukahara, Takatsuki-shi, Osaka Sumitomo Dow Corporation Takatsuki Laboratory (72) Inventor Yutaka Yoshida 2-1-1, Tsukahara, Takatsuki-shi, Osaka Sumitomo Dow Co., Ltd. Takatsuki Laboratory Examiner Satoshi Morikawa (56) References JP-A-5-78549 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08L 69/00

Claims (1)

(57) [Claims] 1. A polycarbonate resin (A) of 70 to 99.
Wt% of polyethylene and / or polypropylene made by polymerizing an aromatic vinyl compound and vinyl cyanide compound in the graft polymer (B) "However, epoxy group, carboxy
Any functional group of xyl group, hydroxyl group and amino group
No mixture " 1 to 30% by weight of a mixture 50 to 9
A polycarbonate resin composition for molding, comprising 5% by weight and 5 to 50% by weight of a fibrous filler (C).