JPH11181269A - Resin composition for plating and plated molded product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a molded product for plating comprising PC/ABS-based resin improved in plating properties (adhesive strength, heat cycle and appearance of plated molded product). SOLUTION: This resin composition for plating is obtained by compounding 100 pts.wt. composition comprising (A) 20-90 wt.% polycarbonate resin and (B) 80-100 wt.% rubber-reinforced styrene-based resin with (C) 1-40 pts.wt. graft polymer obtained by polymerizing (c-i) 5-90 wt.% conjugated diene-based rubber with (c-ii) 95-10 pts.wt. mixture comprising 30-95 wt.% 1-3C methacrylic acid alkyl ester and 70-5 wt.% 1-3C acrylic acid alkyl ester. This plated molded article is obtained by plating a molded product obtained by molding the composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plating resin composition obtained by blending a specific graft polymer with a composition comprising a polycarbonate resin and a rubber-reinforced styrenic resin, and molding the resin composition. The present invention relates to a plated molded product obtained by plating a resin molded product.

[0002]

2. Description of the Related Art A composition comprising a polycarbonate resin and an ABS resin (hereinafter, referred to as PC / ABS) is excellent in impact resistance, heat resistance, and workability, and is used for automobile parts, home appliances, office equipment parts. It is used for a variety of applications, including: In particular, there are many cases in which automotive parts are plated and used. The plating method generally includes steps of pretreatment, chemical etching, addition of a catalyst, activation, chemical plating, and electroplating. During this plating process, chemical etching is the most important, and roughening the surface of the molded product forms fine irregularities suitable for the plating base, and adds good adhesion between the resin and the plated metal film I do. As a solvent used for chemical etching, a chromic acid-sulfuric acid oxidizing solution is used. In the case of an ABS resin, sufficient surface roughening is easily performed, but in the case of a polycarbonate resin, sufficient surface roughening is not performed. Preprocessing has been performed. This property cannot be completely compensated by PC / ABS.
For this reason, a method of improving adhesion strength by blending MBS resin (Japanese Patent Publication No. 2-59178) has been proposed, but sufficient plating properties (adhesion strength, heat cycle properties, plating appearance) are still obtained. It is hard to say that it is done.
In addition, PC / ABS has a problem that dispersion tends to be slightly poor under high shear, and a plating film is not fixed in that portion, so that it is not suitable for a large molded product or a molded product having a complicated shape.

[0003]

SUMMARY OF THE INVENTION The present invention relates to a PC / AB
Improvement of plating properties (adhesion strength, heat cycle properties, plating appearance) of S, especially PC / ABS resin composition for plating and plating molding with good plating properties even for large molded products and molded products with complicated shapes The purpose is to provide goods.

[0004]

That is, the present invention relates to 100 parts by weight of a composition comprising 20 to 90% by weight of a polycarbonate resin (A) and 80 to 10% by weight of a rubber-reinforced styrene resin (B). Conjugated diene rubber (c-
i) A mixture of (c-ii) 95 to 5 to 90% by weight of 30 to 95% by weight of alkyl methacrylate having 1 to 3 carbons and 70 to 5% by weight of alkyl acrylate having 1 to 3 carbons. A resin composition for plating comprising 1 to 40 parts by weight of a graft polymer (C) obtained by polymerizing 10% by weight, and a plating molding obtained by plating a resin molded article obtained by molding the resin composition. Goods.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. Polycarbonate resin (A) used in the present invention
Is a polymer obtained by a phosgene method of reacting various dihydroxyl diaryl compounds with phosgene, or a transesterification method of reacting a dihydroxyaryl compound with a carbonate ester such as diphenyl carbonate, and as typical examples, 2,2-bis (4-hydroxyphenyl) propane; polycarbonate resins produced from "bisphenol A".

Examples of the dihydroxydiaryl compounds include bis (4-hydroxydiphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, and 2,2-bis (4-hydroxyphenyl) butane in addition to bisphenol A. , 2,2-bis (4-hydroxyphenyl)
Octane, bisbis (4-hydroxydiphenyl) phenylmethane, 2,2-bis (4-hydroxydiphenyl-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-3,5dibromophenyl) propane, 2,2-bis (4-hydroxy-
Bis (hydroxyaryl) alkanes such as 3,5-dichlorophenyl) propane, 1,1-bis (4-hydroxyphenyl) cyclopentane, 1,1-bis (4
Bis (hydroxyaryl) cycloalkanes such as -hydroxyphenyl) cyclohexane, 4,4'-
Dihydroxy diaryl ethers such as dihydroxy diphenyl ether, 4,4'-dihydroxy-3,3'-dimethyl diphenyl ether, 4,4'-dihydroxy diphenyl sulfide, 4,4'-dihydroxy-3,3'-dimethyl diphenyl sulf Dihydroxydiaryl sulfides such as fido, 4,4′-
Dihydroxydiarylsulfoxides such as dihydroxydiphenylsulfoxide, 4,4′-dihydroxydiphenylsulfone, 4,4′-dihydroxy-3,
And dihydroxydiarylsulfones such as 3′-dimethyldiphenylsulfone.

[0007] These may be used alone or as a mixture of two or more kinds. In addition, piperazine, dipiperidyl hydroquinone, resorcin, 4,4'-dihydroxydiphenyls and the like may be mixed.

Further, the above-mentioned dihydroxydiaryl 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'-hydroxydiphenyl) cyclohexyl) -propane and the like. In producing these polycarbonate resins, a molecular weight modifier, a catalyst and the like can be used as needed.

The rubber-reinforced styrene-based resin (B) used in the present invention is a graft polymer obtained by polymerizing a rubbery polymer with an aromatic vinyl monomer and a vinyl cyanide monomer. b-1) or a mixture comprising a copolymer (b-2) obtained by polymerizing the graft polymer (b-1) with an aromatic vinyl monomer and a vinyl cyanide monomer.

Examples of the rubbery polymer constituting the graft polymer (b-1) include conjugated diene rubbers such as polybutadiene, styrene-butadiene rubber, acrylonitrile-butadiene rubber, ethylene-propylene rubber, and ethylene-propylene rubber.
Examples include ethylene-propylene rubbers such as propylene-nonconjugated diene rubbers, and acrylate rubbers such as polybutyl acrylate. Particularly, a conjugated diene rubber is preferable.

Examples of the aromatic vinyl monomer include styrene, α-methylstyrene, paramethylstyrene, bromostyrene, and the like, and one or more kinds can be used. Particularly, styrene and α-methylstyrene are preferred. Examples of the vinyl cyanide-based monomer include acrylonitrile, methacrylonitrile, and the like, and one or more kinds can be used.

In the present invention, it is possible to substitute a part of the aromatic vinyl monomer constituting the graft polymer (b-1) with another copolymerizable monomer. Such monomers include (meth) acrylate monomers such as methyl methacrylate and methyl acrylate,
Maleimide monomers such as N-phenylmaleimide and N-cyclohexylmaleimide; and unsaturated carboxylic acids such as acrylic acid, methacrylic acid, itaconic acid and fumaric acid, each of which can be used alone or in combination of two or more. .

The above-mentioned aromatic vinyl monomer (i), vinyl cyanide monomer (ii) and other copolymerizable monomers
The composition ratio of (iii) is not particularly limited, but (i) 50 to 50%
95% by weight, (ii) 5 to 50% by weight and (iii) 0 to 4
Preferably it is 5% by weight. The composition ratio of the rubbery polymer and the monomer (total) is not particularly limited, but may be 10 to 80% by weight of the rubbery polymer and 90 to 20% by weight of the monomer (total). preferable.

The weight average particle diameter of the rubbery polymer constituting the graft polymer (b-1) is not particularly limited, but is in the range of 0.1 to 2.0 μm, particularly 0.2 to 1.0 μm. Is preferred. Further, the graft ratio of the graft polymer (b-1) is not particularly limited, but is 10 to 150%, particularly 20 to 10%.
A range of 0% is preferred.

The aromatic vinyl monomer and vinyl cyanide monomer constituting the copolymer (b-2) are the same as those exemplified in the section of the graft polymer (b-1). Monomers can be used, and one or two or more monomers can be used. Further, a part of the aromatic vinyl monomer constituting the copolymer (b-2) can be replaced with another copolymerizable monomer. The same monomers as those exemplified in the section of the graft polymer (b-1) can be used, and one kind or two or more kinds can be used respectively.

The above-mentioned aromatic vinyl monomer (i), vinyl cyanide monomer (ii) and other copolymerizable monomers
The composition ratio of (iii) is not particularly limited, but (i) 50 to 50%
95% by weight, (ii) 5 to 50% by weight and (iii) 0 to 4
Preferably it is 5% by weight.

Further, the composition ratio of the graft polymer (b-1) and the copolymer (b-2) constituting the rubber-reinforced styrene resin (B) is not particularly limited. -1) It is preferably from 10 to 100% by weight and the copolymer (b-2) from 0 to 90% by weight.

The graft polymer (b-1) and the copolymer (b-) constituting the rubber-reinforced styrene resin (B)
The polymerization method 2) is not particularly limited, and can be produced by, for example, an emulsion polymerization method, a suspension polymerization method, a solution polymerization method, a bulk polymerization method, or a combination thereof.

The graft polymer (C) used in the present invention refers to a conjugated diene rubber (ci) in an amount of 5 to 90% by weight and alkyl methacrylate 3 having 1 to 3 carbon atoms.
Mixture (c-ii) 9 comprising 0 to 95% by weight and 70 to 5% by weight of an alkyl acrylate having 1 to 3 carbon atoms
It is a graft polymer obtained by polymerizing 5 to 10% by weight.
If the conjugated diene rubber (ci) is less than 5% by weight, the impact resistance is poor, and if it exceeds 90% by weight, the processability is poor. When the alkyl methacrylate having 1 to 3 carbon atoms in the monomer mixture (c-ii) is less than 30% by weight, the plating property is poor, and when it exceeds 95% by weight, the workability is poor.

Examples of the conjugated diene rubber constituting the graft polymer (C) include polybutadiene, styrene-butadiene rubber, acrylonitrile-butadiene rubber and the like. Examples of the alkyl methacrylate having 1 to 3 carbon atoms include methyl methacrylate, ethyl methacrylate, and propyl methacrylate, with methyl methacrylate being particularly preferred. Examples of the alkyl acrylate having 1 to 3 carbon atoms include methyl acrylate, ethyl acrylate, and propyl acrylate, and ethyl acrylate is particularly preferable. The polymerization method of the graft polymer (C) is not particularly limited, and can be produced by, for example, an emulsion polymerization method, a suspension polymerization method, a solution polymerization method, a bulk polymerization method, or a method combining these.

The resin composition of the present invention is a composition 100 comprising the polycarbonate resin (A) in an amount of 20 to 90% by weight and the rubber-reinforced styrene resin (B) in an amount of 80 to 10% by weight.
It is obtained by blending 1 to 40 parts by weight of the graft polymer (C) with respect to parts by weight. If the content of the polycarbonate resin (A) is less than 20% by weight, the impact resistance is poor. If the amount of the graft polymer (C) is less than 1 part by weight per 100 parts by weight of the composition, the plating property is poor, and if it exceeds 40 parts by weight, the plating property is inferior.

The resin composition of the present invention may contain, if necessary,
Other resins such as polycarbonate, polyester, polyphenylene ether and polyamide, various additives such as colorants, dispersants, antioxidants, ultraviolet absorbers, flame retardants, etc., or various reinforcing materials such as glass fiber, carbon fiber and calcium carbonate Etc. can be added. The mixing of the resin composition of the present invention can be carried out by a commonly used method such as a roll, a Banbury mixer, an extruder, or a kneader.

The resin composition thus obtained is molded by injection molding, extrusion molding, compression molding, injection compression molding, blow molding, or the like. Can be plated under the same conditions as the plating conditions of the ABS resin.

[Examples] The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. In the examples, parts and percentages are based on weight.

-Polycarbonate resin (A)-A-1: A polycarbonate resin comprising phosgene and bisphenol A and having a viscosity average molecular weight of 22,100. -Rubber-reinforced styrene-based resin (B)-Graft polymer b-1: a graft polymer comprising 50 parts of polybutadiene (weight average particle diameter 0.30 µ), 35 parts of styrene and 15 parts of acrylonitrile by a known emulsion polymerization method. (Graft ratio: 50%).

Copolymer b-2: A copolymer comprising 70 parts of styrene and 30 parts of acrylonitrile was produced by a known bulk polymerization method. -Graft polymer (C)-C-1: Polybutadiene 30 based on a known emulsion polymerization method
%, Methyl methacrylate 50%, and ethyl acrylate 20% to obtain a graft copolymer latex.
The obtained graft copolymer latex was salted out, dehydrated, and dried to obtain a graft copolymer C-1. C-2: polybutadiene 80 based on a known emulsion polymerization method
%, Methyl methacrylate 16%, and ethyl acrylate 4% were obtained. Salting out, dehydration, of the obtained graft copolymer latex,
It dried and obtained the Graft copolymer C-2. Ci: polybutadiene 60 based on a known emulsion polymerization method
%, Methyl methacrylate 28%, and styrene 12% to obtain a graft copolymer latex. Salting out, dehydration, and drying of the obtained graft copolymer latex,
A Graft copolymer Ci was obtained.

Examples 1-4 and Comparative Examples 1-5 The above polycarbonate resin (A), rubber-reinforced styrene resin (B) (graft polymer b-1, copolymer b-2),
The graft copolymer (C) and the graft copolymer (C) were mixed at the compounding ratio shown in Table 1, and were melt-mixed at a cylinder temperature of 250 ° C. using a 50 mm extruder (manufactured by Tanabe Seiki) to pelletize. Various test pieces were prepared from the obtained pellets using an injection molding machine, and the impact resistance, heat resistance, and moldability were measured.

Impact resistance: A notched Izod impact test was measured according to ASTM D-256. 1/4 inch, 23 ° C (unit: kg / cm / cm) Heat resistance: Complies with ASTM D-648. 1/4 inch,
Without annealing, 18.56 kg / cm ² load (unit:
° C) Formability: Melt flow rate was measured according to ASTM D-1238. Measurement conditions 250 ° C, 5kg (unit: g / 10min)

Further, a molded product for plating (100 × 50 × 3 mm) is formed by using an injection molding machine using a pin gate mold, and plated by the following method, followed by adhesion strength, plating appearance and heat cycle. The properties were measured.

Plating process: degreasing (surfactant aqueous solution, 55 ° C. × 3 minutes), etching (sulfuric acid-chromic anhydride mixed solution, 65-70 ° C. × 15 minutes), neutralization (hydrochloric acid aqueous solution, room temperature × 3 minutes) , Catalyst (palladium chloride-stannous chloride-hydrochloric acid aqueous solution, room temperature x 2 minutes),
Accelerator (sulfuric acid aqueous solution, 45 ° C x 3 minutes),
Electroless plating (nickel plating solution mainly composed of nickel sulfate-sodium hypophosphite-sodium citrate), electroplating (copper sulfate bath → nickel sulfate bath → chromic anhydride bath)

Adhesion strength: According to JIS H-8630, the adhesion strength of the plating film (the stress at the time of making a cut at 1 cm intervals reaching the base material on the metal film of the plated product and peeling the metal film in the vertical direction) (Shown) (kg / c
m ² ).

Plating appearance: The appearance after plating (without plating) was visually determined, and determined according to the following criteria. ；: Good plating with plating on the whole. Δ: Slightly inferior in a part without plating. ×: defective in a state where plating was not applied.

Heat cycle property: -40 ° C (1 hr) →
23 ℃ (0.5hr) → 80 ℃ (1hr) → 23 ℃
(0.5 hr) for 10 cycles, and visually inspected for blisters in the plated molded product.

Table 1 shows the results of these measurements.

[0035]

[Table 1]

[0036]

According to the present invention, the resin composition is PC / A
Improvement of plating property (adhesion strength, heat cycle property, plating appearance) of BS, especially PC / ABS resin composition for plating and plating molding with good plating properties even for large molded products and molded products with complicated shapes A product is obtained.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C25D 5/56 C25D 5/56 B

Claims (3)

[Claims] 1. Polycarbonate resin (A) 20 to 90
% By weight and rubber-reinforced styrenic resin (B) 80 to 10
5 to 90% by weight of the conjugated diene rubber (ci) and 30 to 95% by weight of an alkyl methacrylate having 1 to 3 carbon atoms and 1 to 3% by weight, based on 100% by weight of a composition of 100% by weight. A resin composition for plating comprising 1 to 40 parts by weight of a graft polymer (C) obtained by polymerizing 95 to 10% by weight of a mixture (c-ii) of 70 to 5% by weight of an alkyl acrylate. 2. A graft polymer (b-1) comprising a rubber-reinforced styrene resin (B) obtained by polymerizing an aromatic vinyl monomer and a vinyl cyanide monomer on a rubber polymer, or the graft polymer. The resin composition for plating according to claim 1, wherein the resin composition is a mixture comprising a polymer (b-2) obtained by polymerizing the polymer (b-1), an aromatic vinyl monomer and a vinyl cyanide monomer. Stuff. 3. A plated molded product obtained by plating a resin molded product obtained by molding the resin composition according to claim 1.