JPH0791436B2 - Matte resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a matte resin composition having excellent impact resistance and flowability.

<Prior Art> Rubber-modified styrenic resins represented by ABS resins have excellent mechanical properties such as impact resistance and rigidity and workability, as well as excellent appearance of molded products such as gloss, and are used for automobile parts, office equipment parts, It is used for a wide range of purposes such as sundries. However, recently, mainly for automobile interior parts, there is an increasing demand for a matte material having a low gloss, from the viewpoint of safety or in order to obtain a matte, soft texture.

Conventionally, as a delustering method for rubber-modified styrene resin,
It has been proposed to add (i) an inorganic filler such as calcium carbonate, (ii) a rubbery polymer, and (iii) an epoxy group-containing olefin copolymer.

<Problems to be Solved by the Invention> In the above-described matting method, the addition of the (i) inorganic filler has a drawback that the impact resistance, which is a characteristic of the rubber-modified resin, is significantly lowered. Further, (ii) the addition of the rubbery polymer causes defects such as flow marks on the surface of the molded product, and there is a problem that a uniform matte surface cannot be obtained. (Iii) The addition of the epoxy group-containing olefin copolymer is carried out according to the above (i) and (i
Compared with the method i), it has an advantage in that it has an excellent matte effect and that a uniform matte surface without defects can be obtained.
There is a problem that the flowability of the resin decreases as the amount of addition increases.

<Means for Solving Problems> The inventors of the present invention have conducted extensive studies to improve the above-mentioned problems, and as a result, by adding a specific polymer to the rubber-modified styrene-based resin, the flowability was lowered. The inventors have found that a thermoplastic resin composition which gives a surface of a molded article having a small and sufficient matte surface is obtained, and thus the present invention has been accomplished.

That is, the present invention is selected from rubber modified styrene resin (A) 80 to 99.8% by weight, hydroxyethyl acrylate and / or hydroxypropyl acrylate, aromatic vinyl monomer and other copolymerizable monomer. The polymer (B) obtained by polymerizing one or more monomers is 0.2 to 20% by weight, and the content of hydroxyethyl acrylate and / or hydroxypropyl acrylate in the composition is 0.1 to 2.5% by weight. The present invention provides a matte resin composition excellent in impact resistance and flowability, characterized by being mixed in a ratio.

The present invention will be described in detail below.

<Rubber-modified styrene-based resin (A)> The rubber-modified styrene-based resin (A) in the present invention means an aromatic vinyl-based monomer in the presence of rubber and a monomer copolymerizable therewith, if necessary. Or a graft copolymer obtained by polymerizing the same, or an aromatic vinyl-based polymer obtained by polymerizing the graft copolymer with an aromatic vinyl-based monomer and, if necessary, a monomer copolymerizable therewith. It is a mixture with coalescence.

As the rubber, butadiene rubber (i) such as polybutadiene, butadiene-styrene copolymer, butadiene-acrylonitrile copolymer, etc., binary copolymer (EPR) consisting of ethylene and propylene or butene, ethylene, propylene or butene, and Ethylene-α olefin rubber (i.e., terpolymer (EPDM) composed of non-conjugated dienes)
i), in the presence or absence of a cross-linking agent, an alkyl acrylate having an alkyl group having 1 to 16 carbon atoms (methyl acrylate, ethyl acrylate, butyl acrylate,
Alkyl acrylate rubber (iii) obtained by polymerizing or copolymerizing one or two or more of (2-ethylhexyl acrylate, etc.), and optionally one or more of other copolymerizable monomers. Ethylene-vinyl acetate copolymer (iV), chlorinated polyethylene (V), etc. are exemplified, and one kind or two or more kinds can be used.

Aromatic vinyl monomers include styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene,
p-methylstyrene, t-butylstyrene, α-methylvinyltoluene, dimethylstyrene, chlorostyrene,
Dichlorostyrene, bromostyrene, dibromostyrene, vinylnaphthalene, etc. are exemplified, and one or more kinds can be used.

As the monomer copolymerizable with the aromatic vinyl monomer,
Vinyl cyanide monomers such as acrylonitrile, methacrylonitrile, ethacrylonitrile, fumaronitrile,
Unsaturated carboxylic acid alkyl ester monomers such as methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, 2-ethylhexyl methacrylate, maleimide,
N-phenylmaleimide, N-methylmaleimide, N-
Examples include maleimide-based monomers such as cyclohexylmaleimide and unsaturated amide-based monomers such as acrylamide and methacrylamide, and one or more of them can be used.

Preferred examples of the rubber-modified styrene-based resin include butadiene-based rubber-modified acrylonitrile-styrene copolymer (ABS) and butadiene-based rubber-modified styrene polymer (HIP
S), butadiene rubber modified methyl methacrylate-styrene copolymer (MBS), butadiene rubber modified acrylonitrile-methyl methacrylate-styrene copolymer (ABSM), butadiene rubber modified acrylonitrile-α
-Methylstyrene-styrene copolymer, butadiene rubber-modified acrylonitrile-α-methylstyrene-methylmethacrylate-styrene copolymer, butadiene rubber-modified styrene-N-phenylmaleimide copolymer, butadiene rubber-modified acrylonitrile-styrene- Examples thereof include N-phenylmaleimide copolymers and butadiene-based rubber-modified styrene-methylmethacrylate-N-phenylmaleimide copolymers. Further, the butadiene-based rubber (i) in these copolymers is ethylene-α-olefin-based. The rubber (ii), alkyl acrylate rubber (iii), ethylene-vinyl acetate copolymer (iV) or chlorinated polyethylene (V) may also be used as a substitute. These can be used alone or in combination of two or more.

As a method for producing the rubber-modified styrene-based resin, an emulsion polymerization method, a suspension polymerization method, a bulk polymerization method, a solution polymerization method, or a combination thereof is used.

<Polymer (B)> The polymer (B) in the present invention is one selected from hydroxyethyl acrylate and / or hydroxypropyl acrylate, an aromatic vinyl monomer and another copolymerizable monomer. It is a polymer obtained by polymerizing the above monomers.

Examples of the aromatic vinyl-based monomer include the same as those described in the section of the rubber-modified styrene-based resin (A).

Other copolymerizable monomers include vinyl cyanide-based monomers, unsaturated carboxylic acid alkyl ester-based monomers, and maleimide-based monomers described in the section of rubber-modified styrene-based resin (A). And unsaturated amide monomers and butadiene, isoprene, chloroprene and the like.

The polymer (B) of the present invention contains hydroxyethyl acrylate and / or hydroxypropyl acrylate as an essential component, and when hydroxyethyl methacrylate and / or hydroxypropyl methacrylate is used in place of the monomer, a matting effect is obtained. It is not preferable because it is inferior.

The polymer (B) is obtained by copolymerizing hydroxyethyl acrylate and / or hydroxypropyl acrylate with another monomer, and hydroxyethyl acrylate and It may be obtained by graft-copolymerizing hydroxypropyl acrylate.

As the method for producing the polymer (B), an emulsion polymerization method, a suspension polymerization method, a bulk polymerization method, a solution polymerization method or a polymerization method combining these methods is used.

Preferred examples of the polymer (B) include styrene-hydroxyethyl (propyl) acrylate copolymer, acrylonitrile-styrene-hydroxyethyl (propyl).
Acrylate copolymer, methyl methacrylate-styrene-hydroxyethyl (propyl) acrylate copolymer, acrylonitrile-styrene-methyl methacrylate-hydroxyethyl (propyl) acrylate copolymer, butadiene rubber modified acrylonitrile-styrene-hydroxyethyl (propyl) Examples thereof include acrylate copolymers.

The composition of the present invention comprises a rubber-modified styrenic resin (A) 80-
99.8% by weight and 0.2 to 20% by weight of the polymer (B). If the rubber-modified styrene resin (A) is less than 80% by weight, the balance between impact resistance and flowability is poor, and if it exceeds 99.8% by weight, the matting effect is insufficient. Preferably 85-9
It is 9.5% by weight.

The content of hydroxyethyl acrylate and / or hydroxypropyl acrylate shown in the composition is 0.1 to 2.5% by weight. If the content is less than 0.1% by weight, the matting effect is insufficient, and if it exceeds 2.5% by weight, the flowability is poor, which is not preferable. Preferably 0.5 to 2.0% by weight
Is.

The method for mixing the rubber-modified styrenic resin (A) and the polymer (B) is not particularly limited, and they can be mixed in a latex state or in a state of powder, beads, pellets or the like. As a melt-kneading method, a known method such as a Banbury mixer, a roll or an extractor can be adopted.

At the time of mixing, if necessary, an antioxidant, an ultraviolet absorber, an antistatic agent, a lubricant, a dye, a pigment, a plasticizer, a flame retardant,
Additives such as release agents can be added. Further, a thermoplastic resin such as polyacetal, polycarbonate, polybutylene terephthalate, polyphenylene oxide, polymethylmethacrylate, or polyvinyl chloride can be appropriately blended.

Next, the present invention will be specifically described with reference to examples and comparative columns. The numbers of parts and percentages are shown on a weight basis.

Reference Example <Production of Rubber-Modified Styrene Resin (A)> A-1 Nitrogen-replaced reactor had an average particle size of 0.4 μ and a gel content of 8
After charging 100 parts of 0% polybutadiene latex having a solid content of 50%, 0.3 part of potassium persulfate and 100 parts of pure water, the temperature was raised to 65 ° C. with stirring. After that, a mixed monomer solution consisting of 15 parts of acrylonitrile, 35 parts of styrene and 0.2 part of t-dodecyl mercaptan and disproportionated potassium rosinate 2
30 parts of an emulsifier aqueous solution containing 10 parts of each was continuously added over 4 hours, and then the polymerization system was heated to 70 ° C. and aged for 3 hours to complete the polymerization to obtain a graft copolymer latex.

A-2 Graft copolymer consisting of ethylene-propylene-ethylidene norbornene polymer (propylene content 43, iodine value 9, Mooney viscosity 87) 50%, styrene 34% and acrylonitrile 16% based on a known suspension polymerization method. Got

A-3 Based on a known emulsion polymerization method, crosslinked butyl acrylate-
Acrylonitrile rubber (acrylonitrile content 5%)
A graft copolymer (average particle size of rubber, 0.23 μm) consisting of 50%, styrene 35% and acrylonitrile 15% was obtained.

Ai A reactor charged with nitrogen was charged with 0.3 part of potassium persulfate and 120 parts of pure water, and the temperature was raised to 65 ° C with stirring. After that, 30 parts of acrylonitrile, 70 parts of styrene and 0.3 part of t-dodecyl mercaptan and 30 parts of an emulsifier aqueous solution containing 2 parts of disproportionated potassium rosinate were continuously added for 4 hours each, and then the polymerization system was added. 70 ° C
The temperature was raised to 0 ° C. and the polymerization was completed by aging for 3 hours to obtain an acrylonitrile-styrene copolymer latex.

<Production of Polymer (B)> B-1 After 120 parts of pure water and 0.3 part of potassium persulfate were charged in a reactor substituted with nitrogen, the temperature was raised to 65 ° C with stirring. Then 30 parts of acrylonitrile, 65 parts of styrene, 5 parts of hydroxyethyl acrylate and t-dodecyl mercaptan
30 parts of an emulsifier aqueous solution containing 0.3 parts of a mixed monomer solution and 2 parts of sodium dodecylbenzenesulfonate are continuously added for 4 hours, and then the polymerization system is heated to 70 ° C. and aged for 3 hours to carry out polymerization. It's complete.

B-2 Acrylonitrile-styrene-hydroxypropyl acrylate copolymer was produced in the same manner as in B-1, except that 5 parts of hydroxyethyl acrylate was replaced with 10 parts of hydroxypropyl acrylate.

An acrylonitrile-styrene-hydroxymethacrylate copolymer was produced in the same manner as in B-1 except that the hydroxyethyl acrylate was replaced with hydroxyethyl methacrylate.

B-II In the same manner as B-2 except that hydroxypropyl methacrylate was substituted for hydroxypropyl acrylate,
An acrylonitrile-styrene-hydroxypropyl methacrylate copolymer was prepared.

<Production of Epoxy Group-Containing Olefin Copolymer> An ethylene-glycidyl methacrylate-vinyl acetate copolymer (composition ratio 90-
7-3) was produced by the bulk polymerization method.

Examples 1 to 4 and Comparative Examples 1 to 7 Rubber-modified styrenic resin (A) produced in Reference Example, polymer (B), epoxy group-containing olefin copolymer, SB block ("Toughprene A" manufactured by Asahi Kasei Corp.) And talc ("Micron White # 5000" manufactured by Hayashi Kasei Co., Ltd.) were mixed in the composition shown in Table 1 and melt-kneaded using a 40 mm single screw extruder.

The characteristics of the obtained resin composition were measured by the following methods,
The results are shown in Table 1.

Impact resistance (notched Izod): ASTMD-256 Flowability: High-performance flow tester Surface gloss: 3.5 ounces A test plate of 60 mm x 60 mm and 3 mm thickness is molded using an injection molding machine, and the gloss at the center of the test plate is measured. Was measured at an incident angle of 60 ° using a digital variable angle gloss meter UGV-4D manufactured by Suga Test Instruments Co., Ltd.

<Effects of the Invention> As described above, the resin composition of the present invention is superior in impact resistance, flowability and matteness to conventional ones.

Claims (1)

[Claims] 1. Rubber-modified styrenic resin (A) 80 to 99.8% by weight, selected from hydroxyethyl acrylate and / or hydroxypropyl acrylate, aromatic vinyl monomers and other copolymerizable monomers. Polymer (B) formed by polymerizing one or more monomers in an amount of 0.2 to 20% by weight, and the content of hydroxyethyl acrylate and / or hydroxypropyl acrylate in the composition is 0.1 to 2.5% by weight. A matte resin composition characterized by being mixed with.