JPH09157486A - Thermoplastic resin composition - Google Patents

Abstract

(57) [PROBLEMS] To provide a thermoplastic resin excellent in surface appearance of a molded product and material strength. SOLUTION: (A) A rubbery polymer (a) in the presence or absence of (b) an aromatic vinyl compound, or an aromatic vinyl compound and another vinyl monomer copolymerizable with an aromatic vinyl compound. Styrene resin consisting of at least one selected from polymers obtained by polymerizing 20 to 95% by weight (B) wood powder 80 to 5% by weight (C) based on 100 parts by weight of (A) + (B). ) (Meth) acrylic acid ester or (meth) acrylic acid ester-based copolymer obtained by (co) polymerizing a monomer containing (meth) acrylic acid ester as a main component, and having a weight average molecular weight of 50 × 10 ⁴ or more. A thermoplastic resin composition comprising 0.1 to 10 parts by weight of a polymer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic resin excellent in surface appearance and material strength of a molded product.

[0002]

2. Description of the Related Art Wood flour is abundantly supplied as a by-product or waste from a sawmill, a woodworking factory, a pulp manufacturing factory, etc., and is generally cheaper than other resin fillers. By adding wood powder to the thermoplastic resin, the rigidity of the molded product is improved,
Since effects such as a reduction in specific gravity are expected, techniques for blending wood powder with a thermoplastic resin and performing extrusion molding, injection molding, compression molding and the like have been conventionally performed. However, when wood flour and thermoplastic resin are simply mixed, the wood flour does not disperse evenly in the resin, the molded product does not have a smooth surface, problems such as surface gloss and weak material strength There was a problem.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and provides a thermoplastic resin composition which is excellent in surface appearance and material strength of molded articles and can be used in a wide range of applications. The purpose is to do.

[0004]

The present invention has the following constitution in order to solve the above problems. (A) Rubbery polymer (a) Polymerized with or without (b) an aromatic vinyl compound, or an aromatic vinyl compound and another vinyl monomer copolymerizable with the aromatic vinyl compound. 20 to 95% by weight of styrene resin (B) 80 to 5% by weight of wood powder consisting of at least one selected from the polymers obtained by (C) (with respect to 100 parts by weight of the above (A) + (B). (Meth) acrylic acid ester or (meth) acrylic acid ester-based copolymer having a weight-average molecular weight of 50 × 10 ⁴ or more, which is obtained by (co) polymerizing a monomer containing (meth) acrylic acid ester as a main component. The present invention provides a thermoplastic resin composition comprising 0.1 to 10 parts by weight.

BEST MODE FOR CARRYING OUT THE INVENTION

The styrene resin (A) of the present invention comprises an aromatic vinyl compound or an aromatic vinyl compound and another monomer copolymerizable therewith in the presence or absence of a rubbery polymer. Even a (graft) polymer resin (rubber-modified aromatic vinyl resin) obtained by (graft) -polymerizing a monomer component, a thermoplastic resin obtained by polymerizing the above-mentioned monomer component and It may be a blend type graft copolymer resin obtained by blending with a graft polymer resin.

The rubbery polymer used here includes:
For example, polybutadiene, polyisoprene, butyl rubber,
Styrene-butadiene copolymer (styrene content 5-60
% By weight), a styrene-isoprene copolymer,
Acrylonitrile-butadiene copolymer, ethylene-α
-Olefin copolymer, ethylene-α-olefin-
Polyene copolymer, silicone rubber, acrylic rubber, butadiene- (meth) acrylate copolymer, styrene-butadiene block copolymer, styrene-isoprene block copolymer, hydrogenated styrene-butadiene block copolymer, hydrogen Butadiene-based polymer, ethylene-based ionomer and the like. The styrene-butadiene block copolymer and the styrene-isoprene block copolymer include those having an AB type, ABA type, taper type, radial teleblock type structure, and the like. Further, the hydrogenated butadiene-based polymer has, in addition to the hydrogenated product of the block copolymer, a hydrogenated product of a styrene block and a styrene-butadiene random copolymer block, and a 1,2-vinyl bond content in polybutadiene. It includes a hydride of a polymer comprising a block of not more than 20% by weight and a polybutadiene block having a 1,2-vinyl bond content of more than 20% by weight. These rubbery polymers are used alone or in combination of two or more. From the viewpoint of impact resistance, a styrene resin obtained in the presence of a rubbery polymer or a styrene resin obtained in the presence of a rubbery polymer and a styrene resin obtained by polymerization in the absence of a rubbery polymer Preference is given to using mixtures with resins.

As the aromatic vinyl compound, styrene,
t-butylstyrene, α-methylstyrene, p-methylstyrene, divinylbenzene, 1,1-diphenylstyrene, N, N-diethyl-p-aminoethylstyrene,
N, N-diethyl-p-aminomethylstyrene, vinylpyridine, vinylxylene, monochlorostyrene, dichlorostyrene, monobromostyrene, dibromostyrene, fluorostyrene, ethylstyrene, vinylnaphthalene, and the like, particularly styrene, α-methyl Styrene is preferred. These aromatic vinyl compounds are used singly or as a mixture of two or more.

Other monomers include vinyl cyanide compounds such as acrylonitrile and methacrylonitrile; methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amino acrylate, hexyl acrylate, octyl acrylate,
Acrylic esters such as 2-ethylhexyl acrylate, cyclohexyl acrylate, dodecyl acrylate, octadecyl acrylate, phenyl acrylate, benzyl acrylate; methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, amino methacrylate, hexyl methacrylate, octyl methacrylate, 2-ethylhexyl methacrylate. , Cyclohexyl methacrylate,
Methacrylic acid esters such as dodecyl methacrylate, octadecyl methacrylate, phenyl methacrylate and benzyl methacrylate; unsaturated acid anhydrides such as maleic anhydride, itaconic anhydride, citraconic anhydride; unsaturated acids such as acrylic acid and methacrylic acid; maleimide,
N-methylmaleimide, N-butylmaleimide, N-
Α, β- such as (p-methylphenyl) maleimide, N-phenylmaleimide, N-cyclohexylmaleimide
Unsaturated dicarboxylic acid imide compounds; epoxy group-containing unsaturated compounds such as glycidyl methacrylate and allyl glycidyl ether; unsaturated carboxylic acid amides such as acrylamide and methacrylamide; acrylic amine, aminomethyl methacrylate, methacrylic acid amino ether,
Amino group-containing unsaturated compounds such as aminopropyl methacrylate and aminostyrene; 3-hydroxy-1-propene, 4-hydroxy-1-butene, cis-4-hydroxy-2-butene, trans-4-hydroxy-2- Butene, 3-hydroxy-2-methyl-1-propene, 2-
Examples thereof include hydroxyl group-containing unsaturated compounds such as hydroxyethyl acrylate, 2-hydroxyethyl methacrylate and hydroxystyrene; and oxazoline group-containing unsaturated compounds such as vinyl oxazoline.

Among the above-mentioned monomers copolymerizable with the aromatic vinyl compound, particularly preferable are vinyl cyanide compounds, (meth) acrylic acid esters, unsaturated acid anhydrides, unsaturated acids, α, β- Imide compound of unsaturated dicarboxylic acid,
It is one or more monomers selected from epoxy group-containing unsaturated compounds and hydroxyl group-containing unsaturated compounds. Specific examples of other monomers copolymerizable with the preferred aromatic vinyl compound include acrylonitrile, methacrylic acid, methyl methacrylate, maleic anhydride, N-phenylmaleimide, glycidyl methacrylate, and 2-hydroxyethyl methacrylate. is there. Particularly preferred are unsaturated compounds containing a hydroxyl group.

Preferred as the monomer composition of the component (A) are styrene / acrylonitrile copolymers, styrene / methyl methacrylate copolymers, styrene / N-.
Phenylmaleimide copolymer, styrene / N-phenylmaleimide / maleic anhydride copolymer, styrene /
Acrylonitrile / hydroxyl group-containing unsaturated compound copolymer, styrene / acrylonitrile / unsaturated acid copolymer, styrene / acrylonitrile / epoxy group-containing unsaturated compound copolymer, styrene / acrylonitrile / oxyzazoline group-containing unsaturated compound copolymer Is.
The amount of the vinyl monomer copolymerizable with the aromatic vinyl compound is preferably 60% by weight or less, more preferably 50% by weight or less, based on the total amount of the monomers. In the imide compound of the above α, β-unsaturated carboxylic acid, a copolymer of the aromatic vinyl compound and the unsaturated acid anhydride, which is post-imidized (completely or partially), may also be used in the present invention (A). Included in the ingredients.

As the component (A), one of the above-mentioned polymers is used.
These may be used alone or in combination of two or more, and the following are particularly preferable combinations for achieving the object of the present invention. At least 1 selected from styrene, acrylonitrile, and methyl methacrylate in the presence of a rubbery polymer.
Of a grafted product obtained by polymerizing at least one kind selected from an unsaturated compound having at least one kind of functional group selected from a carboxyl group, an acid anhydride group, an epoxy group, a hydroxyl group and an oxazoline group, if necessary. 1 type, or 2 or more types, and at least 1 type selected from styrene, acrylonitrile, and methyl methacrylate, and at least 1 type selected from a carboxyl group, an acid anhydride group, an epoxy group, a hydroxyl group, an oxazoline group, and a maleimide group. At least 1 selected from unsaturated compounds having a functional group of
One or two functional group-modified styrenic resins obtained by polymerizing seeds
One or more and aromatic vinyl compounds and acrylonitrile,
The copolymerization amount of the functional group-containing unsaturated compound of the functional group-modified styrenic resin is 0.5 to 30% by weight, which is composed of a styrenic resin obtained by polymerizing at least one selected from methyl methacrylate and a maleimide compound. It is particularly preferable that the amount of the functional group-containing unsaturated compound in the component A) is 0.001 to 20% by weight.

When the component (A) contains a rubber component, the preferable graft ratio is 10 to 200% by weight. The intrinsic viscosity of the component (A) soluble in methyl ethyl ketone (measured at 30 ° C. with methyl ethyl ketone as a solvent) is preferably 0.2.
~ 0.8 dl / g, more preferably 0.3-0.7 d
1 / g. Further, the weight average molecular weight of the tetrahydrofuran-soluble part of the component (A) is preferably less than 50 × 10 ⁴ in terms of polystyrene. Weight average molecular weight is 50 ×
When it exceeds 10 ⁴ , the fluidity of the obtained composition decreases,
Moldability tends to be difficult, which is not preferable. The component (A) of the present invention can be obtained by known polymerization methods such as emulsion polymerization, suspension polymerization, bulk polymerization and solution polymerization. Particularly preferred are those obtained by emulsion polymerization or solution polymerization. The amount of the component (A) used in the thermoplastic resin composition of the present invention is 20 to 95 with respect to 100 parts by weight of (A) + (B).
%, Preferably 30 to 90% by weight, more preferably 40 to 80% by weight. If the amount used is less than 20% by weight, the surface appearance and material strength of the molded product will be poor, and if the amount used exceeds 95% by weight, the effect obtained by blending wood powder cannot be expected.

The wood powder used in the component (B) of the present invention is not particularly limited to the kind of tree, and pine such as Ezo pine, Todo pine and larch, hemlock, cherry tree,
Examples include cedar, oak, cypress, linden, beech, rawan and firs. These raw woods are cut, and sawdust, sawdust, and wood debris generated during sawing are crushed. Also included are powders such as bamboo grass and powders such as paper, pulp, and chaff. These powders are usually used in the form of powder having a particle size of 50 mesh or more, that is, a particle size of 50 mesh or less, more preferably 70 to 250 mesh. The amount of the component (B) used in the thermoplastic resin composition of the present invention is (A) + (B).
80 to 5% by weight, preferably 70 to 10% by weight, more preferably 60 to 20% by weight, relative to 100 parts by weight of the component
It is. If the amount used is less than 5% by weight, the effect obtained by blending wood powder cannot be expected, and if it exceeds 80% by weight, the surface appearance and material strength of the molded product will be poor.

(Meth) used in the component (C) of the present invention
Acrylic acid esters are, for example, the above-mentioned acrylic acid esters and methacrylic acid esters, and examples of the copolymerizable vinyl monomer used as a copolymerization component as needed include, for example, the above-mentioned vinyl cyanide compounds and aromatic compounds. Examples thereof include vinyl compounds, preferably methyl methacrylate, acrylonitrile, and styrene. The (meth) acrylic acid ester in the monomer component containing the (meth) acrylic acid ester as a main component is preferably 10 to 100% by weight, and more preferably 20 to 1% by weight.
The amount is 00% by weight, more preferably 30 to 99% by weight.
If the content of the (meth) acrylic acid ester is less than 10% by weight, the affinity with wood powder is lowered, and the surface appearance of the molded product is inferior, which is not preferable. The polystyrene-reduced weight average molecular weight of component (C) is 50 × 10 ⁴ or more, preferably 70 × 10 ^{4 to} 800 × 10 ⁴ , and more preferably 10
It is 0 × 10 ⁴ to 600 × 10 ⁴ . If the weight average molecular weight is less than 50 × 10 ⁴ , the surface appearance and material strength of the molded product will be poor, and if it exceeds 800 × 10 ⁴ , the fluidity will decrease. The component (C) of the present invention can be obtained by known polymerization methods such as emulsion polymerization, suspension polymerization, bulk polymerization and solution polymerization. Particularly preferred are those obtained by emulsion polymerization or solution polymerization. The amount of the component (C) used in the present invention is (A) +
(B) 0.1 to 10 parts by weight, preferably 0.5 to 9 parts by weight, and more preferably 1 to 7 parts by weight, relative to 100 parts by weight. If the amount used is outside the range of the present invention, the surface appearance and material strength of the molded product will be poor.

The composition of the present invention is excellent especially in foam molding. The foaming agent and the foaming method used here can be performed by a known method. As the foaming agent, a physical foaming agent or a chemical foaming agent can be used. As the physical foaming agent, inorganic materials such as air, carbon dioxide gas and nitrogen gas, and organic materials such as butane, pentane, hexane and freon can be used. As a chemical foaming agent, sodium bicarbonate +
There are inorganic compounds such as acids, bicarbonates and carbonates, and organic compounds include isocyanate compounds, azo compounds, hydrazine derivatives, semicarbazide compounds, azide compounds, nitroso compounds and triazole compounds.

The composition of the present invention includes glass fiber,
Carbon fiber, metal fiber, glass beads, wollastonite,
Glass milled fiber, rock filler, glass flake, calcium carbonate, talc, mica, kaolin,
Fillers such as barium sulfate, graphite, molybdenum disulfide, magnesium oxide, zinc oxide whiskers, potassium titanate whiskers, glass balloons and ceramic balloons can be used alone or in combination. Among these fillers, the shape of glass fiber and carbon fiber is 6 to
Those having a fiber diameter of 60 μm and a fiber length of 30 μm or more are preferred. These fillers comprise the composition 100 of the present invention.
It is usually used in the range of 1 to 200 parts by weight with respect to parts by weight.

In addition, the composition of the present invention contains known coupling agents, antibacterial agents, antifungal agents, flame retardants, flame retardant aids, antioxidants, weathering (light) agents, plasticizers, silicone oils, Additives such as mineral oil and various other types of confidential oils, colorants (pigments, dyes, etc.), lubricants, metal powders and the like can be added. The thermoplastic resin composition of the present invention can be obtained by kneading each component using various extruders, Banbury mixers, kneaders, rolls and the like. A preferable manufacturing method is a method using an extruder. When kneading the components, the components may be kneaded at once, or may be kneaded by a multi-stage addition method. The thermoplastic resin composition of the present invention thus obtained is molded into various molded articles by injection molding, sheet extrusion, vacuum molding, irregular shape, foam molding, injection press, gas assist molding, press molding, blow molding, etc. can do. Various molded articles obtained by the above-mentioned molding method utilize their excellent properties, such as OA / home appliances field, vehicle / ship field, housing-related fields such as furniture / construction materials, sanitary field, toys / sports field field, and other miscellaneous goods. It can be used in a wide range of fields.

[0018]

EXAMPLES The present invention will be specifically described below with reference to examples. In the examples, parts and% are based on weight unless otherwise specified. The various evaluations in the examples are values measured as follows. Surface appearance of molded product, material strength A flat plate was molded by extrusion molding to obtain a test piece. The surface appearance of the obtained test piece was visually judged. ◯: Smooth surface x: Roughness with a lot of irregularities The material strength is determined by performing a bending test using the obtained test piece.
The bending fracture energy was measured.

Tones of rubbery polymers (a) -1 to (a) -5
As component (a) used in the manufacturing of the present invention (A) a styrene resin, a rubber polymer are shown in Table 1.

[0020]

[Table 1]

Preparation of Styrenic Resins A-1 to A-10 Resins obtained by polymerizing a monomer component in the presence or absence of the rubbery polymers (a) -1 to (a) -5 are obtained. It was
The compositions of these resins are shown in Table 2.

[0022]

[Table 2]

Preparation of Wood Flour (B) Pine / Tsuga = 50/50 A crushed product, which was passed through 100 mesh, was used.

(Meth) acrylic acid ester-based polymer C-
Preparation of 1 to C -4 C-1: Metabrene P531 (weight average molecular weight 450 × 10 ⁴ ) manufactured by Mitsubishi Rayon Co., Ltd. was used. C-2: Mitsubishi Rayon Co., Ltd. METABLEN P530A
(Weight average molecular weight 310 × 10 ⁴ ) was used. C-3: Mitsubishi Rayon Co., Ltd. METABLEN P551A
(Weight average molecular weight 145 × 10 ⁴ ) was used. C-4: Mitsubishi Rayon Co., Ltd. METABLEN P570A
(Weight average molecular weight 25 × 10 ⁴ ) was used.

Other components D-1: Calcium stearate was used as a lubricant. D-2: A wax (Montanic acid ester) manufactured by Hoechst Co. was used as a lubricant. D-3: Azodicarbonamide was used as a foaming agent. D-4: Talc was used.

Examples 1 to 17 and Comparative Examples 1 to 4 Each of the above components was dried to a water content of 0.1% or less,
The ingredients were mixed according to the formulation shown in Table 3, melt-kneaded using a kneader, and then pelletized by an extruder. The obtained pellets were extruded to form a flat plate, which was used as a test piece for surface appearance evaluation and material strength evaluation of a molded product, and evaluated by the evaluation method described above. Table 3 shows the results.

[0027]

[Table 3]

Comparative Example 1 is an example in which the amount of the component (C) used in the present invention was small outside the range of the invention, and the surface appearance and material strength of the molded product were poor. Comparative Example 2 is an example in which the use amount of the component (C) of the present invention is out of the range of the invention, and the surface appearance and material strength of the molded product are poor. Comparative Example 3 is an example in which the component (C) is outside the scope of the invention, and the surface appearance of the molded product and the material strength are poor.
Comparative Example 4 is an example in which the amount of the component (B) used is outside the scope of the invention, and the surface appearance and material strength of the molded product are poor.

[0029]

INDUSTRIAL APPLICABILITY The thermoplastic resin composition of the present invention is excellent in the surface appearance and material strength of molded articles and has a wide range of applications, for example, OA / home appliances field, vehicle / ship field, furniture / building materials and other housing-related fields. It can be used in a wide range of fields, such as the sanitary field, toys and sports field, and other miscellaneous goods.

Continuation of front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display area C08L 33:08)

Claims (1)

[Claims] 1. (A) A rubbery polymer (a) in the presence or absence of (b) an aromatic vinyl compound, or an aromatic vinyl compound and another vinyl copolymerizable with an aromatic vinyl compound. Styrene-based resin consisting of at least one selected from polymers obtained by polymerizing a monomer 20 to 95% by weight (B) Wood flour 80 to 5% by weight With respect to 100 parts by weight of the above (A) + (B) And (C) (meth) acrylic acid ester or (meth) acrylic acid ester as a main component is (co) polymerized, and has a weight average molecular weight of 50 × 10 ⁴ or more (meth) acrylic acid A thermoplastic resin composition comprising 0.1 to 10 parts by weight of an ester copolymer.