JP2000198902A - Thermoplastic resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a resin composition which can give a molding having low repulsive force upon high-speed shock and improved in impact resistance, etc., by including an acrylic ester copolymer with a maleimide copolymer and a graft copolymer. SOLUTION: This composition comprises compounding 5-20 pts.wt. copolymer obtained by polymerizing 50-70 wt.% 1-8C alkyl acrylate (a) with 5-35 wt.% (α-methyl)styrene (b) and having a glass transition point (Tg) of -40 to -20 deg.C, a gel content of 10 wt.% or below, and a reduced viscosity of 0.45-0.75 (as measured on methyl ethyl ketone solubles), 25-55 pts.wt. copolymer obtained by polymerizing 15-35 wt.% component (a) with 45-75 wt.% component (b) and 10-25 wt.% N-phenylmaleimide and having a Tg of 140-170 deg.C and a reduced viscosity of 0.45-0.75 (as measured on methyl ethyl ketone solubles), with 30-55 pts.wt. graft copolymer obtained by grafting 10-90 wt.% component (a) and 10-90 wt.% methyl methacrylate and/or component (a) onto 50-80 pts.wt. butadiene rubber polymer (c) having a volume-mean particle diameter of 20-600 nm and having a grafting ratio of 25-55%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic resin composition, and in particular, has a low repulsion when used at a high speed, a good impact resistance at a high speed, and an excellent heat deformation property. The present invention relates to a thermoplastic resin composition capable of obtaining a molded article excellent in moldability and appearance.

[0002]

2. Description of the Related Art At present, styrene resins, especially ABS resins, have excellent rigidity, impact resistance, heat deformation resistance, molding workability, etc., so that various kinds of goods, interior and exterior materials of automobiles, jar rice cookers, It is widely used for housings and parts of home electric appliances such as microwave ovens and vacuum cleaners, and housings and parts of OA equipment such as telephones and facsimile machines.

[0003] In recent years, it has been desired that interior and exterior materials of automobiles and the like, in particular, be improved in performance at the time of actual impact, in addition to characteristics such as dimensional stability at high temperatures and surface appearance. Therefore, as interior and exterior resin materials for automobiles and the like, a molded article obtained by using the resin material has a low repulsion force when used at a high speed, a high impact resistance at a high speed, and a high heat deformation resistance. There is a demand for a resin having excellent appearance (surface properties) and moldability.

[0004] Various studies have been made to satisfy these characteristics, but none of them have yet been obtained having sufficient characteristics.

For example, JP-A-59-20346 discloses a resin obtained by adding a specific plasticizer to a rubber-reinforced styrenic resin. Volatilizes and does not have satisfactory performance. In addition, the use of polypropylene resin having a specific composition is also being studied, but the surface appearance of the molded product is inferior due to the occurrence of sink marks, and the dimensional stability is also unstable due to the occurrence of warpage. Has the drawback of poor adhesion to other materials.

A composition of an ABS resin and an acrylate copolymer is disclosed in JP-A-58-179.
No. 257, a composition comprising a rubber-containing styrenic resin and an acrylic ester copolymer having a high gel content is disclosed in JP-A-63-17954, and a rubber-containing maleimide-styrene copolymer. It is disclosed that a composition comprising an ABS resin and an acrylate copolymer improves chemical resistance. However, when these compositions are used at high speeds, these compositions have high resilience, low impact resistance at high speeds, and poor surface appearance.

Further, the composition comprising a rubber-containing maleimide-styrene-based copolymer and an acrylate-based copolymer described in Japanese Patent Application Laid-Open No. H8-027336 also has a Further, it is impossible to obtain a performance satisfying the impact resistance and the appearance (surface property) at high speed.

[0008] Further, there are many literatures on the phase structure of ABS resin (the matrix is a styrene-acrylonitrile copolymer or a styrene-acrylonitrile-maleimide copolymer) and the dispersion state of rubber, for example, there are many proposals (for example, practical use). Polymer Alloy Design (issued by the Industrial Research Council))
There is no proposal concerning a phase structure or a rubber dispersion state suitable for a resin whose matrix is composed of a styrene-acrylonitrile copolymer or a maleimide-styrene-acrylonitrile copolymer and an acrylate ester copolymer.

[0009]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems, to reduce the repulsive force of a molded article at high speeds, to have high impact resistance at high speeds, An object of the present invention is to provide a thermoplastic resin composition capable of obtaining a molded article having excellent moldability and appearance (surface properties).

[0010]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that a matrix of a composition comprising a rubber-containing maleimide-based copolymer and an acrylate-based copolymer is prepared by combining the maleimide-based copolymer with acrylic acid. High speed by dispersing a graft copolymer (rubber polymer) in a matrix consisting of a maleimide copolymer and an acrylate copolymer, with a polymer alloy structure in which the ester copolymer is microphase-separated from the ester copolymer. The present inventors have found that the repulsion force at the time of low speed can be reduced, and the impact resistance, heat deformation resistance, molding workability and appearance (surface property) at high speed can be improved.

That is, the thermoplastic resin composition of the present invention is composed of a specific composition, has a low glass transition temperature and a low gel content, and has an acrylic ester copolymer (A) and a maleimide copolymer. A composition containing (B) and the graft copolymer (C), which has low repulsion at high speed use, and has high impact resistance, high temperature deformation resistance, molding workability and appearance (surface property) at high speed. ).

The thermoplastic resin composition according to claim 1 is
(1) 50 to 70% by weight of an alkyl ester of acrylic acid having an alkyl group having 1 to 8 carbon atoms, 15 to 25% by weight of acrylonitrile, 5 to 35% by weight of styrene and / or α-methylstyrene, and copolymerizable therewith Monomer 0
5 to 20 parts by weight of an acrylate ester copolymer (A) having a glass transition point (Tg) of -40 to -20 ° C and a gel content of 10% by weight or less;
(2) 15 to 35% by weight of acrylonitrile, 10 to 25% by weight of N-phenylmaleimide, styrene and / or α
A maleimide copolymer (B) 25 obtained by polymerizing 40 to 75% by weight of methylstyrene and 0 to 30% by weight of a monomer copolymerizable therewith and having a glass transition point (Tg) of 140 to 170 ° C. To 55 parts by weight, (3) the volume average particle size is 20
0-600 nm butadiene rubber polymer (a) 50-
80 parts by weight of a mixture comprising 10 to 90% by weight of styrene and / or α-methylstyrene, 10 to 90% by weight of methyl methacrylate and / or acrylonitrile and 0 to 30% by weight of a monomer copolymerizable therewith (b) ) 20-
A graft copolymer (C) having a graft ratio of 25 to 55% by weight obtained by graft polymerization of 50 parts by weight is used.
Containing 55 parts by weight, and having a reduced viscosity of 0.45 to 0.75 of the methyl ethyl ketone-soluble component of the acrylate copolymer (A) and the maleimide copolymer (B).
dl / g, and the diene rubber polymer (a) is contained in an amount of 30 to 40% by weight in the obtained thermoplastic resin composition.

[0013] The thermoplastic resin composition according to claim 2 is the thermoplastic resin composition according to claim 1, wherein the acrylate ester copolymer (A), the maleimide copolymer (B), and the graft copolymer. It is characterized in that each polymer of the coalescence (C) is polymerized by an emulsion polymerization method.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The acrylate copolymer (A) used in the thermoplastic resin composition of the present invention has 1 carbon atom.
50 to 70% by weight of an alkyl ester of acrylic acid having an alkyl group of from 8 to 8, preferably 55 to 70 in terms of resilience and impact resistance when the obtained molded article is used at a high speed.
70% by weight, 15 to 25% by weight of acrylonitrile, preferably 20 to 25% by weight in terms of impact resistance, 5-35% by weight of styrene and / or α-methylstyrene, preferably 5 to 35% in terms of processability. 30% by weight, more preferably 5 to 25% by weight, and a monomer copolymerizable therewith with 0 to 0%
30% by weight, preferably 0 to 20% by weight, more preferably 0 to 10% by weight (total 100% by weight) in view of the repulsion force and impact resistance when the molded article is used at high speed. . Such an acrylic ester-based copolymer (A)
Has an effect of reducing the repulsion force when the obtained molded body is used at a high speed, improving the impact resistance at a high speed, and improving the moldability.

When the content of the alkyl ester of acrylic acid having an alkyl group having 1 to 8 carbon atoms in the acrylate copolymer (A) is less than 50% by weight, the resilience at high speed use is high, and The impact resistance at high speed decreases, and when it exceeds 70% by weight, the thermal deformation resistance decreases. The reason why the number of carbon atoms is 1 to 8 is from the viewpoint of impact resistance at high speed.

When the content of acrylonitrile in the acrylate copolymer (A) is less than 15% by weight or more than 25% by weight, the resilience at the time of use at high speed is high, and the impact resistance at high speed is poor. Lower.

The content of styrene and / or α-methylstyrene is 5% by weight in the acrylate copolymer (A).
If it is less than 35%, the thermal deformation resistance will be low, and if it exceeds 35% by weight, the impact resistance will be low, and the resilience in high-speed use will be high. On the other hand, if the amount of the monomer exceeds 30% by weight in the acrylate-based copolymer (A), the resilience at the time of use at high speed at which copolymerization is possible is high, and the impact resistance at high speed is low, which is not preferable.

The above acrylate copolymer (A)
Tg (glass transition temperature) is -40 to -20C, preferably -3, in consideration of the repulsion force in use at high speed.
5-20 ° C. If the temperature is lower than -40 ° C, the heat deformation resistance is reduced. If the temperature is higher than -20 ° C, the repulsive force in use at high speed is increased.

The gel content of the acrylate copolymer (A) is 10% by weight or less, preferably 5% by weight or less, more preferably 3% by weight from the viewpoint of processability.
It is as follows. If it exceeds 10% by weight, molding processability is undesirably reduced. Here, the gel content means that a 2% solution of methyl ethyl ketone was allowed to stand at 23 ° C. for 24 hours, filtered through a 100-mesh wire gauze, and the filtration residue was dried, and (weight of filtration residue / original weight) × 100. It is a value expressed.

The reduced viscosity of the methyl ethyl ketone-soluble component of the acrylate copolymer (A) is 0.1.
45 to 0.75 dl / g, preferably 0.5 to 0.7 d
1 / g. If it is less than 0.45 dl / g, the impact resistance at high speed becomes low, and if it exceeds 0.75 dl / g, the moldability decreases. Here, the reduced viscosity of the methyl ethyl ketone-soluble component is measured at 30 ° C. in an N, N-dimethylformamide solution.

Examples of the alkyl ester of acrylic acid having an alkyl group having 1 to 8 carbon atoms used in the acrylate copolymer (A) include methyl acrylate and
Ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate and the like can be mentioned, and these can be used alone or in combination of two or more kinds. Particularly, butyl acrylate is preferable from an industrial viewpoint.

Examples of the copolymerizable monomer used in the acrylate copolymer (A) include methacrylonitrile, p-methylstyrene, p-isopropylstyrene, chlorostyrene, bromostyrene, and vinylstyrene. Naphthalene, maleimide, N-methylmaleimide, N-ethylmaleimide, N-propylmaleimide, N-butylmaleimide, N-phenylmaleimide,
N- (p-methylphenyl) maleimide, 2-hydroxylethyl acrylate, (meth) acrylic acid and
Examples include methacrylate monomers such as methyl, ethyl, propyl, butyl, 2-hydroxylethyl, 2-ethylhexyl and glycidyl, and these can be used alone or in combination of two or more.

The maleimide-based copolymer (B) used in the thermoplastic resin composition of the present invention comprises acrylonitrile 15 to 3
5% by weight, preferably 15-30% by weight, N-phenylmaleimide 10-25% by weight, preferably 15-25% by weight, styrene and / or α-methylstyrene 40-7%
5% by weight, preferably 45 to 70% by weight and 0 to 30% by weight of monomers copolymerizable therewith, preferably 0 to 20%
%, More preferably 0 to 10% by weight. Such a maleimide-based copolymer (B) has an effect of increasing heat resistance and deformability.

If the acrylonitrile content in the maleimide-based copolymer (B) is less than 15% by weight, the impact resistance decreases, and if it exceeds 35% by weight, the moldability decreases, and the N-phenylmaleimide content is 10% by weight. %, The thermal deformation resistance decreases, and if it exceeds 25% by weight, the impact resistance decreases,
If the content of styrene and / or α-methylstyrene is less than 40% by weight, the moldability decreases, and if it exceeds 75% by weight, the heat deformation resistance decreases, which is not preferable. Further, when the content of the copolymerizable monomer exceeds 30% by weight, heat deformation resistance and impact resistance decrease, which is not preferable.

Further, from the viewpoints of thermal stability, impact resistance and mold contamination resistance, the above-mentioned mixture of acrylonitrile, N-phenylmaleimide, styrene and / or α-styrene and a monomer copolymerizable therewith. , Styrene and / or α-methylstyrene are preferably at least 49 mol%, more preferably at least 50 mol%.

The Tg of the maleimide-based copolymer (B)
Is 140 to 170 ° C, preferably 150 to 170 ° C, from the viewpoint of heat deformation resistance. If the temperature is lower than 140 ° C., the heat deformation resistance is reduced, and if the temperature exceeds 170 ° C., the moldability is reduced.

The reduced viscosity (30.degree. C., in N, N-dimethylformamide solution) of the methyl ethyl ketone soluble portion of the maleimide copolymer (B) is 0.45 to 0.75 dl /
g, preferably 0.5 to 0.7 dl / g. 0.4
If it is less than 5 dl / g, the impact resistance decreases, and 0.75 dl / g
If it exceeds g, the moldability and the appearance will deteriorate.

Examples of the copolymerizable monomer used in the maleimide-based copolymer include, for example, methacrylonitrile, p-methylstyrene, p-isopropylstyrene, chlorostyrene, bromostyrene, vinylnaphthalene, Maleimide, N-methylmaleimide, N-ethylmaleimide, N-propylmaleimide, N-butylmaleimide, N- (p-methylphenyl) maleimide,
(Meth) acrylic acid and its (meth) acrylate monomers such as methyl, ethyl, propyl, butyl, 2-hydroxylethyl, 2-ethylhexyl, glycidyl and the like, and these may be used alone or in combination of two or more. They can be used in combination.

The maleimide-based copolymer (B) may be a mixture of two or more kinds having different constitutional compositions. For example, a styrene-based copolymer containing no N-phenylmaleimide and a maleimide-based copolymer may be used. It may be a mixture of polymers, as long as the final mixed composition is the above-mentioned composition of the maleimide-based copolymer (B).

The above acrylate copolymer (A)
The maleimide copolymer has a polymer alloy structure in which microphase separation is performed as a matrix in the thermoplastic composition. With such a structure, an effect of reducing the repulsive force at the time of use at high speed and increasing the impact resistance at high speed is exhibited.

The graft copolymer (C) used in the thermoplastic resin composition of the present invention is compatible with the maleimide-based copolymer (B) having the polymer alloy structure and the acrylate-based copolymer (A). It is used to reduce the repulsion of the molded article at high speeds and increase the impact resistance at high speeds.

The rubber polymer used for the graft copolymer (C) is a butadiene rubber polymer (a) having a volume average particle size of 200 to 600 nm, preferably 200 to 500 nm.
It is. If the volume average particle size is less than 200 nm, the impact resistance tends to decrease, and if it exceeds 600 nm, the impact resistance decreases. Such a butadiene rubber polymer (a) may have a different volume average particle size within the above range.
It may be a mixture of more than one species.

The butadiene rubber polymer (a) includes
For example, polybutadiene rubber, styrene-butadiene rubber, acrylonitrile-butadiene rubber, butadiene-
Acrylic ester rubber, hydrogenated styrene-butadiene rubber and the like can be mentioned, and these can be used alone or in combination of two or more.

The method for producing the butadiene rubber polymer (a) is not particularly limited, but the acid group-containing latex (S)
What is manufactured by the enlargement method using is preferable from the point of impact resistance and moldability. Specifically, for example, 5 to 50% by weight of at least one unsaturated acid selected from the group consisting of acrylic acid, methacrylic acid, itaconic acid, and crotonic acid, based on 100 parts by weight (solid content) of rubber latex, An acid group-containing latex prepared by polymerizing 50 to 95% by weight of at least one (meth) alkyl acrylate having 1 to 12 carbon atoms and 0 to 40% by weight of a monomer copolymerizable therewith is used. The rubber polymer produced by the coagulation enlargement method used is preferred.

The butadiene rubber polymer (a) is used in an amount of 50 to 80 parts by weight, preferably 55 to 75 parts by weight, based on the graft copolymer (C). If the butadiene rubber polymer (a) is less than 50 parts by weight, the impact resistance is reduced, and if it is more than 80 parts by weight, the moldability is reduced.

On the other hand, the monomer mixture (b) in the graft copolymer (C) is 10 to 90% by weight, preferably 15 to 85% by weight, more preferably 20 to 90% by weight of styrene and / or α-methylstyrene. 80% by weight, methyl methacrylate and / or acrylonitrile 10 to 90% by weight, preferably 15 to 85% by weight, more preferably 20 to 80% by weight and 0 to 30% by weight of a monomer copolymerizable therewith,
It is preferably composed of 0 to 20% by weight, more preferably 0 to 15% by weight, and 20 to 50% by weight in the graft copolymer (C).
Used in parts by weight. When the amount of the monomer mixture (b) is less than 20 parts by weight or more than 50 parts by weight, impact resistance is reduced.

In the monomer mixture (b), if the content of styrene and / or α-methylstyrene is less than 10% by weight, the moldability is deteriorated, and if it exceeds 90% by weight, the form of breakage upon impact deteriorates. , Impact resistance is reduced. When the content of methyl methacrylate and / or acrylonitrile is less than 10% by weight or more than 90% by weight, the form of fracture at impact deteriorates and the impact resistance decreases. On the other hand, when the content of the copolymerizable monomer exceeds 30% by weight, the form of destruction upon impact deteriorates, and the impact resistance decreases, which is not preferable.

Examples of the copolymerizable monomer in the monomer mixture (b) include methacrylonitrile, p-methylstyrene, p-isopropylstyrene, chlorostyrene, bromostyrene, vinylnaphthalene, maleimide ,
N-methylmaleimide, N-ethylmaleimide, N-propylmaleimide, N-butylmaleimide, N-phenylmaleimide, N- (p-methylphenyl) maleimide, (meth) acrylic acid, and methyl, ethyl, propyl, butyl, Examples include (meth) acrylate monomers such as 2-hydroxylethyl, 2-ethylhexyl and glycidyl, and these can be used alone or in combination of two or more.

The graft copolymer (C) used in the present invention
Is obtained by grafting 50 to 80 parts by weight, preferably 55 to 75 parts by weight of the butadiene rubber polymer (a) and 20 to 50 parts by weight, preferably 25 to 45 parts by weight of the monomer mixture (b). It is prepared by polymerization and has a graft ratio of 25
~ 55% by weight is preferred. If the graft ratio is less than 25%, the form of fracture at impact deteriorates, and the impact resistance decreases. If the graft ratio exceeds 55% by weight, moldability and appearance (surface properties) deteriorate.

Further, the content of the butadiene rubber polymer (a) in the thermoplastic resin composition of the present invention is 30 to 40% by weight, preferably 30 to 35% by weight. When the content of the butadiene-based rubber polymer (a) is less than 30% by weight, the resilience and impact resistance in high-speed use deteriorate, and
If it exceeds 0% by weight, the appearance will be reduced.

The thermoplastic resin composition of the present invention contains 5 to 20 parts by weight, preferably 10 to 20 parts by weight of the acrylate copolymer (A), and 25 to 55 parts of the maleimide copolymer (B). It contains 30 parts by weight, preferably 30 to 55 parts by weight, 30 to 55 parts by weight, preferably 35 to 55 parts by weight of the graft copolymer (C).

When the content of the acrylate copolymer (A) is less than 5 parts by weight, the resilience at the time of use at high speed becomes high, and when it exceeds 20 parts by weight, heat deformation resistance and appearance are reduced. When the content of the maleimide-based copolymer (B) is 55
If the weight part is exceeded, the repulsion force at the time of high-speed use becomes high, and the impact resistance and the formability at the time of high speed decrease,
If the amount is less than 25 parts by weight, the heat deformation resistance is reduced. When the content of the graft copolymer (C) is less than 30 parts by weight, the resilience at the time of use at high speed is increased, and the impact resistance at high speed is reduced. The properties and appearance are undesirably reduced.

Once the composition within the scope of the present invention is obtained, the acrylate copolymer (A), the maleimide copolymer (B) and the graft copolymer (C) are prepared by the polymerization method. Is not particularly limited, any known polymerization method may be used, for example, a known bulk polymerization method, a solution polymerization method,
A suspension polymerization method, an emulsion polymerization method, an emulsion-suspension polymerization method, an emulsion-bulk polymerization method and the like can be used. Preferably, it is preferably prepared using an emulsion polymerization method from the viewpoint of production stability, microphase separation and industrial viewpoint. In particular, the graft copolymer (C) is preferably an emulsion polymerization method because the graft ratio is easily controlled.

In addition, as long as the composition falling within the scope of the present invention is obtained and the desired performance is not impaired, commonly used additives such as initiators, chain transfer agents, surfactants and emulsifiers are usually used. It can be used within the range. Known initiators such as a thermal decomposition initiator such as potassium persulfate and a redox initiator such as Fe-reducing agent-organic peroxide can be used as the initiator. As the chain transfer agent, t-
Dodecyl mercaptan, n-dodecyl mercaptan, α
Known chain transfer agents such as -methylstyrene dimer and terpinolene can be used. Examples of the emulsifier include fatty acid metal salt-based emulsifiers such as sodium oleate, sodium palmitate and sodium rosinate; metal sulfonic acid salts such as sodium dodecylbenzenesulfonate, sodium alkylsulfonate having 12 to 20 carbon atoms and sodium dioctylsulfosuccinate; Known emulsifiers such as a system emulsifier can be used.

Further, the thermoplastic resin composition of the present invention includes:
Normally well-known antioxidants, heat stabilizers, ultraviolet absorbers, pigments, antistatic agents, and lubricants can be appropriately added as needed within the range of ordinary use. In particular, phenolic, sulfur-based, phosphorus-based,
Hindered amine stabilizers, antioxidants, benzophenone-based, benzotriazole-based ultraviolet absorbers and organopolysiloxanes, aliphatic hydrocarbons, esters of higher fatty acids and higher alcohols, amides or bisamides of higher fatty acids and modified products thereof, oligoamides Internal lubricants and external lubricants such as metal salts of higher fatty acids, etc., can be used to make the thermoplastic resin composition of the present invention as a molding resin for higher performance, and these stabilizers are They can be used alone or in combination of two or more.

The thermoplastic resin composition of the present invention may further comprise other styrene resins, for example, acrylonitrile-styrene copolymer, acrylonitrile-styrene-α-methylstyrene copolymer, acrylonitrile-α-methylstyrene copolymer Acrylonitrile-methyl methacrylate-α-methylstyrene copolymer, styrene-maleimide copolymer, styrene-maleic anhydride copolymer, styrene-methyl methacrylate copolymer, methyl methacrylate-butyl acrylate copolymer, methyl methacrylate- 50 butyl acrylate-styrene copolymer
It can be used by mixing at not more than 40% by weight, preferably not more than 40% by weight, in order to further improve the target performance.

Similarly, a polycarbonate resin, a polyvinyl chloride resin, a polyethylene terephthalate resin, a polybutylene terephthalate resin, a polyamide resin and the like can be mixed as long as the performance of the thermoplastic resin composition of the present invention is not impaired. is there.

The thermoplastic resin composition of the present invention containing the acrylate copolymer (A), the maleimide copolymer (B) and the graft copolymer (C) is prepared, for example, by the following method. be able to. As an example, these polymers (A), (B) and (C) are each latex,
Mix in the form of a slurry, a solution, a powder, a pellet, or a combination thereof. When polymer powder is recovered from the latex of the acrylate-based copolymer (A), the latex of the maleimide-based copolymer (B) or the latex of the graft copolymer (C) after polymerization, a usual method, for example, The latex contains an alkaline earth metal salt such as calcium chloride, magnesium chloride or magnesium sulfate, an alkali metal salt such as sodium chloride or sodium sulfate, or an inorganic or organic acid such as hydrochloric acid, sulfuric acid, phosphoric acid or acetic acid. After coagulating la and tex by adding,
Dehydration and drying can be performed. Also, a spray drying method can be used.

At this time, a part of the amount of the stabilizer used may be added in advance in the form of a dispersion to a latex or slurry of these resins.

Further, the thermoplastic resin composition used in the present invention may be an acrylate copolymer (A), a styrene copolymer (B), a graft copolymer (C) alone or a mixture thereof. The above stabilizers and, if necessary, lubricants, pigments, etc. are blended with the powders and pellets composed of a mixture of at least two kinds, and a Banbury mixer, a roll mill, a single-screw extruder,
It can also be prepared by kneading with a known melt kneader such as a shaft extruder.

The thermoplastic resin composition of the present invention thus obtained can be molded by a known molding method such as injection molding, extrusion molding, blow molding, or vacuum molding to produce a molded article. it can.

Examples of the molded body include interior and exterior parts of automobiles, such as front pillars, roof sides, center pillar uppers, center pillar lowers, rear pillars, and the like.
Slide plate, door pocket, door speaker grill, door switch panel, base waist lower, waist garnish, air drafter, rear speaker grill, heurija, rear parcel, coin pocket,
Cluster, side bench, center bench, side differential, front differential, cowl top, glove box,
Column covers, knee vortex, instrument panel, lower driver, lower assist, center panel, meter panel, meter hood, seat back board, seat side, seat back outer, seat back inner, finisher, body console, console box, etc. Parts, bumper, bumper guard, grill guard, radiator grill, spoiler,
There are exterior parts such as door mirrors, and particularly, interior parts such as a front pillar, a center pillar upper, a center pillar lower, and a rear pillar which are required to have impact resistance at high speeds are suitable.

[0053]

The present invention will be described below with reference to the following preparation examples, examples and comparative examples, which do not limit the present invention. Hereinafter, unless otherwise specified, “parts” refers to parts by weight,
“%” Indicates% by weight. However, BA: butyl acrylate, AN: acrylonitrile, St: styrene, tD
M: t-dodecyl mercaptan, CHP: cumene hydroperoxide, PMI: N-phenylmaleimide,
αMSt: α-methylstyrene, BMA: butyl methacrylate, and MAA: methacrylic acid.

(1) Acrylic ester copolymer
Preparation of (A) and maleimide-based copolymer (B) Preparation example A-1) Acrylic ester-based copolymer (A-1)
In a reactor equipped with a stirrer, reflux condenser, nitrogen inlet, monomer inlet and thermometer, 250 parts of pure water, 1.0 part of sodium dioctylsulfosuccinate, 0.5 part of sodium formaldehyde sulfoxylate, EDTA 0 .0
1 part and ferrous sulfate. 0025 parts were introduced.

While stirring this reactor, under a nitrogen stream,
After the temperature was raised to 65 ° C. and reached 65 ° C., the monomer mixture (65 parts of BA, 20 parts of AN, 5 parts of St, 5 parts of tDM0.
35 parts, CHP 0.3 parts) continuously over 10 hours, 1 hour after the start of dropping, 0.5 part of sodium dioctylsulfosuccinate was added, and 5 hours later, sodium dioctylsulfosuccinate was added at 0%. .5 parts were added. After completion of the dropwise addition, stirring was further continued at 65 ° C. for 1 hour to complete the polymerization, thereby producing an acrylate copolymer (A-1).

Preparation Examples A-2 to 4) Acrylate esters
Preparation of copolymer (A-2 to 4) Except for using the monomer mixture and the dropping time shown in Table 1, the acrylate copolymer (A-1) obtained in Preparation Example A-1 Acrylic ester copolymers (A-2 to 4) were produced in the same manner as in the above.

Preparation Examples B-1 to 4) Maleimide-based copolymer
Production of (B-1 to 4) Except for using the monomer mixture and the dropping time shown in Table 2, the same acrylic acid ester-based copolymer (A-1) obtained in Preparation Example A-1 was used. By the method, a maleimide-based copolymer (B-1 to 4) was produced.

The compositions and properties of the polymers obtained in Preparation Examples A-1 to A-4 and B1 to B-4 are shown in Tables 1 and 2, respectively.

[0059]

[Table 1]

[0060]

[Table 2]

(2) Production example of butadiene rubber polymer (a) Preparation example a-1) As the first stage of production of butadiene rubber polymer (a-1), the butadiene rubber polymer (a-1) is enlarged. Required to produce the unexpanded rubber polymer (X). 230 parts of pure water, 0.2 parts of potassium persulfate and 0.2 parts of tDM were introduced into a 100 L polymerization machine.

After the air in the polymerization machine was removed by a vacuum pump, 0.6 part of sodium oleate, 2 parts of sodium rosinate and 100 parts of butadiene were further introduced. The temperature of this system was raised to 60 ° C., and polymerization was carried out for 25 hours.
The polymerization conversion was 96%, and the particle size of the unexpanded rubber polymer (X) was 85 nm.

Next, as a second step, an acid group-containing latex (S) required to enlarge the unexpanded rubber polymer (X) into the butadiene rubber polymer (a) was produced as follows. A reactor equipped with a stirrer, a reflux condenser, a nitrogen inlet, a monomer inlet, and a thermometer, 200 parts of pure water,
0.6 part of sodium dioctyl sulfosuccinate, 0.5 part of sodium formaldehyde sulfoxylate, 0.01 part of sodium ethylenediaminetetraacetate and 0.0025 part of ferrous sulfate were introduced.

While stirring this reactor under a nitrogen stream,
After the temperature was raised to 70 ° C and reached 70 ° C, BMA25
, 5 parts of BA, 0.1 parts of tDM and 0.15 parts of CHP, dropwise over 2 hours, and then BMA
50 parts, 4 parts of BA, 16 parts of MAA, 0.5 part of tDM and 0.15 part of CHP were added dropwise over 4 hours.
Stirring was continued at 70 ° C. for 1 hour to complete the polymerization and obtain an acid group-containing latex (S-1).

Next, as a third step, using the unexpanded rubber polymer (X) and the acid group-containing latex (S-1), a butadiene rubber polymer (a-
1) was manufactured. Acid group-containing latex (S-1) in 100 parts (solid content) of latex of unexpanded rubber polymer (X)
After adding 3.5 parts (solid content) at 60 ° C., stirring was continued for 1 hour to enlarge the product, thereby producing a butadiene rubber polymer (a-1). The particle size of the butadiene rubber polymer (a-1) was 450 nm.

Preparation Example a-2) Butadiene rubber polymer
Preparation Example a--2 except that the monomer mixture shown in Table 3 was used.
An acid group-containing latex (S-2) was produced in the same manner as in the acid group-containing latex (S-1) obtained in 1. The butadiene rubber polymer (a-2) is prepared in the same manner as the butadiene rubber polymer (a-1) except that 2.5 parts (solid content) of the acid group-containing latex (S-2) is used. 2.5 parts (solid content) of the acid group-containing latex (S-2) was added to 100 parts (solid content) of the latex of the unexpanded rubber polymer (X) produced at 60 ° C., and the mixture was stirred for 1 hour. Subsequently, the mixture was enlarged to produce a butadiene rubber polymer (a-2). The particle size of the butadiene rubber polymer (a-2) is 56
It was 0 nm.

Preparation Example a-3) Butadiene rubber polymer (a
In a 100 L polymerization machine, 250 parts of pure water and potassium persulfate were added.
After introducing 2 parts and 0.1 parts of tDM, the air in the polymerization machine was removed by a vacuum pump, and then 0.5 parts of sodium oleate, 2 parts of sodium rosinate and 10 parts of butadiene were added.
0 parts were introduced. The temperature of the system was raised to 50 ° C., and polymerization was carried out for 48 hours. The polymerization conversion was 94%, and the particle size of the butadiene rubber polymer (a-3) was 250 nm.

The composition and properties of the oxygen-containing latex obtained in Preparation Examples a-1 to 3 are shown in Table 3 below.

[0069]

[Table 3]

(3) Production Example of Graft Copolymer (C) Preparation Example C-1) Production of Graft Copolymer (C-1) A stirrer, a reflux condenser, a nitrogen inlet, a monomer inlet, and a thermometer are provided. 280 parts of pure water was added to a reactor prepared in Preparation Example a-1.
65 parts of butadiene rubber polymer (a-1) (solid content), 0.3 part of sodium formaldehyde sulfoxylate, 0.01 part of EDTA and 0.1 part of ferrous sulfate.
0025 parts were introduced.

The reactor was heated to 60 ° C. under a nitrogen stream while stirring, and after reaching 60 ° C.
, 10 parts of St, 15 parts of MMA and 0.2 parts of CHP were added dropwise continuously over 5 hours. After completion of the dropwise addition, stirring was continued at 60 ° C. for 2 hours to complete the polymerization, and a graft polymer (C-1) was obtained.

Preparation Example C-2) Graft Copolymer (C-
Production of 2) A butadiene-based rubber polymer (a-2) was used in place of the butadiene-based rubber polymer (a-1), and polymerization was carried out at the ratio shown in Table 4 to obtain in Preparation Example C-1. In the same manner as the obtained graft copolymer (C-1), the graft copolymer (C
-2).

Preparation Example C-3) Graft copolymer (C-
3) Production was carried out in Preparation Example C-1 except that the unexpanded rubber polymer (X) (particle size: 85 nm) obtained in Preparation Example a-1 was polymerized at the ratio shown in Table 4. Graft copolymer (C-
A graft copolymer (C-3) was produced in the same manner as in 1).

Preparation Example C-4) Graft copolymer (C-
Production of 4) A butadiene rubber polymer (a-3) was used in place of the butadiene rubber polymer (a-1), and polymerization was carried out in the proportions shown in Table 4 to obtain in Preparation Example C-1. In the same manner as the obtained graft copolymer (C-1), the graft copolymer (C
-4).

The compositions and properties of the graft copolymers C-1 to C-4 obtained in Preparation Examples C-1 to C-4 are shown in Table 4 below.

[Table 4]

(4) Production of Thermoplastic Resin Compositions Examples 1 to 11, Comparative Examples 1 to 10 Acrylate copolymer (A) and maleimide copolymer (B) produced in (1) above. And the latex of the graft copolymer (C) produced in (3) were mixed at a predetermined ratio shown in Tables 5 and 6, a phenolic antioxidant was added, and then calcium chloride was added. Coagulated. After heat-treating the obtained coagulated slurry, it is dehydrated and dried to obtain a resin composition powder of a mixture of an acrylate copolymer (A), a maleimide copolymer (B) and a graft copolymer (C). Obtained. Next, 1 part of ethylenebisstearylamide was blended with this powder and uniformly blended with a 20 L blender manufactured by Tabata Co., Ltd.
Using a Tabata single screw extruder with a speed of 40 m / min,
The mixture was melt-kneaded at 0 ° C. to produce pellets of the thermoplastic resin composition (Examples 1 to 11, Comparative Examples 1 to 10).

Test Examples The performances of the thermoplastic resin compositions and molded articles obtained in Examples 1 to 11 and Comparative Examples 1 to 10 were evaluated by the following tests. [Calculation of (Glass transition temperature) Tg] The T of the acrylate copolymer (A) and the maleimide copolymer (B)
g is the Tg of the homopolymer of each component (WILEY INTERSCIEN
CE Publishing, POLYMER HANDBOOKTHIRD EDITION P-VI / 213-229
) Was calculated using the Fox equation.

[Measurement of Gel Content] Calcium chloride was added to the latex of the acrylate copolymer (A) for coagulation, the obtained coagulated slurry was heat-treated, and then the resin powder obtained by dehydration drying was used. The mixture was added to a methyl ethyl ketone solution to give a 2% methyl ethyl ketone solution. The solution was left at 23 ° C. for 24 hours, filtered through a 100-mesh wire net, and dried to measure the residue. The following equation (weight of filtration residue / original weight) × 100 was used for measurement.

[Measurement of Reduced Viscosity] Calcium chloride is added to the latex of the acrylate-based copolymer (A) and the maleimide-based copolymer (B) for coagulation, and the obtained coagulated slurry is heat-treated and then dehydrated. The resin powder obtained by drying is added to a N, N-dimethylformamide solution,
A 0.3 g / dl N, N-dimethylformamide solution was prepared, and the reduced viscosity was measured at 30 ° C. using an Ostwald-type capillary viscometer.

[Graft Ratio of Graft Copolymer] The powder of the graft copolymer (C) was dissolved in methyl ethyl ketone and centrifuged to obtain a methyl ethyl ketone soluble matter and an insoluble matter. The graft ratio was specified from the ratio of the insoluble component to the soluble component.

[Particle size of rubber polymer] The volume average particle size of the butadiene rubber polymer (a) latex was measured using a Nicomp particle size analyzer manufactured by Pacific Science.

[Conversion rate during polymerization] The conversion rate during polymerization was calculated from the solid content concentration (solid content concentration in latex at the end of polymerization). [Characteristics of molded article] The impact resistance of the molded article when used at high speed
Using a Shimadzu Hydro Shot Impact Tester,
It evaluated by the energy at break (unit: J). Energy at break (breaking energy) is 100 × 150 × 2
Using a flat plate having a thickness of 23 mm and a punching speed of 6.7 m /
Measured in seconds. Further, the fracture mode after the test was visually evaluated by ○ (ductile fracture) and × (brittle fracture). The relationship between the energy at break and the content of the diene rubber polymer (a) in the resin is shown in FIG. 3 (prepared from Examples 1, 9, 10, 11 and Comparative Examples 8, 9, 10). From this, the rubber content 2
It can be seen that the energy at break is reduced at 9.3% or less and 45% or more. The repulsive force during use at high speed was evaluated by high-speed tensile strength (unit: kg / cm ² ) and high-speed tensile elongation (unit:%). Measurement was performed at 23 ° C. and a tensile speed of 5 m / sec using a No. 1 dumbbell according to ASTM D638 standard. The lower the tensile strength, the lower the resilience and the better. The heat resistance was evaluated by the amount of dumbbell dripping when a cantilevered dumbbell (one side fixed) was left in an oven at 90 ° C. for 1 hour (unit: mm). The smaller the sag, the better.

As the test piece for the molded article used for the above-mentioned impact strength, tensile strength, tensile elongation, and heat resistance, a FAS100B injection molding machine manufactured by FANUC CORPORATION was used and molded at a cylinder temperature of 250 ° C.

The fluidity (MI) is measured in accordance with JIS K7210.
In case, 220 ℃, 10kg / cm ^TwoEvaluated under the following conditions
(Unit: g / 10 minutes).

The appearance of the molded body is shown in FIGS. 1 and 2 (a vertical rib 2 and a horizontal rib 3 are provided inside a main body 1 having a substantially C-shaped cross section. The unit of the numbers in the figures is mm. )), Color marks and flow marks were visually observed, ○ (good), △ (slightly poor), ×
(Poor) was evaluated. The molded body is Nissei Plastic Industry Co., Ltd.
, 360 TON molding machine, cylinder temperature 250 ° C
What was molded in was used.

The compositions of the thermoplastic resin compositions obtained in Examples 1 to 11 and Comparative Examples 1 to 10 and the performances obtained in the above tests are shown in Tables 5 and 6, respectively.

[0087]

[Table 5]

[0088]

[Table 6]

[0089]

The thermoplastic resin composition of the present invention is
The repulsion at high speed of the molded article obtained by using the thermoplastic resin composition is low, the impact resistance at high speed is high, the heat deformation resistance is high, and the effect of excellent moldability is obtained. Have.

[Brief description of the drawings]

FIG. 1 is a rear view of an example of a molded article using the thermoplastic resin composition of the present invention.

FIG. 2 is a cross-sectional view of an example of a molded article using the thermoplastic resin composition of the present invention.

FIG. 3 is a diagram showing the relationship between the amount of rubber, breaking energy, and breaking mode.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification FI FI Theme Court ゛ (Reference) C08L 33:20 25:02) (C08L 25/02 33:20 35:00) (72) Inventor Satoshi Ichikawa Nissan Motor Co., Ltd. F term (reference) 4J002 BC06X BG04Y BG10X BH01X BN15W GN00 4J011 BB01 BB02 BB09 KA01 KA04 KA05 KA15 KB14 KB19 KB29 NA12 NA25

Claims (2)

[Claims] (1) 50 to 70% by weight of an alkyl ester of acrylic acid having an alkyl group having 1 to 8 carbon atoms, 15 to 25% by weight of acrylonitrile, styrene and / or α
5 to 35% by weight of methylstyrene and 0 to 30% by weight of a monomer copolymerizable therewith, having a glass transition point (Tg) of -40 to -20 ° C and a gel content of 10 % By weight or less of acrylate copolymer (A)
5 to 20 parts by weight, (2) acrylonitrile 15 to 35% by weight, N-phenylmaleimide 10 to 25% by weight, styrene and / or α
A maleimide copolymer (B) 25 having a glass transition point (Tg) of 140 to 170 ° C. obtained by polymerizing 40 to 75% by weight of methylstyrene and 0 to 30% by weight of a monomer copolymerizable therewith; (3) 50-80 parts by weight of a butadiene rubber polymer (a) having a volume average particle diameter of 200-600 nm, 10-90% by weight of styrene and / or α-methylstyrene, methyl methacrylate and / or Alternatively, 20 to 50 parts by weight of a mixture (b) composed of 10 to 90% by weight of acrylonitrile and 0 to 30% by weight of a monomer copolymerizable therewith is graft-polymerized, and the graft ratio is 25 to 55% by weight. 30 to 55 parts by weight of a certain graft copolymer (C), and the methyl acrylate ketone of the acrylate ester copolymer (A) and the maleimide copolymer (B) The reduced viscosity of the solution is 0.45 to 0.75 dl / g
Wherein the diene rubber polymer (a) is contained in an amount of 30 to 40% by weight in the obtained thermoplastic resin composition. 2. An acrylic ester copolymer (A), a maleimide copolymer (B) and a graft copolymer (C)
2. The thermoplastic resin composition according to claim 1, wherein each polymer is polymerized by an emulsion polymerization method.