JP2002241571A - Thermoplastic resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermoplastic resin composition having excellent flowability and molding processability and having excellent clarity when colored, heat resistance, weatherability and impact resistance in the molded product. SOLUTION: This thermoplastic resin composition comprises a maleimide- based copolymer composed of 10-60 wt.% of a maleimide-based monomer unit, 40-90 wt.% of a (meth)acrylic ester monomer unit and 0-50 wt.% of other copolymerizable monomer unit, a thermoplastic resin (a rubber-modified thermoplastic resin or the like) and a thermoplastic elastomer (a hydrogenated diene- based copolymer or the like). The molded product obtained from the composition has >=50% total light transmittance and >=87 deg.C heat distortion temperature.

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 more particularly, to the sharpness of a colored molded article,
The present invention relates to a thermoplastic resin composition having excellent practical impact resistance (hereinafter referred to as “practical impact resistance”) using heat resistance, weather resistance and falling weight impact strength as indices.

[0002]

2. Description of the Related Art In recent years, attempts have been made to use thermoplastic resins as molding materials for unpainted parts for manufacturing exterior parts of vehicles such as automobiles without painting. In conventional molding materials, good appearance, weather resistance and mechanical strength have been obtained by painting, but it is insufficient to provide transparency and heat resistance of colored parts while making use of transparency. Was. For unpainted exterior parts, it is required that all items such as sharpness, heat resistance, weather resistance, and mechanical strength when colored with a coloring agent such as a dye are at a high level. There is a demand for a molding material having both impact properties.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a thermoplastic resin composition which is excellent in sharpness, heat resistance, weather resistance and practical impact resistance of a colored molded article.

[0004]

According to a first aspect of the present invention, there is provided a thermoplastic resin composition comprising a maleimide copolymer, a thermoplastic resin and a thermoplastic elastomer.
The maleimide-based copolymer contains 10 to 60% by weight of a maleimide-based monomer unit (a1), 40 to 90% by weight of a (meth) acrylate monomer unit (a2), and another copolymerizable monomer. Monomer unit (a3) 0 to 50% by weight [however,
The sum of (a1) to (a3) is 100% by weight. ].

The maleimide monomer unit (a1) constituting the maleimide copolymer according to the present invention is not particularly limited. As the monomer constituting the maleimide monomer unit (a1), an N-substituted maleimide monomer is preferable. Examples of the N-substituted maleimide monomer include N-alkylmaleimide having 1 to 4 carbon atoms in the alkyl group, N-phenylmaleimide, N- (p-methylphenyl) maleimide, N-cyclohexylmaleimide and the like. However, N-phenylmaleimide and N-cyclohexylmaleimide are preferred. Further, a monomer obtained by copolymerizing maleic anhydride and imidizing with aniline or the like may be used as the monomer unit (a1). Further, the maleimide-based monomer unit (a1) may be a monomer composed of one of the above-described monomers alone or two or more.

The (meth) acrylate monomer unit (a2) is not particularly limited. Examples of the monomer that constitutes the (meth) acrylate monomer unit (a2) include methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, amyl methacrylate, and methacrylic acid. Methacrylates such as hexyl, octyl methacrylate, 2-ethylhexyl methacrylate, cyclohexyl methacrylate, dodecyl methacrylate, octadecyl methacrylate, phenyl methacrylate, isobornyl methacrylate, benzyl methacrylate, trifluoromethyl methacrylate, and methyl acrylate , Ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate,
And acrylates such as phenyl acrylate and isobornyl acrylate. Of these, methyl methacrylate is preferred. Further, the (meth) acrylic acid ester monomer unit (a2) may be one in which the above exemplified monomers are used alone or in combination of two or more kinds.

The other copolymerizable monomer unit (a3)
Is not particularly limited. Examples of the monomer that constitutes the other copolymerizable monomer unit (a3) include, for example, an aromatic vinyl monomer, a vinyl cyanide monomer, and an unsaturated vinyl monomer. Examples thereof include dicarboxylic anhydrides and vinylcarboxylic acid monomers. Examples of the aromatic vinyl monomer include styrene, α-methylstyrene, α-chlorostyrene, p-methylstyrene and the like.
Styrene and α-methylstyrene are preferred. These can be used alone or in combination of two or more. As the vinyl cyanide monomer,
For example, acrylonitrile, methacrylonitrile and the like can be mentioned, among which acrylonitrile is preferable.
These can be used alone or in combination of two or more.

The unsaturated dicarboxylic acid anhydrides include
For example, maleic anhydride, itaconic anhydride, citraconic anhydride and the like can be mentioned, and among these, maleic anhydride is preferable. Further, these may be constituted by one kind alone or in combination of two or more kinds. Examples of the vinyl carboxylic acid monomer include acrylic acid,
Methacrylic acid and the like can be mentioned, and these can be used alone or in combination of two or more. Among the above monomers, an aromatic vinyl monomer and / or a vinyl cyanide monomer are preferred.

The maleimide-based copolymer includes the maleimide-based monomer unit (a1), the (meth) acrylate monomer unit (a2), and another copolymerizable monomer unit (a3). Is 100% by weight, the maleimide monomer unit (a1) is 10 to 60% by weight (more preferably 10 to 55% by weight, still more preferably 15 to 55% by weight), and (meth) acrylic acid. Ester monomer unit (a2)
From 40 to 90% by weight (more preferably from 45 to 90% by weight, still more preferably from 45 to 84% by weight), and from 0 to 50% by weight (more preferably from other copolymerizable monomer units (a3)). 0 to 45% by weight, more preferably 1 to 40% by weight). If the content of the maleimide-based monomer unit (a1) is too small, or if the content of the (meth) acrylate monomer unit (a2) is too large, the heat resistance of the molded article obtained is inferior. . On the other hand, if the content of the maleimide-based monomer unit (a1) is too large, or if the content of the (meth) acrylate monomer unit (a2) is too small, the molded article obtained has a practical durability. Poor impact and sharpness.

The above-mentioned maleimide-based copolymer is obtained by copolymerizing the above-mentioned monomers, and can be produced by emulsion polymerization, suspension polymerization, bulk polymerization, solution polymerization or the like. The copolymers obtained by the above method may be used alone or in a combination of two or more such that the content of each monomer unit falls within the above range. Also,
The weight average molecular weight of the maleimide-based copolymer is preferably 50,000 or more, more preferably 50,000 to 10
00000, more preferably 80,000 to 400,000
It is. If the weight average molecular weight is too small, the heat resistance and practical impact resistance of the molded article will be poor, while if too large, the moldability will be poor.

The maleimide-based copolymer preferably has a refractive index of 1.47 to 25 ° C. when the D-line is used.
1.60, more preferably 1.48 to 1.59, still more preferably 1.49 to 1.54, particularly preferably 1.49.
To 1.53. When blending the thermoplastic resin and the thermoplastic elastomer and the maleimide-based copolymer, the difference in refractive index between the maleimide-based copolymer and the other components is preferably 0.08 or less, more preferably It is 0.06 or less, more preferably 0.04 or less, and particularly preferably 0.02 or less. The smaller the difference in refractive index, the better the sharpness. Further, the glass transition temperature determined by thermal analysis is preferably 120 ° C. or higher, more preferably 120 to 170 ° C., and further preferably 130 ° C.
To 160 ° C. The higher the glass transition temperature, the better the heat resistance. Further, the maleimide-based copolymer preferably has a content of the maleimide-based monomer remaining in the copolymer of 100 ppm or less, more preferably 80 ppm or less, and still more preferably 60 ppm or less. The smaller the content of the remaining maleimide-based monomer, the better the light resistance of the obtained molded article.

The thermoplastic resin (excluding the maleimide-based copolymer) according to the present invention is not particularly limited, and examples thereof include a (meth) acrylate polymer such as a polycarbonate resin and a PMMA resin, and acrylonitrile. At least two kinds selected from the group consisting of aromatic vinyl monomers such as styrene copolymers, styrene / (meth) acrylate / acrylonitrile copolymers, vinyl cyanide monomers, and (meth) acrylates; A rubber-modified thermoplastic resin obtained by polymerizing a vinyl monomer in the presence of a copolymer obtained by polymerization or a rubbery polymer is exemplified. Of these, a rubber-modified thermoplastic resin is preferably used.

The rubber-modified thermoplastic resin will be described. The rubber-modified thermoplastic resin, in the presence of a rubbery polymer, an aromatic vinyl monomer, a vinyl cyanide monomer,
(Meth) acrylic acid ester, obtained by polymerizing at least one monomer (a), preferably at least two monomers (b) selected from the group of acid anhydride monomers. Polymer (P) or a mixture of this polymer (P) and a (co) polymer of monomer (a), preferably this polymer (P)
And a copolymer of a monomer (b) and a copolymer thereof. In addition, the illustration and preferable monomer of the said monomer are the same as that of the description of the example and preferable monomer described in the description of the said maleimide-type copolymer. The types and amounts of the monomers (a) and (b) polymerized in the presence of the rubbery polymer are as follows:
The resulting rubber-modified thermoplastic resin molded article has a total light transmittance of preferably 50% or more, more preferably 60% or more,
More preferably, it is appropriately selected so as to be 65% or more, particularly preferably 70% or more. The higher the total light transmittance, the better the sharpness. Also, regarding the types and amounts of the monomers (a) and (b) to be added as required, the total light transmittance of the rubber-modified thermoplastic resin obtained after mixing is preferably 50% or more, more preferably 60%. Above, more preferably 65% or more, particularly preferably 70% or more. The difference between the refractive index of the rubbery polymer and the refractive index of the (co) polymer of the monomers (a) and (b) subjected to polymerization in the presence of the rubbery polymer is preferably 0.1. 1 or less, more preferably 0.06 or less, still more preferably 0.1 or less.
04 or less, particularly preferably 0.02 or less. The smaller the refractive index difference, the better the sharpness.

The rubbery polymer used for the rubber-modified thermoplastic resin is not particularly limited, but may be any of a diene rubbery polymer and a non-diene rubbery polymer. Examples of the diene rubbery polymer include natural rubber, polyisoprene, polybutadiene, styrene-butadiene copolymer, butadiene-acrylonitrile copolymer, isobutylene-isoprene copolymer, and aromatic vinyl monomer-conjugated diene block. Copolymers (specific examples: styrene-butadiene block copolymer, styrene-isoprene-styrene block copolymer, styrene-butadiene-styrene block copolymer, etc.) and the like can be mentioned. Examples of the non-diene rubbery polymer include a hydrogenated conjugated diene-based (co) polymer and an ethylene-α-olefin- (non-conjugated diene) copolymer (specific examples: ethylene-propylene- (non-conjugated diene) copolymer). Coalescence, ethylene-butene-1- (non-conjugated diene) copolymer), acrylic rubber, polyurethane rubber, silicone rubber and the like. As the rubbery polymer, a non-diene rubbery polymer is preferably used, and a hydrogenated conjugated diene (co) polymer is more preferably used.

The above-mentioned hydrogenated conjugated diene (co) polymer is preferably a homo-, random, block or the like containing 0 to 60% by weight of an aromatic vinyl monomer unit and 40 to 100% by weight of a conjugated diene monomer unit. (Hydrogen). More preferably, 10 to 60% by weight of an aromatic vinyl monomer unit and 40 to 9 of a conjugated diene monomer unit.
This is a hydrogenated block copolymer of 0% by weight (which may partially contain a random structure). The above hydrogenation is preferably carried out at 7 of the double bond of the conjugated diene moiety.
It is 0% or more, more preferably 90% or more, and still more preferably 95% or more. When the hydrogenation is within the above range, the thermoplastic resin composition of the present invention comprising the rubber-modified thermoplastic resin obtained by using the hydrogenated product is excellent in heat deterioration resistance and weather resistance.

The number average molecular weight of the hydrogenated diene (co) polymer is preferably 5,000 to 1,000,000, more preferably 30,000 to 300,000. The number average molecular weight is determined by gel permeation chromatography using a calibration curve of standard polystyrene. When the number average molecular weight is within the above range, the balance between the molding processability of the thermoplastic resin composition of the present invention comprising the rubber-modified thermoplastic resin obtained by using the hydrogenated product and the physical properties of the impact resistance of the molded product. Will be at a high level. And it is excellent in sharpness. Examples of the aromatic vinyl monomer used for the hydrogenated diene (co) polymer and preferred monomers are the same as those described for the monomer unit (a3). Examples of the conjugated diene monomer include 1,3-butadiene, isoprene, and 1,3-pentadiene.

The rubber-modified thermoplastic resin is preferably obtained by polymerizing a (meth) acrylic ester and another copolymerizable monomer in the presence of a hydrogenated conjugated diene (co) polymer. It is a rubber-modified thermoplastic resin obtained and having a total light transmittance of preferably at least 50%, more preferably at least 60%, further preferably at least 65%, particularly preferably at least 70%. The rubber-modified thermoplastic resin may contain, if necessary, a (co) polymer of the above-mentioned vinyl-based monomer. The higher the total light transmittance, the better the sharpness.

The above-mentioned rubber-modified thermoplastic resin can be produced by subjecting the above-mentioned monomer to emulsion polymerization, suspension polymerization, solution polymerization, bulk polymerization or the like in the presence of the above-mentioned rubbery polymer. Since a rubbery polymer produced by emulsion polymerization is obtained in the form of a latex, production of a rubber-modified thermoplastic resin is usually carried out by an emulsion polymerization method. On the other hand, a rubbery polymer produced by solution polymerization is in a solution state or a solid state. Therefore, the production of a rubber-modified thermoplastic resin is performed by solution polymerization, bulk polymerization, or the like. When polymerizing the rubber-modified thermoplastic resin, a polymerization initiator and a chain transfer agent (molecular weight regulator) are used. In the case of emulsion polymerization, an emulsifier, water and the like are further used. Incidentally, the rubbery polymer and the monomer used for producing the rubber-modified thermoplastic resin, in the presence of the total amount of the rubbery polymer, the monomer may be added at once and polymerized. The polymerization may be carried out by dividing or adding continuously. Moreover, you may superpose | polymerize by the method which combined these. Further, all or a part of the rubbery polymer,
It may be added during the polymerization to carry out the polymerization. When a solid rubbery polymer is used, one of monomers and / or a polymerization solvent may be used.
It can be dissolved in a part or the whole amount and provided for polymerization.

As the polymerization initiator for emulsion polymerization, for example,
Redox system by combining organic hydroperoxides represented by cumene hydroperoxide, diisopropylbenzene hydroperoxide, paramenthane hydroperoxide and reducing agents represented by sugar-containing pyrophosphoric acid formula, sulfoxylate formula, etc. And persulfates such as potassium persulfate. As a polymerization initiator such as suspension polymerization, solution polymerization, bulk polymerization,
For example, peroxides such as benzoyl peroxide (BPO), dicumyl peroxide, lauroyl peroxide, t-butylperoxylaurate, t-butylperoxyisopropyl carbonate, and t-butylperoxymonocarbonate are used. . Further, the polymerization initiator can be added to the polymerization system all at once or continuously. The amount of the polymerization initiator to be used is generally 0.1 to 1.5% by weight, preferably 0.2 to 0.7% by weight, based on the total amount of the monomers.
% By weight. The above polymerization initiators may be used singly or in combination.
More than one species can be used in combination.

Known chain transfer agents can be used.
For example, mercaptans such as octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, n-hexyl mercaptan, n-hexadecyl mercaptan, n-tetradecyl mercaptan, t-tetradecyl mercaptan, dimer of terpinolene and α-methyl styrene And the like. These chain transfer agents may be used alone or in combination of two or more. The amount of the chain transfer agent used is usually 0.1 to the total amount of the monomers.
05 to 2.0% by weight.

As the emulsifier used in the emulsion polymerization, known emulsifiers can be used. For example, higher alcohol sulfates, alkylbenzene sulfonates such as sodium dodecylbenzenesulfonate, and aliphatic sulfonates such as sodium lauryl sulfate. And anionic surfactants such as higher aliphatic carboxylate and phosphoric acid, and nonionic surfactants such as polyethylene glycol alkyl ester type and alkyl ether type. These can be used alone or as a mixture of two or more. The amount of the above-mentioned emulsifier to be used is usually 0.3 to 5.0% by weight based on the total amount of the monomers.

In the case of production by emulsion polymerization, usually, the powder obtained by coagulation with a coagulant is purified by washing with water and drying. As the coagulant, inorganic salts such as calcium chloride, magnesium sulfate, magnesium chloride, and sodium chloride, and acids such as sulfuric acid and hydrochloric acid can be used. When manufacturing by solution polymerization or bulk polymerization,
The residual monomer, the solvent, and the like are removed by a known method, and the rubber-modified thermoplastic resin can be recovered.

The rubber content in the rubber-modified thermoplastic resin is preferably 5 to 70% by weight, more preferably 5 to 6% by weight.
5% by weight. The intrinsic viscosity [η] (30 ° C., methyl ethyl ketone) of the acetone-soluble component of the rubber-modified thermoplastic resin is preferably 0.2 dl / g or more, more preferably 0.25 to 1.5 dl / g. . Further, the graft ratio in the rubber-modified thermoplastic resin is preferably 5%.
As described above, it is more preferably 10 to 150%. If the graft ratio is too small, the molding processability and the impact resistance of the molded product are poor, which is not preferable. The method for measuring the graft ratio is as follows. 1 g of the rubber-modified thermoplastic resin is put into 20 ml of acetone, and the mixture is shaken at room temperature using a shaker.
Shake time, centrifuge (23,000 rpm)
Centrifugation at 60 ° C. for 60 minutes to measure the weight T of the insoluble matter obtained by separating the insoluble matter and the soluble matter.
From the weight S of the rubbery polymer in g, the graft ratio can be determined by the following formula. Graft ratio (%) = 100 × (TS) / S

The thermoplastic elastomer according to the present invention is not particularly limited, and examples thereof include a polyolefin-based thermoplastic elastomer, an aromatic vinyl-based thermoplastic elastomer, a diene-based thermoplastic elastomer, a urethane-based thermoplastic elastomer, and a polyester-based thermoplastic elastomer. And polyamide-based thermoplastic elastomers, PVC-based thermoplastic elastomers, and fluorine-based thermoplastic elastomers.

As the above-mentioned polyolefin-based thermoplastic elastomer (TPO), polyolefins such as polypropylene and polyethylene are used as hard segments, and ethylene-propylene rubber (EPM), ethylene-propylene-diene rubber (EPDM), ethylene-butylene rubber and the like are used as soft segments. And the like. Examples of the aromatic vinyl thermoplastic elastomer include styrene-butadiene block copolymer, styrene-butadiene-styrene block copolymer, styrene- (styrene-butadiene) -styrene block copolymer, and styrene-isoprene-styrene. Copolymer, styrene- (ethylene-butylene) -styrene block copolymer, styrene- (ethylene-propylene) -styrene block copolymer, the above block copolymer in which part or all of styrene is substituted with α-methylene And a hydrogenated conjugated diene-based (co) polymer exemplified above.

Examples of the diene-based thermoplastic elastomer include syndiotactic 1,2-polybutadiene and trans 1,4-polyisoprene. Also,
As the polyester-based thermoplastic elastomer, polybutylene terephthalate as a hard segment,
A multi-block polymer using polytetramethylene ether glycol as a soft segment is exemplified. Further, examples of the polyamide thermoplastic elastomer include block polymers using nylon as a hard segment and polyester or polyol as a soft segment. Of these thermoplastic elastomers, the hydrogenated conjugated diene (co) polymer is preferred. This hydrogenated conjugated diene-based (co) polymer is the same as that described for the rubber-modified thermoplastic resin. When this hydrogenated conjugated diene (co) polymer is used, the effect of improving the practical impact resistance is further improved.

The content ratios of the above maleimide copolymer (A), thermoplastic resin (B) and thermoplastic elastomer (C) are as follows. That is, (A) /
(B) is preferably 5-95 / 5-95, more preferably 10-90 / 10-90, and even more preferably 50-9.
0/10 to 50 (unit;% by weight). The content of (C) is preferably from 0.1 to 100 parts by weight, more preferably from 0.2 to 80 parts by weight, even more preferably from 0.1 to 100 parts by weight, based on 100 parts by weight in total of (A) and (B). It is 2 to 40 parts by weight, particularly preferably 0.2 to 10 parts by weight. (C)
By blending, the falling weight impact strength of the obtained molded article is improved, and a molded article excellent in practical impact resistance can be obtained. If the amount of (C) is too small, the practical impact resistance is poor, while if too large, the heat resistance of the molded product is poor.

The thermoplastic resin composition of the present invention can contain a light stabilizer and an ultraviolet absorber as additives. As the light stabilizer, for example, any of organic nickel-based, hindered amine-based light stabilizers conventionally used in paints, synthetic rubbers, synthetic resins, synthetic fibers, and the like can be used. (2,2 ',
6,6′-tetramethyl-4-piperidyl) sebacate, bis (1,2,2 ′, 6,6′-pentamethyl-4)
-Piperidyl) sebacate, 4-benzoyloxy-
2,2 ′, 6,6′-tetramethylpiperidine, tetraxy (2,2 ′, 6,6′-tetramethyl-4-piperidyl) -1,2,3,4-butanetetracarboxylate, poly {[ 6 (1,1 ', 3,3'-tetramethylbutyl) imino] [1,3,5-triazine-2,4diyl] [4 (2,2', 6,6'-tetramethylpiperidyl) imino ]] Hexamethylene [4 (2, 2 ', 6,
Hindered amine light stabilizers such as 6'-tetramethylpiperidyl) imino]｝. The light stabilizer,
If the content is too large, the molded article may be discolored.

As the above-mentioned ultraviolet absorber, for example, p-
t-butylphenyl salicylate, 2,2′-dihydroxy-4-methoxybenzophenone, 2- (2′-hydroxy-4′-n-octoxyphenyl) benzotriazole, 2- [2-hydroxy-3,5-bis ( α (α-
Dimethylbenzyl) phenyl)]-2H-benzotriazole, 2,2-methylenebis [4- (1,1 ′, 3,
3'-tetramethylbutyl) -6- (2H-benzotriazol-2-yl) phenyl], 2- (2-hydroxy-5-methylphenyl) benzotriazole and the like. The content of the additive comprising the light stabilizer and / or the ultraviolet absorber is preferably 0.01 to 100 parts by weight in total of the maleimide-based copolymer (A) and the thermoplastic resin (B). 10 to 10 parts by weight, more preferably 0.02 to 8.0 parts by weight, still more preferably 0.05 to 10 parts by weight.
It can be 8.0 parts by weight. If the content of the above additive is too small, the desired addition effect cannot be obtained. On the other hand, if it is too large, the weather resistance will be reduced.

The thermoplastic resin composition according to claims 1 and 2 may further contain various known additives such as a lubricant, a flame retardant, a flame retardant auxiliary, a coupling agent, an antibacterial agent, a fungicide, An antioxidant, a plasticizer, a colorant (eg, a pigment or a dye), an antistatic agent, and the like can be blended within a range that does not impair the required performance.

Examples of the above lubricant include paraffin wax, stearic acid, hardened oil, stearamide, methylenebisstearamide, n-butyl stearate, ketone wax, octyl alcohol, lauryl alcohol, hydroxystearic acid triglyceride, silicone oil and the like. Is mentioned.

The thermoplastic resin composition according to claims 1 and 2 is obtained by blending a maleimide-based copolymer, a thermoplastic resin and a thermoplastic elastomer. The total light transmittance can be preferably 50% or more, more preferably 60% or more, still more preferably 65% or more, and particularly preferably 70% or more. Excellent molded products can be obtained. The heat distortion temperature of this molded product is preferably 87 ° C. or higher, more preferably 8 ° C.
The temperature can be 8 ° C. or higher, more preferably 90 ° C. or higher. The refractive index difference between the refractive index of the thermoplastic resin, the refractive index of the maleimide-based copolymer, and the refractive index of the thermoplastic elastomer is preferably 0.08 or less,
More preferably 0.06 or less, still more preferably 0.04
Or less, particularly preferably 0.02 or less. The smaller the difference in refractive index, the better the sharpness.

[0033] The thermoplastic resin composition according to claim 3 is a thermoplastic resin composition containing a maleimide copolymer, a thermoplastic resin and a thermoplastic elastomer, and is a molded article comprising the thermoplastic resin composition. Has a total light transmittance of 50%
And a heat deformation temperature of 87 ° C. or higher.

The maleimide copolymer, the thermoplastic resin and the thermoplastic elastomer according to claim 3 are not particularly limited, but the maleimide copolymer, thermoplastic resin and thermoplastic elastomer exemplified in the description of claim 1 are not particularly limited. A plastic elastomer can be suitably used. The content ratio when the above maleimide-based copolymer is (A), the thermoplastic resin is (B), and the thermoplastic elastomer is (C) is as follows. That is, (A) / (B) is preferably 5 to 95/5 to 95, more preferably 10 to 90/10.
To 90, more preferably 50 to 90/10 to 50 (unit;% by weight). The content ratio of (C) is preferably 0.1 to 100 parts by weight in total of (A) and (B).
To 100 parts by weight, more preferably 0.2 to 80 parts by weight,
More preferably, it is 0.2 to 40 parts by weight, particularly preferably 0.2 to 10 parts by weight. By blending (C),
The falling weight impact strength of the obtained molded article is improved, and a molded article excellent in practical impact resistance can be obtained. If the amount of (C) is too small, the practical impact resistance is poor, while if too large, the heat resistance of the molded product is poor.

The molded article comprising the thermoplastic resin composition according to claim 3 has a total light transmittance of 50% or more, preferably 60% or more, more preferably 65% or more, and particularly preferably 70% or more. . The higher the total light transmittance, the better the sharpness when colored. The heat distortion temperature of the molded article is 87 ° C. or higher, preferably 88 ° C. or higher, more preferably 90 ° C. or higher. The higher the heat distortion temperature, the better the practical heat resistance of the molded product. The difference between the refractive index of the thermoplastic resin, the refractive index of the maleimide-based copolymer, and the refractive index of the thermoplastic elastomer is preferably 0.08 or less, more preferably 0.06 or less.
Hereinafter, it is more preferably 0.04 or less, particularly preferably 0.02 or less. The smaller the difference in refractive index, the better the sharpness.

The thermoplastic resin composition according to the third aspect includes:
Further, various known additives such as light stabilizers, ultraviolet absorbers, lubricants, flame retardants, flame retardant aids, coupling agents, antibacterial agents, antifungal agents, antioxidants, plasticizers, coloring agents (pigments) , Dyes, etc.), antistatic agents and the like can be blended within a range that does not impair the required performance. Examples and preferable addition amounts of the light stabilizer, the ultraviolet absorber and the lubricant are the same as those described above.

The thermoplastic resin composition according to any one of claims 1 to 3 can be mixed with various mixing devices generally used for mixing thermoplastic resins, such as a Banbury mixer, a Brabender, a plast mill, a kneader, and a vented extruder. Although it can be manufactured using these, it is preferable to use an extruder with a vent among these. The form of each component before mixing is not particularly limited, and may be any of pellets, beads, powder, flakes, and the like. Further, the mixing temperature is preferably a temperature equal to or higher than the melting point of the maleimide-based copolymer to be mixed, and therefore, the mixing temperature is preferably 200 ° C. or higher.

[0038]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist thereof.
In Examples and Comparative Examples, parts and percentages are by weight unless otherwise specified. 1. Evaluation method The evaluation method used in this example is as follows. (1) Weight average molecular weight 0.02 g of a maleimide-based copolymer was added to a solvent (THF) 10
After dissolving in water and filtering through a pretreatment disk for liquid chromatography,
The weight average molecular weight was measured by gel permeation chromatography (GPC). The calibration curve was prepared using a polystyrene standard substance. The column was directly connected to two TSK Gel Multipore HXL-M manufactured by Tosoh Corporation, and the eluent was THF, which was detected by an RI detector and measured at a column temperature of 40 ° C.

(2) Glass transition temperature Measured using a differential scanning calorimeter (DSC). (3) Refractive index Measured at 25 ° C. at D line according to JIS K7105.

(4) Graft ratio of rubber-modified thermoplastic resin This is shown in the text.

(5) Melt flow rate (MFR) Measured according to JIS K7210. Measurement temperature is 22
0 ° C., load 98 N, unit is g / 10 g. (6) Izod impact strength Measured according to ASTM D256 (1/4 ", with notch) The unit is J / m. (7) Thermal deformation temperature Measured according to ASTM D648 (1/2", 1
8.6 kg / cm ² ).

(8) Flexural strength Measured according to ASTM D790. The unit is MPa. (9) Flexural modulus Measured according to ASTM D790. The unit is MPa.

(10) Total light transmittance The total light transmittance was measured in accordance with JIS K7105 using a test piece having a length of 80 mm, a width of 55 mm, and a thickness of 2.5 mm. The unit is%.

(11) Weather resistance 0.5 part of carbon black and 0.3 part of calcium stearate were added to 100 parts of the composition, and the mixture was colored and kneaded using an extruder to obtain pellets. The pellets were injection-molded under the molding conditions described below to prepare test pieces having a length of 80 mm, a width of 55 mm, and a thickness of 2.5 mm.
8 minutes / 120 minutes, 10 when the black panel temperature is 63 ° C.
After exposure for 00 hours, the color tone change value ΔE before and after the exposure was calculated. ΔE was calculated by the following equation by measuring the discoloration degree Lab (L: lightness, a: redness, b: yellowness) using a multi-source spectrometer (manufactured by Suga Test Instruments Co., Ltd.). ΔE = √ [(L ₁ −L ₂ ) ² + (a ₁ −a ₂ ) ² + (b ₁ −
b ₂ ) ² ] (where L ₁ , a ₁ and b ₁ are the color tone before exposure, L ₂ , a ₂ ,
b ₂ shows the color tone of the post-exposure. The smaller the value of ΔE, the smaller the change in color and the better the color tone.

(12) Sharpness Using a test piece similar to the test piece in the weather resistance test, the evaluation was visually made. ○ mark: excellent in sharpness. Δ: The sharpness is slightly inferior to ○. X: Poor image clarity. (13) Drop weight impact strength Using a high-speed impact tester Servo Pulser EHF-2H-20L (manufactured by Shimadzu Corporation), length 80 mm, width 55 mm,
The breaking energy of the test piece having a thickness of 2.5 mm was measured.
The measurement conditions were as follows: test specimen holder diameter 43 mmφ, impact rod tip 1
The impact speed is 2.7 mmR and the impact speed is 6.7 m / s. The unit is k
gf · cm.

2. Preparation of maleimide-based copolymer (A) As the maleimide-based copolymer (A), the following (A-1 to (A-1)
3) was used. The weight average molecular weight, glass transition temperature and refractive index are shown in Table 1. (A-1) 25% of N-phenylmaleimide monomer unit,
A maleimide copolymer comprising 70% of methyl methacrylate monomer units and 5% of styrene monomer units. (A-2) N-phenylmaleimide monomer unit 27%,
A maleimide copolymer comprising 50% of methyl methacrylate monomer units and 23% of styrene monomer units. (A-3) N-phenylmaleimide monomer unit 15%,
A maleimide-based copolymer composed of 35% of methyl methacrylate monomer units and 50% of styrene monomer units.

[0047]

[Table 1]

3. Preparation of thermoplastic resin (B) The following rubber-modified thermoplastic resin was used as the thermoplastic resin (B). In the presence of a hydrogenated diene-based (co) polymer (trade name "Dynalon 4600P", manufactured by JSR Corporation)
It is obtained by polymerizing styrene, methyl methacrylate, and acrylonitrile, and has a rubbery polymer content of 28%, a styrene monomer unit of 17%, and a methyl methacrylate monomer unit of 5%.
A rubber-modified thermoplastic resin (B-1) composed of 4.5% and acrylonitrile monomer units of 10.5% and having a graft ratio of 45% was obtained.

4. Thermoplastic Elastomer (C) As the thermoplastic elastomer (C-1), a hydrogenated diene-based copolymer (trade name “Dynalon 8900P”, JS
R) as (C-2), a hydrogenated diene-based copolymer (trade name “Dynalon 8400P”, manufactured by JSR)
Was used. 5. Additive (D) As a light stabilizer (D-1), bis (2,2 ′, 6,6 ′)
-Tetramethyl-4-piperidyl) sebacate as 2- (2-hydroxyl-)
(5-methylphenyl) benzotriazole was used.

6. Examples 1 to 4 and Comparative Examples 1 to 2 According to the formulation shown in Table 2, components (A), (B), (C) and (D) were mixed with a tumbler, and then pelletized using a single screw extruder. Was prepared. The obtained pellets were sufficiently dried and injection-molded at a cylinder temperature of 200 ° C. and a mold temperature of 50 ° C. using an injection molding machine J100E-C5 manufactured by Nippon Steel Works to obtain various evaluation test pieces. . Using this test piece, it was measured by the above-described evaluation method. Table 2 shows the evaluation results.

[0051]

[Table 2]

7. Effects of Example From Table 2, Comparative Example 1 was excellent in fluidity and sharpness of a colored molded product because it did not contain a thermoplastic elastomer, but was inferior in Izod impact strength and falling weight impact strength. In Comparative Example 2, a maleimide-based copolymer having a methyl methacrylate monomer unit less than the range of the present invention was used, and the total light transmittance and the sharpness of the molded product were poor. On the other hand, Examples 1 to 3 were excellent in molding processability, and were excellent in heat resistance, sharpness and practical impact strength of molded products at a high level. Example 4 is good enough to have no practical problem in the sharpness of the molded product, and excellent in practical impact resistance.

[0053]

The thermoplastic resin composition of the present invention is excellent in fluidity and molding processability, and provides sharpness, heat resistance, weather resistance and practical impact resistance of a molded product obtained by coloring the composition. Therefore, it is extremely useful as a molding material for applications requiring strict quality, such as various parts without a coating step.

Continued on the front page (72) Inventor Kazuki Iwai 1-18-1 Kyobashi, Chuo-ku, Tokyo F-term in Techno Polymer Co., Ltd. (reference) 4J002 AC06Y BB05Y BB15Y BC04X BC06X BC07X BG04W BG05W BG06W BG06X BG10X BH02W BL01Y BN14XX BN14XX BP02Y CF10Y CG00X EE036 EJ066 EU076 EU086 EU176 EU186 FD046 FD056 FD170 GN00

Claims (3)

[Claims] 1. A thermoplastic resin composition comprising a maleimide-based copolymer, a thermoplastic resin and a thermoplastic elastomer. The maleimide-based copolymer has a maleimide-based monomer unit (a1) of 10 to 60% by weight and a (meth) acrylate monomer unit (a2) of 40 to 90%.
% By weight, and other copolymerizable monomer units (a3)
50% by weight [however, the total of (a1) to (a3) is 100
% By weight. ]. 2. An additive comprising a light stabilizer and / or an ultraviolet absorber in an amount of 0.001 to 10 parts by weight based on 100 parts by weight of the total of the maleimide-based copolymer, the thermoplastic resin and the thermoplastic elastomer. The thermoplastic resin composition according to claim 1, comprising: 3. A thermoplastic resin composition containing a maleimide-based copolymer, a thermoplastic resin and a thermoplastic elastomer, wherein a molded article comprising the thermoplastic resin composition has a total light transmittance of 50% or more. A thermoplastic resin composition having a heat deformation temperature of 87 ° C. or higher.