JP2013104042A - Transparent rubber-modified styrenic resin composition and molding of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transparent rubber-modified styrenic resin composition and a molding of the same.SOLUTION: The rubber-modified styrenic resin composition includes: 10-90 pts.mass of an acid anhydride group containing copolymer (A) (however, 90 pts.mass is excluded); 0-80 pts.mass of a (meth)acrylic acid ester based copolymer (B) (excluding 0 pt.mass); and 10-35 pts.mass of a graft copolymer (C). The acid anhydride group containing copolymer (A): a copolymer that includes: 15-80 mass% of an aromatic vinyl monomer unit; 15-80 mass% of a (meth)acrylic acid ester based monomer unit; and 5-30 mass% of an unsaturated dicarboxylic anhydride based monomer unit. The (meth)acrylic acid ester based copolymer (B): a copolymer that is chosen from the group consisting of a (meth)acrylic acid ester based monomer, an aromatic vinyl monomer unit, and an acrylate monomer unit. The Graft copolymer (C): a graft copolymer that includes a diene rubber polymer and a styrene-methacrylic acid ester copolymer.

Description

The present invention relates to a transparent rubber-modified styrenic resin composition and a molded product thereof.

The transparent rubber-reinforced styrene-based resin has excellent design properties, mechanical properties, molding processability, electrical insulation, and the like, and is therefore used in general miscellaneous goods, housings and parts of electrical equipment, OA equipment, and the like. As transparent rubber reinforced styrene resin, transparent high impact polystyrene (transparent HIPS resin), transparent methyl methacrylate-butadiene-styrene resin (transparent MBS resin), transparent acrylonitrile-butadiene-styrene resin (transparent ABS resin), etc. are known. ing.

However, in general, the transparent rubber-reinforced styrene-based resin has good impact resistance and light transmittance, but has a problem that heat resistance is not sufficient. There are the following techniques for imparting heat resistance to a transparent rubber-reinforced styrene resin.

JP 2006-70133 A Japanese Patent No. 3168466 Japanese Patent No. 3214003 Japanese Patent No. 3414083 Japanese Patent Laid-Open No. 2002-3528

An object of the present invention is to provide a transparent rubber-modified styrene resin composition and a molded product thereof.

The gist of the present invention is as follows.
(1) Acid anhydride group-containing copolymer (A) 10 to 90 parts by mass (excluding 90 parts by mass), (meth) acrylic acid ester copolymer (B) 0 to 80 parts by mass (provided that 0 The rubber-modified styrenic resin composition comprising 10 to 35 parts by mass of the graft copolymer (C) (excluding parts by mass) [However, the total of (A), (B) and (C) is 100 parts by mass].
Acid anhydride group-containing copolymer (A):
Copolymers comprising 15 to 80% by mass of aromatic vinyl monomer units, 15 to 80% by mass of (meth) acrylic acid ester monomer units, and 5 to 30% by mass of unsaturated dicarboxylic acid anhydride monomer units. Polymer resin composition.
(Meth) acrylic ester copolymer (B):
1 selected from the group consisting of 70 to 99% by mass of (meth) acrylic acid ester monomer units, aromatic vinyl monomer units, and alkyl ester monomer units having 1 to 8 carbon atoms in the alkyl group. A copolymer resin composition comprising 30 to 1% by mass of at least one monomer unit.
Graft copolymer (C):
From 30 to 70% by mass of the diene rubbery polymer (a), from 30 to 70% by mass of the styrene-methacrylic acid ester copolymer (b) composed of a styrene monomer unit and a methacrylic ester monomer unit. A graft copolymer.
(2) Refractive index for d-line at 23 ° C. of acid anhydride group-containing copolymer (A), (meth) acrylic acid ester copolymer (B), and graft copolymer (C), respectively, , Na, nb, nc,
The respective mass ratios of the acid anhydride group-containing copolymer (A), the (meth) acrylic ester copolymer (B), and the graft copolymer (C) in the rubber-modified styrene resin composition, respectively. , Wa, wb, wc (where wa + wb + wc = 1), the rubber-modified styrenic resin composition according to claim 1, wherein the following formulas 1 and 2 are satisfied.
Δn = | na × wa / (wa + wb) + nb × wb / (wa + wb) −nc | (Formula 1)
Δn ≦ 0.005 (Formula 2)
(3) The rubber-modified styrene resin composition according to any one of (1) to (2), wherein the acid anhydride group-containing copolymer (A) has a weight average molecular weight (Mw) of 50,000 to 200,000.
(4) The rubber-modified styrenic resin composition according to any one of (1) to (3), wherein the (meth) acrylic acid ester copolymer (B) has a weight average molecular weight of 50,000 to 150,000.
(5) The rubber modification according to any one of (1) to (4), wherein the graft copolymer (C) has a volume average particle size (Dv) of 0.25 to 0.60 μm. Styrenic resin composition.
(6) The glass transition temperature (Tg) of the acid anhydride group-containing copolymer (A) is observed only in a temperature range of 110 to 150 ° C., (1) to (5) The rubber-modified styrenic resin composition according to any one of the above.
(7) The rubber-modified styrenic resin composition as described in any one of (1) to (6), wherein the polymerization mode of the acid anhydride group-containing copolymer (A) is bulk polymerization or solution polymerization object.
(8) Polymerization of the acid anhydride group-containing copolymer (A) leads to the total amount of the monomer compound for deriving the aromatic vinyl monomer unit and the (meth) acrylic acid ester monomer unit. To the mixed liquid mainly consisting of a part of the charged amount of the monomer compound for deriving the unsaturated dicarboxylic anhydride monomer unit and the unsaturated dicarboxylic anhydride monomer The rubber-modified styrenic polymer according to any one of (1) to (7), which is a polymer obtained by polymerizing the remainder of the monomer compound for deriving the body unit while being divided or continuously added. Resin composition.
(9) The rubber according to any one of (1) to (8), wherein the aromatic vinyl monomer unit of the acid anhydride group-containing copolymer (A) is derived from styrene. Modified styrenic resin composition.
(10) The (meth) acrylic acid ester monomer unit of the acid anhydride group-containing copolymer (A) is derived from methyl methacrylate, (1) to (9) any one of items A rubber-modified styrene-based resin composition.
(11) The unsaturated dicarboxylic acid anhydride monomer unit of the acid anhydride group-containing copolymer (A) is derived from maleic acid anhydride, any of (1) to (10) 2. The rubber-modified styrenic resin composition according to claim 1.
(12) Any of (1) to (11), wherein the (meth) acrylic acid ester copolymer (B) comprises a (meth) acrylic acid ester monomer unit and an aromatic vinyl monomer unit. 2. A rubber-modified styrenic resin composition according to item 1.
(13) The rubber-modified styrenic resin composition according to any one of (1) to (12), wherein the diene rubber-like polymer (a) of the graft copolymer (C) is polybutadiene. .
(14) A molded article comprising the rubber-modified styrenic resin composition according to any one of (1) to (13).

According to the present invention, it is possible to obtain a transparent rubber-modified styrenic resin composition having excellent impact resistance, light transmittance, surface hardness, heat resistance, hue, and moldability and a molded product thereof.

Hereinafter, modes for carrying out the present invention will be described.

This embodiment is composed of an acid anhydride group-containing copolymer (A), a (meth) acrylic ester copolymer (B), and a graft copolymer (C). The present invention relates to a rubber-modified styrenic resin composition having excellent balance of surface hardness, heat resistance, hue, and moldability and a molded product thereof.

(I) Acid anhydride group-containing copolymer (A)
The acid anhydride group-containing copolymer (A) is an aromatic vinyl monomer unit of 15 to 80% by mass, a (meth) acrylic acid ester monomer unit of 15 to 80% by mass, an unsaturated dicarboxylic acid anhydride. It is a copolymer resin composition comprising 5 to 30% by mass of a monomer unit.
The acid anhydride group-containing copolymer (A) is a monomer compound for deriving an aromatic vinyl monomer unit (hereinafter referred to as an aromatic vinyl monomer), a (meth) acrylic acid ester monomer Monomer compound for inducing body units (hereinafter referred to as (meth) acrylic acid ester monomers) and monomer compounds for inducing unsaturated dicarboxylic acid anhydride monomer units (hereinafter referred to as unsaturated) It is obtained by polymerizing a dicarboxylic acid anhydride monomer).

Specific examples of aromatic vinyl monomers that can be used in the acid anhydride group-containing copolymer (A) include styrene, α-methylstyrene, p-methylstyrene, o-methylstyrene, and m-methylstyrene. , Arbitrary aromatic vinyl monomers such as ethyl styrene, pt-butyl styrene, chlorostyrene, bromostyrene and the like. Of these, styrene and α-methylstyrene are preferable, and styrene is most preferable, from the viewpoint of maintaining good compatibility with the (meth) acrylic acid ester copolymer (B). These aromatic vinyl monomers may be used alone or in combination of two or more.

Specific examples of (meth) acrylic acid ester monomers that can be used in the acid anhydride group-containing copolymer (A) include acrylic acid esters such as methyl acrylate, ethyl acrylate, and butyl acrylate, methyl methacrylate, Arbitrary (meth) acrylic acid ester-type monomers, such as methacrylic acid ester, such as ethyl methacrylate and butyl methacrylate, are mentioned. Among them, methyl methacrylate is most preferable from the viewpoint of maintaining good light transmittance and surface hardness of the rubber-modified styrene resin composition. These (meth) acrylic acid ester monomers may be used alone or in combination of two or more.

Specific examples of unsaturated dicarboxylic acid anhydride monomers that can be used in the acid anhydride group-containing copolymer (A) include maleic acid anhydride, itaconic acid anhydride, citraconic acid anhydride, and aconitic acid anhydride. And any unsaturated dicarboxylic acid anhydride monomer. Of these, maleic anhydride is most preferable from the viewpoint of compatibility with the (meth) acrylic acid ester copolymer (B) and imparting heat resistance to the rubber-modified styrene resin composition. These unsaturated dicarboxylic acid anhydride monomers may be used alone or in combination of two or more.

Furthermore, the acid anhydride group-containing copolymer (A) may contain monomer units derived from other monomer compounds as long as the purpose is not impaired. Other monomer compounds include vinyl cyanide compounds such as acrylonitrile, methacrylonitrile, and fumaronitrile, vinyl ester compounds such as vinyl acetate and vinyl benzoate, vinyl ether compounds such as methyl vinyl ether, ethyl vinyl ether, and propio vinyl ether. It is done. These monomer compounds may be used alone or in combination of two or more, and the total content is preferably 5% by mass or less.

The composition ratio of the monomer unit in the acid anhydride group-containing copolymer (A) of the present invention is 15 to 80% by mass of an aromatic vinyl monomer unit, and a (meth) acrylic acid ester monomer unit. 15 to 80% by mass and 5 to 30% by mass of unsaturated dicarboxylic acid anhydride monomer units. More preferably, the aromatic vinyl monomer unit is 25 to 70% by mass, the (meth) acrylic acid ester monomer unit is 25 to 70% by mass, and the unsaturated dicarboxylic acid anhydride monomer unit is 5 to 20% by mass. is there.

If the aromatic vinyl monomer unit in the acid anhydride group-containing copolymer (A) is 15% by mass or 25% by mass or more, the moldability of the rubber-modified styrenic resin composition is favorably maintained. If it is 80 mass% or 70 mass% or less, the surface hardness of the rubber-modified styrenic resin composition can be maintained satisfactorily.

If the (meth) acrylic acid ester monomer unit in the acid anhydride group-containing copolymer (A) is 15 mass% or 25 mass% or more, the surface hardness of the rubber-modified styrene resin composition is favorably maintained. If it is 80% by mass or 70% by mass or less, the hue of the rubber-modified styrenic resin composition can be favorably maintained.

If the unsaturated dicarboxylic acid anhydride monomer unit in the acid anhydride group-containing copolymer (A) is 5% by mass or more, the heat resistance of the rubber-modified styrenic resin composition can be favorably maintained. If it is 30% by mass or 20% by mass or less, the impact strength of the rubber-modified styrenic resin composition can be favorably maintained.

The weight average molecular weight (Mw) of the acid anhydride group-containing copolymer (A) is preferably in the range of 50,000 to 250,000, and more preferably in the range of 60,000 to 200,000. In particular, it is more preferably in the range of 80,000 to 150,000.

If the weight average molecular weight (Mw) of the acid anhydride group-containing copolymer (A) is 50,000 or more, the heat resistance of the rubber-modified styrenic resin composition can be maintained well. Moreover, if it is 250,000 or less, the moldability of a rubber-modified styrene resin composition can be maintained satisfactorily.

The weight average molecular weight (Mw) of the acid anhydride group-containing copolymer (A) is arbitrarily adjusted by changing the polymerization conditions, that is, the types and amounts of the polymerization initiator and the chain transfer agent, and the temperature during the polymerization. It is possible.
In addition, the weight average molecular weight (Mw) of the acid anhydride group-containing copolymer (A) is a weight average molecular weight (Mw) in terms of polystyrene measured by GPC (gel permeation chromatography).

The glass transition temperature (Tg) of the acid anhydride group-containing copolymer (A) is not particularly limited, but it is preferably observed only in a temperature range of 110 to 155 ° C.

The polymerization mode of the acid anhydride group-containing copolymer (A) is not particularly limited, but examples thereof include bulk polymerization, solution polymerization, suspension polymerization, bulk-suspension polymerization, and emulsion polymerization. A known method can be employed. Among these, solution polymerization is most preferable from the viewpoint of easy handling of the polymerization solution.

The solvent used in the solution polymerization of the acid anhydride group-containing copolymer (A) is not particularly limited, but from the viewpoint of availability and solubility of the acid anhydride group-containing copolymer (A), For example, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and acetophenone, ethers such as tetrahydrofuran and 1,4-dioxane, aromatic hydrocarbons such as benzene, toluene, xylene and chlorobenzene, N, N-dimethylformamide, dimethyl sulfoxide , N-methyl-2-pyrrolidone and the like, and among them, methyl ethyl ketone and methyl isobutyl ketone are particularly preferable because of the ease of solvent removal during devolatilization recovery of the acid anhydride group-containing copolymer (A). The amount of these solvents added is not particularly limited, but is preferably in the range of 20 to 200 parts by mass, particularly in the range of 80 to 140 parts by mass with respect to 100 parts by mass of the total amount of monomer compounds. More preferably.

The polymerization process of the acid anhydride group-containing copolymer (A) is not particularly limited, but known processes such as a batch polymerization method, a semi-batch polymerization method, and a continuous polymerization method can be employed. Among them, it is preferable to employ a batch polymerization method because an acid anhydride group-containing copolymer (A) having a well-defined composition can be easily obtained.

The polymerization method of the acid anhydride group-containing copolymer (A) is not particularly limited, but radical polymerization is preferred from the viewpoint that it can be produced with high productivity by a simple process, and any radical polymerization is possible. Initiator can be used

The radical polymerization initiator used for the polymerization of the acid anhydride group-containing copolymer (A) is not particularly limited, but known examples include azo compounds, organic peroxides, inorganic peroxides, and hydrogen peroxide. The peroxide can be used. Among them, from the viewpoint of easy reaction control and availability, azo compounds such as azobisisobutyronitrile, azobiscyclohexanecarbonitrile, azobismethylpropionitrile, azobismethylbutyronitrile, benzoyl peroxide, t-butylperoxybenzoate, 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, t-butylperoxyisopropyl monocarbonate, t-butylperoxy-2-ethylhexanoate It is preferable to employ organic peroxides such as di-t-butyl peroxide, dicumyl peroxide, ethyl-3,3-di- (t-butylperoxy) butyrate.

The radical polymerization initiator used for the polymerization of the acid anhydride group-containing copolymer (A) may be used alone or in combination of two or more. From the viewpoint of polymerization reaction rate and polymerization rate control, those conventionally used in the production of conventional styrenic resins are preferred. Specifically, azo compounds having a 10-hour half-life temperature of 70 to 120 ° C. and organic peroxides are preferred. It is preferable to use an oxide.

Although there is no restriction | limiting in particular about the usage-amount of a radical polymerization initiator, It is preferable to use 0.1-1.5 mass parts with respect to 100 mass parts of total amounts of a monomer compound, and especially 0.1-1. More preferably, 0 part by mass is used.

If the amount of the radical polymerization initiator used is 0.1 parts by mass or more with respect to 100 parts by mass of the total amount of monomer compounds, a sufficient polymerization rate can be obtained, so that good productivity can be maintained. . If the amount of the radical polymerization initiator used is 1.5 parts by mass or less with respect to 100 parts by mass of the total amount of the monomer compounds, the polymerization rate can be suppressed, and the reaction control becomes easy. The molecular weight control of the copolymer (A) can be facilitated.

An arbitrary chain transfer agent may be used for the polymerization of the acid anhydride group-containing copolymer (A). The chain transfer agent to be used is not particularly limited, but specifically, from the viewpoint of availability, ease of molecular weight control, and the like, specifically, n-dodecyl mercaptan, t-dodecyl mercaptan, and 2,4-diphenyl-4- Chain transfer agents such as methyl-1-pentene can be used. In addition, about a chain transfer agent, you may use independently, but you may use 2 or more types together.

The amount of the chain transfer agent used is not particularly limited as long as the target molecular weight of the acid anhydride group-containing copolymer (A) can be obtained. It is preferable to use 1 to 0.8 parts by mass, and it is particularly preferable to use 0.15 to 0.5 parts by mass with respect to 100 parts by mass of the total amount of monomer compounds. If the usage-amount of a chain transfer agent is 0.1 mass part or more and 0.8 mass part or less, the target molecular weight of an acid anhydride group containing copolymer (A) can be obtained easily.

In the polymerization of the acid anhydride group-containing copolymer (A), the aromatic vinyl monomer, (meth) acrylic acid ester monomer, and unsaturated dicarboxylic acid anhydride monomer are all in the initial stage of polymerization. It can also be charged and polymerized. However, in this case, since the alternating copolymerization of the aromatic vinyl monomer and the unsaturated dicarboxylic anhydride monomer is strong, the copolymer contains many unsaturated dicarboxylic anhydride monomer units. May be generated. In order to obtain a copolymer having a uniform composition throughout the polymerization, an aromatic vinyl monomer, a (meth) acrylic acid ester monomer, and an unsaturated dicarboxylic acid anhydride system are used. It is preferable to carry out the polymerization while charging a part of the monomer at the initial stage of polymerization and adding the remainder of the unsaturated dicarboxylic acid anhydride monomer in portions or continuously. In this way, an acid anhydride group-containing copolymer (A) having a uniform composition can be obtained.

The polymerization temperature of the acid anhydride group-containing copolymer (A) is not particularly limited, but the initial polymerization temperature is preferably 80 to 110 ° C., and 110 ° C. to 150 ° C. in order to improve the polymerization rate in the late polymerization stage. It is preferable that
Moreover, it is preferable to adjust the addition rate of the unsaturated dicarboxylic acid anhydride monomer so that the addition is completed when the conversion rate of the aromatic vinyl monomer reaches 80 to 95%. Furthermore, by adjusting the polymerization time and the amount of polymerization initiator, the polymerization rate of the unsaturated dicarboxylic acid anhydride monomer can be increased to 99.9% or more, and the acid anhydride group-containing copolymer excellent in hue. Since (A) is obtained, a rubber-modified styrenic resin composition obtained using the same can be obtained with a good hue.

The method for removing volatile components such as the solvent and unreacted monomer used in the polymerization of the acid anhydride group-containing copolymer (A) is not particularly limited, and a known method can be used. A method using a type screw type extruder is preferred. As a devolatilization condition when using a vent type screw type extruder, it is preferable that the resin temperature is 310 to 340 ° C. and devolatilization is performed under a reduced pressure of −92 kPaG or less. By increasing the resin temperature under reduced pressure under vacuum, non-polymerizable solvents and unreacted monomers are likely to volatilize, and if the resin temperature is kept below 340 ° C, an acid anhydride group-containing copolymer (A) Since the depolymerization due to thermal degradation of the resin can be suppressed, and an acid anhydride group-containing copolymer (A) excellent in hue can be obtained, even in the rubber-modified styrene resin composition obtained using this, the hue Can be obtained. In addition, about the adjustment method of resin temperature, it can carry out by adjusting the screw rotation speed of an extruder, or cylinder temperature.

Any radical scavenger may be used for the purpose of preventing thermal degradation of the acid anhydride group-containing copolymer (A) and maintaining a good hue. The radical scavenger is not particularly limited, and examples thereof include antioxidants such as phenol compounds, organic phosphorus compounds, organic sulfur compounds, and amine compounds. These radical scavengers may be used alone or in combination of two or more. These radical scavengers receive a significant thermal history in the process of devolatilizing volatile components in styrene-maleimide copolymers with a vent-type screw extruder, so as to maintain their functions as radical scavengers. In particular, a compound having heat resistance and heat stability is preferred. For example, a radical scavenger having a 1% heat loss temperature exceeding 300 ° C. is even more preferable. The radical scavenger is preferably added to the polymerization product after polymerization. If added before or during polymerization, the polymerization rate may decrease.

(Ii) (Meth) acrylic ester copolymer (B)
The (meth) acrylic acid ester-based copolymer (B) has (meth) acrylic acid ester-based monomer units of 70 to 99% by mass, aromatic vinyl monomer units and alkyl groups having 1 to 8 carbon atoms. It is a copolymer resin composition consisting of 30 to 1% by mass of one or more monomer units selected from the group consisting of acrylic acid esters.
The (meth) acrylic acid ester copolymer (B) includes a monomer compound (hereinafter referred to as a (meth) acrylic acid ester monomer) that derives a (meth) acrylic acid ester monomer unit. One or more selected from the group consisting of a monomer compound for deriving an aromatic vinyl monomer unit and a monomer compound for deriving an acrylate ester monomer unit having 1 to 8 carbon atoms of an alkyl group This monomer compound is obtained by polymerizing by a known method.

Specific examples of (meth) acrylic acid ester monomers that can be used for the (meth) acrylic acid ester copolymer (B) include acrylic acid esters such as methyl acrylate, ethyl acrylate, and butyl acrylate, and methyl Arbitrary (meth) acrylic acid ester-type monomers, such as methacrylates, such as methacrylate, ethyl methacrylate, and butyl methacrylate, are mentioned. Among them, methyl methacrylate is most preferable from the viewpoint of maintaining good light transmittance and surface hardness of the rubber-modified styrene resin composition. These (meth) acrylic acid ester monomers may be used alone or in combination of two or more.

Specific examples of the aromatic vinyl monomer that can be used for the (meth) acrylic acid ester copolymer (B) include styrene, α-methylstyrene, p-methylstyrene, o-methylstyrene, m- Arbitrary aromatic vinyl monomers, such as methylstyrene, ethylstyrene, pt-butylstyrene, chlorostyrene, bromostyrene, etc. are mentioned. Among them, styrene and α-methylstyrene are preferable from the viewpoint of maintaining good compatibility between the heat resistance of the rubber-modified styrene resin composition and the compatibility with the acid anhydride group-containing copolymer (A). Most preferably. These aromatic vinyl monomers may be used alone or in combination of two or more.

Furthermore, the (meth) acrylic acid ester-based copolymer (B) may contain a monomer unit derived from another monomer compound as long as the object of the invention is not impaired. Other monomer compounds include vinyl cyanide compounds such as acrylonitrile, methacrylonitrile and fumaronitrile, vinyl ester compounds such as vinyl acetate and vinyl benzoate, vinyl ether compounds such as methyl vinyl ether, ethyl vinyl ether and propio vinyl ether, N- Examples thereof include N-substituted maleimide monomers such as phenylmaleimide and N-methylmaleimide. These monomer compounds may be used singly or in combination of two or more, and the total content is preferably 5% by mass or less.

The constitutional ratio of the monomer units in the (meth) acrylic acid ester copolymer (B) of the present invention is preferably 70 to 99% by mass of (meth) acrylic acid ester monomer units, aromatic vinyl. It is 1-30 mass% of system monomer units. More preferably, they are 85-99 mass% of (meth) acrylic acid ester monomer units and 1-15 mass% of aromatic vinyl monomer units. If the (meth) acrylate monomer unit in the (meth) acrylate copolymer (B) is 70% by mass or more, the surface hardness of the rubber-modified styrene resin composition is favorably maintained. Can do.

The weight average molecular weight (Mw) of the (meth) acrylic acid ester copolymer (B) is not particularly limited, but is preferably 50,000 to 150,000.

When the weight average molecular weight (Mw) of the (meth) acrylic acid ester copolymer (B) is 50,000 or more, the heat resistance of the rubber-modified styrene resin composition can be favorably maintained. Moreover, if it is 150,000 or less, the moldability of a rubber-modified thermal styrene resin composition can be maintained good.

The weight average molecular weight (Mw) of the (meth) acrylic acid ester copolymer (B) can be arbitrarily set by changing the polymerization conditions, that is, the types and amounts of the polymerization initiator and the chain transfer agent, and the temperature during the polymerization. It is possible to adjust.
In addition, the weight average molecular weight (Mw) of the (meth) acrylic acid ester copolymer (B) is a weight average molecular weight (Mw) in terms of polystyrene measured by GPC (gel permeation chromatography).

The polymerization mode of the (meth) acrylic acid ester copolymer (B) is not particularly limited, but for example, bulk polymerization, solution polymerization, suspension polymerization, bulk-suspension polymerization, emulsion polymerization, and the like. A known method such as the above can be adopted. Among them, since the (meth) acrylic acid ester copolymer (B) having a low impurity content and good hue is obtained, the hue is also good in the rubber-modified styrene resin composition obtained by using this. From the viewpoint, bulk polymerization or solution polymerization is preferable. Furthermore, the polymerization process of the (meth) acrylic acid ester copolymer (B) may be any of batch polymerization, semi-batch polymerization, and continuous polymerization, but from the viewpoint of productivity. The continuous polymerization method is preferred.

When continuous polymerization is adopted as the polymerization mode of the (meth) acrylic acid ester copolymer (B), the reactor is composed of a fully mixed reactor (CSTR) and a piston flow reactor (PFR). The structure connected in series in order is preferable. It should be noted that one or more CSTRs and PFRs may be connected according to the purpose, and these may be connected, but the number of CSTRs is preferably 1 to 2, and more preferably 1 in particular. . The number of PRFs is preferably 1 to 3, and more preferably 1 in particular.

When the solution polymerization of the (meth) acrylic acid ester copolymer (B) is adopted, the solvent to be used is not particularly limited, but from the viewpoint of availability, solubility of the copolymer, etc., for example, acetone, Ketones such as methyl ethyl ketone, methyl isobutyl ketone and acetophenone, ethers such as tetrahydrofuran and 1,4-dioxane, aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene and chlorobenzene, N, N-dimethylformamide, dimethyl sulfoxide, There are solvents such as N-methyl-2-pyrrolidone, among which toluene and ethylbenzene are particularly preferable from the viewpoint of solubility of the (meth) acrylic acid ester copolymer (B) in the solvent. The amount of these solvents to be added is not particularly limited, but is preferably in the range of 1 to 30 parts by mass, particularly in the range of 5 to 25 parts by mass with respect to 100 parts by mass of the total amount of the monomer compounds. More preferably.

The polymerization method of the (meth) acrylic acid ester copolymer (B) is not particularly limited, but radical polymerization is preferable from the viewpoint that it can be produced with high productivity by a simple process. Can use radical polymerization initiator

The radical polymerization initiator used for the polymerization of the (meth) acrylic acid ester copolymer (B) is not particularly limited. For example, azo compounds, organic peroxides, inorganic peroxides, hydrogen peroxide, etc. It is possible to employ known peroxides. Among them, from the viewpoint of easy reaction control and availability, azo compounds such as azobisisobutyronitrile, azobiscyclohexanecarbonitrile, azobismethylpropionitrile, azobismethylbutyronitrile, benzoyl peroxide, t-butylperoxybenzoate, 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, t-butylperoxyisopropyl monocarbonate, t-butylperoxy-2-ethylhexanoate It is preferable to employ organic peroxides such as di-t-butyl peroxide, dicumyl peroxide, ethyl-3,3-di- (t-butylperoxy) butyrate.

In the polymerization of the (meth) acrylic acid ester copolymer (B), the radical polymerization initiator may be used alone or in combination of two or more. From the viewpoint of polymerization reaction rate and polymerization rate control, those conventionally used in the production of conventional styrenic resins are preferred. Specifically, azo compounds having a 10-hour half-life temperature of 70 to 120 ° C. and organic peroxides are preferred. It is preferable to use an oxide.

Although there is no restriction | limiting in particular about the usage-amount of a radical polymerization initiator, It is preferable to use 0.001-0.1 mass part with respect to 100 mass parts of total amounts of a monomer compound, and especially 0.002-0. It is more preferable to use 03 parts by mass.

If the amount of the radical polymerization initiator used is 0.001 part by mass or 0.002 parts by mass or more with respect to 100 parts by mass of the total amount of the monomer compounds, a sufficient polymerization rate can be obtained, and thus good productivity. Can be maintained. If the amount of the radical polymerization initiator used is 0.1 parts by mass or 0.03 parts by mass or less with respect to 100 parts by mass of the total amount of monomer compounds, the polymerization rate can be suppressed and the reaction control becomes easy. The molecular weight control of the (meth) acrylic acid ester copolymer (B) can be facilitated.

An arbitrary chain transfer agent may be used for the polymerization of the (meth) acrylic acid ester copolymer (B). The chain transfer agent to be used is not particularly limited, but specifically, from the viewpoint of availability, ease of molecular weight control, and the like, specifically, n-dodecyl mercaptan, t-dodecyl mercaptan, and 2,4-diphenyl-4- Chain transfer agents such as methyl-1-pentene can be used. In addition, about a chain transfer agent, you may use independently, but you may use 2 or more types together.

The amount of the chain transfer agent used is not particularly limited as long as the target molecular weight of the (meth) acrylic ester copolymer (B) can be obtained, but with respect to 100 parts by mass of the total amount of monomer compounds. It is preferable to use 0.05-2.0 mass parts, and it is more preferable to use 0.2-0.8 mass parts especially with respect to 100 mass parts of total amounts of a monomer compound. If the usage-amount of a chain transfer agent is 0.05 mass part or more and 2.0 mass parts or less, the target molecular weight of a (meth) acrylic acid ester type copolymer (B) can be obtained easily.

Although there is no restriction | limiting in particular about the polymerization temperature of a (meth) acrylic acid ester type copolymer (B), When employ | adopting continuous polymerization, the reaction temperature in CSTR has preferable 110 to 160 degreeC, Especially 120 degreeC. More preferably, it is in the range of ~ 140 ° C. Moreover, the reaction temperature in PFR is preferably 120 ° C to 170 ° C, and more preferably in the range of 130 ° C to 150 ° C. In this way, it is possible to obtain a (meth) acrylic acid ester copolymer (B) that is easy to control and has a uniform composition.

The method for removing volatile components such as the solvent and unreacted monomer used for the polymerization of the (meth) acrylic acid ester copolymer (B) is not particularly limited, and a known method can be used. Among these, a method using a devolatilization tank is preferable. When using a devolatilization tank, the temperature of the molten resin is preferably maintained at 260 ° C. or lower, and more preferably 240 ° C. or lower. If the resin temperature is suppressed to 260 ° C. or 240 ° C. or lower, depolymerization due to thermal deterioration of the (meth) acrylate copolymer (B) can be suppressed, and the (meth) acrylate ester excellent in hue Since the copolymer (B) is obtained, a rubber-modified styrenic resin composition obtained by using the copolymer (B) can be obtained with a good hue. In addition, about the adjustment method of resin temperature, it can carry out by the temperature adjustment of a devolatilization tank.

Any radical scavenger may be used for the purpose of preventing thermal deterioration during processing of the (meth) acrylic acid ester copolymer (B) and maintaining a good hue. The radical scavenger is not particularly limited, and examples thereof include antioxidants such as phenol compounds, organic phosphorus compounds, organic sulfur compounds, and amine compounds. These radical scavengers may be used alone or in combination of two or more. These radical scavengers receive a significant thermal history in the process of devolatilizing volatile components in styrene-maleimide copolymers with a vent-type screw extruder, so as to maintain their functions as radical scavengers. In particular, a compound having heat resistance and heat stability is preferred. For example, a radical scavenger having a 1% heat loss temperature exceeding 300 ° C. is even more preferable. The radical scavenger is preferably added to the polymerization product after polymerization. If added before or during polymerization, the polymerization rate may decrease.

(Iii) Graft copolymer (C)
Graft copolymer (C) is diene rubbery polymer (a) 40-60% by mass, styrene-methacrylic ester copolymer comprising styrene monomer units and methacrylate monomer units. (B) A graft copolymer comprising 40 to 60% by mass. The graft copolymer (C) is a copolymer containing a branched structure in which a styrene-methacrylate copolymer is bonded to a diene rubber-like polymer. Furthermore, the graft copolymer (C) includes a styrene-methacrylic acid ester copolymer that is not grafted to the diene rubber-like polymer, which is by-produced during the graft polymerization. The graft copolymer (C) is obtained by polymerizing a (meth) acrylic acid ester monomer and a styrene monomer by a known method in the presence of a diene rubber-like polymer. .

The diene rubbery polymer used in the graft copolymer (C) is a conjugated diene rubber such as polybutadiene, butadiene-styrene copolymer, butadiene-acrylonitrile copolymer, polyisoprene, styrene-isoprene copolymer, And hydrogenated products thereof, and these can be used alone or in combination of two or more. Among these, from the viewpoint of imparting impact strength, conjugated diene rubbers containing butadiene as a main component such as polybutadiene, butadiene-styrene copolymer, and butadiene-acrylonitrile copolymer are preferable, and among these, polybutadiene is used. This is particularly preferred.

Specific examples of (meth) acrylic acid ester monomers that can be used in the graft copolymer (C) include acrylic acid esters such as methyl acrylate, ethyl acrylate, and butyl acrylate, methyl methacrylate, ethyl methacrylate, and butyl. Arbitrary (meth) acrylic acid ester-type monomers, such as methacrylic acid esters, such as methacrylate, are mentioned. Among these, methyl methacrylate is most preferable from the viewpoint of maintaining good heat resistance of the rubber-modified styrene resin composition. These (meth) acrylic acid ester monomers may be used alone or in combination of two or more.

Specific examples of the styrene monomer that can be used in the graft copolymer (C) include styrene, α-methylstyrene, p-methylstyrene, o-methylstyrene, m-methylstyrene, ethylstyrene, p- Arbitrary styrenic monomers, such as t-butyl styrene, chloro styrene, bromo styrene, are mentioned. Above all, from the viewpoint of maintaining good heat resistance of the rubber-modified styrene resin composition and compatibility with the acid anhydride group-containing copolymer (A) and the (meth) acrylic acid ester copolymer (B), styrene , Α-methylstyrene is preferable, and styrene is most preferable. These aromatic vinyl monomers may be used alone or in combination of two or more.

Furthermore, the graft copolymer (C) may contain a monomer unit derived from another monomer compound as long as the object of the invention is not impaired. Other monomer compounds include vinyl cyanide compounds such as acrylonitrile, methacrylonitrile and fumaronitrile, vinyl ester compounds such as vinyl acetate and vinyl benzoate, vinyl ether compounds such as methyl vinyl ether, ethyl vinyl ether and propio vinyl ether, N- Examples thereof include N-substituted maleimide monomers such as phenylmaleimide and N-methylmaleimide. These monomer compounds may be used singly or in combination of two or more, and the total content is preferably 5% by mass or less.

The ratio of the diene rubber-like polymer and the styrene-methacrylic acid ester copolymer constituting the graft copolymer (C) of the present invention is 40 to 60% by mass of the diene rubber polymer, styrene-methacrylic acid ester. The copolymer is 40 to 60% by mass. More preferably, they are 45-60 mass% of rubber-like polymers and 40-55 mass% of aromatic vinyl- (meth) acrylic acid ester copolymers. When the diene rubber polymer is 40% by mass or more, the impact resistance of the rubber-modified styrene resin composition can be maintained satisfactorily. If the diene rubber polymer is 60% by mass or less, the heat resistance and molding processability of the rubber-modified styrene resin composition can be maintained well.

The volume average particle diameter (Dv) of the graft copolymer (C) is preferably 0.25 to 0.60 μm. In particular, the thickness is more preferably in the range of 0.30 to 0.45 μm. If the volume average particle diameter (Dv) is 0.25 μm or more, the impact resistance of the rubber-modified styrenic resin composition can be maintained well. If the volume average particle diameter (Dv) is 0.60 μm or less, the light transmittance and molding processability of the rubber-modified styrenic resin composition can be maintained satisfactorily.

The volume average particle diameter (Dv) of the graft copolymer (C) is a diene rubber-like polymer constituting the polymerization conditions, that is, the volume average rubber particle diameter of the rubber-like polymer and the graft copolymer (C). It can be arbitrarily adjusted by changing the ratio of the aromatic vinyl- (meth) acrylic acid ester copolymer.
The volume average particle diameter (Dv) of the graft copolymer (C) is a volume-based median diameter measured by a light scattering particle size distribution measuring device.

The polymerization mode of the graft copolymer (C) is not particularly limited, but known methods such as a bulk polymerization method, a solution polymerization method, a suspension polymerization method, a bulk-suspension polymerization method, and an emulsion polymerization method are used. Can be adopted. Among these, the emulsion polymerization method is preferable from the viewpoint of imparting impact resistance to the rubber-modified styrene resin composition.

The polymerization method of the graft copolymer (C) is not particularly limited, but radical polymerization is preferable from the viewpoint that it can be produced with a simple process with high productivity, and any radical polymerization initiator is used. it can

As radical initiators used in the graft copolymer (C), azo compounds such as azobisisobutyronitrile and azobiscyclohexanecarbonitrile, benzoyl peroxide, t-butylperoxybenzoate, t-butylperoxy- Organic peroxides such as 2-ethylhexanoate, di-t-butyl peroxide, dicumyl peroxide, ethyl-3,3-di- (t-butylperoxy) butyrate, hydrogen peroxide, persulfate Inorganic peroxides such as potassium and ammonium persulfate can be used. Among them, it is preferable to use inorganic peroxides and organic peroxides. Ferrous sulfate and the like together with inorganic peroxides and organic peroxides. It is more preferable to use a redox initiator in combination with a reducing agent. In the polymerization of the graft copolymer (C), the radical polymerization initiator may be used alone, but two or more kinds may be used in combination.

Although there is no restriction | limiting in particular about the usage-amount of a radical polymerization initiator, It is preferable to use 0.1-0.5 mass part with respect to 100 mass parts of total amounts of a monomer compound, Especially 0.5-3. It is more preferable to use 5 parts by mass.

The amount of the radical polymerization initiator used is 0.001 part by mass with respect to 100 parts by mass of the total amount of the diene rubber-like polymer and the monomer compound composed of the aromatic vinyl monomer and the (meth) acrylate monomer. If it is 1 part by mass or more, a sufficient polymerization rate can be obtained, so that good productivity can be maintained. When the amount of the radical polymerization initiator used is 3.5 parts by mass or less with respect to 100 parts by mass of the total amount of monomer compounds, the polymerization rate can be suppressed and the reaction control becomes easy.

An arbitrary chain transfer agent may be used for the polymerization of the graft copolymer (C). The chain transfer agent to be used is not particularly limited, but specifically, from the viewpoint of availability, ease of molecular weight control, and the like, specifically, n-dodecyl mercaptan, t-dodecyl mercaptan, and 2,4-diphenyl-4- Chain transfer agents such as methyl-1-pentene can be used. The chain transfer agent may be used alone or in combination of two or more.

The polymerization temperature of the graft copolymer (C) is not particularly limited, but the reaction temperature when employing emulsion polymerization is 50 ° C. or higher from the viewpoint of increasing the polymerization reaction rate and maintaining good productivity. It is preferable that the temperature is 55 ° C. or higher. Further, from the viewpoint of reducing the amount of coagulum or deposits generated in the polymerization can and maintaining good productivity, it is preferably 98 ° C. or less, and particularly preferably 90 ° C. or less.

(Iv) Compounding composition of rubber-modified styrene resin composition The compounding composition of the rubber-modified styrene resin composition is 10 to 90 parts by mass (excluding 90 parts by mass) of the acid anhydride group-containing copolymer (A), It consists of (meth) acrylic acid ester copolymer (B) 0-80 parts by mass (excluding 0 parts by mass) and graft copolymer (C) 10-35 parts by mass [provided that (A), (B ), (C) total is 100 parts by mass]. If the blending composition is within this range, a rubber-modified styrene resin composition and its molded product can be obtained that are excellent in balance of impact resistance, light transmission, surface hardness, heat resistance, hue, and moldability. Further, particularly preferred blending composition of the rubber-modified styrene resin composition is 20-80 parts by mass of the acid anhydride group-containing copolymer (A), 0-60 mass of the (meth) acrylic acid ester copolymer (B). Parts, graft copolymer (C) 20-30 parts by mass.

If the acid anhydride group-containing copolymer (A) is 10 parts by mass or more, the heat resistance of the blended composition of the rubber-modified styrenic resin composition can be maintained well. Moreover, if it is 90 mass parts or less, the impact resistance and surface hardness of the compounding composition of a rubber-modified styrene resin composition can be maintained favorable.

If the (meth) acrylic acid ester copolymer (B) is 80 parts by mass or 60 parts by mass or less, the heat resistance of the blended composition of the rubber-modified styrenic resin composition can be maintained well.

If the graft copolymer (C) is 10 parts by mass or more, the impact resistance of the rubber-modified styrenic resin composition can be maintained satisfactorily. Moreover, if it is 35 mass parts or less, the surface hardness and molding processability of a rubber-modified styrene resin composition can be favorably maintained.

There are no particular restrictions on the order of mixing the components of the acid anhydride group-containing copolymer (A), (meth) acrylic acid ester copolymer (B), and graft copolymer (C). And a method of mixing two components in advance and then mixing with one other component. Such mixing can be performed by a conventionally known method.

As a method of mixing all the components at the same time, using a uniaxial or biaxial melt extruder, an acid anhydride group-containing copolymer (A), a (meth) acrylic ester copolymer (B), The graft copolymer (C) and various additives can be added and melt mixed. As a method of mixing with other one component, for example, an acid anhydride group-containing copolymer (A) and a (meth) acrylic acid ester copolymer (B) are used with a single-screw and a twin-screw melt extruder. Can be melt-mixed with the graft copolymer (C) again using a uniaxial and biaxial melt extruder. In this case as well, various additives can be added. Can be melt mixed.

As extrusion conditions when melt-kneading using a twin screw extruder, the resin temperature is preferably 190 to 260 ° C, more preferably 200 to 240 ° C. The resin temperature can be adjusted by adjusting the cylinder temperature, screw rotation speed, and raw material feed amount.

If necessary, the rubber-modified styrenic resin composition includes a heat resistant stabilizer such as a hindered phenol compound, a lactone compound, a phosphorus compound, and a sulfur compound, a light resistant stabilizer such as a hindered amine compound and a benzotriazole compound, You may mix | blend additives, such as a lubricant, a plasticizer, a coloring agent, an antistatic agent, and mineral oil. It is preferable that the compounding quantity is less than 1 mass part with respect to 100 mass parts of resin compositions for optical molded objects.

As mentioned above, although embodiment of this invention was described, these are illustrations of this invention and can also employ | adopt various structures other than the above.

Hereinafter, although detailed content is demonstrated using an Example, this invention is not limited to a following example.

[Experimental example (A) -1]
In an autoclave having a volume of about 25 liters equipped with a stirrer, 35 parts by mass of styrene, 60 parts by mass of methyl methacrylate, 0.50 parts by mass of maleic anhydride, 0.23 parts by mass of t-butylperoxyisopropyl monooxycarbonate, n -0.30 part by mass of dodecyl mercaptan and 7.2 parts by mass of methyl ethyl ketone were charged, the inside of the system was replaced with nitrogen gas, and then the temperature was raised to 95 ° C. Next, a solution obtained by dissolving 4.8 parts by mass of maleic anhydride and 0.13 parts by mass of t-butylperoxy 2-ethylhexanoate in 64.8 parts by mass of methyl ethyl ketone was continuously added over 5 hours. However, after maintaining at 95 ° C. for 4 hours, the temperature was raised to 120 ° C. over 2 hours and reacted at 120 ° C. for 0.5 hour. The obtained reaction liquid was supplied to a vent type screw extruder, and volatile components were removed to obtain a pellet-like acid anhydride group-containing copolymer (A) -1. The composition ratio of the monomer units is 35% by mass of styrene monomer units, 60% by mass of methyl methacrylate monomer units, 5% by mass of maleic anhydride monomer units, Mw is 182,000, and glass transition. The temperature was 111 ° C. and the refractive index was 1.528.

[Experimental example (A) -2]
In an autoclave having a volume of about 25 liters equipped with a stirrer, 41 parts by mass of styrene, 48 parts by mass of methyl methacrylate, 1.1 parts by mass of maleic anhydride, 0.20 parts by mass of t-butylperoxyisopropyl monooxycarbonate, n -After 0.28 parts by mass of dodecyl mercaptan and 7.2 parts by mass of methyl ethyl ketone were charged and the system was replaced with nitrogen gas, the temperature was raised to 95 ° C. Next, a solution prepared by dissolving 9.9 parts by mass of maleic anhydride and 0.13 parts by mass of t-butylperoxy 2-ethylhexanoate in 64.8 parts by mass of methyl ethyl ketone was continuously added over 5 hours. However, after maintaining at 95 ° C. for 4 hours, the temperature was raised to 120 ° C. over 2 hours and reacted at 120 ° C. for 0.5 hour. The obtained reaction liquid was supplied to a vent type screw extruder, and volatile components were removed to obtain a pellet-like acid anhydride group-containing copolymer (A) -2. The composition ratio of the monomer units is 41% by mass of styrene monomer units, 48% by mass of methyl methacrylate monomer units, 11% by mass of maleic anhydride monomer units, Mw is 200,000, and glass transition. The temperature was 120 ° C. and the refractive index was 1.533.

[Experimental example (A) -3]
In an autoclave having a volume of about 25 liters equipped with a stirrer, 70 parts by mass of styrene, 15 parts by mass of methyl methacrylate, 1.5 parts by mass of maleic anhydride, 0.20 parts by mass of t-butylperoxyisopropyl monooxycarbonate, n -After 0.28 parts by mass of dodecyl mercaptan and 7.2 parts by mass of methyl ethyl ketone were charged and the system was replaced with nitrogen gas, the temperature was raised to 95 ° C. Next, a solution obtained by dissolving 13.5 parts by mass of maleic anhydride and 0.13 parts by mass of t-butylperoxy 2-ethylhexanoate in 64.8 parts by mass of methyl ethyl ketone was continuously added over 5 hours. However, after maintaining at 95 ° C. for 4 hours, the temperature was raised to 120 ° C. over 2 hours and reacted at 120 ° C. for 0.5 hour. The obtained reaction liquid was supplied to a vent type screw extruder, and volatile components were removed to obtain a pellet-like acid anhydride group-containing copolymer (A) -3. The composition ratio of the monomer units is 70% by mass of styrene monomer units, 15% by mass of methyl methacrylate monomer units, and 15% by mass of maleic anhydride monomer units, and Mw is 200,000. The temperature was 126 ° C. and the refractive index was 1.561.

[Experimental example (A) -4]
In an autoclave having a volume of about 25 liters equipped with a stirrer, 59 parts by mass of styrene, 26 parts by mass of methyl methacrylate, 1.5 parts by mass of maleic anhydride, 0.22 parts by mass of t-butylperoxyisopropyl monooxycarbonate, n -0.30 part by mass of dodecyl mercaptan and 7.2 parts by mass of methyl ethyl ketone were charged, the inside of the system was replaced with nitrogen gas, and then the temperature was raised to 95 ° C. Next, a solution obtained by dissolving 13.5 parts by mass of maleic anhydride and 0.13 parts by mass of t-butylperoxy 2-ethylhexanoate in 64.8 parts by mass of methyl ethyl ketone was continuously added over 5 hours. However, after maintaining at 95 ° C. for 4 hours, the temperature was raised to 120 ° C. over 2 hours and reacted at 120 ° C. for 0.5 hour. The obtained reaction solution was supplied to a vent type screw type extruder to remove volatile components, thereby obtaining a pellet-like acid anhydride group-containing copolymer (A) -4. The composition ratio of the monomer units is 59% by mass of styrene monomer units, 26% by mass of methyl methacrylate monomer units, 15% by mass of maleic anhydride monomer units, Mw is 195,000, and glass transition. The temperature was 126 ° C. and the refractive index was 1.550.

[Experimental example (A) -5]
In an autoclave having a volume of about 25 liters equipped with a stirrer, 45 parts by mass of styrene, 40 parts by mass of methyl methacrylate, 1.5 parts by mass of maleic anhydride, 0.10 parts by mass of t-butylperoxyisopropyl monooxycarbonate, n -0.20 part by mass of dodecyl mercaptan and 7.2 parts by mass of methyl ethyl ketone were charged, and the system was replaced with nitrogen gas, and then the temperature was raised to 95 ° C. Next, a solution prepared by dissolving 13.5 parts by mass of maleic anhydride and 0.10 parts by mass of t-butylperoxy 2-ethylhexanoate in 64.8 parts by mass of methyl ethyl ketone was continuously added over 5 hours. However, after maintaining at 95 ° C. for 4 hours, the temperature was raised to 120 ° C. over 2 hours and reacted at 120 ° C. for 0.5 hour. The obtained reaction liquid was supplied to a vent type screw type extruder, and volatile components were removed to obtain a pellet-like acid anhydride group-containing copolymer (A) -5. The composition ratio of the monomer units is 45% by mass of styrene monomer units, 40% by mass of methyl methacrylate monomer units, 15% by mass of maleic anhydride monomer units, Mw is 245,000, and glass transition. The temperature was 129 ° C. and the refractive index was 1.536.

[Experimental example (A) -6]
In an autoclave having a volume of about 25 liters equipped with a stirrer, 45 parts by mass of styrene, 40 parts by mass of methyl methacrylate, 1.5 parts by mass of maleic anhydride, 0.20 parts by mass of t-butylperoxyisopropyl monooxycarbonate, n -0.30 part by mass of dodecyl mercaptan and 7.2 parts by mass of methyl ethyl ketone were charged, the inside of the system was replaced with nitrogen gas, and then the temperature was raised to 95 ° C. Next, a solution obtained by dissolving 13.5 parts by mass of maleic anhydride and 0.13 parts by mass of t-butylperoxy 2-ethylhexanoate in 64.8 parts by mass of methyl ethyl ketone was continuously added over 5 hours. However, after maintaining at 95 ° C. for 4 hours, the temperature was raised to 120 ° C. over 2 hours and reacted at 120 ° C. for 0.5 hour. The obtained reaction liquid was supplied to a vent type screw extruder, and volatile components were removed to obtain a pellet-like acid anhydride group-containing copolymer (A) -6. The composition ratio of the C monomer unit is 45% by mass of the styrene monomer unit, 40% by mass of the methyl methacrylate monomer unit, 15% by mass of the maleic anhydride monomer unit, Mw is 204,000, glass The transition temperature was 128 ° C. and the refractive index was 1.536.

[Experimental example (A) -7]
In an autoclave having a volume of about 25 liters equipped with a stirrer, 45 parts by mass of styrene, 40 parts by mass of methyl methacrylate, 1.5 parts by mass of maleic anhydride, 0.25 parts by mass of t-butylperoxyisopropyl monooxycarbonate, n -0.35 parts by mass of dodecyl mercaptan and 7.2 parts by mass of methyl ethyl ketone were charged, the inside of the system was replaced with nitrogen gas, and then the temperature was raised to 95 ° C. Next, a solution prepared by dissolving 13.5 parts by mass of maleic anhydride and 0.17 parts by mass of t-butylperoxy 2-ethylhexanoate in 64.8 parts by mass of methyl ethyl ketone was continuously added over 5 hours. However, after maintaining at 95 ° C. for 4 hours, the temperature was raised to 120 ° C. over 2 hours and reacted at 120 ° C. for 0.5 hour. The obtained reaction liquid was supplied to a vent type screw extruder, and volatile components were removed to obtain a pellet-like acid anhydride group-containing copolymer (A) -7. The composition ratio of the monomer units is 45% by mass of styrene monomer units, 40% by mass of methyl methacrylate monomer units, 15% by mass of maleic anhydride monomer units, Mw is 168,000, and glass transition. The temperature was 127 ° C. and the refractive index was 1.536.

[Experimental example (A) -8]
In an autoclave having a volume of about 25 liters equipped with a stirrer, 45 parts by mass of styrene, 40 parts by mass of methyl methacrylate, 1.5 parts by mass of maleic anhydride, 0.25 parts by mass of t-butylperoxyisopropyl monooxycarbonate, n -0.50 part by mass of dodecyl mercaptan and 7.2 parts by mass of methyl ethyl ketone were charged and the system was replaced with nitrogen gas, and then the temperature was raised to 95 ° C. Next, a solution prepared by dissolving 13.5 parts by mass of maleic anhydride and 0.17 parts by mass of t-butylperoxy 2-ethylhexanoate in 64.8 parts by mass of methyl ethyl ketone was continuously added over 5 hours. However, after maintaining at 95 ° C. for 4 hours, the temperature was raised to 120 ° C. over 2 hours and reacted at 120 ° C. for 0.5 hour. The obtained reaction liquid was supplied to a vent type screw extruder, and volatile components were removed to obtain a pellet-like acid anhydride group-containing copolymer (A) -8. The composition ratio of the monomer units is 45% by mass of styrene monomer units, 40% by mass of methyl methacrylate monomer units, 15% by mass of maleic anhydride monomer units, Mw is 102,000, and glass transition. The temperature was 127 ° C. and the refractive index was 1.536.

[Experimental example (A) -9]
In an autoclave having a volume of about 25 liters equipped with a stirrer, 28 parts by mass of styrene, 40 parts by mass of methyl methacrylate, 3.5 parts by mass of maleic anhydride, 0.20 parts by mass of t-butylperoxyisopropyl monooxycarbonate, n -After charging 0.30 part by mass of dodecyl mercaptan and 21.6 parts by mass of methyl ethyl ketone and replacing the system with nitrogen gas, the temperature was raised to 95 ° C. Next, a solution obtained by dissolving 12 parts by mass of styrene, 16.5 parts by mass of maleic anhydride, 0.20 parts by mass of t-butylperoxy 2-ethylhexanoate in 50.4 parts by mass of methyl ethyl ketone is taken over 5 hours. While continuously added, the mixture was maintained at 95 ° C. for 4 hours, then heated to 120 ° C. over 2 hours, and reacted at 120 ° C. for 0.5 hour. The obtained reaction liquid was supplied to a vent type screw extruder, and volatile components were removed to obtain a pellet-like acid anhydride group-containing copolymer (A) -9. The composition ratio of the monomer units is 40% by mass of styrene monomer units, 40% by mass of methyl methacrylate monomer units, 20% by mass of maleic anhydride monomer units, Mw is 200,000, and glass transition. The temperature was 136 ° C. and the refractive index was 1.532.

[Experimental example (A) -10]
In an autoclave having a volume of about 25 liters equipped with a stirrer, 25 parts by mass of styrene, 20 parts by mass of methyl methacrylate, 5.0 parts by mass of maleic anhydride, 0.20 parts by mass of t-butylperoxyisopropyl monooxycarbonate, n -After charging 0.30 part by mass of dodecyl mercaptan and 21.6 parts by mass of methyl ethyl ketone and replacing the system with nitrogen gas, the temperature was raised to 95 ° C. Next, a solution obtained by dissolving 25 parts by mass of styrene, 25.0 parts by mass of maleic anhydride, and 0.20 parts by mass of t-butylperoxy 2-ethylhexanoate in 50.4 parts by mass of methyl ethyl ketone is taken over 5 hours. While continuously added, the mixture was maintained at 95 ° C. for 4 hours, then heated to 120 ° C. over 2 hours, and reacted at 120 ° C. for 0.5 hour. The obtained reaction liquid was supplied to a vent type screw extruder, and volatile components were removed to obtain a pellet-like acid anhydride group-containing copolymer (A) -10. The composition ratio of the monomer units is 50% by mass of styrene monomer units, 20% by mass of methyl methacrylate monomer units, 30% by mass of maleic anhydride monomer units, Mw is 200,000, and glass transition. The temperature was 154 ° C. and the refractive index was 1.537.

[Experimental example (A) -11]
In an autoclave having a volume of about 25 liters equipped with a stirrer, 15 parts by mass of styrene, 80 parts by mass of methyl methacrylate, 0.1 part by mass of maleic anhydride, 0.20 part by mass of t-butylperoxyisopropyl monooxycarbonate, n -0.30 part by mass of dodecyl mercaptan and 7.2 parts by mass of methyl ethyl ketone were charged, the inside of the system was replaced with nitrogen gas, and then the temperature was raised to 95 ° C. Next, a solution prepared by dissolving 4.9 parts by mass of maleic anhydride and 0.13 parts by mass of t-butylperoxy 2-ethylhexanoate in 64.8 parts by mass of methyl ethyl ketone was continuously added over 5 hours. However, after maintaining at 95 ° C. for 4 hours, the temperature was raised to 120 ° C. over 2 hours and reacted at 120 ° C. for 0.5 hour. The obtained reaction liquid was supplied to a vent type screw type extruder, and volatile components were removed to obtain a pellet-like acid anhydride group-containing copolymer (A) -11. The composition ratio of the monomer unit is 15% by mass of styrene monomer unit, 80% by mass of methyl methacrylate monomer unit, 5% by mass of maleic anhydride monomer, Mw is 200,000, and glass transition temperature. Was 112 ° C. and the refractive index was 1.508.

[Experimental example (A) -12]
In an autoclave having a volume of about 25 liters equipped with a stirrer, 75 parts by mass of styrene, 15 parts by mass of methyl methacrylate, 1.0 part by mass of maleic anhydride, 0.20 part by mass of t-butylperoxyisopropyl monooxycarbonate, n -0.27 parts by mass of dodecyl mercaptan and 7.2 parts by mass of methyl ethyl ketone were charged, the inside of the system was replaced with nitrogen gas, and then the temperature was raised to 95 ° C. Next, a solution prepared by dissolving 9.0 parts by mass of maleic anhydride and 0.14 parts by mass of t-butylperoxy 2-ethylhexanoate in 64.8 parts by mass of methyl ethyl ketone was continuously added over 5 hours. However, after maintaining at 95 ° C. for 4 hours, the temperature was raised to 120 ° C. over 2 hours and reacted at 120 ° C. for 0.5 hour. The obtained reaction liquid was supplied to a vent type screw type extruder to remove volatile components, thereby obtaining a pellet-like acid anhydride group-containing copolymer (A) -12. The composition ratio of the monomer units is 75% by mass of styrene monomer units, 15% by mass of methyl methacrylate monomer units, 10% by mass of maleic anhydride monomer units, Mw is 200,000, and glass transition. The temperature was 117 ° C. and the refractive index was 1.567.

[Experimental example (A) -13]
In an autoclave having a volume of about 25 liters equipped with a stirrer, 45 parts by mass of styrene, 40 parts by mass of methyl methacrylate, 1.5 parts by mass of maleic anhydride, 0.10 parts by mass of t-butylperoxyisopropyl monooxycarbonate, n -0.05 part by weight of dodecyl mercaptan and 7.2 parts by weight of methyl ethyl ketone were charged, the inside of the system was replaced with nitrogen gas, and then the temperature was raised to 95 ° C. Next, a solution prepared by dissolving 13.5 parts by mass of maleic anhydride and 0.07 parts by mass of t-butylperoxy 2-ethylhexanoate in 64.8 parts by mass of methyl ethyl ketone was continuously added over 5 hours. However, after maintaining at 95 ° C. for 4 hours, the temperature was raised to 120 ° C. over 2 hours and reacted at 120 ° C. for 0.5 hour. The obtained reaction liquid was supplied to a vent type screw extruder, and volatile components were removed to obtain a pellet-like acid anhydride group-containing copolymer (A) -2. The composition ratio of the monomer units is 45% by mass of styrene monomer units, 40% by mass of methyl methacrylate monomer units, 15% by mass of maleic anhydride monomer units, Mw is 305,000, and glass transition. The temperature was 130 ° C. and the refractive index was 1.536.

[Experimental example (A) -14]
In an autoclave having a volume of about 25 liters equipped with a stirrer, 45 parts by mass of styrene, 40 parts by mass of methyl methacrylate, 1.5 parts by mass of maleic anhydride, 0.25 parts by mass of t-butylperoxyisopropyl monooxycarbonate, n -0.65 parts by mass of dodecyl mercaptan and 7.2 parts by mass of methyl ethyl ketone were charged, and the system was replaced with nitrogen gas, and then the temperature was raised to 95 ° C. Next, a solution prepared by dissolving 13.5 parts by mass of maleic anhydride and 0.25 parts by mass of t-butylperoxy 2-ethylhexanoate in 64.8 parts by mass of methyl ethyl ketone was continuously added over 5 hours. However, after maintaining at 95 ° C. for 4 hours, the temperature was raised to 120 ° C. over 2 hours and reacted at 120 ° C. for 0.5 hour. The obtained reaction liquid was supplied to a vent type screw type extruder, and volatile matter was removed to obtain a pellet-like acid anhydride group-containing copolymer (A) -14. The composition ratio of the monomer units is 45% by mass of styrene monomer units, 40% by mass of methyl methacrylate monomer units, 15% by mass of maleic anhydride monomer units, Mw is 65,000, glass transition The temperature was 124 ° C. and the refractive index was 1.536.

[Experimental example (A) -15]
In an autoclave having a volume of about 25 liters equipped with a stirrer, 15 parts by mass of styrene, 15 parts by mass of methyl methacrylate, 4.0 parts by mass of maleic anhydride, 0.20 parts by mass of t-butylperoxyisopropyl monooxycarbonate, n -After charging 0.30 part by mass of dodecyl mercaptan and 21.6 parts by mass of methyl ethyl ketone and replacing the system with nitrogen gas, the temperature was raised to 95 ° C. Next, a solution obtained by dissolving 32 parts by mass of styrene, 34.0 parts by mass of maleic anhydride, and 0.20 parts by mass of t-butylperoxy 2-ethylhexanoate in 50.4 parts by mass of methyl ethyl ketone is taken over 5 hours. While continuously added, the mixture was maintained at 95 ° C. for 4 hours, then heated to 120 ° C. over 2 hours, and reacted at 120 ° C. for 0.5 hour. The obtained reaction liquid was supplied to a vent type screw extruder, and volatile components were removed to obtain a pellet-like acid anhydride group-containing copolymer (A) -15. The composition ratio of the monomer units is 47% by mass of styrene monomer units, 15% by mass of methyl methacrylate monomer units, 38% by mass of maleic anhydride monomer units, Mw is 200,000, and glass transition. The temperature was 171 ° C. and the refractive index was 1.532.

[Experimental example (A) -16]
In an autoclave having a volume of about 25 liters equipped with a stirrer, 68 parts by mass of styrene, 30 parts by mass of methyl methacrylate, 0.20 parts by mass of maleic anhydride, 0.23 parts by mass of t-butylperoxyisopropyl monooxycarbonate, n -0.30 part by mass of dodecyl mercaptan and 7.2 parts by mass of methyl ethyl ketone were charged, the inside of the system was replaced with nitrogen gas, and then the temperature was raised to 95 ° C. Next, a solution prepared by dissolving 1.8 parts by weight of maleic anhydride and 0.13 parts by weight of t-butylperoxy 2-ethylhexanoate in 64.8 parts by weight of methyl ethyl ketone was continuously added over 5 hours. However, after maintaining at 95 ° C. for 4 hours, the temperature was raised to 120 ° C. over 2 hours and reacted at 120 ° C. for 0.5 hour. The obtained reaction liquid was supplied to a vent type screw extruder, and volatile components were removed to obtain a pellet-like acid anhydride group-containing copolymer (A) -16. The composition ratio of the monomer units is 68% by mass of styrene monomer units, 30% by mass of methyl methacrylate monomer units, 2% by mass of maleic anhydride monomer units, Mw is 200,000, and glass transition. The temperature was 105 ° C. and the refractive index was 1.562.

[Experimental example (A) -17]
In an autoclave having a volume of about 25 liters equipped with a stirrer, 85 parts by weight of methyl methacrylate, 0.13 parts by weight of t-butylperoxyisopropyl monooxycarbonate, 0.30 parts by weight of n-dodecyl mercaptan, 7.2 parts by weight of methyl ethyl ketone Was replaced with nitrogen gas, and the temperature was raised to 95 ° C. Next, a solution in which 10 parts by mass of styrene, 5.0 parts by mass of maleic anhydride and 0.13 parts by mass of t-butylperoxy 2-ethylhexanoate were dissolved in 64.8 parts by mass of methyl ethyl ketone was taken over 5 hours. While continuously added, the mixture was maintained at 95 ° C. for 4 hours, then heated to 120 ° C. over 2 hours, and reacted at 120 ° C. for 0.5 hour. The obtained reaction liquid was supplied to a vent type screw extruder, and volatile components were removed to obtain a pellet-like acid anhydride group-containing copolymer (A) -17. The composition ratio of the monomer units is 10% by mass of styrene monomer units, 85% by mass of methyl methacrylate monomer units, 5% by mass of maleic anhydride monomer units, Mw is 200,000, and glass transition. The temperature was 112 ° C. and the refractive index was 1.503.

[Experimental example (A) -18]
In an autoclave having a volume of about 25 liters equipped with a stirrer, 85 parts by mass of styrene, 3.0 parts by mass of maleic anhydride, 0.05 parts by mass of t-butylperoxyisopropyl monooxycarbonate, 0.05 parts of n-dodecyl mercaptan Part by mass and 7.2 parts by mass of methyl ethyl ketone were charged and the system was replaced with nitrogen gas, and then the temperature was raised to 95 ° C. Next, a solution prepared by dissolving 12.0 parts by mass of maleic anhydride and 0.2 parts by mass of t-butylperoxy 2-ethylhexanoate in 64.8 parts by mass of methyl ethyl ketone was continuously added over 5 hours. However, after maintaining at 95 ° C. for 4 hours, the temperature was raised to 120 ° C. over 2 hours and reacted at 120 ° C. for 0.5 hour. The obtained reaction liquid was supplied to a vent type screw type extruder to remove volatile components, thereby obtaining a pellet-like acid anhydride group-containing copolymer (A) -18. The composition ratio of the monomer unit is 85% by mass of the styrene monomer unit and 15% by mass of the maleic anhydride monomer unit, the Mw is 305,000, the glass transition temperature is 125 ° C., and the refractive index is 1. 576.

[Experimental example (A) -19]
With reference to JP-A-62-207346, a styrene-maleic anhydride-N-phenylmaleimide copolymer resin was produced. The composition ratio of the monomer units is 47% by mass of styrene monomer units, 1% by mass of maleic anhydride monomer units, 52% by mass of N-phenylmaleimide monomer units, and Mw is 125,000. The glass transition temperature was 196 ° C. and the refractive index was 1.528.

The method for measuring the analytical value of the acid anhydride group-containing copolymer (A) is as follows.
(1) Constitution ratio of monomer units in acid anhydride group-containing copolymer (A) Composition ratio of methyl methacrylate / styrene calculated by pyrolysis gas chromatography method (I) and nuclear magnetic resonance absorption method ( It is calculated from the constituent ratio of methyl methacrylate / maleic anhydride calculated by II).

Pyrolysis gas chromatography (I)
The polymer was thermally decomposed at a furnace temperature of 450 ° C., and the decomposition gas was quantified by gas chromatography to determine the composition ratio of methyl methacrylate / styrene.

Nuclear magnetic resonance absorption (II)
NMR was measured under the following conditions, and the constituent ratio of methyl methacrylate / maleic anhydride was determined from the ratio of the integrated value of carbonyl carbon of methyl methacrylate and maleic anhydride.
Device name: AVANCE-300 (manufactured by BRUKER)
Measurement nuclide: C13
Temperature: 110 ° C
Concentration: 10% by mass
Solvent: DMSO-d6
Integration count: 10,000 times

(2) Weight average molecular weight (Mw) of anhydride group-containing copolymer (A)
It is a weight average molecular weight (Mw) in terms of polystyrene measured by GPC (gel permeation chromatography) under the following conditions.
Device name: SYSTEM-21 Shodex (manufactured by Showa Denko)
Column: 3 series PL gel MIXED-B Temperature: 40 ° C
Detection: Differential refractive index Solvent: Tetrahydrofuran Concentration: 2% by mass
Calibration curve: produced using standard polystyrene (PS) (manufactured by PL), and Mw was expressed in terms of polystyrene.

(3) Glass transition temperature of anhydride group-containing copolymer (A) Measured according to JIS K-7121 under the following conditions.
Device name: Robot DSC6200 manufactured by Seiko Instruments Inc.
Temperature increase rate: 10 ° C / min

(4) A molded product having a thickness of 2 mm was prepared by refractive index press molding of the anhydride group-containing copolymer (A) and measured using an Abbe refractometer (DR-M2) manufactured by Atago Co., Ltd.

Table 1 shows the analytical values of the anhydride group-containing copolymer (A).

[Experimental example (B) -1]
A 20-liter fully mixed continuous reaction tank equipped with a multi-stage paddle on a stirring blade, a 11-liter tower-type plug flow continuous reaction tank, and a flash-type devolatilization tank equipped with a preheater were connected in series. . 0.0073 parts by mass of t-butylperoxyisopropyl monocarbonate and 0.18 parts by mass of n-dodecyl mercaptan with respect to a solution composed of 83.5 parts by mass of methyl methacrylate, 4.5 parts by mass of styrene, and 12.0 parts by mass of ethylbenzene Parts were mixed to obtain a raw material solution. This raw material solution was supplied to a fully mixed continuous reaction tank controlled at a temperature of 125 ° C. at 3.9 kg / hour. The conversion rate at the fully mixed continuous reaction tank outlet was 36.8% by mass. Furthermore, the conversion rate at the outlet of the column type plug flow type continuous reaction vessel in which the polymerization solution was adjusted so as to have a gradient of 125 ° C. to 144 ° C. in the flow direction was 76.9% by mass. While heating this polymerization liquid with a preheater, it was introduced into a first devolatilization tank depressurized to 10.6 kPa, and a part of the unreacted monomer was removed at a tank internal temperature of 230 ° C. Further, while extracting this liquid with a gear pump, 9 g of water was added to the static mixer per hour and mixed, and then heated into a second devolatilization tank reduced to 1.3 kPa while being heated with a preheater. Unreacted monomer was removed at 0 ° C. This was extracted with a gear pump, extruded into a strand, and cut to obtain a pellet-like (meth) acrylic ester copolymer (B) -1.

[Experimental example (B) -2]
(B) -1 except that a monomer solution composed of 79.2% by weight of methyl methacrylate, 8.8% by weight of styrene, and 12.0% by weight of ethylbenzene was used to make 0.42 parts by weight of n-dodecyl mercaptan. In the same manner as above, a (meth) acrylic acid ester copolymer (B) -2 was obtained.

[Experimental example (B) -3]
(B) -1 except that a monomer solution composed of 79.2% by mass of methyl methacrylate, 8.8% by mass of styrene, and 12.0% by mass of ethylbenzene was used and the content was changed to 0.22 parts by mass of n-dodecyl mercaptan. In the same manner as above, a (meth) acrylic acid ester copolymer (B) -3 was obtained.

[Experimental example (B) -4]
(B) -1 except that a monomer solution composed of 79.2% by weight of methyl methacrylate, 8.8% by weight of styrene, and 12.0% by weight of ethylbenzene was used and 0.18 parts by weight of n-dodecyl mercaptan was used. (Meth) acrylic acid ester copolymer (B) -4 was obtained.

[Experimental example (B) -5]
(B) -1 except that a monomer solution composed of 79.2% by mass of methyl methacrylate, 8.8% by mass of styrene, and 12.0% by mass of ethylbenzene was used and the content was changed to 0.14 parts by mass of n-dodecyl mercaptan. In the same manner as above, a (meth) acrylic acid ester copolymer (B) -5 was obtained.

[Experimental example (B) -6]
(B) -1 except that a monomer solution composed of 70.0% by weight of methyl methacrylate, 18.0% by weight of styrene, and 12.0% by weight of ethylbenzene was used and the amount was 0.16 parts by weight of n-dodecyl mercaptan. (Meth) acrylic acid ester copolymer (B) -6 was obtained.

[Experimental example (B) -7]
(B) -1 except that a monomer solution composed of 61.6% by mass of methyl methacrylate, 26.4% by mass of styrene, and 12.0% by mass of ethylbenzene was used and the amount was 0.15 parts by mass of n-dodecyl mercaptan. In the same manner as above, a (meth) acrylic acid ester copolymer (B) -7 was obtained.

[Experimental example (B) -8]
(B) − except that a monomer solution composed of 75.5% by weight of methyl methacrylate, 4.5% by weight of ethyl acrylate, and 20.0% by weight of ethylbenzene was used and 0.42 parts by weight of n-dodecyl mercaptan was used. In the same manner as in Example 1, a (meth) acrylic acid ester copolymer (B) -8 was obtained.

[Experimental example (B) -9]
(B) − except that a monomer solution composed of 75.5% by mass of methyl methacrylate, 4.5% by mass of ethyl acrylate, and 20.0% by mass of ethylbenzene was used and 0.20 parts by mass of n-dodecyl mercaptan was used. In the same manner as in Example 1, a (meth) acrylic acid ester copolymer (B) -9 was obtained.

[Experimental example (B) -10]
(B) -1 except that a monomer solution composed of 79.2% by weight of methyl methacrylate, 8.8% by weight of styrene, and 12.0% by weight of ethylbenzene was used and the amount was changed to 0.55 parts by weight of n-dodecyl mercaptan. In the same manner as above, a (meth) acrylic acid ester copolymer (B) -10 was obtained.

[Experimental example (B) -11]
(B) -1 except that a monomer solution composed of 79.2% by weight of methyl methacrylate, 8.8% by weight of styrene, and 12.0% by weight of ethylbenzene was used and 0.08 parts by weight of n-dodecyl mercaptan was used. (Meth) acrylic acid ester copolymer (B) -11 was obtained.

[Experimental example (B) -12]
(B) -1 was carried out in the same manner as in (B) -1, except that a monomer solution composed of 80.0% by mass of methyl methacrylate and 20.0% by mass of ethylbenzene was used and 0.32 parts by mass of n-dodecyl mercaptan was used. A (meth) acrylic acid ester copolymer (B) -12 was obtained.

[Experimental example (B) -13]
(B) -1 except that a monomer solution composed of 40.0% by mass of methyl methacrylate, 48.0% by mass of styrene, and 12.0% by mass of ethylbenzene was used and 0.15 parts by mass of n-dodecyl mercaptan was used. In the same manner as above, a (meth) acrylic acid ester copolymer (B) -13 was obtained.

The method for measuring the analytical value of the (meth) acrylic acid ester copolymer (B) is as follows.
(5) Composition ratio of monomer units in (meth) acrylic ester copolymer (B) The polymer is thermally decomposed at a furnace temperature of 450 ° C., and the decomposition gas is quantified by gas chromatography, and methyl methacrylate is obtained. The composition ratio of / styrene / ethyl acrylate was determined.

(6) Weight average molecular weight (Mw) of (meth) acrylic acid ester copolymer (B)
It is a weight average molecular weight (Mw) in terms of polystyrene measured by GPC (gel permeation chromatography) under the following conditions.
Device name: SYSTEM-21 Shodex (manufactured by Showa Denko)
Column: 3 series PL gel MIXED-B Temperature: 40 ° C
Detection: Differential refractive index Solvent: Tetrahydrofuran Concentration: 2% by mass
Calibration curve: produced using standard polystyrene (PS) (manufactured by PL), and Mw was expressed in terms of polystyrene.

(7) Glass transition temperature of (meth) acrylic acid ester copolymer (B) Measured according to JIS K-7121 under the following conditions.
Device name: Robot DSC6200 manufactured by Seiko Instruments Inc.
Temperature increase rate: 10 ° C / min

(8) A molded product having a thickness of 2 mm was prepared by refractive index press molding of the (meth) acrylic acid ester copolymer (B), and measured using an Abbe refractometer (DR-M2) manufactured by Atago Co., Ltd. .

Table 2 shows analytical values of the (meth) acrylic acid ester copolymer (B).

[Experimental example (C) -1]
Butadiene latex (rubber particle size 0.30 μm) was weighed 12 kg in terms of solid content and transferred to an autoclave with a volume of 200 L, 98 kg of pure water was added, and the temperature was raised to 50 ° C. in a nitrogen stream while stirring. To this was added 2 kg of pure water in which 1.25 g of ferrous sulfate, 2.5 g of sodium ethylenediaminetetraacetate and 100 g of Rongalite were dissolved, and a mixture consisting of 10.6 kg of styrene, 37.4 kg of methyl methacrylate and 60 g of t-dodecyl mercaptan; A solution obtained by dispersing 120 g of diisopropylbenzene hydroperoxide in 8 kg of pure water containing 450 g of potassium oleate was continuously added separately over 6 hours. After completion of the addition, the temperature was raised to 70 ° C., 30 g of diisopropylbenzene hydroperoxide was further added, and the mixture was left for 2 hours to complete the polymerization. An antioxidant is added to the obtained emulsion, the solid content is diluted to 15% by mass with pure water, the temperature is raised to 60 ° C., dilute sulfuric acid is added with vigorous stirring, and salting out is performed. The temperature was raised to 90 ° C. to solidify, followed by dehydration, washing with water, and drying to obtain a powdered graft copolymer (C) -1.

[Experimental example (C) -2]
The same procedure as in (C) -1 was carried out except that butadiene latex (rubber particle size 0.30 μm) was 24 kg in terms of solid content, 86 kg of pure water, 7.9 kg of styrene, and 28.1 kg of methyl methacrylate. Combined (C) -2 was obtained.

[Experimental example (C) -3]
Butadiene latex (rubber particle diameter 0.17 μm) was weighed 31.5 kg in terms of solid content and transferred to an autoclave with a volume of 200 L, 78.5 kg of pure water was added, and the temperature was raised to 50 ° C. under nitrogen flow while stirring. . To this was added 2 kg of pure water in which 1.25 g of ferrous sulfate, 2.5 g of sodium ethylenediaminetetraacetate and 100 g of Rongalite were dissolved, and a mixture consisting of 6.3 kg of styrene, 22.2 kg of methyl methacrylate and 60 g of t-dodecyl mercaptan; A solution obtained by dispersing 120 g of diisopropylbenzene hydroperoxide in 8 kg of pure water containing 450 g of potassium oleate was continuously added separately over 6 hours. After completion of the addition, the temperature was raised to 70 ° C., 30 g of diisopropylbenzene hydroperoxide was further added, and the mixture was left for 2 hours to complete the polymerization. An antioxidant is added to the obtained emulsion, the solid content is diluted to 15% by mass with pure water, the temperature is raised to 60 ° C., dilute sulfuric acid is added with vigorous stirring, and salting out is performed. The mixture was heated to 90 ° C. and solidified, and then dehydrated, washed with water, and dried to obtain a powdered graft copolymer (C) -3.

[Experimental example (C) -4]
A graft copolymer (C) -4 was obtained in the same manner as in (C) -1, except that butadiene latex (rubber particle diameter of 0.30 μm) was used.

[Experimental example (C) -5]
A graft copolymer (C) -5 was obtained in the same manner as in (C) -1, except that butadiene latex (rubber particle diameter of 0.34 μm) was used.

[Experimental example (C) -6]
A graft copolymer (C) -6 was obtained in the same manner as in (C) -1, except that butadiene latex (rubber particle diameter of 0.42 μm) was used.

[Experimental example (C) -7]
A graft copolymer (C) -7 was obtained in the same manner as in (C) -1, except that butadiene latex (rubber particle diameter of 0.55 μm) was used.

[Experimental example (C) -8]
A graft copolymer (C) -8 was obtained in the same manner as (C) -1, except that butadiene latex (rubber particle diameter 0.72 μm) was used.

[Experimental example (C) -9]
36.0 kg of butadiene latex (rubber particle size 0.32 μm) was weighed and transferred to an autoclave with a volume of 200 L, 74.0 kg of pure water was added, and the temperature was raised to 50 ° C. under a nitrogen stream while stirring. . To this was added 2 kg of pure water in which 1.25 g of ferrous sulfate, 2.5 g of sodium ethylenediaminetetraacetate and 100 g of Rongalite were dissolved, and a mixture consisting of 5.3 kg of styrene, 18.7 kg of methyl methacrylate and 60 g of t-dodecyl mercaptan; A solution obtained by dispersing 120 g of diisopropylbenzene hydroperoxide in 8 kg of pure water containing 450 g of potassium oleate was continuously added separately over 6 hours. After completion of the addition, the temperature was raised to 70 ° C., 30 g of diisopropylbenzene hydroperoxide was further added, and the mixture was left for 2 hours to complete the polymerization. An antioxidant is added to the obtained emulsion, the solid content is diluted to 15% by mass with pure water, the temperature is raised to 60 ° C., dilute sulfuric acid is added with vigorous stirring, and salting out is performed. The mixture was heated to 90 ° C. and solidified, and then dehydrated, washed with water, and dried to obtain a powdered graft copolymer (C) -9.

[Experimental example (C) -10]
Butadiene latex (rubber particle size 0.32 μm) was weighed 42.0 kg in terms of solid content and transferred to an autoclave with a volume of 200 L, 68.0 kg of pure water was added, and the temperature was raised to 50 ° C. in a nitrogen stream while stirring. . To this was added 2 kg of pure water in which 1.25 g of ferrous sulfate, 2.5 g of sodium ethylenediaminetetraacetate and 100 g of Rongalite were dissolved, and a mixture consisting of 4.0 kg of styrene, 14.0 kg of methyl methacrylate and 60 g of t-dodecyl mercaptan; A solution obtained by dispersing 120 g of diisopropylbenzene hydroperoxide in 8 kg of pure water containing 450 g of potassium oleate was continuously added separately over 6 hours. After completion of the addition, the temperature was raised to 70 ° C., 30 g of diisopropylbenzene hydroperoxide was further added, and the mixture was left for 2 hours to complete the polymerization. An antioxidant is added to the obtained emulsion, the solid content is diluted to 15% by mass with pure water, the temperature is raised to 60 ° C., dilute sulfuric acid is added with vigorous stirring, and salting out is performed. The temperature was raised to 90 ° C. to solidify, followed by dehydration, washing with water and drying to obtain a powdered graft copolymer (C) -10.

The method for measuring the analytical value of the graft copolymer (C) is as follows.
(9) Constituent ratio of monomer units in acid anhydride group-containing copolymer (A) Polybutadiene amount measured by halogen addition method (III) and methyl calculated by pyrolysis gas chromatography method (IV) It is calculated from the constituent ratio of methacrylate / styrene.

Halogen addition method (III)
Dissolve the rubber-modified styrene resin in chloroform, add iodine monochloride to react the double bond in polybutadiene, add potassium iodide to change the remaining iodine monochloride to iodine, and reverse with sodium thiosulfate. By titrating, the amount of polybutadiene in the rubber-modified styrene resin was measured.

Pyrolysis gas chromatography (IV)
The polymer was thermally decomposed at a furnace temperature of 450 ° C., and the decomposition gas was quantified by gas chromatography to determine the composition ratio of methyl methacrylate / styrene.

(10) Volume average rubber particle diameter (Dv) of graft copolymer (C)
The volume average particle diameter (Dv) of the graft copolymer (C) is a volume-based median diameter measured with a light scattering type particle size distribution measuring device under the following conditions.
Device name: Coulter Multisizer LS230 (Beckman Coulter)
Solvent: N, N-dimethylformamide (DMF)
Concentration: 1% by mass
Pretreatment: N, N-dimethylformamide (DMF) is added to the graft copolymer (C) and stirred for 24 hours. After preparing a 1% by mass solution of the graft copolymer (C), an ultrasonic disperser A sample subjected to dispersion treatment for about 1 hour was used for measurement.

(11) A molded product having a thickness of 2 mm was prepared by refractive index press molding of the graft copolymer (C) and measured using an Abbe refractometer (DR-M2) manufactured by Atago Co., Ltd.

Table 3 shows analytical values of the graft copolymer (C).

Rubber-modified styrene-based resin composition An acid anhydride group-containing copolymer (A), a (meth) acrylic acid ester-based copolymer (B), and a graft copolymer (C) obtained by the above method, After mixing with a Henschel mixer, a pellet was prepared by melt-kneading using a twin screw extruder (TEM 35B manufactured by Toshiba Machine Co., Ltd., cylinder temperature 220 ° C.) to obtain a rubber-modified styrene resin composition. Tables 4 to 12 show blending ratios and measured values.

<Measurement method>
Various measurement values constituting the rubber-modified styrenic resin composition used in this example and methods for measuring each physical property value performed will be described below.

(12) Vicat softening point: A test piece having a size of 12.7 × 64 × 6.4 mm was molded at a cylinder temperature of 220 ° C. using an injection molding machine (IS-80CNV) manufactured by Toshiba Machine. Using this test piece, measurement was performed under the condition of a load of 49.0 N in accordance with JIS K 7206. If the Vicat softening point is 105 ° C. or higher, it can be determined that the heat resistance is good.

(13) Rockwell hardness: Test pieces having dimensions of 12.7 × 64 × 6.4 mm were molded at a cylinder temperature of 220 ° C. using an injection molding machine (IS-80CNV) manufactured by Toshiba Machine. Using this test piece, measurement was performed in accordance with JIS K 7202 (M scale).
If Rockwell hardness is 73 or more, it can be judged that surface hardness is favorable.

(13) Pencil hardness: A test piece having a size of 12.7 × 64 × 6.4 mm was molded at a cylinder temperature of 220 ° C. using an injection molding machine (IS-80CNV) manufactured by Toshiba Machine. Using this test piece, measurement was performed in accordance with JIS K 5600.
If the pencil hardness is F or more, it can be determined that the surface hardness is good.

(14) Charpy impact strength: A test piece having a size of 12.7 × 64 × 6.4 mm was formed at a cylinder temperature of 220 ° C. using Toshiba Machine Co., Ltd. (IS-80CNV). It measured based on JISK7111 using this test piece. If the Charpy impact strength is 5.0 kJ / m 2 or more, it can be determined that the impact resistance is good.

(15) Molding workability: Evaluated by MFR (melt mass flow rate). MFR (melt mass flow rate) was measured under the conditions of a temperature of 220 ° C. and a load of 10 kg in accordance with JIS K7210 using sample pellets.
If the MFR (melt mass flow rate) is 4.1 g / 10 min or more, it can be determined that the moldability is good.

(16) Total light transmittance: Measured according to ASTM D-1003 using a Nippon Denshoku Industries HAZE meter (NDH-2000). If the total light transmittance is 88% or more, it can be determined that the transparency is good.

Tables 4 to 12 show analytical values and measured values of the rubber-modified styrene resin composition.

Referring to Tables 4 to 12, in Examples 1 to 55, it can be seen that excellent results were obtained for all evaluation items.
In Comparative Example 1 in which the content of maleic anhydride in the copolymer (A) was too large, Rockwell hardness, pencil hardness, and Charpy impact strength were not sufficient.
In Comparative Example 2 in which the content of maleic anhydride in the copolymer (A) was too small, the Vicat softening point was not sufficient.
In Comparative Example 3 in which the styrene content of the copolymer (A) was too small, the total light transmittance was not sufficient.
In Comparative Example 4 in which the content of styrene in the copolymer (A) is too large, the Vicat softening point was not sufficient.
In Comparative Example 5 in which the content of styrene in the copolymer (B) is too large, the pencil hardness and the total light transmittance were not sufficient.
In Comparative Example 6 in which the content of the diene rubber-like polymer of the copolymer (C) was too small, the Charpy impact strength was not sufficient.
In Comparative Example 7 in which the content of the diene rubber-like polymer of the copolymer (C) was too large, the Vicat softening point, Rockwell hardness, and pencil hardness were not sufficient.
In Comparative Example 8 in which the copolymer (A) contains N-phenylmaleimide, Charpy impact strength, MFR, and total light transmittance were not sufficient.

  As described above, according to Examples 1 to 55, the transparent rubber-modified styrene resin composition of the present invention is excellent in impact resistance, light transmittance, surface hardness, heat resistance, hue, and moldability. I understood. And even if one of the copolymers (A) to (C) is out of the composition range of the present invention, it is proved by Comparative Examples 1 to 8 that the specific effect of the present invention cannot be obtained. .

According to the present invention, it is possible to obtain a transparent rubber-modified styrenic resin composition having excellent impact resistance, light transmittance, surface hardness, heat resistance, hue, and moldability and a molded product thereof. The molded product of the present invention can be suitably used for general sundries, electrical equipment, OA equipment housings and parts.

Claims (14)

10 to 90 parts by mass of the acid anhydride group-containing copolymer (A) (excluding 90 parts by mass), 0 to 80 parts by mass of the (meth) acrylic acid ester copolymer (B) (provided that 0 part by mass) Excluding), graft copolymer (C) rubber-modified styrenic resin composition comprising 10 to 35 parts by mass [however, the total of (A), (B) and (C) is 100 parts by mass].
Acid anhydride group-containing copolymer (A):
Copolymers comprising 15 to 80% by mass of aromatic vinyl monomer units, 15 to 80% by mass of (meth) acrylic acid ester monomer units, and 5 to 30% by mass of unsaturated dicarboxylic acid anhydride monomer units. Polymer resin composition.
(Meth) acrylic ester copolymer (B):
1 selected from the group consisting of 70 to 99% by mass of (meth) acrylic acid ester monomer units, aromatic vinyl monomer units, and alkyl ester monomer units having 1 to 8 carbon atoms in the alkyl group. A copolymer resin composition comprising 30 to 1% by mass of at least one monomer unit.
Graft copolymer (C):
Diene rubbery polymer (a) 40 to 60% by mass, styrene-methacrylic acid ester copolymer (b) composed of styrene monomer unit and methacrylic ester monomer unit (b) 40 to 60% by mass A graft copolymer. The refractive index with respect to d-line at 23 ° C. of the acid anhydride group-containing copolymer (A), (meth) acrylic acid ester copolymer (B), and graft copolymer (C) is defined as na, nb, nc,
The respective mass ratios of the acid anhydride group-containing copolymer (A), the (meth) acrylic ester copolymer (B), and the graft copolymer (C) in the rubber-modified styrene resin composition, respectively. , Wa, wb, wc (where wa + wb + wc = 1), the rubber-modified styrenic resin composition according to claim 1, wherein the following formulas 1 and 2 are satisfied.
Δn = | na × wa / (wa + wb) + nb × wb / (wa + wb) −nc | (Formula 1)
Δn ≦ 0.005 (Formula 2) The rubber-modified styrenic resin composition according to any one of claims 1 to 2, wherein the acid anhydride group-containing copolymer (A) has a weight average molecular weight (Mw) of 50,000 to 250,000. The rubber-modified styrene resin composition according to any one of claims 1 to 3, wherein the (meth) acrylic acid ester copolymer (B) has a weight average molecular weight of 50,000 to 150,000. The rubber-modified styrenic resin composition according to any one of claims 1 to 4, wherein the graft copolymer (C) has a volume average particle diameter (Dv) of 0.25 to 0.60 µm. object. 6. The glass transition temperature (Tg) of the acid anhydride group-containing copolymer (A) is observed only in a temperature range of 110 to 155 ° C. 6. The rubber-modified styrenic resin composition according to Item. The rubber-modified styrenic resin composition according to any one of claims 1 to 6, wherein the polymerization mode of the acid anhydride group-containing copolymer (A) is bulk polymerization or solution polymerization. Polymerization of the acid anhydride group-containing copolymer (A), the total amount of monomer compounds that derive aromatic vinyl monomer units, and the single amount that induces (meth) acrylate monomer units The unsaturated dicarboxylic acid anhydride monomer unit is mixed into the liquid mixture mainly composed of the total amount of the body compound and a part of the charged amount of the monomer compound for deriving the unsaturated dicarboxylic acid anhydride monomer unit. The rubber-modified styrenic resin composition according to any one of claims 1 to 7, wherein the rubber-modified styrenic resin composition is a polymer obtained by polymerizing the remainder of the monomer compound to be derived while being divided or continuously added. . The rubber-modified styrenic resin composition according to any one of claims 1 to 8, wherein the aromatic vinyl monomer unit of the acid anhydride group-containing copolymer (A) is styrene. object. The rubber-modified styrenic system according to any one of claims 1 to 9, wherein the (meth) acrylic acid ester monomer unit of the acid anhydride group-containing copolymer (A) is methyl methacrylate. Resin composition. The unsaturated dicarboxylic acid anhydride monomer unit of the acid anhydride group-containing copolymer (A) is maleic acid anhydride, according to any one of claims 1 to 10. Rubber-modified styrenic resin composition. The (meth) acrylic acid ester-based copolymer (B) is composed of a (meth) acrylic acid ester-based monomer unit and an aromatic vinyl-based monomer unit. A rubber-modified styrene-based resin composition. The rubber-modified styrenic resin composition according to any one of claims 1 to 12, wherein the diene rubber-like polymer (a) of the graft copolymer (C) is polybutadiene. A molded body comprising the rubber-modified styrenic resin composition according to any one of claims 1 to 13.