JP4112528B2 - Transparent rubber-modified styrene resin - Google Patents

Description

  The present invention relates to a transparent rubber-modified polystyrene resin, and more particularly to a transparent rubber-modified polystyrene resin composed of a copolymer particle continuous phase and a rubber particle dispersed phase composed of a rubber-like copolymer. The present invention relates to a transparent rubber-modified polystyrene resin containing a polyfunctional maleimide monomer in a phase. Such transparent rubber-modified polystyrene resin maintains good impact resistance and has excellent transparency and environmental stress crack resistance.

  Rubber-modified polystyrene-based resins have been widely applied to fields such as food containers, packaging materials, household products, electrical products, and office automation equipment as materials having good mechanical strength and moldability. However, since general rubber-modified polystyrene resins are opaque, they cannot be applied to molding transparent products.

In order to improve the strength and transparency of the resin, in known techniques such as Patent Document 1, Patent Document 2, Patent Document 3, Patent Document 4, etc., in the presence of a styrene-butadiene block copolymer, A method of copolymerizing styrene and methyl methacrylate has been proposed. However, with these methods, the transparency and mechanical strength of the resin can be improved, but the environmental stress crack resistance of the resin cannot be satisfied.
Japanese Patent Laid-Open No. 4-180907 JP-A-6-16744 JP-A-8-92329 JP-A-9-71621

  An object of the present invention is to provide a transparent rubber-modified polystyrene resin having excellent transparency and environmental stress crack resistance while maintaining impact resistance.

  As a result of intensive studies, the present inventors have found a transparent rubber-modified polystyrene resin composed of a rubber particle dispersed phase (A) and a copolymer continuous phase (B) comprising the following rubber-like copolymer.

  That is, the present invention relates to a transparent rubber-modified polystyrene resin, a rubber particle dispersed phase (A) comprising a rubbery copolymer, and (i-1) 20 to 70 parts by weight of a styrene monomer, 2) 30 to 80 parts by weight of a (meth) acrylic acid ester monomer, and (i-3) 0 to 40 parts by weight of another copolymerizable monomer, and (i-1), (i- A transparent rubber-modified polystyrene resin composed of a copolymer continuous phase (B) containing 0.0005 to 1.0 part by weight of a polyfunctional maleimide monomer with respect to a total of 100 parts by weight of 2) and (i-3) . Here, the polyfunctional maleimide monomer system remaining in the transparent rubber-modified styrene resin is 80 ppm or less, and the difference in refractive index between the copolymer continuous phase (B) and the rubber particle dispersed phase (A) is 0. 01 or less, and the rubber content in the transparent rubber-modified polystyrene resin is 1 to 40% by weight.

  The transparent rubber-modified styrenic resin has excellent impact resistance and excellent transparency and environmental stress crack resistance.

  The transparent rubber-modified polystyrene resin of the present invention is composed of a rubber particle dispersed phase (A) and a copolymer continuous phase (B) made of a rubbery copolymer. Here, the copolymer continuous phase (B) is (i-1) styrene monomer, (i-2) (meth) acrylate monomer, and (i-3) other copolymerizable It is comprised from a monomer and a polyfunctional maleimide-type monomer.

  The transparent rubber-modified polystyrene resin of the present invention has a polyfunctional maleimide monomer content remaining in the resin and a refractive index of the copolymer continuous phase (B) and the rubber particle dispersed phase (A). When the difference is in a specific range, the transparent rubber-modified polystyrene resin of the present invention has excellent transparency and environmental stress crack resistance while maintaining good impact resistance.

  The transparent rubber-modified polystyrene resin of the present invention comprises (i-1) 20 to 70 parts by weight of a styrene monomer, (i-2) 30 to 80 parts by weight of a (meth) acrylic acid ester monomer, and ( i-3) Polyfunctional maleimide with respect to 0 to 40 parts by weight of other copolymerizable monomers and a total of 100 parts by weight of the above (i-1), (i-2) and (i-3) It comprises a copolymer continuous phase (B) obtained by copolymerizing 0.0005 to 1.0 parts by weight of a system monomer and a rubber particle dispersed phase (A) comprising a rubbery copolymer.

  Here, the polyfunctional maleimide monomer remaining in the transparent rubber-modified styrene resin is 80 ppm or less.

  The difference in refractive index between the copolymer continuous phase (B) and the rubber particle dispersed phase (A) is 0.01 or less.

  The rubber content in the transparent rubber-modified polystyrene resin is 1 to 40% by weight.

The rubbery copolymer used in the present invention is obtained by anionic polymerization reaction of a styrene monomer, a diene monomer, and an appropriate amount of solvent using an organic lithium compound as a polymerization initiator in the presence of an organic solvent. Copolymer. The copolymer includes a block copolymer and a random copolymer, and a block copolymer is preferred. The rubbery copolymer preferably has a Mooney viscosity (ML _{1 + 4} ) of 20 to 80 and a 5 wt% styrene solution viscosity at 25 ° C. of 3 to 60 cps. The diene unit in the rubbery copolymer has a 1,2-vinyl structure content of 8% by weight or more in the diene unit, and a polystyrene block content of 5 to 35% by weight of the rubbery copolymer. % Is preferred. The rubbery copolymer may have any structure such as a homopolymer block structure, a partial random block structure, a tapered block structure, a linear structure, or a branched structure. The 1,2-vinyl structure in the present invention includes a structure of a substituted 1,2-vinyl group (for example, 2-methyl-1,2-vinyl group) in addition to the structure of a 1,2-vinyl group. Shall be included.

  In addition to the above block copolymer, the rubbery copolymer used in the present invention can be used in combination with 20 parts by weight or less of a diene non-block polymer with respect to 100 parts by weight of the block copolymer. Examples of such diene non-block polymers include diene homopolymers and diene copolymers (eg, butadiene-styrene random copolymers), and the structure of the diene moiety is a low-cis bond, which is generally a cis / vinyl bond. The typical weight composition range of the group is (30% to 40%) / (5% to 40%), while the 5% by weight styrene solution viscosity is 5 to 400 cps.

  The method for producing a rubbery copolymer in the present invention is a known technique, for example, US Pat. No. 2,975,160, US Pat. No. 3,094,514, US Pat. No. 3,135,716. Gazette, U.S. Pat. No. 3,244,664, U.S. Pat.No. 3,318,862, etc., and Japanese Patent Publication No. 48-875, Japanese Patent Publication No. 48-46691, Japanese Patent Publication No. 49-36957, It is described in detail in patents such as JP-A-55-40734 and JP-A-57-40513.

  Specific examples of the styrene monomer of the rubbery copolymer include styrene, α-methylstyrene, p-methylstyrene, m-methylstyrene, o-methylstyrene, ethylstyrene, 2,4-dimethyl. Examples include styrene, pt-butyl styrene, α-methyl-p-methyl styrene, bromostyrene, and the like. These can be used alone or in combination of two or more.

  Specific examples of the diene monomer of the rubbery copolymer include 1,3-butadiene, 2-methyl-1,3-butadiene, 2,3-dimethyl-1,3-butadiene, 1,3- Examples thereof include pentadiene and 1,3-hexadiene. These can be used individually or in mixture of 2 or more types. Of these, 1,3-butadiene or 2-methyl-1,3-butadiene is preferred.

  The organolithium compound used as a catalyst in the production of the rubbery copolymer used in the present invention refers to a compound having one or more lithium atoms in the molecule, and specific examples thereof include ethyllithium, n-pentyllithium, isopropyl. Lithium, n-butyllithium, s-butyllithium, t-butyllithium, hexyllithium, cyclohexyllithium, phenyllithium, benzyllithium, t-butyllithium, trimethylene-dilithium, tetramethylene-dilithium, butadiene-dilithium and pentadiene-dilithium These may be used alone or in combination of two or more.

  The polymerization rate when polymerizing the rubbery copolymer in the present invention, the content of 1,2-vinyl group, the reactivity ratio between the diene monomer and the styrene monomer, the randomized state, etc. It can be adjusted using polar compounds or randomizing agents. The polar compound or randomizing agent can be selected from ethers, amines, thioethers, potassium or sodium salts of alkylphenylsulfonic acid, alkoxides of potassium or sodium, and the like.

  The rubber content in the transparent rubber-modified polystyrene resin of the present invention is 1 to 40% by weight. However, if the content is less than 1% by weight, the environmental stress crack resistance of the resin is deteriorated, while 40% by weight is reduced. If it exceeds, the transparency of the resin will deteriorate.

  On the other hand, in the copolymer continuous phase (B) used in the present invention, (i-1) the styrene monomer is 20 to 70 parts by weight, preferably 25 to 60 parts by weight, more preferably 30 to 50 parts by weight. Parts, (i-2) (meth) acrylic acid ester monomer is 30 to 80 parts by weight, preferably 40 to 75 parts by weight, more preferably 50 to 70 parts by weight, and (i-3) other 0 to 40 parts by weight of copolymerizable monomer, preferably 1 to 30 parts by weight, more preferably 2 to 20 parts by weight (these (i-1), (i-2) and (i-3) And a total of 100 parts by weight of (i-1), (i-2) and (i-3), and 0.0005 to 1.0 part by weight of a polyfunctional maleimide monomer. Obtained by copolymerization. Here, specific examples of (i-1) styrenic monomers are the same as the styrenic monomers used in the above-mentioned rubbery copolymer, and are omitted here.

  Examples of the (i-2) (meth) acrylic acid ester monomer include methacrylic acid esters and acrylic acid esters. Examples of methacrylic acid esters include methyl methacrylate, ethyl methacrylate, butyl methacrylate, phenyl methacrylate, cyclohexyl methacrylate, 2-hydroxyl methacrylate, glycidyl methacrylate, and the like, while acrylates include methyl acrylate, Examples include ethyl acrylate, n-butyl acrylate, 2-methylpentyl acrylate, 2-ethylpentyl acrylate, octyl acrylate, and the like. Of these, methyl methacrylate and n-butyl acrylate are preferred.

  In the copolymer continuous phase (B) used in the present invention, the other copolymerizable monomer (i-3) is 0 to 40 parts by weight, and the type thereof is not particularly limited. If necessary, the refractive index of the copolymer continuous phase (B) is adjusted by adjusting the ratio of each comonomer to make the resin transparent. Such (i-3) other copolymerizable monomers include unsaturated fatty acids such as itaconic acid, maleic acid, fumaric acid, butenoic acid, cinnamic acid, acrylic acid, methacrylic acid; acrylonitrile, α-methylacrylonitrile Cyanide vinyl monomers such as monofunctional maleimide monomers, unsaturated carboxylic anhydrides such as maleic anhydride, itaconic anhydride, citraconic anhydride, etc., but acrylonitrile is particularly rigid (tensile) This is particularly preferable in terms of high strength.

  The monofunctional maleimide monomer that can be used as the other copolymerizable monomer (i-3) is a monomer containing one maleimide functional group. Specific examples include maleimide, N -Methylmaleimide, N-isopropylmaleimide, N-butylmaleimide, N-hexylmaleimide, N-octylmaleimide, N-dodecylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide, N-2,3-dimethylphenylmaleimide, N -2,4-dimethylphenylmaleimide, N-2,3-diethylphenylmaleimide, N-2,4-diethylphenylmaleimide, N-2,3-dibutylphenylmaleimide, N-2,4-dibutylphenylmaleimide, N -2,6-dimethylphenylmaleimide, N-2,3-dichlorophenylmaleimide, N-2,4-dichlorophenylmaleimide, N-2,3-dibromophenylmaleimide, N-2,4-dibromophenylmale Although bromide and the like, N- phenylmaleimide is particularly preferred.

  The polyfunctional maleimide monomer constituting the copolymer continuous phase (B) used in the present invention refers to a compound having at least two maleimide functional groups, for example, 2, 3 or 4 It is a compound having a maleimide functional group. Among these, bismaleimide monomers (monomers having two maleimide groups) are preferable, and examples of the structural formula are shown in the following chemical formulas (1) and (2).

In the above formulas (1) and (2), X represents an alkylene group having 1 to 10 carbon atoms, an arylene group, an oxycarbonyl group, a carbonyl group, —SO ₂ —, —SO—, —O—, —O—R—. O- (R is an alkylene group or arylene group having 2 to 10 carbon atoms). Moreover, in Chemical formula (2), Y and Y 'are the C1-C4 alkyl groups or aryl groups which may mutually be same or different. Specific examples of the bismaleimide monomer represented by the chemical formulas (1) and (2) include N, N′-4,4 ′-(3,3′-dimethyldiphenylmethane) bismaleimide, N, N ′. -4,4 '-(3,3'-diethyldiphenylmethane) bismaleimide, N, N'-4,4'-diphenylmethane bismaleimide, N, N'-4,4'-(2,2-diphenylpropane) Bismaleimide, N, N′-4,4′-diphenyl ether bismaleimide, N, N′-3,3′-diphenylsulfone bismaleimide, N, N′-4,4′-diphenylsulfone bismaleimide, N, N Examples include '-4,4'-diphenylsulfoxide bismaleimide, N, N'-4,4'-benzophenone bismaleimide, and the like.

  Among the bismaleimide monomers, N, N'-4,4'-diphenylmethane bismaleimide, bis (4-maleimidophenyloxyphenyl) 2,2-propane, N, N'-1,3-phenylenebis Maleimide is preferred.

  In the present invention, the amount of the polyfunctional maleimide monomer used for the copolymer continuous phase (B) is (i-1) styrene monomer, (i-2) (meth) acrylic acid. 0.0005 to 1.0 parts by weight, preferably 0.001 to 0.3 parts by weight, more preferably 0.003 parts by weight, based on 100 parts by weight of the total amount of ester monomers and (i-3) other copolymerizable monomers As mentioned above, it is less than 0.1 weight part. When the amount of the polyfunctional maleimide monomer used exceeds 1.0 part by weight, crosslinking occurs during the polymerization and the viscosity of the polymer increases, and as a result, the progress of the reaction becomes difficult. On the other hand, when the amount of the polyfunctional maleimide monomer used is less than 0.0005 parts by weight, the environmental stress crack resistance of the resin is deteriorated. The amount of the polyfunctional maleimide monomer remaining in the transparent rubber-modified styrene resin is preferably 80 ppm or less, more preferably 40 ppm or less, still more preferably 20 ppm or less, and particularly preferably 0 ppm (that is, transparent rubber-modified styrene). When the polyfunctional maleimide monomer remaining in the resin is not detected). If the amount of the polyfunctional maleimide monomer remaining in the transparent rubber-modified styrene resin exceeds 80 ppm, the transparency of the resin deteriorates and the environmental stress crack resistance cannot be sufficiently improved.

The amount of the polyfunctional maleimide monomer remaining in the transparent rubber-modified polystyrene resin of the present invention can be adjusted by one or several methods described below.
1) It adjusts by the reaction temperature of polymerization, residence time, and the final conversion rate of a monomer (The conversion rate of a preferable monomer is 70% or more).
2) Adjust by combination of polymerization reactor type and quantity. Preferably, the last reactor can use a plug flow (hereinafter referred to as PFR) equation.
3) As a time for adding the polyfunctional maleimide monomer at the time of polymerization, for example, the polyfunctional maleimide monomer is added to the first and second reactors, respectively. Preferably, it is added to the reactor before the last reactor.
4) Adjust the temperature according to the devolatization temperature and the devolatization residence time.

  When the transparent rubber-modified polystyrene resin of the present invention is produced by polymerization, a monofunctional and / or polyfunctional polymerization initiator, monofunctional and / or polyfunctional chain transfer agent can be added as necessary. .

  Specific examples of the monofunctional polymerization initiator that can be used in the present invention include benzoyl peroxide, dicumyl peroxide, t-butyl peroxide, t-butyl hydroperoxide, cumyl hydroperoxide, and t-butyl peroxide. Benzoate, bis-2-ethylhexyl peroxydicarbonate, t-butylperoxyisopropyl carbonate (hereinafter abbreviated as BPIC), cyclohexanone peroxide, 2,2'-azo-bisisobutyronitrile, 1,1'- Examples include azobis- (cyclohexane-1-carbonitrile), 2,2′-azo-bis-2-methylbutyronitrile, dimethyl 2,2′-azobis (2-methylpropionate), and the like. Of these, benzoyl peroxide and dicumyl peroxide are preferred.

  Specific examples of the polyfunctional polymerization initiator that can be used in the present invention include 1,1-bis- (t-butylperoxy) cyclohexane (hereinafter abbreviated as TX-22), 1,1-bis- (t -Butylperoxy) -3,3,5-trimethylcyclohexane (hereinafter abbreviated as TX-29A), 2,5-dimethyl-2,5-bis- (2-ethylhexanoylperoxy) hexane, 4- (T-butylperoxycarbonyl) -3-hexyl-6- [7- (t-butylperoxycarbonyl) heptyl] cyclohexane, di-t-butyl-diperoxyazelate, 2,5-dimethyl-2 , 5-bis- (benzoylperoxy) hexane, di-t-butylperoxyhexahydro-terephthalate (hereinafter abbreviated as BPHTP), 2,2-bis- (4,4-di-t-butylperoxy) ) Cyclohexylpropane (hereinafter abbreviated as PX-12), many officials Monoperoxycarbonate (e.g. US ATOFINA trade name Luperox JWE of), and the like. Of these, TX-29A and BPHTP are preferred.

  The amount of the above-mentioned monofunctional polymerization initiator and polyfunctional polymerization initiator used for the reaction is 0 to 2 parts by weight with respect to 100 parts by weight of the monomer used for polymerization, preferably 0.001 to 0.7 parts by weight.

The chain transfer agent that can be used in the present invention includes a monofunctional chain transfer agent and a polyfunctional chain transfer agent. Specific examples of the monofunctional chain transfer agent include the following.
1) Mercaptans: methyl mercaptan, n-butyl mercaptan, cyclohexyl mercaptan, n-dodecyl mercaptan, stearyl mercaptan, t-dodecyl mercaptan (hereinafter abbreviated as TDM), n-propyl mercaptan, n-octyl mercaptan, t-octyl Mercaptans, t-nonyl mercaptans, 5-t-butyl-2-methyl-thiophenol and the like.
2) Alkylamines: monoethylamine, diethylamine, triethylamine, monoisopropylamine, diisopropylamine, monobutylamine, di-n-butylamine, tri-n-butylamine and the like.
3) Others: Examples include pentaphenylethane, α-methylstyrene dimer, terpinolene, and the like. Among these, mercaptans such as n-dodecyl mercaptan and t-dodecyl mercaptan are preferable.

  On the other hand, specific examples of the multifunctional chain transfer agent include pentaerythritol tetrakis (3-mercaptopropionate), pentaerythritol tetrakis (2-mercaptoacetate), trimethylolpropane tris (2-mercaptoacetate), trimethylolpropane. Tris (3-mercaptopropionate) (hereinafter abbreviated as TMPT), trimethylolpropane tris (6-mercaptohexanate), 1,8-dimercaptooctane, and the like can be given. Of these, trimethylolpropane tris (3-mercaptopropionate) is preferred.

  Said chain transfer agent is 0-2 weight part with respect to 100 weight part of monomers used for superposition | polymerization, Preferably it is 0.001-1 weight part.

  In the transparent rubber-modified polystyrene resin of the present invention, the weight average molecular weight of the copolymer continuous phase (B) is generally 50,000 to 300,000, preferably 60,000 to 200,000, more preferably 70. , 150,000 to 150,000.

  In the transparent rubber-modified polystyrene resin of the present invention, the rubber particle dispersed phase (A) preferably has a weight average particle diameter of 0.1 μm to 1.5 μm, more preferably 0.15 μm to 1.3 μm, and still more preferably 0.8. 2 μm to 1.0 μm. When the weight average particle diameter of the rubber particles is 0.1 μm to 1.5 μm, the physical property balance between transparency and impact strength of the resin is good.

  The weight average particle diameter of the rubber particles is adjusted by selecting the type of rubber (for example, viscosity, molecular weight, cis / trans / vinyl structure, etc.), type and stirring speed of the polymerization reactor, reaction temperature, conversion of the polymerization monomer. It can be carried out by one or several methods such as rate, type of solvent and amount used.

  The weight average particle diameter of the rubber particles can be obtained by analyzing from a photograph obtained by an ultrathin section method using a transmission electron microscope. The number of particles present in the obtained photograph is required to be 300 or more, and the weight average particle diameter is calculated by the following formula when analyzing the photograph.

  In the above formula, ni represents the number of rubber particles having a particle diameter Di.

  The transparency of the transparent rubber-modified polystyrene resin of the present invention is determined by the difference in refractive index between the resin continuous copolymer phase (B) and the rubber particle dispersed phase (A). The difference in refractive index between the copolymer continuous phase (B) and the rubber particle dispersed phase (A) is preferably 0.01 or less, more preferably 0.007 or less, and still more preferably 0.005 or less. When the difference is 0.01 or less, the transparency of the resin is good.

  The difference in refractive index between the copolymer continuous phase (B) and the rubber particle dispersed phase (A) is as follows: (i-1) styrene monomer of the copolymer continuous phase (B), (i-2) Combination of (meth) acrylic acid ester monomer and (i-3) other copolymerizable monomer, and monomer composition of rubbery polymer in rubber particle dispersed phase (A) (for example, styrene) And a butadiene type).

  The method for producing the transparent rubber-modified polystyrene resin of the present invention includes (i-1) a styrene monomer, (i-2) a (meth) acrylic acid ester monomer in the presence of a rubbery copolymer. Body, polyfunctional maleimide monomer, and (i-3) other copolymerizable monomer as required, and batch type or continuous type bulk or solution graft polymerization reaction may be performed. it can. Taking a continuous solution graft polymerization reaction as an example, first, 1-40 parts by weight of a rubbery copolymer, and (i-1) 20-70 parts by weight of a styrene monomer (preferably 25-60 parts by weight, More preferably 30-50 parts by weight), (i-2) (meth) acrylic acid ester monomer 30-80 parts by weight (preferably 40-75 parts by weight, more preferably 50-70 parts by weight), and (i-3) Other copolymerizable monomers 0 to 40 parts by weight (preferably 1 to 30 parts by weight, more preferably 2 to 20 parts by weight) (the above (i-1) to (i-3) The total amount of the monomers is 100 parts by weight), and the polyfunctional maleimide monomer is 0.0005 to 1.0 parts by weight (preferably 0.001 to 0.3 parts by weight, more preferably 0.003). ~ 0.15 parts by weight) and, if necessary, a suitable solvent is used to form a raw material mixed solution. Said raw material mixed solution melt | dissolves in the dissolution tank which has a well-known high shear force and a high stirring speed. As such a dissolution tank, a tape-shaped spiral stirring blade, a spiral stirring blade or other stirring blade that generates a high shearing force is provided, and the rubber-like copolymer is completely dissolved over a sufficient amount of time to obtain a rubber solution. And then pumped to the reactor. The raw material solution or the monomer solution is separately and continuously fed to the first reactor and / or the second reactor, and / or further to the next reactor. At the same time, if necessary, additional styrene monomer, (meth) acrylate monomer, other copolymerizable monomer, multifunctional to the first and / or second and / or further reactor A graft polymerization reaction is carried out by adding a functional maleimide monomer, a chain transfer agent, a polymerization initiator and the like.

  Examples of the reactor include a continuous stirring reactor (hereinafter referred to as CSTR), a plug flow reactor (PFR), a static mixed reactor, etc., and the same or different reactors are used in combination. can do. Although the reaction temperature can be controlled between 70-230 ° C. and the conversion rate of the final monomer can be 30-95%, 50-90% is more preferable, and 65-90% is most preferable.

  In the polymerization method of the transparent rubber-modified polystyrene resin of the present invention, a reactor (CSTR) in which the first reactor is preferably a continuous stirring type is preferably used. The second and / or subsequent reactor can be taken over, and the subsequent reactor may be a continuous stirring reactor, a plug flow reactor, a static mixing reactor, or the like.

  In general, the monomer conversion in the first reactor is preferably about 1 to 40% by weight, more preferably 2 to 35% by weight, and still more preferably 3 to 30% by weight. The monomer conversion rate in the first reactor can be adjusted by the content, type, viscosity, etc. of the rubbery copolymer used.

  The solvent used when polymerizing the transparent rubber-modified polystyrene resin of the present invention is preferably toluene, ethylbenzene, dimethylbenzene, butanone for ketones, and ethyl acetate for esters, for aromatic hydrocarbon compounds. In addition, in the present invention, aliphatic hydrocarbon compounds such as n-hexane, cyclohexane, and n-heptane can be used as a part of the solvent.

  After the above polymerization reaction is completed, the reaction product is removed from the reactor, and the polymer is recovered by removing low-volatile components such as unreacted monomers and solvents with a devolatilization apparatus, whereby the transparent rubber of the present invention is recovered. A modified polystyrene resin is obtained.

  Examples of the devolatilization device include a devolatilization tank and / or a single-screw and / or twin-screw extruder. If necessary, a devolatilization aid such as water, cyclohexane, carbon dioxide, etc. may be added to the extruder, and the amount of the aid used is generally 10% by weight or less (feed amount to the extruder is 100 weights). %). The extruder is provided with a kneading zone, a propulsion zone, etc. as necessary, and the rotational speed of the screw is 120 to 350 rpm. In the present invention, a twin screw extruder with a discharge port is preferable. A devolatilizing tank with vacuum means can also be used. One or several of the above devolatilization tanks can be used in series, and the temperature is controlled at 180 to 350 ° C., but preferably 200 to 320 ° C. in order to obtain good practical transparency and hue. Most preferably, the temperature is controlled at 220 to 300 ° C. The degree of vacuum of the tank is controlled to 300 Torr or less, preferably 200 Torr or less, more preferably 100 Torr or less. For example, a thin film evaporator can be used as the other devolatilization means.

  In the transparent rubber-modified polystyrene resin of the present invention, other components can be blended within a range that does not significantly affect the performance of the resin of the present invention. Examples of such other components include colorants, fillers, flame retardants, flame retardant aids (such as antimony trioxide), light stabilizers, heat stabilizers, plasticizers, lubricants, mold release agents, viscosity increasing agents, static Examples thereof include additives such as antistatic agents, antioxidants, and conductive agents. Specific examples include mineral oil, ester plasticizers of butyl stearylate, polyester plasticizers, organic polysiloxanes such as polydimethylsiloxane, higher fatty acids and metal salts thereof, sterically hindered amine antioxidants, glass fibers, and the like. . These additives can be used alone or in combination, and can be added and mixed at the stage of the polymerization reaction or after completion of the reaction.

  The amount of the ester plasticizer or mineral oil used (the amount used relative to 100 parts by weight of the transparent rubber-modified polystyrene resin) is generally 0 to 5 parts by weight, preferably 0.05 to 2 parts by weight. On the other hand, the amount of the organic polysiloxane used (the amount used relative to 100 parts by weight of the transparent rubber-modified polystyrene resin) is 0 to 0.5 parts by weight, preferably 0.002 to 0.2 parts by weight.

  In addition, other resins can be added to the resin of the present invention within a range that does not significantly affect its transparency. Examples of the resin that can be added and formulated include styrene- (meth) acrylate-acrylonitrile copolymer, styrene- (meth) acrylate copolymer, styrene- (meth) acrylate-acrylonitrile-maleimide Copolymers, styrene- (meth) acrylate-maleimide copolymers, (meth) acrylate-maleimide copolymers, or diene rubber-modified copolymers such as styrene-diene- (Meth) acrylate-acrylonitrile copolymer, styrene-diene- (meth) acrylate copolymer, styrene-diene- (meth) acrylate-acrylonitrile-maleimide copolymer, Styrene-diene- (meth) acrylate-maleimide copolymer, (meth) acrylic Rate-based - diene - like maleimide copolymer.

  The amount of the other resin that can be added is 0 to 200 parts by weight with respect to 100 parts by weight of the transparent rubber-modified polystyrene resin, and the added amount adjusts the heat resistance, rigidity, and fluid processability of the resin. Or it can be increased.

  The use of the transparent rubber-modified polystyrene resin of the present invention is not particularly limited, but various molded products such as injection molding, compression molding, extrusion molding, blow molding, thermoforming (vacuum molding, etc.), molded products by hollow molding, and thin film molded products. It can be designed to meet the requirements of high fluidity and high heat resistance depending on the formulation.

  Addition and mixing of the above-mentioned other components or resin is generally 160 ° C. to 280 ° C., preferably 180 ° C. to 250 ° C., using a general melt kneader such as a Banbury mixer, roll kneader, single screw or twin screw extruder. Kneading at a temperature of ° C. There is no restriction | limiting in particular in the addition order of each compounding component.

Physical property measurement

In the following examples, each physical property was measured by the following method.
1. Transparency measurement method (haze, unit:%):
The resin is molded into a 3 mm thick test piece and its transparency is measured according to ASTM D-1003 standard. The higher the Haze value obtained, the worse the transparency. In Tables 1 to 4, “transparency” is indicated.
2. Impact resistance:
Measurement is performed according to ASTM D-256 method (1/4 inch thick sheet with notch, unit: kg-cm / cm). In Tables 1 to 4, “impact resistance strength” is shown.
3. Environmental stress crack resistance test method for resin:
A test piece of 100 mm × 12.7 mm × 3 mm is mounted on a jig having a radius of 165 mm and immersed in salad oil. Measure the time to crack the specimen after soaking. The longer the generation time, the better the environmental stress crack resistance of the resin. In Tables 1 to 4, “environmental stress crack resistance” is shown.
○: 48 hours or more.
Δ: 24 hours or more and less than 48 hours.
X: Less than 24 hours.
4). Difference in refractive index between the resin continuous copolymer phase (B) and the rubber particle dispersed phase (A):
10 g of the resin is weighed and dissolved in 300 ml of acetone for 24 hours, and then the soluble component and the insoluble component are separated with a centrifuge (12000 rpm × 30 min). The separated soluble component is further heated and concentrated, and then methanol is added to precipitate a polymer. And after drying the obtained soluble part and insoluble part in a vacuum thermostat (80 degreeC x 4 hours), each is made into a thin film and each refractive index is measured with an Abbe refractometer. The difference between the refractive index of the obtained soluble component and the refractive index of the insoluble component is the difference between the refractive index of the continuous copolymer phase (B) and the refractive index of the dispersed phase (A). In Tables 1 to 4, “difference in refractive index between (A) and (B)” is shown.

  14.0 parts by weight of a rubbery copolymer (PR-1205 manufactured by Kitami Co., Ltd., styrene / butadiene content = 25/75, 1,2-vinyl group content = 15.4 wt%, solution viscosity is 10, taper The weight average molecular weight of the block copolymer is 130,000), and 38 parts by weight of styrene, 62 parts by weight of methyl methacrylate, 46 parts by weight of ethylbenzene, 0.03 part by weight of N, N′-4,4′-diphenylmethane bismaleimide, A raw material solution consisting of 0.11 part by weight of dodecyl mercaptan and 0.13 part by weight of benzoyl peroxide is prepared and continuously sent to a first reactor of a continuous polymerization apparatus at a flow rate of 35 kg / hr by a pump to cause a polymerization reaction. The finished polymer solution was sent to the second reactor. On the other hand, a raw material solution consisting of 100 parts by weight of styrene and 0.01 parts by weight of N, N′-4,4′-diphenylmethane bismaleimide is continuously sent to the second reactor by a pump at a flow rate of 1 kg / hr to cause the reaction. It was. The polymer solution which finished the reaction in the second reactor was sent to the third reactor. The polymer solution that had been reacted in the third reactor was further sent to the fourth reactor for polymerization.

  Said 1st, 2nd, 3rd, 4th reactor is a continuous apparatus connected in this order, and the capacity | capacitance of a 1st, 2nd, and 3rd reactor becomes a 40 liter each, and is a continuous stirring type reactor (CSTR), the fourth reactor is a 75 liter plug flow reactor (PFR). The first reactor has a temperature of 95 ° C. and a stirring speed of 300 rpm, the second reactor has a temperature of 105 ° C. and a stirring speed of 200 rpm, the third reactor has a temperature of 115 ° C. and a stirring speed of 150 rpm, and the fourth reactor. The temperature was 135 ° C. and the stirring speed was 35 rpm. The final polymerization conversion was 75%. After completion of the reaction, unreacted monomer and solvent were removed with a devolatilizer, and then extruded with an extruder, cooled and pelletized to obtain the transparent rubber-modified styrene resin of the present invention.

As a result of the analysis, the rubber content was 15.2% by weight, the rubber particle weight average particle size was 0.39 μm, and the difference in refractive index between the copolymer continuous phase (B) and the rubber particle dispersed phase (A) was 0.00. 002, the remaining N, N′-4,4′-diphenylmethane bismaleimide was 4 ppm. The measured physical properties are shown in Table 1. Moreover, the tensile strength calculated | required by ASTM D-368 about this resin was 405 kg / cm < ² >.

  The composition of the raw material solution used in this example is shown in Table 1. The polymer solution was sent continuously to the first reactor of the continuous polymerization apparatus at a flow rate of 35 kg / hr with a pump, and the polymer solution after the reaction was sent to the second reactor. On the other hand, a raw material solution consisting of 100 parts by weight of styrene was continuously sent to the second reactor at a flow rate of 2 kg / hr by a pump to cause a reaction. The number, type and arrangement of the reactors are the same as those in Example 1, and the reactor temperatures and stirring speeds are shown in Table 1, respectively. The final polymerization conversion was 74%. After completion of the reaction, the same treatment as in Example 1 was performed to obtain a transparent rubber-modified styrene resin of the present invention.

  As a result of the analysis, the rubber content was 20.6% by weight, the rubber particle weight average particle diameter was 0.43 μm, and the refractive index difference between the copolymer continuous phase (B) and the rubber particle dispersed phase (A) was 0.00. 002, the remaining N, N′-4,4′-diphenylmethane bismaleimide was less than 1 ppm. The measured physical properties are shown in Table 1.

  The composition of the raw material solution used in this example is shown in Table 1. The polymer solution was sent continuously to the first reactor of the continuous polymerization apparatus at a flow rate of 35 kg / hr with a pump, and the polymer solution after the reaction was sent to the second reactor. On the other hand, a raw material solution consisting of 100 parts by weight of styrene was continuously sent to the second reactor at a flow rate of 2 kg / hr by a pump to cause a reaction. The number, type and arrangement of the reactors are the same as in Example 1, and the temperature and stirring speed of each reactor are shown in Table 1, respectively. The final polymerization conversion was 75%. After completion of the reaction, post-treatment was performed in the same manner as in Example 1 to obtain a transparent rubber-modified styrene resin of the present invention.

  As a result of the analysis, the rubber content was 15.2% by weight, the rubber particle weight average particle diameter was 0.37 μm, and the refractive index difference between the copolymer continuous phase (B) and the rubber particle dispersed phase (A) was 0.00. 002, residual N, N′-4,4′-diphenylmethane bismaleimide was 18 ppm. The measured physical properties are shown in Table 1.

  The composition of the raw material solution used in this example is shown in Table 1. The polymer solution was sent continuously to the first reactor of the continuous polymerization apparatus at a flow rate of 35 kg / hr with a pump, and the polymer solution after the reaction was sent to the second reactor. On the other hand, a raw material solution consisting of 100 parts by weight of styrene and 0.01 parts by weight of N, N′-4,4′-diphenylmethane bismaleimide is continuously sent to the second reactor at a flow rate of 1 kg / hr by a pump to cause reaction. After the reaction in the second reactor was completed, the polymer solution was further sent to the third reactor. Moreover, the raw material solution which consists of 100 weight part of styrene was sent to the 3rd reactor continuously with the flow volume of 1 kg / hr with the pump. The number, type and arrangement of the reactors are the same as those in Example 1, and the reactor temperatures and stirring speeds are shown in Table 1, respectively. The final polymerization conversion was 76%. After completion of the reaction, post-treatment was performed in the same manner as in Example 1 to obtain a transparent rubber-modified styrene resin of the present invention.

  As a result of the analysis, the rubber content was 15.2% by weight, the rubber particle weight average particle diameter was 0.42 μm, and the difference in refractive index between the copolymer continuous phase (B) and the rubber particle dispersed phase (A) was 0.00. 004, the remaining N, N′-4,4′-diphenylmethane bismaleimide was 6 ppm. The measured physical properties are shown in Table 1.

  The composition of the raw material solution used in this example is shown in Table 1. The polymer solution was sent continuously to the first reactor of the continuous polymerization apparatus at a flow rate of 35 kg / hr with a pump, and the polymer solution after the reaction was sent to the second reactor. On the other hand, a raw material solution consisting of 100 parts by weight of styrene and 0.01 parts by weight of N, N′-4,4′-diphenylmethane bismaleimide is continuously sent to the second reactor at a flow rate of 1 kg / hr by a pump to cause reaction. After the reaction in the second reactor was completed, the polymer solution was further sent to the third reactor. A raw material solution consisting of 100 parts by weight of styrene was continuously sent to the third reactor by a pump at a flow rate of 1 kg / hr. The number, type and arrangement of the reactors are the same as in Example 1, and the temperature and stirring speed of each reactor are shown in Table 1, respectively. The final polymerization conversion was 77%. After completion of the reaction, post-treatment was performed in the same manner as in Example 1 to obtain a transparent rubber-modified styrene resin of the present invention.

  As a result of the analysis, the rubber content was 15.2% by weight, the rubber particle weight average particle size was 0.4 μm, and the difference in refractive index between the copolymer continuous phase (B) and the rubber particle dispersed phase (A) was 0.00. 002, the remaining N, N′-4,4′-diphenylmethane bismaleimide was 5 ppm. The measured physical properties are shown in Table 1.

  The composition of the raw material solution used in this example is shown in Table 1. The polymer solution was sent continuously to the first reactor of the continuous polymerization apparatus at a flow rate of 35 kg / hr with a pump, and the polymer solution after the reaction was sent to the second reactor. On the other hand, a raw material solution consisting of 100 parts by weight of styrene and 0.002 parts by weight of N, N′-4,4′-diphenylmethane bismaleimide is continuously sent to the second reactor by a pump at a flow rate of 2 kg / hr to cause a reaction. It was. The number, type and arrangement of the reactors are the same as in Example 1, and the temperature and stirring speed of each reactor are shown in Table 1, respectively. The final polymerization conversion was 73%. After completion of the reaction, post-treatment was performed in the same manner as in Example 1 to obtain a transparent rubber-modified styrene resin of the present invention.

  As a result of the analysis, the rubber content was 15.2% by weight, the rubber particle weight average particle size was 0.39 μm, and the difference in refractive index between the copolymer continuous phase (B) and the rubber particle dispersed phase (A) was 0.00. 003, remaining N, N′-4,4′-diphenylmethane bismaleimide was less than 1 ppm. The measured physical properties are shown in Table 1.

  Table 2 shows the composition of the raw material solution used in this example. The polymer solution was sent continuously to the first reactor of the continuous polymerization apparatus at a flow rate of 35 kg / hr with a pump, and the polymer solution after the reaction was sent to the second reactor. On the other hand, a raw material solution consisting of 100 parts by weight of styrene, 0.01 parts by weight of N, N′-4,4′-diphenylmethane bismaleimide and 0.05 parts by weight of TX-29A was continuously pumped at a flow rate of 1 kg / hr. The reaction was sent to the two reactors, and after the reaction in the second reactor was completed, the polymer solution was further sent to the third reactor. Moreover, the raw material solution which consists of 100 weight part of styrene was sent to the 3rd reactor continuously with the flow volume of 1 kg / hr with the pump. The number, type and arrangement of the reactors are the same as in Example 1, and the temperature and stirring speed of each reactor are shown in Table 2, respectively. The final polymerization conversion was 75%. After completion of the reaction, post-treatment was performed in the same manner as in Example 1 to obtain a transparent rubber-modified styrene resin of the present invention.

  As a result of the analysis, the rubber content was 15.2% by weight, the rubber particle weight average particle size was 0.39 μm, and the difference in refractive index between the copolymer continuous phase (B) and the rubber particle dispersed phase (A) was 0.00. 003, the remaining N, N′-4,4′-diphenylmethane bismaleimide was 4 ppm. The measured physical properties are shown in Table 2.

  Table 2 shows the composition of the raw material solution used in this example. The polymer solution was sent continuously to the first reactor of the continuous polymerization apparatus at a flow rate of 35 kg / hr with a pump, and the polymer solution after the reaction was sent to the second reactor. On the other hand, 100 parts by weight of styrene is continuously sent to the second reactor by a pump at a flow rate of 2 kg / hr to cause the reaction, and after the reaction in the second reactor is completed, the polymer solution is further sent to the third reactor. After the reaction in the third reactor, the polymer solution was further sent to the fourth reactor. The four reactors were connected in series in this order, and the four reactors were both continuously stirred reactors (CSTR) with a capacity of 40 liters. Table 2 shows the temperature and stirring speed of each reactor. The final polymerization conversion was 75%. After completion of the reaction, post-treatment was performed in the same manner as in Example 1 to obtain a transparent rubber-modified styrene resin of the present invention.

  As a result of the analysis, the rubber content was 15.2% by weight, the rubber particle weight average particle size was 0.4 μm, and the difference in refractive index between the copolymer continuous phase (B) and the rubber particle dispersed phase (A) was 0.00. 004, the remaining N, N′-4,4′-diphenylmethane bismaleimide was 3 ppm. The measured physical properties are shown in Table 2.

  Table 2 shows the composition of the raw material solution used in this example. The polymer solution was sent continuously to the first reactor of the continuous polymerization apparatus at a flow rate of 35 kg / hr with a pump, and the polymer solution after the reaction was sent to the second reactor. On the other hand, a raw material solution consisting of 100 parts by weight of styrene was continuously sent to the second reactor at a flow rate of 2 kg / hr by a pump to cause a reaction. The number, type and arrangement of the reactors are the same as in Example 1, and the temperature and stirring speed of each reactor are shown in Table 2, respectively. The final polymerization conversion was 74%. After completion of the reaction, post-treatment was performed in the same manner as in Example 1 to obtain a transparent rubber-modified styrene resin of the present invention.

  As a result of the analysis, the rubber content was 15.2% by weight, the rubber particle weight average particle size was 0.44 μm, and the difference in refractive index between the copolymer continuous phase (B) and the rubber particle dispersed phase (A) was 0.00. 002, the remaining N, N′-4,4′-diphenylmethane bismaleimide was 8 ppm. The measured physical properties are shown in Table 2.

  Table 2 shows the composition of the raw material solution used in this example. The polymer solution was sent continuously to the first reactor of the continuous polymerization apparatus at a flow rate of 35 kg / hr with a pump, and the polymer solution after the reaction was sent to the second reactor. On the other hand, a raw material solution consisting of 100 parts by weight of styrene was continuously sent to the second reactor at a flow rate of 2 kg / hr by a pump to cause a reaction. The number, type and arrangement of the reactors are the same as those in Example 1, and the reactor temperatures and stirring speeds are shown in Table 2, respectively. The final polymerization conversion was 76%. After completion of the reaction, post-treatment was performed in the same manner as in Example 1 to obtain a transparent rubber-modified styrene resin of the present invention.

  As a result of the analysis, the rubber content was 15.2% by weight, the rubber particle weight average particle size was 0.4 μm, and the difference in refractive index between the copolymer continuous phase (B) and the rubber particle dispersed phase (A) was 0.00. 006, the remaining N, N′-4,4′-diphenylmethane bismaleimide was 6 ppm. The measured physical properties are shown in Table 2.

  The raw material solution composition used in this example is shown in Table 2. The polymer solution was sent continuously to the first reactor of the continuous polymerization apparatus at a flow rate of 35 kg / hr with a pump, and the polymer solution after the reaction was sent to the second reactor. On the other hand, a raw material solution consisting of 100 parts by weight of styrene was continuously sent to the second reactor at a flow rate of 2 kg / hr by a pump to cause a reaction. The number, type and arrangement of the reactors are the same as in Example 1, and the temperature and stirring speed of each reactor are shown in Table 2, respectively. The final polymerization conversion was 78%. After completion of the reaction, post-treatment was performed in the same manner as in Example 1 to obtain a transparent rubber-modified styrene resin of the present invention.

As a result of the analysis, the rubber content was 15.2% by weight, the rubber particle weight average particle diameter was 0.42 μm, and the difference in refractive index between the copolymer continuous phase (B) and the rubber particle dispersed phase (A) was 0.00. 005, the remaining N, N′-4,4′-diphenylmethane bismaleimide was 14 ppm. The measured physical properties are shown in Table 2. Moreover, the tensile strength calculated | required by ASTM D-368 about this resin was 440 kg / cm < ² >.

  14.0 parts by weight of a rubbery copolymer (PR-1205 manufactured by Kitami Co., Ltd., styrene / butadiene content = 25/75, 1,2-vinyl group content = 15.4 wt%, solution viscosity is 10, taper The weight average molecular weight of the block copolymer is 130,000), 38 parts by weight of styrene, 62 parts by weight of methyl methacrylate, 46 parts by weight of ethylbenzene, N, N′-4,4 ′-(2,2-diphenylpropane) bis A raw material solution consisting of 0.03 part by weight of maleimide, 0.11 part by weight of dodecyl mercaptan and 0.13 part by weight of benzoyl peroxide is prepared and continuously fed to the first reactor of the continuous polymerization apparatus at a flow rate of 35 kg / hr by a pump. The polymerization reaction was carried out, and the polymer solution after the reaction was sent to the second reactor. On the other hand, a raw material solution comprising 100 parts by weight of styrene and 0.01 parts by weight of N, N′-4,4 ′-(2,2-diphenylpropane) bismaleimide is continuously pumped at a flow rate of 1 kg / hr. The reaction was sent to the reactor. The polymer solution which finished the reaction in the second reactor was sent to the third reactor. The polymer solution that had been reacted in the third reactor was further sent to the fourth reactor for polymerization.

  Said 1st, 2nd, 3rd, 4th reactor is a continuous apparatus connected in this order, and the capacity | capacitance of a 1st, 2nd, and 3rd reactor becomes a 40 liter each, and is a continuous stirring type reactor (CSTR), the fourth reactor is a 75 liter plug flow reactor (PFR). The first reactor has a temperature of 95 ° C. and a stirring speed of 300 rpm, the second reactor has a temperature of 105 ° C. and a stirring speed of 200 rpm, the third reactor has a temperature of 115 ° C. and a stirring speed of 150 rpm, and the fourth reactor. The temperature was 135 ° C. and the stirring speed was 35 rpm. The final polymerization conversion was 75%. After completion of the reaction, unreacted monomer and solvent were removed with a devolatilizer, and then extruded with an extruder, cooled and pelletized to obtain the transparent rubber-modified styrene resin of the present invention.

  As a result of the analysis, the rubber content was 15.2% by weight, the rubber particle weight average particle size was 0.39 μm, and the difference in refractive index between the copolymer continuous phase (B) and the rubber particle dispersed phase (A) was 0.00. 002, the remaining N, N′-4,4 ′-(2,2-diphenylpropane) bismaleimide was 8 ppm. As for the measured physical properties, the haze value was 3.92%, the environmental stress crack resistance was evaluated as ◯, and the impact strength was 13.8 kg-cm / cm.

  14.0 parts by weight of a rubbery copolymer (PR-1205 manufactured by Kitami Co., Ltd., styrene / butadiene content = 25/75, 1,2-vinyl group content = 15.4 wt%, solution viscosity is 10, taper The weight average molecular weight of the block copolymer is 130,000), and 38 parts by weight of styrene, 62 parts by weight of methyl methacrylate, 46 parts by weight of ethylbenzene, 0.03 part by weight of N, N′-4,4′-diphenyl ether bismaleimide, A raw material solution consisting of 0.11 part by weight of dodecyl mercaptan and 0.13 part by weight of benzoyl peroxide is prepared and continuously sent to a first reactor of a continuous polymerization apparatus at a flow rate of 35 kg / hr by a pump to cause a polymerization reaction. The finished polymer solution was sent to the second reactor. On the other hand, a raw material solution consisting of 100 parts by weight of styrene and 0.01 parts by weight of N, N′-4,4′-diphenyl ether bismaleimide is continuously sent to the second reactor with a pump at a flow rate of 1 kg / hr to cause a reaction. It was. The polymer solution which finished the reaction in the second reactor was sent to the third reactor. The polymer solution that had been reacted in the third reactor was further sent to the fourth reactor for polymerization.

  Said 1st, 2nd, 3rd, 4th reactor is a continuous apparatus connected in this order, and the capacity | capacitance of a 1st, 2nd, and 3rd reactor becomes a 40 liter each, and is a continuous stirring type reactor (CSTR), the fourth reactor is a 75 liter plug flow reactor (PFR). The first reactor has a temperature of 95 ° C. and a stirring speed of 300 rpm, the second reactor has a temperature of 105 ° C. and a stirring speed of 200 rpm, the third reactor has a temperature of 115 ° C. and a stirring speed of 150 rpm, and the fourth reactor. The temperature was 135 ° C. and the stirring speed was 35 rpm. The final polymerization conversion was 75%. After completion of the reaction, unreacted monomer and solvent were removed with a devolatilizer, and then extruded with an extruder, cooled and pelletized to obtain the transparent rubber-modified styrene resin of the present invention.

  As a result of the analysis, the rubber content was 15.2% by weight, the rubber particle weight average particle diameter was 0.38 μm, and the difference in refractive index between the copolymer continuous phase (B) and the rubber particle dispersed phase (A) was 0.00. 002, the remaining N, N′-4,4′-diphenyl ether bismaleimide was 7 ppm. As for the measured physical properties, the haze value was 4.11%, the environmental stress crack resistance was evaluated as ◯, and the impact strength was 13.4 kg-cm / cm.

Comparative Example 1

  14.0 parts by weight of a rubber-like polymer (PR-1205 manufactured by Kitami Co., Ltd., styrene / butadiene content = 25/75, 1,2-vinyl group content = 15.4 wt%, solution viscosity is 10, taper block A raw material solution comprising a copolymer having a weight average molecular weight of 130,000), styrene 24 parts by weight, methyl methacrylate 76 parts by weight, ethylbenzene 46 parts by weight, dodecyl mercaptan 0.11 parts by weight, and benzoyl peroxide 0.13 parts by weight. Made and continuously sent to the first reactor of the continuous polymerization apparatus at a flow rate of 37 kg / hr with a pump, the polymer solution after the reaction is sent to the second reactor, and the reaction is completed in the second reactor Thereafter, the polymer solution was further sent to the third reactor, and after completion of the reaction in the third reactor, the polymer solution was further sent to the fourth reactor. Said 1st, 2nd, 3rd, 4th reactor is a continuous apparatus connected in this order, and the capacity | capacitance of a 1st, 2nd, and 3rd reactor becomes a 40 liter each, and is a continuous stirring type reactor (CSTR), the fourth reactor is a 75 liter plug flow reactor. The first reactor has a temperature of 95 ° C. and a stirring speed of 300 rpm, the second reactor has a temperature of 105 ° C. and a stirring speed of 200 rpm, the third reactor has a temperature of 115 ° C. and a stirring speed of 150 rpm, and the fourth reactor. The temperature was 135 ° C. and the stirring speed was 90 rpm. The final polymerization conversion was 75%. After completion of the reaction, the unreacted monomer and solvent were removed with a devolatilizer, and then extruded with an extruder, cooled and pelletized to obtain a transparent rubber-modified styrene resin of this comparative example.

  As a result of the analysis, the rubber content was 15.2% by weight, the rubber particle weight average particle size was 0.4 μm, and the difference in refractive index between the copolymer continuous phase (B) and the rubber particle dispersed phase (A) was 0.00. 025, N, N′-4,4′-diphenylmethane bismaleimide remaining was 0 ppm. The measured physical properties are shown in Table 3.

Comparative Example 2

  Table 3 shows the composition of the raw material solution used in this comparative example. The polymerization reaction is continuously sent to the first reactor at a flow rate of 37 kg / hr by a pump, the polymer solution after the reaction is sent to the second reactor, and after the reaction in the second reactor is finished, the polymer solution Was sent to the third reactor. The first, second, and third reactors are continuous devices connected in this order, the first and second reactors are both 40 liters of continuous stirring reactors, and the third reactor is 75 liters in volume. Plug flow reactor. Table 3 shows the temperature and stirring speed of each reactor. The final polymerization conversion was 76%. After completion of the reaction, post-treatment was performed in the same manner as in Example 1.

  The obtained resin was analyzed, and its rubber content was 15.2% by weight, the weight average particle diameter of the rubber particles was 0.68 μm, and the refraction of the copolymer continuous phase (B) and the rubber particle dispersed phase (A). The difference in rate was 0.022, and the remaining N, N′-4,4′-diphenylmethane bismaleimide was 13 ppm. The measured physical properties are shown in Table 3.

Comparative Example 3

  Table 3 shows the composition of the raw material solution used in this comparative example. The polymer solution was sent continuously to the first reactor of the continuous polymerization apparatus at a flow rate of 35 kg / hr with a pump, and the polymer solution after the reaction was sent to the second reactor. On the other hand, 100 parts by weight of styrene was continuously sent to the second reactor by a pump at a flow rate of 2 kg / hr to cause the reaction, and after the reaction in the second reactor was completed, the polymer solution was sent to the third reactor. The first, second, and third reactors are continuous devices connected in this order, the first and second reactors are both 40 liters of continuous stirring reactors, and the third reactor is 75 liters in volume. Plug flow reactor. Table 3 shows the temperature and stirring speed of each reactor. The final polymerization conversion was 74%. After completion of the reaction, post-treatment was performed in the same manner as in Example 1.

  The obtained resin was analyzed, and its rubber content was 15.2% by weight, the weight average particle diameter of the rubber particles was 0.39 μm, and the refraction of the copolymer continuous phase (B) and the rubber particle dispersed phase (A). The difference in rate was 0.004, and the remaining N, N′-4,4′-diphenylmethane bismaleimide was 0 ppm. The measured physical properties are shown in Table 3.

Comparative Example 4

  Table 3 shows the composition of the raw material solution used in this comparative example. The polymerization reaction was continuously sent to the first reactor at a flow rate of 37 kg / hr with a pump, and the polymer solution after the reaction was sent to the second reactor. After the reaction in the second reactor was completed, the polymer solution was sent to the third reactor, and after the reaction in the third reactor was completed, the polymer solution was further sent to the fourth reactor. The first, second, and third reactors are continuous devices connected in this order, the first, second, and third reactors are both continuous stirring reactors with a capacity of 40 liters, and the fourth reactor is It was a plug flow reactor with a capacity of 75 liters. During the reaction, the viscosity of the reaction system increased significantly, causing a crosslinking phenomenon, and the polymer viscosity increased rapidly, exceeding the load capacity of the reactor, and as a result, the polymerization reaction could not proceed.

Comparative Example 5

  Table 3 shows the composition of the raw material solution used in this comparative example. The polymerization reaction was continuously sent to the first reactor at a flow rate of 37 kg / hr with a pump, and the polymer solution after the reaction was sent to the second reactor. After the reaction in the second reactor was completed, the polymer solution was sent to the third reactor. The first, second, and third reactors are continuous devices connected in this order, the first and second reactors are both 40 liters of continuous stirring reactors, and the third reactor is 75 liters in volume. Plug flow reactor. Table 3 shows the temperature and stirring speed of each reactor. The final polymerization conversion was 70%. After completion of the reaction, post-treatment was performed in the same manner as in Example 1.

  The obtained resin was analyzed, and its rubber content was 44.3% by weight, the weight average particle diameter of the rubber particles was 0.54 μm, and the refraction of the copolymer continuous phase (B) and the rubber particle dispersed phase (A). The difference in rate was 0.008, and the remaining N, N′-4,4′-diphenylmethane bismaleimide was 18 ppm. The measured physical properties are shown in Table 3.

Comparative Example 6

  Table 4 shows the composition of the raw material solution used in this comparative example. The polymerization reaction was sent to the first reactor by a pump at a flow rate of 35 kg / hr, and the polymer solution after the reaction was sent to the second reactor. The first and second reactors were continuous devices connected in this order, and the two reactors were both continuously stirred reactors with a capacity of 40 liters. Table 4 shows the temperature and stirring speed of each reactor. The final polymerization conversion was 63%. After completion of the reaction, post-treatment was performed in the same manner as in Example 1.

  The obtained resin was analyzed and its rubber content was 0.3% by weight, the weight average particle diameter of the rubber particles was 0.31 μm, and the refraction of the copolymer continuous phase (B) and the rubber particle dispersed phase (A). The difference in rate was 0.001, and the remaining N, N′-4,4′-diphenylmethane bismaleimide was 40 ppm. The measured physical properties are shown in Table 4.

Comparative Example 7

  Table 4 shows the composition of the raw material solution used in this comparative example. The polymerization reaction was continuously sent to the first reactor at a flow rate of 44 kg / hr by a pump, and the polymer solution after the reaction was sent to the second reactor. On the other hand, a raw material solution consisting of 100 parts by weight of styrene and 0.025 parts by weight of N, N′-4,4′-diphenylmethane bismaleimide is continuously sent to the second reactor with a pump at a flow rate of 1 kg / hr to cause a reaction. After the reaction in the second reactor was completed, the polymer solution was sent to the third reactor. The first, second and third reactors were each a continuous apparatus connected in this order, and the first, second and third reactors were both continuous stirring reactors with a capacity of 40 liters. Table 4 shows the temperature and stirring speed of each reactor. The final polymerization conversion was 64%. After completion of the reaction, post-treatment was performed in the same manner as in Example 1.

  The obtained resin was analyzed, and its rubber content was 13.9% by weight, the rubber particle weight average particle size was 0.4 μm, and the refraction of the copolymer continuous phase (B) and the rubber particle dispersed phase (A). The difference in rate was 0.013, and the remaining N, N′-4,4′-diphenylmethane bismaleimide was 120 ppm. The measured physical properties are shown in Table 4.

Comparative Example 8

  Table 4 shows the composition of the raw material solution used in this comparative example. The polymerization reaction was continuously sent to the first reactor at a flow rate of 35 kg / hr with a pump, and the polymer solution after the reaction was sent to the second reactor. After the reaction in the second reactor was completed, the polymer solution was sent to the third reactor, and after the reaction in the third reactor was completed, the polymer solution was sent to the fourth reactor. The first, second, third, and fourth reactors are each a continuous apparatus connected in this order, and the first, second, third, and fourth reactors are both continuous stirring reactors with a capacity of 40 liters. there were. Table 4 shows the temperature and stirring speed of each reactor. The final polymerization conversion was 75%. After completion of the reaction, post-treatment was performed in the same manner as in Example 1.

  The obtained resin was analyzed, and its rubber content was 15.2% by weight, the weight average particle diameter of the rubber particles was 0.45 μm, and the refraction of the copolymer continuous phase (B) and the rubber particle dispersed phase (A). The difference in rate was 0.04, and the remaining N, N′-4,4′-diphenylmethane bismaleimide was 3 ppm. The measured physical properties are shown in Table 4.

Comparative Example 9

  Table 4 shows the composition of the raw material solution used in this comparative example. The polymerization reaction was continuously sent to the first reactor at a flow rate of 44 kg / hr by a pump, and the polymer solution after the reaction was sent to the second reactor. On the other hand, a raw material solution consisting of 100 parts by weight of styrene and 0.022 parts by weight of N, N′-4,4′-diphenylmethane bismaleimide is continuously sent to the second reactor with a pump at a flow rate of 1 kg / hr to cause a reaction. After the reaction in the second reactor was completed, the polymer solution was sent to the third reactor. The first, second and third reactors were each a continuous apparatus connected in this order, and the first, second and third reactors were both continuous stirring reactors with a capacity of 40 liters. Table 4 shows the temperature and stirring speed of each reactor. The final polymerization conversion was 63%. After completion of the reaction, post-treatment was performed in the same manner as in Example 1.

  The obtained resin was analyzed, and its rubber content was 13.9% by weight, the rubber particle weight average particle size was 0.4 μm, and the refraction of the copolymer continuous phase (B) and the rubber particle dispersed phase (A). The difference in rate was 0.003, and the remaining N, N′-4,4′-diphenylmethane bismaleimide was 105 ppm. The measured physical properties are shown in Table 4.

In addition, the symbol thru | or abbreviation in the said Tables 1-4 are as follows.
PR-1205: manufactured by Kitamisha Co., Ltd., styrene / butadiene content = 25/75, solution viscosity 10 cps, taper block copolymer
LBR: manufactured by Kitamisha, low-cis polybutadiene rubber, 1,2-vinyl group content = 13 wt%, solution viscosity 170cps
CSTR: Continuous stirring reactor
PFR: Plug flow reactor
BPO: Benzoyl peroxide
TX-29A: 1,1-bis-t-butyloxy-3,3,5-trimethylcyclohexane
PX-12: 2,2-bis (4,4-di-t-butyloxy) cyclohexylpropane
BMI: N, N'-4,4'-diphenylmethane bismaleimide
TDM: Dodecyl mercaptan
SM: Styrene
AN: Acrylonitrile
MMA: Methyl methacrylate
n-BA: n-Butyl acrylate The above is a description of some preferred embodiments of the present invention and is not intended to limit the present invention. Any modifications or changes made within the spirit of the invention are claimed to be within the scope of the invention.

Claims (2)

Rubber particles (A) made of a rubbery copolymer are used as a dispersed phase, and (i-1) 20 to 70 parts by weight of a styrene monomer, (i-2) (meth) acrylate monomer 30 to 80 parts by weight and (i-3) 0 to 40 parts by weight of other copolymerizable monomers, and a total of 100 parts by weight of the above (i-1), (i-2) and (i-3) On the other hand, a transparent rubber-modified polystyrene resin having a continuous phase copolymer (B) obtained by copolymerizing 0.0005 to 1.0 part by weight of a polyfunctional maleimide monomer,
Residual polyfunctional maleimide monomer is 80 ppm or less,
A transparent rubber-modified styrene resin in which the difference in refractive index between the copolymer (B) and the rubber particles (A) is 0.01 or less, and the rubber content in the transparent rubber-modified polystyrene resin is 1 to 40% by weight .   The transparent rubber-modified styrene resin according to claim 1, wherein the rubber particles (A) have a weight average particle diameter of 0.1 µm to 1.5 µm.