JP2006321970A - Styrene-based resin composition and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a styrene-based resin composition that has excellent regularity, provides a molding having excellent mechanical properties, fluidity and chemical resistance by finely controlling the structure of the composition and has high practicality as a general molding material. <P>SOLUTION: The styrene-based resin composition comprises (A) a styrene-based resin that has (a1) 20-75 wt.% of a styrene-based monomer unit, (a2) 25-60 wt.% of a vinyl cyanide-based monomer unit and (a3) 0-55 wt.% of another vinyl-based monomer unit copolymerizable with them and (B) a thermoplastic resin except the styrene-based resin and has a two-phase continuous structure with 0.001-1μm structural period or a dispersion structure of 0.001-1μm distances between particles. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a structural material that makes use of excellent mechanical properties and a styrene resin composition that can be usefully used as a functional material making use of excellent regularity. The present invention also relates to a method for producing a styrenic resin composition whose structure can be controlled from nanometer order to micron order.

  Styrenic resins are used in a wide range of fields such as electrical and electronic equipment, automobiles, machine parts, general merchandise, and various other applications due to their excellent mechanical properties, molding processability, and appearance. However, since styrene resin is inferior in impact resistance and heat resistance, a flexible component such as rubber is added to improve impact resistance, and a resin or crystallinity with a high glass transition temperature is used to improve heat resistance. Various techniques such as addition of a resin have been proposed.

  Among them, as a method for improving the toughness and heat resistance of the styrene resin, many methods for forming a polymer alloy with a polycarbonate resin have been reported, but there has been a problem that melt processability and chemical resistance are lowered. Therefore, as a method for solving these problems, a method of increasing the vinyl cyanide content in a composition comprising a polycarbonate resin and an ABS resin is generally known. However, if the amount of vinyl cyanide is increased, chemical resistance is increased. However, since vinyl cyanide has a high polarity, compatibility with the polycarbonate resin is deteriorated, and mechanical properties and molding processability are greatly reduced.

  As a technique for solving this problem, a method of defining a triple sequence amount of acrylonitrile to be cyclized during melt processing (Patent Document 1) or two specific types of ABS resins having different vinyl cyanide amounts are added to a polycarbonate resin. A method (Patent Document 2) and a method of adding an olefin-unsaturated carboxylic acid alkyl ester copolymer as a third component excellent in chemical resistance (Patent Document 3) are disclosed. However, the resin compositions obtained in both cases are not only satisfactory in chemical resistance but also not satisfactory in mechanical properties and molding processability.

In addition, it is a polymer alloy composed of two or more components phase-separated by spinodal decomposition, and has a biphasic continuous structure having a periodic structure of 0.01 to 1 μm or a dispersed structure having a distance between particles of 0.01 to 1 μm. A method (Patent Document 4) is disclosed. However, the polymer alloy described in this publication does not consider the composition of the resin component used. In the composition of the styrene resin and the polycarbonate resin specifically disclosed in Patent Document 4, since the styrene resin having a low vinyl cyanide unit content is used, the compatibility with the polycarbonate resin is good. Although there was no chemical resistance. Further, the polymer alloy described in the publication is obtained by melt-kneading and then obtaining the structure by special press molding. This structure is simply applied to a composition having a relatively high vinyl cyanide unit content, and injection. When molding by a general molding method such as molding, the structural period becomes too large during molding, and excellent physical properties cannot be obtained, and the above phase structure cannot be obtained stably.
JP-A-9-059464 (page 2, pages 4-5) JP 2001-131398 A (second page) JP 2001-294742 A (2nd page) JP 2003-286414 A (page 2, pages 15-17)

  The present invention solves the above problems, has excellent regularity, and by finely controlling the structure thereof, without increasing the vinyl cyanide content in the composition, excellent mechanical properties, fluidity It is an object of the present invention to provide a styrenic resin composition that is useful as a molding material having good properties and chemical resistance.

  As a result of intensive studies to solve the above problems, the inventors of the present invention have (A) (a1) 20 to 75% by weight of a styrene monomer unit, (a2) 25 to 60% by weight of a vinyl cyanide monomer unit. %, And (a3) styrene-based resin containing 0 to 55% by weight of other vinyl monomer units copolymerizable therewith (however, the total of (a1) to (a3) is 100% by weight) ), And (B) a thermoplastic resin other than a styrene-based resin, and by controlling the structure to a two-phase continuous structure having a structural period of 0.001 to 1 μm, or a dispersed structure having a distance between particles of 0.001 to 1 μm, The inventors have found that the above problems can be solved and have completed the present invention.

That is, the present invention
(1) (A) (a1) 20 to 75% by weight of styrene monomer units, (a2) 25 to 60% by weight of vinyl cyanide monomer units, and (a3) other copolymerizable therewith Styrenic resin containing 0 to 55% by weight of vinylic monomer unit (however, the total of (a1) to (a3) is 100% by weight), and (B) thermoplastic resin other than styrene resin A styrenic resin composition characterized by having a biphasic continuous structure with a structural period of 0.001 to 1 μm, or a dispersed structure with a distance between particles of 0.001 to 1 μm,
(2) The copolymerizable (a3) vinyl-based monomer wherein the other vinyl-based monomer unit contains at least one functional group selected from a carboxyl group, a hydroxyl group, an epoxy group, an amino group, and an oxazoline group. A styrenic resin composition as described in (1) above, comprising a body unit;
(3) The above (1) or (2), wherein the (a1) styrenic monomer unit comprises a modified styrene monomer unit substituted with an alkyl group having 1 to 4 carbon atoms. Styrenic resin composition according to
(4) The styrenic resin composition according to any one of (1) to (3) above, wherein the thermoplastic resin other than the (B) styrenic resin is (b) a polycarbonate resin,
(5) The (b) polycarbonate resin comprises (b1) 2,2′-bis (4-hydroxyphenyl) propane and (b2) 2,2′-bis (4-hydroxy-3,5-dimethylphenyl) propane. 2,2′-bis (4-hydroxy-3,5-diethylphenyl) propane, at least one bifunctional selected from 2,2′-bis (4-hydroxy-3,5-dipropylphenyl) propane A styrene-based resin composition as described in (4) above, which comprises a copolymerized polycarbonate obtained by copolymerizing a phenol-based compound;
(6) (A) (a1) 20 to 75% by weight of styrene monomer units, (a2) 25 to 60% by weight of vinyl cyanide monomer units, and (a3) other copolymerizable with these Styrenic resin containing 0 to 55% by weight of vinylic monomer unit (however, the total of (a1) to (a3) is 100% by weight), and (B) thermoplastic resin other than styrene resin A method for producing a styrene resin composition according to any one of the above (1) to (5), wherein a styrene resin composition is obtained by melt-kneading
(7) The production method according to (6), wherein the melt-kneading is performed at a resin pressure of 2.0 MPa or more,
(8) The production method according to the above (6) or (7), characterized in that it is compatible under shear during the melt-kneading and phase-separated under non-shear after discharge,
(9) A molded product obtained by melt-molding the styrenic resin composition according to any one of (1) to (5) above,
It is.

  According to the present invention, by having excellent regularity and finely controlling the structure, a molded product having excellent mechanical properties, fluidity and chemical resistance can be obtained, and is practical as a general molding material. High styrene resin composition can be obtained.

  The resin composition of the present invention will be specifically described below.

  (A) Styrenic resin used in the present invention is (a1) a styrene-based monomer, (a2) a styrene-based copolymer obtained by polymerizing at a specific ratio using a vinyl cyanide monomer as an essential component, It is a styrene copolymer obtained by polymerizing the above component with a specific proportion of (a3) another vinyl monomer copolymerizable with these.

  (A1) As the styrene monomer, styrene is preferably used, but is substituted with an alkyl group having 1 to 4 carbon atoms from the viewpoint of improving compatibility by reducing the free volume under shear during melt kneading. It is preferable to use one or more modified styrenic monomers or to use this in combination with styrene. Examples of the modified styrene monomer include α-methyl styrene, p-methyl styrene, m-methyl styrene, o-methyl styrene, p-ethyl styrene, m-ethyl styrene, o-ethyl styrene, t-butyl styrene, and the like. In particular, α-methylstyrene, o-methylstyrene, and t-butylstyrene are preferably used.

  Examples of the (a2) vinyl cyanide monomer include acrylonitrile, methacrylonitrile and ethacrylonitrile, and acrylonitrile is particularly preferably used. These can use 1 type (s) or 2 or more types.

    In addition, (a3) other vinyl monomers that can be copolymerized with the components (a1) and (a2), which are used as necessary, are used for the purpose of improving toughness and color tone. ) For the purpose of improving the heat resistance of acrylic ester monomers and resin compositions, maleimide monomers are preferably used.

  Specific examples of the (meth) acrylic acid ester monomer include methyl, ethyl, propyl, n-butyl, and isobutyl esterified products of acrylic acid and methacrylic acid. In particular, methyl methacrylate is preferably used. .

  Specific examples of the maleimide monomer include maleimide, N-methylmaleimide and N-phenylmaleimide, and N-phenylmaleimide is particularly preferably used.

  In the present invention, from the viewpoint of further improving the compatibility of the components (A) and (B), (a3) other vinyl monomers copolymerizable with the components (a1) and (a2). As a copolymer, for example, a vinyl monomer containing at least one functional group selected from a carboxyl group, a hydroxyl group, an epoxy group, an amino group, and an oxazoline group can be copolymerized. A styrene copolymer obtained by copolymerizing a vinyl monomer containing such a functional group (hereinafter sometimes referred to as a modified styrene copolymer) can be preferably used.

  The modified styrene copolymer includes the above (a1) styrene monomer, (a2) vinyl cyanide monomer, and vinyl monomer containing the above functional group (a3) Examples include copolymers obtained by copolymerizing vinyl monomers, and (a3) other (meth) acrylic acid ester monomers and maleimide monomers as other vinyl monomers. Can be copolymerized.

    The content of the vinyl monomer containing these functional groups is not limited, but is preferably in the range of 0.01 to 20% by weight in 100% by weight of the modified styrene copolymer.

  The method for introducing a carboxyl group into the modified styrenic copolymer is not particularly limited, but carboxyl groups such as acrylic acid, methacrylic acid, maleic acid, maleic acid monoethyl ester, maleic anhydride, phthalic acid and itaconic acid. Or a method of copolymerizing a vinyl monomer having an anhydrous carboxyl group with a predetermined vinyl monomer containing the component (a1) and the component (a2), γ, γ'-azobis (γ-cyanovaleric acid), α , Α′-azobis (α-cyanoethyl) -p-benzoic acid and a polymerization initiator having a carboxyl group such as succinic acid peroxide and / or thioglycolic acid, α-mercaptopropionic acid, β-mercaptopropionic acid, α- Use of a polymerization degree regulator having a carboxyl group such as mercapto-isobutyric acid and 2,3 or 4-mercaptobenzoic acid And (co) polymerizing a predetermined vinyl monomer containing the component (a1) and the component (a2), and a (meth) acrylate monomer such as methyl methacrylate or methyl acrylate and styrene A method of saponifying a copolymer with a monomer and a vinyl cyanide monomer with an alkali can be used.

  The method for introducing the hydroxyl group is not particularly limited. For example, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 3-hydroxypropyl acrylate, 3-hydroxypropyl methacrylate, 2,3, acrylic acid 4,5,6-pentahydroxyhexyl, 2,3,4,5,6-pentahydroxyhexyl methacrylate, 2,3,4,5-tetrahydroxypentyl acrylate, 2,3,4,5-methacrylic acid Tetrahydroxypentyl, 3-hydroxy-1-propene, 4-hydroxy-1-butene, cis-4-hydroxy-2-butene, trans-4-hydroxy-2-butene, 3-hydroxy-2-methyl-1- Propene, cis-5-hydroxy-2-pentene, trans-5-hydroxy-2-pente And a method of copolymerizing a vinyl monomer having a hydroxyl group such as 4,4-dihydroxy-2-butene with a predetermined vinyl monomer containing the component (a1) and the component (a2). Can do.

  The method for introducing the epoxy group is not particularly limited. For example, epoxies such as glycidyl acrylate, glycidyl methacrylate, glycidyl ethacrylate, glycidyl itaconate, allyl glycidyl ether, styrene-p-glycidyl ether and p-glycidyl styrene A method of copolymerizing a vinyl monomer having a group with a predetermined vinyl monomer containing the component (a1) and the component (a2) can be used.

  Among them, an epoxy-modified styrene copolymer into which an epoxy group has been introduced by copolymerizing glycidyl methacrylate is used when (A) the styrene resin composition contains the styrenic resin composition of the present invention. Impact strength can be improved.

  The method for introducing the amino group is not particularly limited. For example, acrylamide, methacrylamide, N-methylacrylamide, butoxymethylacrylamide, N-propylmethacrylamide, aminoethyl acrylate, propylaminoethyl acrylate, dimethyl methacrylate. Amino groups such as aminoethyl, ethylaminopropyl methacrylate, phenylaminoethyl methacrylate, cyclohexylaminoethyl methacrylate, N-vinyldiethylamine, N-acetylvinylamine, allylamine, methallylamine, N-methylallylamine, p-aminostyrene And a method of copolymerizing a vinyl monomer having a derivative thereof and a predetermined vinyl monomer containing the component (a1) and the component (a2).

  The method for introducing the oxazoline group is not particularly limited. For example, a vinyl-based monomer having an oxazoline group such as 2-isopropenyl-oxazoline, 2-vinyl-oxazoline, 2-acryloyl-oxazoline, and 2-styryl-oxazoline. A method of copolymerizing the body with a predetermined vinyl monomer containing the component (a1) and the component (a2) can be used.

  (A) When copolymerizing a styrene resin, each component is copolymerized so that it may become the following copolymerization ratios. That is, the proportion of the (a1) styrene monomer unit is 20 to 75% by weight, preferably 30 to the total amount of the components (a1) to (a3) from the viewpoint of impact resistance of the resin composition. It is in the range of 75% by weight. (A2) The proportion of the vinyl cyanide monomer unit is 25 to 60% by weight, preferably 25 to 50% by weight, from the viewpoints of impact resistance, fluidity and chemical resistance. Furthermore, in the case of copolymerizing other vinyl monomer units copolymerizable with these (a3), they can be preferably used in the range of 0 to 55% by weight, preferably 0 to 50% by weight.

  Although there is no restriction | limiting in the characteristic of said (A) styrene resin, The intrinsic viscosity [(eta)] of the methyl ethyl ketone soluble part measured at 30 degreeC using the methyl ethyl ketone solvent is 0.20-2.00 dl / g, especially The thing of the range of 0.25-1.50dl / g is preferable from the resin composition which has the outstanding impact resistance and molding processability is obtained.

  (A) There is no restriction | limiting in particular in the manufacturing method of a styrene-type resin, Normal methods, such as a block polymerization method, a suspension polymerization method, an emulsion polymerization method, a solution polymerization method, a block-suspension polymerization method, and a solution-bulk polymerization method, are used. Can be used.

  Furthermore, the (A) styrenic resin used in the present invention preferably contains a rubber-containing graft copolymer in order to improve compatibility and impact resistance. Here, as the rubbery polymer used for the rubber-containing graft copolymer, those having a glass transition temperature of 0 ° C. or less are suitable, for example, diene rubber, acrylic rubber, ethylene rubber, and the like. As polybutadiene, poly (butadiene-styrene), poly (butadiene-acrylonitrile), polyisoprene, poly (butadiene-butyl acrylate), poly (butadiene-methyl acrylate), poly (butadiene-methyl methacrylate), poly (Butyl acrylate-methyl methacrylate), poly (butadiene-ethyl acrylate), ethylene-propylene rubber, ethylene-propylene-diene rubber, poly (ethylene-isobutylene), poly (ethylene-methyl acrylate) and the like. These rubbery polymers are used in one kind or a mixture of two or more kinds. Of these rubber polymers, polybutadiene, poly (butadiene-styrene), poly (butadiene-acrylonitrile), and ethylene-propylene rubber are particularly preferably used from the viewpoint of impact resistance.

  As monomers used in the rubber-containing graft copolymer of the present invention, (a1) styrene-based monomer and (a2) vinyl cyanide-based monomer are essential components, which can be copolymerized with these as optional components. (A3) Other vinyl monomers may be mentioned.

  (A1) Styrene monomers include styrene, α-methylstyrene, p-methylstyrene, m-methylstyrene, o-methylstyrene, p-ethylstyrene, m-ethylstyrene, o-ethylstyrene, t- Although butyl styrene etc. are mentioned, especially styrene is used preferably.

  Examples of the (a2) vinyl cyanide monomer include acrylonitrile, methacrylonitrile and ethacrylonitrile, and acrylonitrile is particularly preferably used.

  Further, (a3) other vinyl monomers copolymerizable with the components (a1) and (a2) used as necessary include methyl, ethyl, propyl, n- of acrylic acid and methacrylic acid. (Meth) acrylic acid ester monomers such as butyl and isobutyl esterified compounds and maleimide monomers such as maleimide, N-methylmaleimide and N-phenylmaleimide are preferably used.

  The content of the rubbery polymer used in the rubber-containing graft copolymer in the present invention is not particularly limited, but 5 to 80% by weight in the graft copolymer is preferable in terms of impact resistance, and more preferably 30 to 70. % By weight is preferred. Moreover, the ratio of the monomer mixture used in the rubber-containing graft copolymer is used so as to have the following copolymerization ratio from the viewpoint of impact resistance of the resin composition. That is, in the graft copolymer, the (a1) styrenic monomer unit is 20 to 75% by weight, preferably 30 to 75% by weight, based on the total of the components (a1) to (a3). (A2) The proportion of the vinyl cyanide monomer unit is 25 to 60% by weight, preferably 25 to 50% by weight, from the viewpoint of moldability of the resin composition. Furthermore, when (a3) another vinyl monomer unit is copolymerized, it is 0-55 weight, and the range of 0-50 weight% is used preferably. The total content of (a1) styrene monomer units, (a2) vinyl cyanide monomer units, and (a3) other vinyl monomer units in the graft copolymer is 95-20. It is preferable that it is weight%, More preferably, it is 70 to 30 weight%.

  The rubber-containing graft copolymer can be obtained by a known polymerization method. For example, it can be obtained by a method in which a mixture of a monomer mixture and a chain transfer agent and a solution of a radical generator dissolved in an emulsifier is continuously supplied to a polymerization vessel in the presence of a rubbery polymer latex and subjected to emulsion polymerization. it can.

  The graft (co) polymer contains a non-grafted copolymer in addition to a graft copolymer having a structure in which a monomer mixture is graft copolymerized with a rubbery polymer. The graft ratio of the graft (co) polymer is not particularly limited, but in order to obtain a resin composition having an excellent balance between impact resistance and gloss, it is in the range of 20 to 80% by weight, particularly 25 to 50% by weight. It is preferable that Here, the graft ratio is a value calculated by the following equation.

Graft rate (%) = [<Amount of vinyl copolymer graft-polymerized to rubbery polymer> / <Rubber content of graft copolymer>] × 100
The characteristics of the (co) polymer not graft-copolymerized are not particularly limited, but the intrinsic viscosity [η] (measured at 30 ° C.) of the methyl ethyl ketone-soluble component is 0.25 to 1.00 dl / g, particularly preferably 0.00. A range of 25 to 0.80 dl / g is a preferable condition for obtaining a resin composition having excellent impact resistance.

  Examples of the thermoplastic resin other than the (B) styrene resin of the present invention include (A) a thermoplastic resin capable of forming a phase structure defined in the present invention with the styrene resin, and examples thereof include polyester, polyamide, polyphenylene oxide, Polysulfone, Polytetrafluoroethylene, Polyetherimide, Polyamideimide, Polyimide, Polycarbonate, Polyethersulfone, Polyetherketone, Polythioetherketone, Polyetheretherketone, Epoxy resin, Phenolic resin, Polyethylene, Polypropylene, Polyphenylene sulfide, Polyamide elastomer , Polyester elastomer, polyalkylene oxide, or a resin such as an olefin copolymer containing a carboxyl group, etc., which can be used singly or in combination. , Preferably polyester, polyamide, polycarbonate, among them including polycarbonate resin for improving impact resistance and heat resistance, that is, using polycarbonate resin alone or other thermoplastic resin (preferably polyester, polyamide, etc.) ) Is most effective.

  The polycarbonate resin can be selected from aromatic homopolycarbonate and aromatic copolymer polycarbonate. As a production method, it can be produced by a known method, and an interfacial polycondensation method (so-called phosgene method) using bifunctional phenolic compounds such as 2,2′-bis (4-hydroxyphenyl) propane and phosgene as raw materials. Alternatively, a method such as a melt polymerization method (so-called transesterification method) in which the above-mentioned bifunctional phenolic compound and diphenyl carbonate are polymerized while performing a dephenol reaction under heating and melting can be employed.

  Here, the above bifunctional phenolic compounds are 2,2′-bis (4-hydroxyphenyl) propane, 2,2′-bis (4-hydroxy-3,5-dimethylphenyl) propane, bis (4-hydroxy). Phenyl) methane, 1,1′-bis (4-hydroxyphenyl) ethane, 2,2′-bis (4-hydroxyphenyl) butane, 2,2′-bis (4-hydroxy-3,5-diphenyl) butane 2,2′-bis (4-hydroxy-3,5-dipropylphenyl) propane, 1,1′-bis (4-hydroxyphenyl) cyclohexane, 1-phenyl-1,1′-bis (4-hydroxy) Phenyl) ethane and the like. In the present invention, the above bifunctional phenolic compounds may be used alone or in combination.

  In the present invention, (b1) an aromatic homopolycarbonate obtained by polymerizing 2,2′-bis (4-hydroxyphenyl) propane and an aromatic copolymer obtained by copolymerizing this with another bifunctional phenol compound. Polycarbonate is preferable, and it is also preferable to use these in combination. From the viewpoint of improving the compatibility by reducing the free volume under shear during melt-kneading, the aromatic copolymer polycarbonate may be (b1) 2,2′-bis (4-hydroxyphenyl) propane and (b2) 2,2. '-Bis (4-hydroxy-3,5-dimethylphenyl) propane, 2,2'-bis (4-hydroxy-3,5-diethylphenyl) propane, 2,2'-bis (4-hydroxy-3, An aromatic copolymer polycarbonate obtained by copolymerizing at least one bifunctional phenolic compound selected from 5-dipropylphenyl) propane and the like is preferable. Further, a polycarbonate resin containing this aromatic copolymer polycarbonate, that is, a polycarbonate resin used in combination with this aromatic copolymer polycarbonate alone or another polycarbonate, more preferably an aromatic homopolycarbonate obtained by polymerizing the above component (b1). Preferably there is.

    The aromatic polycarbonate preferably has a viscosity average molecular weight in the range of 10,000 to 100,000.

  (A) In alloying a styrene resin and a polycarbonate resin, (a2) the amount of vinyl cyanide copolymerization is reduced within a range not departing from the present invention, a modified styrene copolymer is added, or polycarbonate A desired phase structure as described below can be obtained by a method such as using an aromatic copolymer polycarbonate in combination with the above bifunctional phenolic compound as the resin. Furthermore, it becomes possible to know the structural control range easily by preparing a phase diagram with respect to the resin composition and temperature described later.

  The polyester resin that can be used as the component (B) is obtained by condensing an aromatic dicarboxylic acid or an ester thereof, or an ester-forming derivative and a diol by a known method, or obtained by condensing a hydroxycarboxylic acid. And copolymers thereof, and aromatic polyester, wholly aromatic polyester, liquid crystal polyester, and the like can be used. Here, examples of the aromatic dicarboxylic acid include naphthalene dicarboxylic acid such as naphthalene-2,6-dicarboxylic acid, terephthalic acid, and isophthalic acid. Examples of the hydroxycarboxylic acid include p-hydroxybenzoic acid, These ester-forming derivatives can also be used for the production of polyester resins. Examples of the diol include polymethylene glycol having 2 to 6 carbon atoms such as ethylene glycol, 1,4-butanediol, 1,6-hexanediol, or 1,4-cyclohexanediol, bisphenol A, and the like. Examples include ester-forming derivatives.

  Preferable specific examples of the polyester resin include polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polybisphenol A isophthalate and the like. The polyester resin preferably has an intrinsic viscosity at 25 ° C. in an o-chlorophenol solvent ([η] 25 ° C., measured in o-chlorophenol) of 0.4 to 2 dl / g, more preferably 0. .6 to 1.5 dl / g.

  (A) In alloying a styrene resin and a polyester resin, the compatibility region is expanded by lowering the molecular weight of the both or by adding the above-mentioned modified styrene copolymer. A phase structure can be obtained.

As said polyamide resin, what is normally manufactured by condensation of diamine and dicarboxylic acid, what is manufactured by ring-opening polymerization of a lactam, etc. can be used.
Preferable examples of these polyamide resins include nylon 6,6, nylon 6,9, nylon 6,10, nylon 6,12, nylon 6, nylon 12, nylon 11, nylon 4,6 and the like. Nylon 6 / 6,6, nylon 6 / 6,10, nylon 6/12, nylon 6 / 6,12, nylon 6 / 6,6 / 6,10, nylon 6 / 6,6 / 12, etc. Polymerized polyamides can also be used. Furthermore, semi-aromatic polyamides and polyesteramides obtained from nylon 6/6, T (T: terephthalic acid component), terephthalic acid, isophthalic acid and aromatic dicarboxylic acid and metaxylylenediamine, or alicyclic diamine Etc. can also be used. The polyamide resin preferably has a relative viscosity [η rel] measured in a 90% formic acid solvent at a concentration of 1 g / 100 cc and a temperature of 25 ° C. of 1.0 to 4.0, more preferably 1.5 to 3.5. belongs to. The above polyamide resins can be used singly or in combination of two or more.

  (A) In alloying a styrene resin and a polyamide resin, (A2) by increasing the vinyl cyanide content in the styrene resin, the SP (solubility parameter) values of both are approximated. By this method, the compatible region is expanded, and a desired phase structure can be easily obtained.

  Although there is no restriction | limiting in particular about the composition of the resin component which comprises the styrene resin composition in this invention, Usually (A) styrene resin with respect to a total of 100 weight% of the resin component which comprises a styrene resin composition Is preferably in the range of 20 to 95% by weight, more preferably in the range of 25 to 85% by weight, and particularly in the range of 30 to 80% by weight, since a biphasic continuous structure can be obtained relatively easily. Since the chemical resistance of the invention can be relatively easily obtained, it is preferably used.

  The styrenic resin composition of the present invention has excellent mechanical properties, molding processability, appearance by having a biphasic continuous structure with a structural period of 0.001 to 1 μm or a dispersed structure with a distance between particles of 0.001 to 1 μm. It exhibits mechanical properties, fluidity, and chemical resistance without impairing the properties.

  The styrenic resin composition of the present invention needs to have a two-phase continuous structure with a structural period of 0.001 to 1 μm or a dispersed structure with a distance between particles of 0.001 to 1 μm. In order to obtain such a structure, it is preferable that (A) the styrene-based resin and (B) the thermoplastic resin other than the styrene-based resin are once dissolved to form a structure by spinodal decomposition described later. Furthermore, in order to realize this structure formation, (A) a styrene resin and (B) a thermoplastic resin other than the styrene resin undergo a partial miscibility system, which will be described later, or a shear field-dependent phase dissolution / phase decomposition. A system is preferred.

  In general, polymer alloys composed of two-component resins are compatible with these compositions in a practical system where the glass transition temperature is higher than the thermal decomposition temperature or lower, and vice versa. There are incompatible systems that dissolve, and partially compatible systems that are compatible in one region and phase separated in another region. In this partially compatible system, phase separation is performed by spinodal decomposition depending on the conditions of the phase separated state. And phase separation by nucleation and growth.

  Furthermore, in the case of a polymer alloy composed of three or more components, a system in which all three or more components are compatible, a system in which all three or more components are incompatible, a compatible phase having two or more components, and the rest There is a system in which one or more phases are incompatible, two components are partially compatible, and the remaining components are distributed in a partially compatible system composed of these two components. The polymer alloy composed of 3 or more components preferred in the present invention is a system in which 2 components are partially compatible and the remaining components are distributed to the partially compatible system composed of 2 components. In this case, the structure of the polymer alloy is 2 Since it can be replaced by a partially compatible structure composed of components, the following description will be made on behalf of a polymer alloy composed of a two-component resin.

Phase separation by spinodal decomposition refers to phase separation that occurs in an unstable state inside the spinodal curve in phase diagrams for different two-component resin compositions and temperatures, and phase separation by nucleation and growth refers to the phase separation. In the figure, it refers to phase separation that occurs in the metastable state inside the binodal curve and outside the spinodal curve.
The spinodal curve refers to the difference (ΔGmix) between the free energy when compatibilized and the sum of the free energies in two phases that are not compatible (ΔGmix) when two different resins are mixed with respect to the composition and temperature. φ) partial differential twice (∂2ΔGmix
/ ∂φ2) is a curve with 0, and inside the spinodal curve, 不 安定 2ΔGmix / ∂φ2 <0 is in an unstable state and outside is ∂2ΔGmix / ∂φ2> 0.
The binodal curve is a boundary curve between the region where the system is compatible and the region where the system is separated with respect to the composition and temperature.

Here, the case of being compatible in the present invention is a state in which they are uniformly mixed at the molecular level. Specifically, both phases having different two-component resins as main components are 0.001 μm or more. The case where the phase structure is not formed is indicated, and the case where the phase is incompatible is the case where the phase is not in a compatible state, that is, the phases mainly composed of two different resin components are 0.001 μm or more. It refers to the state of forming a phase structure. Whether or not they are compatible is determined by an electron microscope, a differential scanning calorimeter (DSC), and various other methods as described in Polymer Alloys and Blends, Leszek A Utracki, hanser Publishers, Munich Viema New York, P64, for example. can do.

  According to detailed theory, in spinodal decomposition, once the temperature of a mixed system that has been uniformly mixed at the temperature of the compatible region is rapidly increased to the temperature of the unstable region, the system will rapidly phase-separate toward the coexisting composition. To start. At that time, the concentration is monochromatized at a constant wavelength, and a two-phase continuous structure is formed in which both separated phases are continuously intertwined regularly with a structure period (Λm). After the formation of the two-phase continuous structure, the process in which only the concentration difference between the two phases increases while keeping the structure period constant is called the initial process of spinodal decomposition.

Furthermore, the structural period (Λm) in the initial process of the above-mentioned spinodal decomposition has a thermodynamic relationship as shown in the following equation.
Λm to [│Ts-T│ / Ts] ^-1/2 (where Ts is the temperature on the spinodal curve)
Here, the two-phase continuous structure referred to in the present invention refers to a structure in which both components of the resin to be mixed each form a continuous phase and are entangled three-dimensionally. A schematic diagram of this two-phase continuous structure is described, for example, in “Polymer Alloy Fundamentals and Applications (Second Edition) (Chapter 10.1)” (edited by the Society of Polymer Science: Tokyo Kagaku Dojin)

  In spinodal decomposition, after going through such an initial process, it goes through a medium-term process in which an increase in wavelength and an increase in concentration difference occur simultaneously, and a later process in which an increase in wavelength occurs in a self-similar manner after the concentration difference reaches the coexisting composition. In order to obtain the structure defined in the present invention, the desired structural period before the final separation into the macroscopic two phases has been reached. What is necessary is just to fix a structure in a step.

  In addition, in the process of increasing the wavelength from the mid-stage process to the late-stage process, depending on the influence of the composition and the interfacial tension, the continuity of one phase may be interrupted and the above-described biphasic continuous structure may be changed to a dispersed structure. In this case, the structure may be fixed when the desired interparticle distance is reached.

  Here, the dispersion structure referred to in the present invention is a so-called sea-island structure in which particles mainly composed of the other resin component are interspersed in a matrix mainly composed of one resin component. Point.

  The styrenic resin composition of the present invention must be structurally controlled to have a two-phase continuous structure with a structural period of 0.001 to 1 μm or a dispersed structure with a distance between particles of 0.001 to 1 μm. In order to obtain better mechanical properties, it is possible to control the structure to have a two-phase continuous structure with a structural period of 0.01 to 0.5 μm or a dispersed structure with a distance between particles of 0.01 to 0.5 μm. More preferably, it is more preferable to control the two-phase continuous structure in the range of the structural period of 0.01 to 0.4 μm or the dispersed structure in the range of the interparticle distance of 0.01 to 0.4 μm, and extremely excellent characteristics. In order to obtain the above, it is most preferable to control to a two-phase continuous structure having a structural period of 0.01 to 0.3 μm or a dispersed structure having a distance between particles of 0.01 to 0.3 μm. A structure having excellent mechanical properties, fluidity, and chemical resistance, which are the effects of the present invention, can be effectively obtained by controlling the structure period and the interparticle distance.

  On the other hand, in the nucleation and growth, which is the phase separation in the metastable region described above, a dispersed structure that is a sea-island structure is formed from the initial stage, and it grows. It is difficult to form a biphasic continuous structure in the range of 0.001 to 1 μm or a dispersed structure in the range of a distance between particles of 0.001 to 1 μm.

Moreover, in order to confirm the biphasic continuous structure by these spinodal decompositions or a disperse structure, it is important to confirm a regular periodic structure. For example, in addition to confirming that a two-phase continuous structure is formed by observation with an optical microscope or a transmission electron microscope, the scattering maximum in a scattering measurement performed using a light scattering device or a small-angle X-ray scattering device Confirmation of appearing is necessary. Note that the light scattering device and the small-angle X-ray scattering device have different optimum measurement regions, so that they are appropriately selected according to the size of the structure period. The existence of the scattering maximum in this scattering measurement is a proof that there is a regular phase separation structure with a certain period, and its period Λm corresponds to the structure period in the case of the biphasic continuous structure, and the interparticle distance in the case of the dispersion structure. Correspond. The value can be calculated by the following equation using the wavelength λ of the scattered light in the scatterer and the scattering angle θm that gives the scattering maximum.
Λm = (λ / 2) / sin (θm / 2)
In order to realize the spinodal decomposition, it is necessary to make the styrenic resin and the thermoplastic resin other than the styrenic resin compatible with each other, and then make the unstable state inside the spinodal curve.

  First, as a method of realizing a compatible state with a resin composed of two or more components, after dissolving in a common solvent, spray drying, freeze drying, coagulation in a non-solvent substance, film formation by solvent evaporation, etc. from this solution is used. Examples thereof include a solvent casting method and a melt-kneading method in which a partially compatible system is melt-kneaded under compatible conditions. Among these, compatibilization by melt kneading, which is a dry process that does not use a solvent, is preferably used in practice.

  For compatibilization by melt kneading, an ordinary extruder is used, but a twin screw extruder is preferably used. Further, depending on the combination of resins, there are cases where compatibilization can be achieved in the plasticizing process of the injection molding machine. The temperature for compatibilization needs to be a condition in which the partially compatible resin is compatible.

  Next, when the resin composition made into a compatible state by the above melt kneading is in an unstable state inside the spinodal curve, the temperature for making the unstable state when the spinodal decomposition is performed, and other conditions vary depending on the combination of the resins. Although it cannot be generally stated, it can be set by performing a simple preliminary experiment based on the phase diagram.

  As a method of immobilizing the structure product by spinodal decomposition, one or both components of the phase-separated phase can be fixed in a short period of time by rapid cooling or the like, or if one is a component that is thermosetting, the phase of the thermosetting component May be fixed by utilizing the fact that they cannot move freely due to reaction, and when the other is a crystalline resin, it may be fixed by utilizing the fact that the crystalline resin phase cannot be freely moved by crystallization.

  In the present invention, (A) the styrene resin and (B) the thermoplastic resin other than the styrene resin are phase-separated by the above spinodal decomposition to obtain the styrene resin composition of the present invention as described above (A It is preferable to combine a styrene resin and a resin that is a partially compatible system or a shear field-dependent phase dissolving / phase-decomposing system.

  In general, partial compatible systems are known to have a low-temperature compatible phase diagram that is easy to be compatible on the low temperature side in the same composition, and a high temperature compatible phase diagram that is easy to be compatible on the high temperature side. It has been. The lowest temperature between the compatible and incompatible branching temperatures in this low-temperature compatible phase diagram is called the lower critical solution temperature (LCST for short). The highest incompatible branch temperature is called the upper critical solution temperature (UCST).

  In the case of a low-temperature compatible phase diagram, a resin of two or more components that have become compatible using a partially compatible system can be brought to a temperature higher than the LCST and a temperature inside the spinodal curve. In the case of the figure, spinodal decomposition can be performed by setting the temperature below UCST and the temperature inside the spinodal curve.

  In addition to spinodal decomposition by this partially compatible system, spinodal decomposition is also induced by melt kneading in non-compatible systems, for example, once compatible under shearing during melt kneading, etc., and then in an unstable state again under non-shearing. Phase separation by spinodal decomposition is also possible by so-called shear field-dependent phase dissolution / phase decomposition in which phase decomposition occurs, and in this case as well, in the same manner as in the case of a partially miscible system, decomposition proceeds in a spinodal decomposition mode and both phases are ordered. Has a continuous structure. Furthermore, this shear field-dependent phase dissolution / phase decomposition is the same as the method based on the temperature change of the partially miscible system in which the spinodal curve does not change because the spinodal curve changes due to the shear field and the unstable region expands. The substantial degree of supercooling (| Ts−T |) also increases in the temperature change range, and as a result, it is easy to reduce the structural period in the initial process of spinodal decomposition in the above relational expression, so that it is preferably used. It is done. In order to achieve compatibilization by shearing during such melt kneading, a normal extruder is used, but a twin screw extruder is preferably used. Further, depending on the combination of resins, there are cases where compatibilization can be achieved in the plasticizing process of the injection molding machine. In this case, the temperature for compatibilization, the heat treatment temperature for forming the initial process, the heat treatment temperature for developing the structure from the initial process, and other conditions differ depending on the combination of the resins, and cannot be generally stated. The conditions can be set by performing a simple preliminary experiment based on the phase diagram under the shear conditions. Also, as a method of reliably realizing the compatibilization in the plasticizing process of the injection molding machine, it is melt-kneaded with a twin-screw extruder in advance and compatibilized, and after discharging, it is rapidly cooled in ice water or the like to fix the structure in the compatibilized state. A preferred example is a method of injection molding using a paste.

  In addition, the addition of the third component, which is a copolymer such as a block copolymer, a graft copolymer, or a random copolymer, that further includes a component constituting the polymer alloy to the styrene resin composition constituting the present invention is performed between the phase-decomposed phases. In order to reduce the free energy of the interface, it is preferably used in order to easily control the structural period in the biphasic continuous structure and the distance between dispersed particles in the dispersed structure. In this case, the third component such as the copolymer is usually distributed to each phase of the polymer alloy composed of the two-component resin except the copolymer, and thus can be handled in the same manner as the polymer alloy composed of the two-component resin.

  Since the styrene resin composition containing (A) styrene resin and (B) thermoplastic resin used in the present invention has a large amount of highly polar vinyl cyanide monomer, it is melt-processed by a conventional method. Attempting to do so deteriorates melt processability, greatly reducing the mechanical properties of the resulting composition. However, if the melt-kneading is performed under high shear at a resin pressure of 2.0 MPa or more, the above-described specific phase separation structure can be stably obtained under practical molding conditions.

    The resin pressure in the production method of the present invention is a value measured with a resin pressure gauge attached to the melt-kneading apparatus, and the gauge pressure is taken as the resin pressure.

  The resin pressure at the time of melt kneading does not need to be consistently 2.0 MPa or more, and it is sufficient that at least one place or a region or time in which the resin pressure temporarily becomes 2.0 MPa or more exists at the time of melt kneading. When melt-kneading using an extruder, it is preferable that the resin pressure be 2.0 MPa or more at a location where the resin pressure is usually highest, for example, at a resin residence location due to reverse full flight or kneading block. . In the present invention, it is sufficient that at least one or more regions where the resin pressure is 2.0 MPa or more exist when melt-kneading (A) the styrene resin and (B) the thermoplastic resin other than the styrene resin. Since the resin pressure tends to increase in resin stays due to reverse full flight and kneading blocks in the melt-kneading device, the resin pressure at these resin stays is measured so that the resin pressure becomes 2.0 MPa or more. What is necessary is just to melt-knead on the conditions. In the present invention, it is sufficient that there is a time during which the resin pressure temporarily becomes 2.0 MPa or more during melt kneading. Here, the time during which the resin pressure becomes 2.0 MPa or more is preferably 1 second or more, and the resin stays temporarily for 1 second or more in the resin staying place by reverse full flight or kneading block, so that the resin pressure temporarily There will be a time when the pressure becomes 2.0 MPa or more. The time for the resin pressure to become 2.0 MPa or more is more preferably about 5 seconds to 5 minutes.

  The resin pressure at the time of melt kneading is not particularly limited as long as the mechanical performance allows as long as the pressure is 2.0 MPa or more, but it is preferably used in the range of 2.0 to 10.0 MPa, and more preferably 2.0 to 7.0 MPa. In particular, a range of 2.0 to 5.0 MPa is preferably used because a two-phase continuous structure can be obtained more stably and the deterioration of the resin is small. The resin pressure is indicated, for example, by a gauge pressure of a resin pressure gauge provided in an arbitrary barrel portion such as a full flight portion, a kneading block portion, or a front portion of a discharge port when melt kneading using an extruder. Value.

  The method for adjusting the resin pressure at the time of melt kneading is not particularly limited. For example, (b) improvement of the resin viscosity by lowering the melt kneading temperature, (b) selection of a polymer having a molecular weight that achieves the desired resin pressure. (C) Resin retention due to screw arrangement change such as reverse full flight, introduction of kneading block, (d) Increase the polymer filling rate in the barrel, (e) Increase screw rotation speed, (f) Optional additives (G) supercritical state such as introduction of carbon dioxide gas.

    When melt-kneading the styrene-based resin composition of the present invention, the barrel temperature, the screw rotation speed, and the raw material supply rate (in order that the resin pressure is in the range of 2.0 MPa or more, preferably 2.0 to 10.0 MPa ( It is preferable to manufacture by adjusting the filling rate) and the resin temperature.

  Furthermore, in the present invention, a filler may be used as necessary in order to improve strength, dimensional stability, and the like. The filler may be fibrous or non-fibrous, or a combination of fibrous filler and non-fibrous filler may be used. Examples of the filler include glass fiber, glass milled fiber, carbon fiber, potassium titanate whisker, zinc oxide whisker, aluminum borate whisker, aramid fiber, alumina fiber, silicon carbide fiber, ceramic fiber, asbestos fiber, stone-kow fiber, metal Fibrous fillers such as fibers, wollastonite, zeolite, sericite, kaolin, mica, clay, pyrophyllite, bentonite, asbestos, talc, alumina silicate and other silicates, alumina, silicon oxide, magnesium oxide, zirconium oxide, Metal compounds such as titanium oxide and iron oxide, carbonates such as calcium carbonate, magnesium carbonate and dolomite, sulfates such as calcium sulfate and barium sulfate, hydroxides such as magnesium hydroxide, calcium hydroxide and aluminum hydroxide, Rasubizu, ceramic beads, non-fibrous fillers such as boron nitride and silicon carbide and the like, which may be hollow, it is also possible to further combination of these fillers 2 or more. In addition, these fibrous and / or non-fibrous fillers are pretreated with a coupling agent such as an isocyanate compound, an organic silane compound, an organic titanate compound, an organic borane compound, an epoxy compound, It is preferable in terms of obtaining superior mechanical strength.

  In order to improve strength, dimensional stability, etc., when such a filler is used, the blending amount thereof is not particularly limited, but is usually 0.1 to 100 parts by weight in total of the component (A) and the component (B). 200 parts by weight is preferably blended.

  As long as the effects of the present invention are not impaired, the styrene-based resin composition of the present invention includes plasticizers such as polyalkylene oxide oligomer compounds, thioether compounds, ester compounds, and organic phosphorus compounds, talc, kaolin, and organic phosphorus compounds. , Nucleating agents such as polyether ether ketone, polyolefin compounds, silicone compounds, long chain aliphatic ester compounds, long chain aliphatic amide compounds, mold release agents, anticorrosives, anti-coloring agents, antioxidants Ordinary additives such as a lubricant, a flame retardant, a heat stabilizer, a lubricant such as lithium stearate and aluminum stearate, an anti-UV agent, a colorant and a foaming agent can be added.

  These additives can be blended at any stage for producing the styrenic resin composition of the present invention. For example, a method of simultaneously adding at least two components of a resin, or two components in advance. There are a method of adding the resin after melt kneading, and a method of adding the resin to one resin first and then melt-kneading and then blending the remaining resin.

  The molding method of the styrene resin composition obtained from the present invention can be any method, and the molding shape can be any shape. Examples of the molding method include injection molding, extrusion molding, inflation molding, blow molding and the like. Among them, injection molding is preferable because heat treatment and structural fixation can be simultaneously performed in the mold after injection. If it is and / or sheet extrusion molding, heat treatment is preferably performed when the film and / or sheet is stretched, and the structure can be fixed during natural cooling before subsequent winding. Of course, it is possible to heat-treat the molded product separately to form a structure.

    The styrenic resin composition in the present invention can be usefully used as a structural material by taking advantage of excellent mechanical properties, fluidity, and chemical resistance. For example, electrical / electronic parts, automobile parts, mechanical mechanism parts, OA equipment. It can be suitably used for housings such as home appliances, parts thereof, and miscellaneous goods.

    The molded body of the styrene resin composition of the present invention includes, for example, various gears, various cases, sensors, LED lamps, connectors, sockets, resistors, relay cases, switches, coil bobbins, capacitors, variable capacitor cases, optical pickups, and oscillators. Terminal boards, transformers, plugs, printed wiring boards, tuners, speakers, microphones, headphones, small motors, magnetic head bases, power modules, housings, semiconductors, liquid crystals, FDD carriages, FDD chassis, motor brush holders, parabolic antennas Electric / electronic parts represented by computer-related parts; generators, motors, transformers, current transformers, voltage regulators, rectifiers, inverters, relays, power contacts, switches, circuit breakers, knife switches, etc. Polar rod, electrical parts key Vignette, VTR parts, TV parts, irons, hair dryers, rice cooker parts, microwave oven parts, acoustic parts, audio / laser discs / compact discs, audio equipment parts such as DVDs, lighting parts, refrigerator parts, air conditioner parts, typewriters Houses represented by parts, word processor parts, office electrical product parts, office computer related parts, telephone related parts, mobile phone related parts, facsimile related parts, copying machine related parts, cleaning jigs, oilless bearings, stern bearings Various bearings such as underwater bearings, motor-related parts such as motor parts, lighters and typewriters, optical equipment such as microscopes, binoculars, cameras and watches, precision machine-related parts; alternator terminals, alternator connectors IC regulation Potentiometer base for light deer, air intake nozzle snorkel, intake manifold, air flow meter, air pump, fuel pump, engine coolant joint, thermostat housing, carburetor main body, carburetor spacer, engine mount, ignition hobbin, ignition case , Clutch bobbin, sensor housing, idle speed control valve, vacuum switching valve, ECU housing, vacuum pump case, inhibitor switch, rotation sensor, acceleration sensor, distributor cap, coil base, actuator case for ABS, top and bottom of radiator tank , Cooling fan, fan shroud, en Gin cover, cylinder head cover, oil cap, oil pan, oil filter, fuel cap, fuel strainer, distributor cap, vapor canister housing, air cleaner housing, timing belt cover, brake booster parts, various cases, fuel related / exhaust system Various tubes such as intake systems, various tanks, various hoses such as fuel / exhaust systems / intake systems, various clips, various valves such as exhaust gas valves, various pipes, exhaust gas sensors, cooling water sensors, oil temperature sensors, brake pads Wear sensor, brake pad wear sensor, throttle position sensor, crankshaft position sensor, thermostat base for air conditioner, air conditioner panel switch board, heating hot air Low control valve, brush holder for radiator motor, water pump impeller, turbine vane, wiper motor related parts, step motor rotor, brake piston, solenoid bobbin, engine oil filter, ignition device case, torque control lever, starter switch, starter relay, Safety belt parts, register blades, washer levers, window regulator handles, knobs for window regulator handles, passing light levers, distributors, sun visor brackets, various motor housings, roof rails, fenders, garnishes, bumpers, door mirror stays, horn terminals, Window washer nozzle, spoiler, hood louver Wheel cover, wheel cap, radiator grille, grill apron cover frame, lamp reflector, lamp socket, lamp housing, lamp bezel, door handle and other automotive exterior materials, center console, instrument panel, instrument panel core, instrument panel pad, glove box, Automotive parts such as handle columns, armrests, lever parking, front pillar trims, door trims, pillar trims, console boxes, and other automotive interior materials, wire harness connectors, SMJ connectors, PCB connectors, door grommets connectors, and connectors for fuses; , Printer, display, CRT display, fax, copy, word processor, laptop, mobile phone , PHS, DVD drive, PD drive, flexible disk drive and other storage device housings, chassis, relays, switches, case members, transformer members, coil bobbins and other electrical and electronic equipment parts, machine parts, and other various uses .

  In order to describe the present invention more specifically, examples and comparative examples will be described below, but the present invention is not limited to these examples. In the examples, parts and% indicate parts by weight and% by weight, respectively.

[Reference Example 1] (A) Styrenic resin <ST-1> Preparation of vinyl copolymer A method for preparing a vinyl copolymer is shown below. The polymer obtained was dried under reduced pressure at 70 ° C. for 5 hours, and then a methyl ethyl ketone solution having a concentration of 0.4 g / 100 ml was prepared, and the intrinsic viscosity was measured using an Ubbelohde viscometer at 30 ° C.

  Moreover, about the content rate of each monomer unit in the obtained vinyl-type copolymer, the film-form sample of about 30 micrometers was created by press molding, and it measured by FT-IR analysis.

<ST-1-1>
A styrene-acrylonitrile copolymer “Toyolac” 1050B (manufactured by Toray Industries, Inc.) was used. The intrinsic viscosity of the soluble part of methyl ethyl ketone was 0.39 dl / g, and the content of each monomer unit was 77% by weight of styrene units and 23% by weight of acrylonitrile units.

<ST-1-2>
A monomer mixture consisting of 70% styrene and 30% acrylonitrile was suspension-polymerized to prepare a vinyl copolymer. The vinyl copolymer obtained had an intrinsic viscosity of 0.53 dl / g of the methyl ethyl ketone-soluble component, and the content of each monomer unit was 71% by weight of styrene units and 29% by weight of acrylonitrile units.

<ST-1-3>
A monomer mixture composed of 65% styrene and 35% acrylonitrile was suspension-polymerized to prepare a vinyl copolymer. The vinyl copolymer obtained had an intrinsic viscosity of 0.54 dl / g of the methyl ethyl ketone-soluble component, and the content of each monomer unit was 66% by weight of styrene units and 34% by weight of acrylonitrile units.

<ST-1-4>
A monomer mixture consisting of 60% styrene and 40% acrylonitrile was suspension-polymerized to prepare a vinyl copolymer. The obtained vinyl copolymer had an intrinsic viscosity of 0.51 dl / g of methyl ethyl ketone-soluble component, and the content of each monomer unit was 61% by weight of styrene units and 39% by weight of acrylonitrile units.

<ST-1-5>
A monomer mixture composed of 40% styrene, 30% acrylonitrile, and 30% α-methylstyrene was subjected to suspension polymerization to prepare a vinyl copolymer. The vinyl copolymer obtained had an intrinsic viscosity of 0.52 dl / g of methyl ethyl ketone-soluble component, each monomer unit content of 40% by weight of styrene unit, 31% by weight of acrylonitrile unit, and α-methylstyrene unit. It was 29% by weight.

<ST-1-6>
A monomer mixture composed of 69.7% styrene, 30% acrylonitrile, and 0.3% glycidyl methacrylate was subjected to suspension polymerization to prepare a modified vinyl copolymer. The resulting modified vinyl copolymer has an intrinsic viscosity of 0.53 dl / g for the soluble part of methyl ethyl ketone, the content of each monomer unit is 70.6% by weight of styrene units, 29% by weight of acrylonitrile units, and glycidyl methacrylate. The unit was 0.4% by weight.

<ST-1-7>
A monomer mixture consisting of 67% styrene, 30% acrylonitrile and 3% maleic anhydride was solution polymerized in a methyl ethyl ketone solvent to prepare a vinyl copolymer. The obtained vinyl copolymer had an intrinsic viscosity of 0.53 dl / g of methyl ethyl ketone-soluble component, the content of each monomer unit was 67% by weight of styrene units, 30% by weight of acrylonitrile units, and 3 units of maleic anhydride units. % By weight.

<ST-2> Rubber-containing graft copolymer A method for preparing a rubber-containing graft copolymer is shown below. The graft ratio was determined by the following method. Acetone was added to a predetermined amount (m) of the graft copolymer and refluxed for 4 hours. This solution was centrifuged at 8000 rpm (centrifugal force 10,000 G (about 100 × 10 ³ m / s ² )) for 30 minutes, and the insoluble matter was filtered off. This insoluble matter was dried under reduced pressure at 70 ° C. for 5 hours, and the weight (n) was measured.

Graft ratio = [(n) − (m) × L] / [(m) × L] × 100
Here, L means the rubber content of the graft copolymer.
The filtrate of the acetone solution was concentrated with a rotary evaporator to obtain a precipitate (acetone soluble matter). The soluble matter was dried under reduced pressure at 70 ° C. for 5 hours, a 0.4 g / 100 ml concentration methyl ethyl ketone solution was prepared, and the intrinsic viscosity was measured using an Ubbelohde viscometer under a temperature condition of 30 ° C.

    Moreover, about the content rate of each monomer unit in the obtained graft copolymer, the film-form sample about 30 micrometers was created by press molding, and it measured by FT-IR analysis.

<ST-2-1>
In the presence of 50 parts of polybutadiene latex (average rubber particle size 0.3 μm) (in terms of solid content), 50 parts of a monomer mixture composed of 70% styrene and 30% acrylonitrile was added to carry out emulsion polymerization. The obtained graft copolymer was solidified with sulfuric acid, washed and dried to obtain a powder.

  The graft ratio of the obtained graft copolymer was 42%, the intrinsic viscosity of methyl ethyl ketone soluble matter was 0.37 dl / g, the content of each monomer unit was 50% by weight of butadiene units, 35% by weight of styrene units, The acrylonitrile unit was 15% by weight.

[Reference Example 2] (B) Thermoplastic resin other than styrene resin <PC-1> Aromatic polycarbonate “Iupilon” S3000 (manufactured by Mitsubishi Engineering Plastics) (2,2′-bis (4-hydroxyphenyl) Propane polymer) was used.

  <PC-2> Aromatic polycarbonate “Iupilon” S2000 (manufactured by Mitsubishi Engineering Plastics) (polymer of 2,2′-bis (4-hydroxyphenyl) propane) was used.

  <PC-3> 2,2'-bis (4-hydroxyphenyl) propane 24.3%, 2,2'-bis (4-hydroxy-3,5-dimethylphenyl) propane 30.6%, and diphenyl carbonate 45.1% was charged into a stirring tank and purged with nitrogen and melted at 150 ° C. Tetramethylammonium hydroxide and sodium hydroxide were added thereto, and the reaction was carried out by stirring at 150 ° C. for 1 hour. Next, the temperature was raised to 220 ° C., the pressure was reduced to 27 kPa (200 mmHg), and the mixture was stirred for 1 hour. The temperature was further raised to 250 ° C., the pressure was reduced to 2 kPa (15 mmHg), and the reaction was allowed to proceed by stirring for 1 hour. The obtained reaction product was sent to a centrifugal thin film evaporator and allowed to proceed, and then sent to a horizontal stirring polymerization device to complete the polymerization by staying at 290 ° C. for 30 minutes. Copolymerized aromatic polycarbonate which was made into a strand shape through a die from a horizontal stirrer and pelletized with a cutter was used.

[Reference Example 3] Additive <TZ-1> A phosphite antioxidant “ADK STAB” PEP-8 (Asahi Denka Kogyo Co., Ltd.) was used.

[Examples 1 to 15]
The raw material which consists of a composition of Examples 1-15 of Table 1 was supplied to the twin screw extruder (Ikegai Kogyo Co., Ltd. PCM-30) which has a kneading block part. In the extrusion using an extruder, the barrel temperature was adjusted between 220 ° C. and 250 ° C. so that the resin pressure in the kneading block at the time of melt kneading became the value shown in Table 1. The gut discharged from the die was immediately cooled in ice water, fixed the structure, and pelletized to produce pellets. The resin pressure is a value indicated by a gauge pressure of a resin pressure gauge provided at the kneading portion of the extruder barrel. The values are shown in Table 1. Using the obtained pellets, each test piece was molded by an injection molding machine (manufactured by Sumitomo Heavy Industries Co., Ltd., Promat 40/25) at an injection pressure of lower limit pressure + 1 MPa, and physical properties were measured under the following conditions.

[Content of Vinyl Cyanide Monomer Unit in Composition] The content of the vinyl cyanide compound in the obtained composition was such that a film-like sample of about 30 μm was prepared by press molding, and FT-IR. Measured by analysis
[Impact resistance]: The impact resistance was evaluated according to ASTM D256-56A.

  [Heat resistance]: Heat resistance was evaluated according to ASTM D648 (load: 1.82 MPa).

  [Flowability]: The flow length (spiral flow length) of spiral flow (cross-sectional shape: width 10 mm × thickness 2 mm) was measured at a cylinder temperature of 240 ° C., a mold temperature of 60 ° C., and an injection pressure of 50 MPa.

[Chemical resistance] 1/8 "(approx. 3.2 mm) thick bending test specimens are left in the chemicals shown below at 23 ° C for 7 days (by gently rotating the whole container by hand every 24 hours, stirring the chemicals in it) After that, the test piece taken out from the chemical solution was washed with running water, conditioned in air at 23 ° C. and 50% RH for 7 days, and the bending test was evaluated according to ASTM D790 with the chemical solution removed, before and after immersion in the chemical solution. The bending elastic modulus retention at was obtained.
(1) 10% sulfuric acid aqueous solution
(2) 30% sodium hydroxide aqueous solution
(3) Methanol
(4) Thinner In addition, a gut with a fixed structure and a sample obtained by cutting a 100 μm-thick section from the molded product obtained by injection molding after ultra-thin section after staining with polycarbonate by iodine staining method. The sample cut out was observed at a magnification of 100,000 times with a transmission electron microscope.

In addition, with respect to a sample obtained by quenching in ice water and fixing a structure and cutting a 100 μm-thick section from a molded product obtained by injection molding, the structure period in the case of a two-phase continuous structure or the particles in the case of a dispersed structure The inter-space distance was measured by small-angle X-ray scattering (in the case of a structure period or interparticle distance of less than 0.4 μm) or light scattering (in the case of a structure period or interparticle distance of 0.4 μ or more). Peaks were observed in all samples, and the structure period or interparticle distance (Λm) calculated by the following equation from the peak position (θm) was described.
Λm = (λ / 2) / sin (θm / 2)
From the transmission electron micrograph of each sample, the structural state, the structural period or interparticle distance from small angle X-ray scattering or light scattering, and the impact resistance, heat resistance, fluidity, and chemical resistance measurement results are shown. It is shown in 1.

  From Examples 1 to 15, in the styrene resin composition of the present invention using a styrene resin having a large amount of vinyl cyanide monomer, a two-phase continuous structure of 1 μm or less and a fine phase structure which is a dispersed structure are put into practical use. It can be obtained stably in typical injection molding, and the impact resistance, heat resistance, fluidity, and chemical resistance can be drastically improved. In particular, as shown in Example 10, even in a region where the amount of vinyl cyanide in the composition due to the increase in the polycarbonate content is small compared to Comparative Example 2, it has high chemical resistance due to the specific phase structure. I understand that.

  Furthermore, when <ST-2-1> rubber-containing graft copolymer is added, not only the impact resistance is improved but also the chemical resistance is not lowered, so that a practical composition can be designed.

[Comparative Examples 1-4]
The raw material which consists of a composition of the comparative examples 1 and 2 of Table 2 was supplied to the twin screw extruder (Ikegai Kogyo Co., Ltd. PCM-30) which set the barrel temperature to 250 degreeC. The gut discharged from the die was immediately cooled in ice water to fix the structure, and then a pellet-like polymer was produced (the resin pressure in Comparative Example 2 at this time was 1.5 MPa). Moreover, the raw material which consists of a composition of the comparative examples 3 and 4 is supplied to the single screw extruder (VS40-32 by Tanabe Plastics machine Co., Ltd.) set to the extrusion temperature of 280 degreeC, and the gut after discharge from a die is immediately After rapidly cooling in ice water and fixing the structure, a pellet-shaped polymer was produced (the resin pressure in Comparative Example 3 at this time was 1.0 MPa, and the resin pressure in Comparative Example 4 was 1.2 MPa). In addition, the resin pressure in a single screw extruder is a value shown by the gauge pressure of the resin pressure gauge provided in the intermediate dull image part of the cylinder. Thereafter, injection molding was performed in the same manner as in the above examples, and the state of structure, structural period or interparticle distance, mechanical properties, and chemical resistance were measured. The results are shown in Table 2, respectively.

  From Comparative Examples 1 and 2, when the amount of the polycarbonate alone or the vinyl cyanide monomer of the present invention was small, the chemical resistance was greatly lowered. Furthermore, when a sufficient shear cannot be applied, such as using a single screw extruder as in Comparative Examples 3 and 4, and the kneading temperature during melt kneading is too high, the desired phase structure of the present invention cannot be obtained. Therefore, the mechanical properties were low.

  The styrenic resin composition of the present invention can be used for various applications such as housings for electric / electronic parts, automobile parts, machine mechanism parts, OA equipment, home appliances, parts thereof, and miscellaneous goods.

Claims (9)

(A) (a1) 20 to 75% by weight of styrenic monomer units, (a2) 25 to 60% by weight of vinyl cyanide monomer units, and (a3) other vinyl monomers that can be copolymerized therewith A styrene resin containing 0 to 55% by weight of a monomer unit (provided that the total of (a1) to (a3) is 100% by weight), and (B) a thermoplastic resin other than the styrene resin. A styrenic resin composition having a two-phase continuous structure with a structural period of 0.001 to 1 μm or a dispersed structure with a distance between particles of 0.001 to 1 μm. The copolymerizable (a3) vinyl monomer unit containing at least one functional group selected from a carboxyl group, a hydroxyl group, an epoxy group, an amino group and an oxazoline group. The styrenic resin composition according to claim 1, comprising: The styrenic resin according to claim 1 or 2, wherein the (a1) styrenic monomer unit comprises a modified styrenic monomer unit substituted with an alkyl group having 1 to 4 carbon atoms. Composition. The styrene resin composition according to any one of claims 1 to 3, wherein the thermoplastic resin other than the (B) styrene resin is (b) a polycarbonate resin. The (b) polycarbonate resin comprises (b1) 2,2′-bis (4-hydroxyphenyl) propane and (b2) 2,2′-bis (4-hydroxy-3,5-dimethylphenyl) propane, At least one bifunctional phenolic compound selected from 2'-bis (4-hydroxy-3,5-diethylphenyl) propane and 2,2'-bis (4-hydroxy-3,5-dipropylphenyl) propane The styrenic resin composition according to claim 4, comprising an aromatic copolymer polycarbonate obtained by copolymerization of (A) (a1) 20 to 75% by weight of styrenic monomer units, (a2) 25 to 60% by weight of vinyl cyanide monomer units, and (a3) other vinyl monomers that can be copolymerized therewith Melting styrene-based resin containing 0-55 wt% of a monomer unit (however, the total of (a1) to (a3) is 100 wt%) and (B) a thermoplastic resin other than styrene-based resin The method for producing a styrene resin composition according to any one of claims 1 to 5, wherein the styrene resin composition is obtained by kneading. The manufacturing method according to claim 6, wherein the melt-kneading is performed at a resin pressure of 2.0 MPa or more. The production method according to claim 6 or 7, wherein the components are compatible under shearing during the melt kneading and phase-separated under non-shearing after discharge. A molded article obtained by melt-molding the styrenic resin composition according to any one of claims 1 to 5.