Background of the Invention Generally, compared with the atactic polystyrene which is manufactured by polymerizing the radicals, the syndiotactic polystyrene (sPS) having the stereoregularity is superior in the heat resistance, in the chemical resistance and in the electrical properties. However, the syndiotactic polystyrene is very low in the impact resistance, in the compatibility with other resins, and in the adhesion to metals, and therefore, its application has been limited.

By grafting the monomers with unsaturated radicals to the syndiotactic polystyrene, the present inventors could invent a styrenic grafted copolymer which is superior in the heat resistance, in the chemical resistance, in the compatibility with other resins, in the adhesion and in the coatability, so that the styrenic grafted copolymer can be used as a raw material of resin compositions and as a compatilizing agent. Therefore, the styrenic grafted copolymer according to the present invention and resin compositions containing it can be used to make films, sheets, packing sheets, automobile components, electric or electronic components and the like.

In order to solve the conventional problems of the conventional syndiotactic polystyrene, the random copolymerization and block copolymerization of olefin and

polar monomers were tried.

U. S. Patent 5,260,394 discloses a styrenic copolymer which consists of repeated units of substituted styrene and repeated units of olefin.

U. S. Patent 5,391,671 discloses a styrenic copolymer which consists of repeated units of substituted styrene and repeated units of acrylonitrile.

U. S. Patent 5,262,504 discloses a styrenic copolymer and its manufacturing process, which consists of repeated units of substituted styrene and repeated units of an unsaturated carboxylic acid or its ester.

U. S. Patents 5,475,061 and 5,554,695 disclose a styrenic copolymer which consists of repeated units of substituted styrene and repeated units of another structure.

However, the activity of catalyst was decreased, and the efficiency of the copolymerization was low, while if the content of comonomer was high, then the polystyrene was lead to lose the inherent properties. Thus the problems remained all the same.

In order to solve the problems of the above styrenic copolymers, a grafted copolymerization is being tried.

U. S. Patent 5,250,629 and JP 5-17533 disclose a process for manufacturing a styrenic copolymer. In this manufacturing process, a styrenic monomer having a hydrocarbon radical with an unsaturated bond is copolymerized under a catalyst system which consists of a material formed through contact between a transition metal compound and an organic aluminum compound. Then the unsaturated ethylenic monomers are graft-copolymerized, thereby manufacturing a styrenic grafted copolymer.

In the methods of the above mentioned U. S. patent and Japanese Patent, that is, in the method of grafting unsaturated ethylenic monomers to the copolymer of styrene and divinyl benzene, the unreacted vinyl radicals which remain in the copolymer of styrene and divinyl benzene are crosslinked during the grafting process, and therefore, the moldability is deteriorated fatally.

Summary of the Invention In the present invention, the styrenic polymer or copolymer without containing unsaturated hydrocarbon radicals is synthesized, and is activated by a radical initiating agent. Then it is grafted with olefin or polar monomer, thereby synthesizing a grafted copolymer. The synthesized grafted copolymer is used as a raw material for resin compositions, or used as a compatilizing agent.

Therefore it is an object of the present invention to provide a styrenic grafted copolymer in which one or more of monomers with ethylenically unsaturated bonds are grafted to a syndiotactic polystyrene.

It is another object of the present invention to provide a styrenic grafted copolymer in which diversified functional radicals are grafted to the syndiotactic polystyrene, so that the properties of the syndiotactic polystyrene can be arbitrarily controlled.

It is still another object of the present invention to provide a styrenic grafted copolymer which has no residual unreacted vinyl radicals, so that crosslinking would not occur, and that there would be no problem in the moldability.

It is still another object of the present invention to provide a styrenic grafted copolymer in which diversified functional radicals of the syndiotactic polystyrene are introduced, so that the heat resistance and the chemical resistance can be maintained intact, and that the compatibility, the adhesibility and the coatability can be improved, thereby making it possible to use it as a raw material for resin compositions, and as a compatilizer.

It is still another object of the present invention to provide a resin composition in which there are contained one or more components selected from the group consisting of a styrenic grafted copolymer, a syndiotactic polystyrene, a thermoplastic resin, a rubber, and a filler.

Brief Description of the Drawings

The above objects and other advantages of the present invention will become more apparent by describing in detail the preferred embodiment of the present invention with reference to the attache drawings in which: FIG. 1 is a SEM (scanning electron microscope) photograph showing size of the nylon particles in the syndiotactic polystyrene matrix when the content of the styrenic grafted copolymer is 0%, among the syndiotactic polystyrene/nylon/styrenic grafted copolymers; FIG. 2 is a SEM photograph showing the decrease of the size of the nylon particles in the syndiotactic polystyrene matrix when the content of the styrenic grafted copolymer is 5%, among the syndiotactic polystyrene/nylon/styrenic grafted copolymers; FIG. 3 is a SEM photograph showing the decrease of the size of the nylon particles in the syndiotactic polystyrene matrix when the content of the styrenic grafted copolymer is 10%, among the syndiotactic polystyrene/nylon/styrenic grafted copolymers; and FIG. 4 is a SEM photograph showing the decrease of the size of the nylon particles in the syndiotactic polystyrene matrix when the content of the styrenic grafted copolymer is 20%, among the syndiotactic polystyrene/nylon/styrenic grafted copolymers.

Detailed Description of the Preferred Embodiments The process for manufacturing the styrenic grafted copolymer according to the present invention includes the steps of : (1) preparing a syndiotactic stereoregular styrenic polymer having repeating units (A) by polymerizing vinylic aromatic monomers under a catalyst system, the catalyst system consisting of a transition metal compound (I) as a main catalyst component and an organic aluminum compound or an aluminoxane (II) as a cocatalyst component; and (2) graft- polymerizing monomers of Formula (B) having an unsaturated radical to the syndiotactic stereoregular styrenic polymer:

where R, is hydrogen, halogen, or a substituted radical not containing carbon-carbon double bonds but containing one or more components selected from a group consisting of : carbon, oxygen, nitrogen, sulfur, phosphorus, selenium, silicon, and tin; and m is an integer from 1 to 3 (if m is 2 or 3, Rl is same or different);

where each of R2~Rs is hydrogen, halogen, or a substituted group containing one or more components selected from the group consisting of carbon, oxygen, nitrogen, sulfur, phosphorus, selenium, silicon, and tin.

Or any two of R2~Rs are bonded together as following structure:

where rl is hydrogen, a saturated hydrocarbon of C 1-20, a hydroxy of C 1-20, a benzyl, a phenyl, or a substituted phenyl.

The styrenic grafted copolymer manufactured according to the present invention contains a polymer having the following repeating units:

where each of R"R,'and R,"is hydrogen, halogen, or a substituted group not containing carbon-carbon double bonds but containing one or more components selected from the group consisting of : carbon, oxygen, nitrogen, sulfur, phosphorus, selenium, silicon, and tin; m is an integer from 1 to 3 (if m is 2 or 3, R, is same or different); each of X, and X2 is a substituted group obtained by radical-polymerizing <BR> <BR> one or more monomers; n is an integer from 1 to 3 (in a region of 1 <n+Q<3), and is an integer from 0 to 2.

The vinylic aromatic monomer usable at the step (1) includes: styrene; alkylstyrene; halogenated styrene; vinylbiphenyl; vinylphenylnaphthalene; vinylphenylanthracene ; vinylphenylphenanthrene; vinylphenylpyrene; vinylterphenyl; vinylphenylterphenyl; vinylalkylbiphenyl; halogenated vinylbiphenyl; halogen-substituted alkylstyrene; trialkylstannylvinylbiphenyl; trialkylsilylmethylvinylbiphenyl; trialkylstannylmethylvinylbiphenyl; alkylsilylstyrene; alkyl-containing silyl styrene; halogen-containing silylstyrene; silyl-containing silyl styrene; alkoxystyrene; aminostyrene; vinylnaphthalene; vinylbenzoate and their compounds.

The preferable examples of the alkyl-styrene include: p-methylstyrene; m- methylstyrene; o-methylstyrene; 2,4-dimethylstyrene; 2,5-dimethylstyrene; 3,4- dimethylstyrene ; 3, 5-dimethylstyrene; p-ethylstyrene; m-ethylstyrene; and p- tertiarybutylstyrene.

The preferable examples of the halogenated styrene include: p-chlorostyrene; m-chlorostyrene; o-chlorostyrene; p-bromostyrene; m-bromostyrene; o- bromostyrene; p-fluorostyrene; m-fluorostyrene; o-fluorostyrene; o-methyl-p- fluorostyrene.

The preferable examples of the vinyl biphenyl include: 4-vinylbiphenyl; 3- vinylbiphenyl; and 2-vinylbiphenyl.

The preferable examples of the halogenated alkyl styrene include: p-chloro- ethylstyrene; m-chloroethylstyrene; and o-chloroethylstyrene.

The preferable example of the trialkylsilyl vinyl biphenyl includes 4-vinyl-4'- trimethyl silyl biphenyl.

The preferable example of the trialkyl stannyl vinyl biphenyl includes 4-vinyl- 4'-trimethyl stannyl vinyl biphenyl.

The preferable example of the trialkyl silyl methyl vinyl biphenyl includes 4- vinyl-4'-trimethyl silyl methyl vinyl biphenyl.

The preferable example of the trialkyl stannyl methyl vinyl biphenyl includes 4-vinyl-4'-trimethyl stannyl methyl vinyl biphenyl.

The preferable example of the alkyl silyl styrene includes p-trimethylsilyl styrene.

The preferable example of the phenyl-containing silyl styrene includes p- dimethylphenylsilylstyrene.

The preferable example of the halogen-containing silyl styrene includes p- dimethylchlorosilylstyrene.

The preferable example of the silyl-containing silyl styrene includes p- (p- trimethyl-silyl) dimethylsilylstyrene.

The preferable examples of the alkoxy styrene include: methoxy styrene, and ethoxy styrene.

The preferable example of the amino-styrene includes dimethyl-amino-styrene.

The transition metal compound (I) is expressed by formula (1) as follows: MRbR4- (a+b+e) Or M'RR3- (d+e) (1)

where M and M'are transition metals of Groups IV, V and VI of the Periodic Table, and R6~R9 are ligands bondable with metals, such as hydrogen, halogen, hydroxy, alkyl, alkoxy, cycloalkyl, acyloxy, aryloxy, cyclopentadienyl, indenyl, fluorenyl, substituted cyclopentadienyl, substituted indenyl, or substituted fluorenyl.

In the transition metal compound (I), if the ligand has two or more reaction groups which are bondable with metals, then any one of R6~R9 is bonded with one or more different metals to form multi-metal compounds of the following formulas: where M and M'are transition metals of Groups IV, V and VI of the Periodic Table; <BR> <BR> <BR> yl_y4 are selected from the group consisting of : hydrogen, halogen, hydroxy, alkyl, alkoxy, cycloalkyl, aryl, arylalkyl, alkylaryl, acyloxy, and aryloxy; Cp and Cp* are ligands bondable with metals, and are selected from the group consisting of : cyclopentadienyl, indenyl, fluorenyl, substituted cyclopentadienyl, substituted indenyl, and substituted fluorenyl; and G, G'and G"are groups for connecting two transition metals, and can be expressed by-Y-r2-Y'- [where Y and Y'are-O-,-S-, =Nr3, =Pr4- (where r3 and r4 are selected from the group consisting of : hydrogen, alkyl, cycloalkyl, alkoxy, aryl, acryl, alkylaryl, acyloxy, and aryloxy.); and r2 is one selected from the group consisting of : linear or branched alkyl, cycloalkyl,

substituted cycloalkyl, aryl, alkylaryl, and arylalkyl].

The catalyst components include: organic aluminum compounds and aluminoxane. The examples of the organic aluminum compounds include: trimethyl aluminum, triethyl aluminum, and triisobutyl aluminum. The aluminoxane is a reaction product of the organic aluminum compounds and water, and is expressed by formula (2) as follows: where Rl° is an alkyl of Cs 8, and j is an integer from 2 to 50.

In the catalyst of the step (1), the mole ratio of aluminum to the transition metal is preferably 1: 1-1 x 106: 1, and more preferably 10: 1-1 x 104: 1.

The polymerization conditions for manufacturing the syndiotactic stereoregular styrenic polymer are as follows. That is, the polymerization temperature is 0-120 degrees C; the polymerization time period is 1 second to 24 hours; the polymerization method is a bulk polymerization, a solution polymerization, or a suspension polymerization; and the usable solvent includes aliphatic hydrocarbons, and aromatic hydrocarbons.

The monomers which are grafted at the step (2) include: styrene, vinyl acetate, acrylic acid, acrylic anhydride, methacrylic acid, acrylic acid ester, methacrylic acid ester, acryl amide, acrylonitrile, maleic acid, fumaric acid, maleimide, itaconic acid, itaconic anhydride, diolefin and their derivatives. Further the grafted monomers include: maleic anhydride and a monomer selected from the group consisting of : styrene, vinyl acetate, acrylic acid, acrylic anhydride, methacrylic acid, acrylic acid ester, methacrylic acid ester, acryl amide, acrylonitrile, maleic acid, fumaric acid, maleimide, itonic acid, itaconic anhydride, diolefin and their derivatives.

The styrene derivative includes: all kinds of styrene derivatives used in the step (l).

The vinyl acetate derivative includes: vinyl-alpha- (l-cyclohexenyl) acetate.

The acrylic acid ester includes: aryl acrylate, isopropyl acrylate, ethyl acrylate, 2,3-epoxy propyl acrylate, 2-chloroethyl acrylate, chloroacrylate, cyclododesil acrylate, dibromopropyl acrylate, hydroxy ethyl acrylate, butyl acrylate, benzyl acrylate, 2-hydroxy ethyl acrylate, glycidyl acrylate, and the methacrylic acid ester derivatives corresponding to the acrylic acid ester.

The acryl amide derivative includes: N-methyl acryl amide, N-ethyl acryl amide, N-isopropyl acryl amide, N-butyl acryl amide, N-benzyl acryl amide, N-aryl acryl amide, N-phenyl acryl amide, N-methyl methacryl amide, N-ethyl methacryl amide, N-aryl methacryl amide, N- (methoxy methyl) acryl amide, N- (methoxy ethyl) acryl amide, N, N-bis (2-cianoethyl) acryl amide, N, N'-methylene bisacryl amide, 1,2- bis-acryl amide ethane, 1,5-bisacryl amide pentane, N-acryloil glycine amide, and 2- acryl amide propane sulfonic acid.

The acrylonitrile derivative includes: vinylidene cyanate, alpha-methoxy acrylonitrile, alpha-phenyl acrylonitrile, and alpha-acetoxy acrylonitrile.

The derivatives of the maleic acid, fumaric acid and maleic anhydride include: methyl maleic anhydride, phenyl maleic anhydride, chloromaleic anhydride, methyl maleic acid, phenyl maleic acid, chloromaleic acid, dimethyl malate, dibenzyl malate, diethyl fumarate, and fumaronitrile.

The maleimide derivative includes: N-butyl maleimide, N-phenyl maleimide, N-cyclohexyl maleimide, and N- (alpha-naphthyl) maleimide.

The diolefin includes: 1, 3-butadiene, isobutadiene, 1-ethoxy-1, 3-butadiene, and 1-chloro-1,3-butadiene.

Besides, unsaturated carboxylic acid, its anhydride, its ester and its amide derivatives can be used.

At the step (2), a radical initiating agent is used, and this initiating agent activates either the chain of the syndiotactic stereoregular styrenic polymer first, or the grafted monomers first, or activates the two simultaneously. In the present invention, the usable radical initiating agent includes: azo compounds, peroxide compounds or compounds capable of forming radicals.

The preferable examples of the azo compounds include: 2,2'-azobis-propane, 2,2'-dichloro-2,2'-azobis-propane, 1,1'-azo (methylethyl) diacetate, 2,2'-azobis (2- amidinopropane) nitrate, 2,2'-azobis isobutane, 2,2'-azobis isobutyl amide, 2,2'- azobis isobutyl nitrile, 2,2'-azobis-2-methyl butyl nitrile, dimethyl-2,2'-azobis isobutylate, dimethyl 2,2'-azobisisobutylate/tetrachlorotin (1/19. 53), 1, 1'-azobis (sodium-1-methyl butyl nitrile-3-sulfonate), 2- (4-methyl phenyl azo)-2-methyl malonodinitrile, 4,4'-azobis-4-cianobaleic acid, 3,5-dihydroxy methyl phenyl azo-2- aryl malonodinitrile, 2- (4-bromophenyl azo)-2-aryl malonodinitrile, 2,2'-azobis-2- propyl butyl nitrile, 1,1'-azobis cyclohexane nitrile, 2,2'-azobis-2-propyl butyl nitrile, 1, l'-azobis-l-chlorophenyl ethane, 1,1' azobis-1-cyclohexane carbonitrile, 1,1'- azobis-cycloheptane nitrile, 1, l'-azobis-l-phenyl ethane, 1,1-azobis cumene, ethyl-4- nitrophenyl azo-benzyl cianoacetate, phenyl-azo-phenyl methane, phenyl azo triphenyl methane, 4-nitrophenyl azo triphenyl methane, 1,1'-azobis-1,2-diphenyl ethane, poly (bis phenol A-4,4'-azobis-4-cianopentanoate, and poly (tetraethylene glycol-2,2'-azobis-isobutylate.

The preferable examples of the peroxide compounds include: acetyl peroxide, cumyl peroxide, tertiary butyl peroxide, propionyl peroxide, benzoyl peroxide, 2- chlorobenzoyl peroxide, 3-chlorobenzoyl peroxide, 4-chlorobenzoyl peroxide, 2,4- dichlorobenzoyl peroxide, 4-bromomethyl benzoyl peroxide, potassium persulfate, diisopropyl peroxy carbonate, tetralinhydroperoxide, l-phenyl-2-methyl propyl-1- hydroperoxide, 1-phenyl-2-methyl propyl-1-hydroperoxide, 1-phenyl-2-methyl propyl-1-hydroperoxide, tertiary butyl hydroperoxide, tertiary butyl performate, tertiary butyl peracetate, tertiary butyl perbenzoate, tertiary butyl perphenyl acetate, tertiary butyl per-4-methoxy acetate, and tertiary butyl per-N- (3-tolyl) carbamate.

The preferable examples of the compounds which are capable of forming the radicals include: 1,4-bis (penta-methylene)-2-tetrazene, 1,4-di-methoxy carbonyl- 1,4-diphenyl-2-tetrazene, and benzene sulfonyl azide.

At the step (2), the graft reaction is carried out in the following manner. That is, in accordance with the kinds of the grafting monomers and the radical polymerization initiating agent, there is carried out a solution polymerization, a

suspension polymerization or a reaction polymerization (within a reacting mixer or within an extruder), and the reaction is carried out at a temperature of 30-320 degrees C for one second to 24 hours. The solvent which can be used in the solution polymerization includes: aliphatic hydrocarbons, and aromatic hydrocarbons. The suspension polymerization is carried out in the following manner. That is, a radical initiating agent and a monomer having one or more unsaturated radicals are sufficiently diffused into a styrenic polymer, and water is used to disperse the particles so as to form a suspension, thereby carrying out a grafting copolymerization.

An organic compound and an inorganic salt are used as the suspending agent. The organic compound includes: methyl cellulose, ethyl cellulose, polyacrylic acid, polymethacrylic acid, their salts, polyvinyl alcohol, gelatine, starch, rubber, and protein. The inorganic salt includes: magnesium carbonate, calcium carbonate, calcium phosphate, titanium oxide, aluminum oxide, silicate, clay, and bentonite.

And the amount of water used is not particularly limited.

The styrenic grafted copolymer manufactured in the above described process is characterized in that the structure of the main chain has a syndiotactic stereoregularity. The syndiotactic stereoregularity is acknowledged if the following conditions are satisfied. That is, the measurements by 13CNMR should show the results that the racemic dyad within the styrenic repeated chains is 75% or more and preferably 85% or more, and the racemic pentad is 30% or more and preferably 50% or more.

Further, the average molecular weight of the main chain is generally 1,000- 3,000,000 when it is measured by GPC by dissolving it in 1,2,4-trichlorobenzene at 135 degrees C. In the grafted copolymer, the content of the grafted monomers can be different depending on the kinds of the monomers and the initiating agent. Generally, the content occupies 0.001 to 50 wt% within the total copolymer. and the reduced viscosity is 0.01 to 20 dL/g when it is measured in 1,2,4-trichlorobenzene at 135 degrees C with a concentration of 0.05 g/dL.

The grafted copolymer thus obtained is mixed with one or more ingredients selected from the group consisting of : syndiotactic polystyrene, thermoplastic resin,

rubber, and filler, so as to form various resin compositions of various applications.

The syndiotactic polystyrene which is used in the resin compositions includes: copolymers and their mixtures having the main ingredient of any one of : polystyrene, poly (alkylstyrene), poly (halogenated styrene), poly (halogenated alkyl styrene), poly (alkoxy styrene), and poly (vinyl benzoate).

The thermoplastic resin which can be used in the resin compositions includes all kinds of resins which are obtained through an add reaction or a condensation reaction. The preferable examples include: polyolefin, ethylenevinyl copolymer, amorphous polystyrene, polyester, polyacetal, polycarbonate, polyacrylate, polyamide, polyether, polyphenylene oxide, polyphenylene sulfide, polyoxy methylene, polyimide, polysulfone, polyether sulfone, polyurethane, acrylate resin, and halogenated resin. These compounds can be denatured or grafted by the styrenic monomers so as to increase the compatibility with the syndiotactic styrenic polymers.

Or they are transformed so as to have a reactive functional group or they originally have it, thereby improving the blending efficiency.

The preferable examples of the thermoplastic resins having the functional group include: polyethylene terephthalate, polybutylene terephthalate, polyoxy ethoxy benzoate and polyethylene naphthalate having one selected from the group consisting of carbonyl, hydroxy, amino, isocyanate and epoxy; polyester modified by acid; poly aryl sulfide; polyamide-6; polyamide-6,6' ; ethylene vinyl alcohol; and ethylene vinyl acetate.

The rubber which can be used in the resin compositions includes: natural rubber, polybutadiene, polyisoprene, polyisobutylene, neoprene, polysulphide rubber, acryl rubber, urethane rubber, silicon rubber, thiocol rubber, epichlorohydrine rubber, styrene/butadiene block copolymer, hydrogenated styrene/butadiene block copolymer, styrene/butadiene/styrene block terpolymer, styrene/butadiene random copolymer, ethylene/propylene copolymer, ethylene/propylene/diene copolymer, core-shelled butadiene/acrylonitrile/styrene terpolymer, methyl methacrylate/butadiene/styrene polymer, alkyl acrylate/butadiene/acrylonitrile/styrene copolymer, butadiene/styrene polymer, rubber transformed so as to have a reactive functional group, and rubber

transformed or grafted to styrenic group.

The fillers which can be used in the resin compositions have no special limitations, and include: silica, boron, alumina, titanium dioxide, magnesium oxide, aluminum hydroxide, aluminum nitride, magnesium carbonate, calcium sulfate, magnesium sulfate, potassium titanate, barium titanate, barium sulfate, talc, clay, glass fiber, boron fiber, silicon bead fiber, metal fiber, carbon black, aluminum powder, and molybdenum sulfide.

Now the present invention will be described based on actual examples. These examples are not for limiting the scope of the appended claims.

Example 1: Preparation of styrene/3 (4)-methyl styrene copolymer : A mixture of 2 L of styrene and 0.077 L of 3 (4)-methyl styrene were put into a 10L reaction vessel which had been sufficiently filled with nitrogen. Then 30 mL (0.12 moles) of TIBA was added, and then, an agitation was carried out for 15 minutes. Then 2.5 m moles of MAO was added and then an agitation was carried out for 5 minutes. Then 25 micro moles (Ti) of (Cp*Ti) 2 (OC6H4C (CH3) 2C6H40) 3 was added, and then, a pre-polymerization was carried out for one hour. Then a mixture of 10 m moles of MAO and 100 micromoles of a catalyst were added gradually over a time period of 30 minutes, and then a polymerization was carried out for one hour.

Then the reaction was terminated by putting methanol. Then a large amount of acetone was put, and NaOH was put to decompose the catalyst. Then a filtering was carried out, the methanol was washed off twice, and then a drying was carried out in a vacuum oven. The synthesized copolymer was 770 g, and the GPC measurements showed that Mn=324,000, Mwe=607,400, and MWD=1. 87. The IH NMR measurement showed a total content of 5.4 mole % of 3 (4)-methyl styrene, and a DSC measurement showed that Tg=98.6 degrees C, Tm=257.57 degrees C. The 3 (4)- methyl peak of 3 (4)-methyl styrene could be confirmed at delta 2.30,2.36 ppm of oh NMR and at delta 20.8,21.2 ppm of 13C NMR.

Preparation of (styrene/3 (4)-methyl styrene)/glycidyl methacrylate grafted copolymer: To 50 g of the styrene/3 (4)-methyl styrene copolymer which had been prepared in the above described manner, there was added 330 mL of xylene, and then an agitation was carried out for one hour, thereby sufficiently making the polymer swelled. Then a mixture which had been prepared by adding 1 g of benzoyl peroxide to 50 mL of glycidyl methacrylate was added, and then an agitation was carried out for 30 minutes. Then again, an agitation was carried out at a temperature of 110 degrees C for 6 hours. Then the reaction was made to terminate by putting methanol, and then a filtering was carried out. Then the polymer was dissolved in dichlorobenzene, and then the polymer was made to be precipitated by using methyl ethyl ketone. Then a filtering was carried out, and then a thorough wash was carried out by using methyl ethyl ketone, thereby removing the single polymers of glycidyl methacrylate. Then a drying was carried out for 5 hours in a vacuum oven. The polymer thus obtained was analyzed by NMR, and the result showed that the total content of poly glycidyl methacrylate based on the integration ratio of the peak of glycidyl radical (C (C=0) OCH7) at delta 4.464,4.092 ppm was 10.8 mole%. The GPC measurement result showed that Mn=294,600, Mw=512,400, and MWD=1.74.

Example 2 Preparation of (styrene/3 (4)-methyl styrene)/ (styrene/maleic anhydride) grafted copolymer: Instead of the glycidyl methacrylate, 10 mL of styrene and 10 g of maleic anhydride were used, and the reaction temperature was not 110 degrees C but 130 degrees C. The benzoyl peroxide was substituted by di-cumyl peroxide. Except the above matters, the manufacture was carried out in the manner same as that of Example 1. The analysis of the obtained polymer by IR showed that the C=O peak was seen at 1779.6 cm-and that the total content obtained through the optimum

curve was about 3%. The DSC measurement result showed that Tg=96.4 degrees C, and Tm=255.9 degrees C. The GPC measurement showed that Mn=266,000, Mw=463,800, and MWD=1.74.

Example 3 Preparation of (styrene/3 (4)-methyl styrene)/methyl methacrylate grafted copolymer: A mixture which had been prepared by adding 1 g of benzoyl peroxide to 50 mL of methyl methacrylate was added to 50 g of the styrene/3 (4)-methyl styrene copolymer of Example 1. Then an agitation was carried out for 30 minutes, so that the mixture would be sufficiently absorbed into the polymer. Then nitrogen was injecte into a distilled water to remove oxygen. Then 1 g of poly vinyl alcohol was added into it, and then an agitation was carried out at 200 rpm. This mixture as a suspension was agitated for 4 hours at a temperature of 95 degrees C. Then the reaction was terminated by putting methanol, a filtering was carried out, and a wash was carried out by using a sufficient amount of water, thereby removing the poly vinyl alcohol. Then this copolymer was completely dissolved in di-chloro-benzene, and it was made to be precipitated by using methyl ethyl ketone. Then a sufficient wash was carried out by using the methyl ethyl ketone, thereby removing the single copolymers of methyl methacrylate. Then a drying was carried out at a temperature of 100 degrees C for 5 hours in a vacuum oven. The copolymer thus obtained was analyzed by NMR, and the result showed that the total content of the grafted poly methyl methacrylate was 12.8 mole%. The GPC measurement showed that Mn=286,200, Mw=568,500, and MWD=1.99.

Example 4 Preparation of styrene/4-methyl styrene copolymer : Styrene and 4-methyl styrene were put in respective amounts of 2 L and

0.077 L into a 10L reaction vessel in which nitrogen had been filled. Then the manufacture was carried out in the same manner as that of the styrene/3 (4)-methyl styrene copolymer of Example 1. The amount of the synthesized copolymer was 1045 g, and the GPC measurement showed that Mn=233,900, Mw=429,200, and MWD=1.83. At'H NMR delta 2.35 ppm and at 13C NMR delta 20.8 ppm, the 4- methyl peak could be confirmed. The total content of the 4-methyl styrene was 4.5 mole%, and the DSC measurement showed that Tg=99.1 degrees C, and Tm=258.2 degrees C.

Preparation of (styrene/4-methyl styrene)/methyl methacrylate grafted copolymer : As the graft precursor, the styrene/4-methyl styrene copolymer manufactured just above was used instead of the styrene/3 (4)-methyl styrene copolymer. Except this matter, the manufacture carried out in the same manner as that of Example 3.

The'H NMR analysis on the obtained polymer showed that the total content of the grafted poly methyl methacrylate was 6.1 mole%. The IR analysis showed that the C=O peak was seen at 1730cm~1, the DSC measurement showed that Tg=99.3 degrees C, and Tm=257.4 degrees C. The GPC measurement showed that Mn=219,400, Mw=468,600, and MWD=2.14.

Example 5 Preparation of (styrene/4-methyl styrene)/ethyl acrylate grafted copolymer: Ethyl acrylate and xylene were used in amounts of 20 mL and 10 mL instead of 50 mL of the methyl methacrylate. Except this matter, the manufacture was carried out in the same manner as that of Example 4. For the obtained polymer, the 'H NMR analysis showed that the total content of the grafted poly ethyl acrylate as obtained from the integration ratio of the ethoxy (OCH2CH3) peak at delta 4.298 ppm was 10.6 mole%.

Example 6

Preparation of syndiotactic polystyrene/methyl methacrylate grafted copolymer: As the graft precursor, a styrene single polymer was used instead of the styrene/3 (4)-methyl styrene copolymer. Except this matter, the manufacture was carried out in the same manner as that of Example 3. The'H NMR analysis on the obtained polymer showed that the total content of the grafted poly methyl methacrylate was 4.7 mole%. The IR analysis showed that the C=O peak was seen at 1730cm'', and the GPC measurement showed that Mn=199,800, Mw=450,600, and MWD=2.26.

Example 7 Preparation of syndiotactic polystyrene/ethyl acrylate grafted copolymer : Ethyl acrylate and xylene were used in amounts of 20 mL and 10 mL respectively, instead of 50 mL of the methyl methacrylate. Except this matter, the manufacture was carried out in the same manner as that of Example 6. The'H NMR analysis on the obtained polymer showed that the total content of the grafted polyethyl acrylate as obtained from the integration ratio of the ethoxy (OCHCH3) peak at delta 4.281 ppm was 7.2 mole%.

Example 8 Syndiotactic polystyrene/nylon blending : Syndiotactic polystyrene and nylon in respective amounts of 36 g and 9g were mixed together. The mixing was carried out at a temperature of 280 degrees C at 50 rpm for 7 minutes by using a Haake mixer. Then a thin sheet with a thickness of 3 mm was formed by a hot pressure. This was cut under nitrogen atmosphere, and the cut edges were plated with gold. Then an observation was carried out by using an SEM (scanning electron microscope). The size of the nylon particles within the syndiotactic polystyrene matrix was 5-10 micrometers.

Example 9 Syndiotactic polystyrene/nylon/styrene grafted copolymer blending: Syndiotactic polystyrene, nylon and the (styrene/maleic anhydride) grafted copolymer of Example 2 in respective amounts of 33.75 g, 9 g, and 2.25 g were mixed together. Then the cut faces were observed in the same manner as that of Example 8. The size of the nylon particles within the syndiotactic polystyrene matrix was 2-3 micrometers.

Example 10 Syndiotactic polystyrene/nylon/styrene grafted copolymer blending : Syndiotactic polystyrene, nylon and styrene/maleic anhydride grafted copolymer of Example 2 in respective amounts of 31.5 g, 9 g, and 4.5 g were mixed together. Then the cut faces were observed in the same manner as that of Example 8.

The size of the nylon particles within the syndiotactic polystyrene matrix was less than 1 micrometer.

Example 11 Syndiotactic polystyrene/nylon/styrene grafted copolymer blending : Syndiotactic polystyrene, nylon and the (styrene/maleic anhydride) grafted copolymer of Example 2 in respective amounts of 27 g, 9 g, and 9 g were mixed together. Then the cut faces were observed in the same manner as that of Example 8.

The nylon particles within the syndiotactic polystyrene matrix could not be particularly observed.

The polymerization conditions and results for Examples 1 to 7 are shown in Tabled 1 below. The SEM photographs for the syndiotactic polystyrene/nylon/styrene

grafted copolymer blending of Examples 8 to 11 are shown in FIGs 1 to 4. It can be seen that if the content of the copolymer is increased through 0%, 5%, 10% and 20%, the size of the nylon particles within the syndiotactic polystyrene matrix is decreased.

Example 12 40g of (Styrene/4-methyl styrene)/methyl methacrylate grafted copolymer of Example 4 was carried out at a temperature of 280 degree C at 50 rpm for 5 minutes by Haake mixer. The mixture showed that the value of torque in a solid state was 30. After 1 minute, the copolymer was liquefied and the value of torque was decreased to 10 and maintained. During the reaction, it was observed that the torque was not increased and the moldability by crosslinking was not decreased.

Table 1 Example 1 2 3 4 5 6 7 Styrenic sP (S-3 (4) sP (S-3 (4) sP (S-3 (4) sP (S-4- sP (S-4- sPS sPS polymer-MS)-MS)-MS) MS) MS) Monomer GMA SM lOmL MMA MMA EA MMA EA 50mL MAH lOg 50mL 50mL 20mL 50mL 20mL Radical BPO DCP BPO BPO BPO BPO BPO initiating agent lg lg lg lg lg lg lg Solvent Xylene Xylene Water Water Water Water Water 200mL 330mL 300mL 300mL 300mL 300mL 300mL Suspension--PVA PVA PVA PVA PVA lg lg lg lg lg Temp. 110°C 130 C 95°C 95°C 95°C 95°C 95 C Time 4hr 6hr 4hr 4hr 4hr 4hr 4hr Graft 10. 8 3. 0 12. 8 6. 1 10. 6 4.7 7.2 content mole% mole% mole% mole% mole% mole% mole% IR 1730.4 1735.1 (cm-') (C=O) (MAH) (C=O) (C=O) (C=O) (C=O) (C=O) NMR 3.726 4.281 delta, ppm 4.092- (OMe) (OMe) (OCH2) (OMe) (OMe) (OCH2) DSC Tg (C) 94.3 96. 4 94. 5 99. 3 102 100 101 Tm (C) 275.1 275.6