TWI449740B - Rubber modified styrene resin and molded article produced - Google Patents

Description

Rubber modified styrene resin and molded articles obtained therefrom

The invention relates to a material suitable for preparing plastic molded articles for electrical equipment, office equipment, automobile parts, household articles, etc., in particular to a rubber modified styrene resin. The present invention also provides a molded article formed from the rubber-modified styrene resin.

Most of the components contained in plastic molded articles for electrical equipment, household goods, and the like are rubber-modified styrene resins, polycarbonate resins (Polycarbonate Resin), and the like. Among them, the rubber modified styrene resin, such as Acrylonitrile-Butadiene-Styrene Resin (ABS), has high surface hardness, good chemical resistance, good electrical properties and easy molding. Such as excellent characteristics, and gradually applied to a variety of plastic molded products.

The rubber-modified styrene-based resin can be produced by an extrusion molding method in which a rubber-modified styrene-based resin is extruded into a molten state by an extruder and then passed through a die ( Die) extrusion molding. In recent years, the application of the rubber-modified styrene-based resin to the extrusion molding method further requires an increase in the productivity thereof, and therefore, the processing properties (such as fluidity or die expansion) of the rubber-modified styrene-based resin. It is more desirable, for example, that the fluidity in the molten state is poor, the entire mold cannot be filled, the appearance and size of the molded article are not satisfactory, or the fluidity in the molten state is too good, and the mold is easily removed from the mold. The seam is leaked out, and the molded article has problems such as burrs. For example, if the die is expanded too much, the melt of the molded product may be broken, and if the surface is too small, the surface of the molded article may be rough and corrugated. In addition to the processing properties of rubber-modified styrene-based resins, it is also necessary to meet the mechanical properties required by the industry, such as impact resistance, but often improve the processing properties. It will cause poor mechanical properties, so how to strike a balance between processing properties and mechanical properties is an important topic that has been widely studied. In addition to the above problems, the current rubber-modified styrene-based resin in the process of the processing method tends to cause the mold to be stained to form a mold.

In view of the above, there is still a need to develop a rubber-modified styrene-based resin having better processing properties, and at the same time, it does not cause mold staining in subsequent processing, and the molded article formed therefrom has better heat-resistant discoloration property. And mechanical properties to meet industry needs.

Accordingly, it is a first object of the present invention to provide a rubber-modified styrenic resin which has preferred processing properties and which does not cause mold staining during processing.

Therefore, the rubber-modified styrene resin of the present invention comprises: a continuous phase formed by a copolymer of 50% by weight to 90% by weight; and a dispersed phase formed by 10% by weight to 50% by weight of rubber particles; The copolymer comprises 50% by weight to 90% by weight of a styrene monomer unit and 10% by weight to 50% by weight of a nitrileated vinyl monomer unit; the rubber particles have an occlusion structure and a non-occlusion (non-occlusion) -occlusion structure; the total content of the styrene monomer and the nitrile vinyl monomer derived from the rubber modified styrene resin accounts for the rubber modified styrene resin 100 Parts by weight below 5,000 ppm.

A second object of the present invention is to provide a molded article of a rubber-modified styrene-based resin having preferable heat-resistant discoloration properties and mechanical properties.

Then, the molded article of the rubber-modified styrene-based resin of the present invention is obtained by subjecting a rubber-modified styrene-based resin as described above to a kneading process.

The effect of the present invention is to control the content of the dimeric or trimeric body derived from the styrene monomer and the nitrile vinyl monomer in the rubber modified styrene resin to be 5,000 ppm or less, and to control The content of the copolymer and the rubber particles, and the rubber particles are designed to have a absorbing and non-occluding structure, which not only improves the processing properties of the rubber-modified styrene resin (such as MI and Die swell), but also performs extrusion molding. , it will reduce the occurrence of mold contamination during processing, and can obtain the mechanical properties (such as impact resistance, SP, Tsy and EL) and better heat-resistant discoloration of the rubber modified styrene resin itself. Sexual molded products.

The rubber-modified styrene-based resin of the present invention comprises: a continuous phase formed by a copolymer of 50% by weight to 90% by weight; and a dispersed phase formed by 10% by weight to 50% by weight of rubber particles, wherein the copolymer comprises 50% by weight to 90% by weight of the styrene monomer unit and 10% by weight to 50% by weight of the nitrile vinyl monomer unit; the rubber particles have a absorbing structure and a non-occluding structure; the rubber modified styrene The total content of the dimeric or trimeric body derived from the styrene monomer and the nitrile vinyl monomer in the resin is 5,000 ppm or less based on 100 parts by weight of the rubber-modified styrene resin.

Preferably, the total content of the styrene monomer and the nitrile vinyl monomer derived from the rubber-modified styrene resin is 100 parts by weight of the rubber-modified styrene resin. From 1,000 ppm to 4,000 ppm. More preferably, the total content of the styrene monomer and the nitrile vinyl monomer derived from the rubber-modified styrene resin is 100 parts by weight of the rubber-modified styrene resin. 1,200 ppm to 3,500 ppm.

Preferably, the continuous phase is formed from 60% by weight to 89% by weight of the copolymer, and the dispersed phase is formed from 11% by weight to 40% by weight of rubber particles. More preferably, the continuous phase is formed from 70% by weight to 88% by weight of the copolymer, and the dispersed phase is formed from 12% by weight to 30% by weight of rubber particles.

The rubber modified styrene resin is produced by emulsifying a polymerized rubber graft copolymer (I), a bulk or solution polymerized rubber graft copolymer (II), and a suspension polymerized ethylene copolymer (III). It is made by the way of mixing. Preferably, the rubber-modified styrene-based resin is composed of 1% by weight to 25% by weight of an emulsion polymerized rubber graft copolymer, and 20% by weight to 90% by weight of a block or solution polymerized rubber graft copolymer, and 9 to 55% by weight of the suspension-polymerized ethylene-based copolymer was obtained by kneading.

The rubber particles in the rubber-modified styrene-based resin obtained include rubber particles having a absorbing structure and rubber particles having a non-occlusive structure; and the rubber particles having the absorbing structure are formed of rubber components. The shell and the core formed by the copolymer, and the rubber particles having a non-occluded structure are formed of a rubber component. The rubber component is a rubber component used in a bulk or solution-polymerized rubber graft copolymer (II).

Hereinafter, the emulsion rubber graft copolymer (I), the bulk or solution polymer rubber graft copolymer (II), and the suspension polymerized ethylene copolymer (III) will be described in detail:

<suspended polymerized ethylene copolymer (III)>

The suspension-polymerized ethylene-based copolymer (III) comprises a styrene-based monomer (i-1) and a nitrile-vinyl monomer (i-2), and optionally other copolymerizable vinyl monomers. The first component of (i-3) is obtained by suspension polymerization.

The styrene monomer (i-1) may be used singly or in combination, and the styrene monomer (i-1) includes, but is not limited to, styrene, α-methylstyrene, p-tert-butylbenzene. Ethylene, p-methylstyrene, o-methylstyrene, m-methylstyrene, 2,4-dimethylstyrene, ethylstyrene, α-methyl-p-methylstyrene and Bromostyrene and the like. Preferably, the styrenic monomer (i-1) is selected from the group consisting of styrene, α-methylstyrene, or the like. Preferably, the content of the styrene monomer (i-1) is 50% by weight based on 100% by weight of the total of (i-1), (i-2), and (i-3). 90% by weight; more preferably, 55% by weight to 85% by weight; still more preferably, 58% by weight to 80% by weight.

The nitridinated vinyl monomer (i-2) may be used singly or in combination, and the nitrileated vinyl monomer (i-2) includes, but not limited to, acrylonitrile, α-methacrylonitrile, and the like. Preferably, the nitrileated vinyl monomer (i-2) is acrylonitrile. Preferably, the content of the nitridinated vinyl monomer (i-2) is 10% by weight based on 100% by weight of the total of (i-1), (i-2), (i-3) ～50% by weight; more preferably, 15% by weight to 45% by weight; still more preferably 20% by weight to 42% by weight.

The other copolymerizable vinyl monomer (i-3) may be used singly or in combination, and the other copolymerizable vinyl monomer (i-3) includes, but is not limited to, an acrylic monomer, a methacrylic acid system. Monomer, acrylate monomer, methacrylate monomer, monofunctional maleimide monomer, ethylene, propylene, 1-butene, 1-pentene, 4-methyl-1- Pentene, vinyl chloride, vinylidene chloride, tetrafluoroethylene, chlorotrifluoroethylene, butadiene, propenylamine, isobutenylamine, vinyl acetate, Ethyl vinyl ether, methyl vinyl ketone, triallyl isocyanate, anhydrous maleic acid, anhydrous methyl maleic acid ( Cis-methylbutenedioic acid), trans-methylbutenedioic acid, fumaric acid, itaconic acid, dimethylfumarate, itaconic acid Dibutyl itaconate and the like. Preferably, the content of the other copolymerizable vinyl monomer (i-3) is in the range of 100% by weight based on the total amount of (i-1), (i-2), (i-3) 0% by weight to 40% by weight; more preferably 1% by weight to 34% by weight; still more preferably 3 to 30% by weight.

The acrylic monomer includes, but is not limited to, acrylic acid or the like. The methacrylic monomer includes, but is not limited to, methacrylic acid or the like. The acrylate monomer includes, but is not limited to, methyl acrylate, ethyl acrylate, isopropyl acrylate, butyl acrylate, and the like. Preferably, the acrylate monomer is butyl acrylate.

The methacrylate monomer includes, but is not limited to, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, benzyl methacrylate, hexyl methacrylate, and Cyclohexyl acrylate, dodecyl methacrylate, 2-hydroxyethyl methacrylate, glycidyl methacrylate, dimethylaminoethyl methacrylate, ethylene glycol Ethylene dimethacrylate, neopentyl dimethacrylate, and the like. Preferably, the methacrylate monomer is selected from methyl methacrylate or butyl methacrylate.

In the suspension polymerization, a suspension stabilizer may be optionally added. The suspension stabilizer may be used singly or in combination, and the suspension stabilizer includes, but is not limited to, (1) inorganic suspension stabilizer: clay, barium sulfate, magnesium hydroxide, etc.; (2) organic suspension stabilizer: polyvinyl alcohol (polyvinylalcohol, abbreviated as PVA), carboxymethylcellulose (CMC), polyacrylamide, and the like. Preferably, the suspension stabilizer is contained in an amount ranging from 1 ppm to 100 ppm based on 100 parts by weight of the total of (i-1), (i-2), and (i-3).

In the suspension polymerization, a salting-out agent may be optionally added. The salting-out agent may be used singly or in combination, and the salting-out agent includes, but not limited to, sodium sulfate, potassium sulfate, sodium hydrogen sulfite, potassium hydrogen sulfite, ammonium hydrogen sulfite, pyrosulfite, pyrosulfate, and Hydrosulfite, formaldehydesulfoxylate, thiosulfate, sulfoxylate. Preferably, the salting-out agent is selected from the group consisting of sodium hydrogen sulfite, sodium metabisulfite, sodium dithionite or sodium formaldehyde sulfoxylate. Preferably, the salting-out agent is contained in an amount ranging from 10 ppm to 1,000 ppm based on 100 parts by weight of the total of (i-1), (i-2), and (i-3).

In the suspension polymerization, water may be selectively added. Preferably, the content of the water is from 0.5 to 10 times the total amount of the monomers, based on 100 parts by weight of the total of (i-1), (i-2), and (i-3).

In the suspension polymerization, a polymerization initiator may be optionally added. The polymerization initiator is selected from a monofunctional polymerization initiator, a polyfunctional polymerization initiator, or a combination thereof. The monofunctional polymerization initiator may be used singly or in combination, and the monofunctional polymerization initiator includes, but is not limited to, benzoyl peroxide, dicumyl peroxide, T-butyl peroxide, t-butyl hydroperoxide, cumene hydroperoxide, t-butyl peroxybenzoate T-butyl-peroxy benzoate), bis-2-ethylhexyl peroxy dicarbonate, tert-butyl peroxy isopropyl carbonate BPIC), cyclohexanone peroxide, 2,2'-azo-bis-isobutyronitrile (AIBN), 1,1'-azobicyclo 1,1'-azo-biscyclohexane-1-carbonitrile, 2,2'-azo-bis-2-methylbutyronitrile (2,2'-azo-bis-2- Methyl butyronitrile) and the like. Among them, benzammonium peroxide and 2,2'-azo-bis-isobutyronitrile are preferred.

The polyfunctional polymerization initiator may be used singly or in combination, and the polyfunctional polymerization initiator includes, but is not limited to, 1,1-bis-tert-butylperoxycyclohexane (1,1-bis-t) -butyl peroxy cyclohexane (TX-22), 1,1-bis-tert-butylperoxide-3,3,5-trimethylcyclohexane (1,1-bis-t-butylperoxy-3,3 ,5-trimethyl cyclohexane, abbreviated as TX-29A), 2,5-dimethyl-2,5-bis-(2-ethylperoxyhexane)hexane [2,5-dimethyl-2,5-bis -(2-ethylhexanoxy peroxy)hexane], 4-(t-butylperoxycarbonyl)-3-hexyl-6-[7-(t-butylperoxycarbonyl)heptyl]cyclohexane {4-( T-butyl peroxy carbonyl)-3-hexyl-6-[7-(t-butyl peroxy carbonyl)heptyl] cyclohexane}, di-t-butyl-diperoxyazelate , 2,5-Dimethyl-2,5-bis(benzoquinone peroxy)hexane, 2,5-dimethyl-2,5-bis-(benzoyl peroxy)hexane, di-t-butyl Di-t-butyl peroxy-hexahydro-terephthalate (BPHTH), 2,2-bis(4,4-di-t-butylperoxy)cyclohexylpropane [ 2,2-bis-(4,4-di-t-butyl peroxy)cyclohexyl propane, abbreviated as P X-12] and so on.

In the suspension polymerization, a chain transfer agent may be selectively added. The chain transfer agent may be used singly or in combination, and the chain transfer agent includes, but is not limited to, n-dodecyl mercaptan (NDM), stearyl mercaptan, and third. - T-dodecyl mercaptan (TDM), n-propyl mercaptan, n-octyl mercaptan, tri-octyl mercaptan, tri-decyl mercaptan, and the like.

Preferably, the suspension polymerization reaction has an operating temperature in the range of from 30 ° C to 160 ° C; more preferably, the suspension polymerization has an operating temperature in the range of from 50 ° C to 120 ° C. Preferably, the suspension-polymerized ethylene-based copolymer (III) has a weight average molecular weight in the range of 180,000 or more.

[Bulk or solution polymerized rubber graft copolymer (II)]

The block or solution polymerized rubber graft copolymer (II) is obtained by bulk or solution polymerization of a second component, wherein the second component comprises 50% by weight to 90% by weight of a styrene system. a monomer and 10% by weight to 50% by weight of a nitrileated vinyl monomer, and optionally 0% to 40% by weight of other copolymerizable vinyl monomer, and the total amount of the above monomers is 0.5 parts by weight to 25 parts by weight of the rubber component, based on 100 parts by weight. In the bulk or solution polymerization, an additive may be optionally added, and the additive includes, but is not limited to, a solvent, a polymerization initiator or a chain transfer agent, and the like.

Preferably, the rubber component is selected from a diene rubber, a polyacrylate rubber, or a polyoxyalkylene rubber.

Preferably, the diene rubber is obtained by polymerizing a diene monomer, and has a glass transition temperature of 0 ° C or lower. The diene rubber includes, but is not limited to, butadiene rubber, isoprene rubber, chloroprene rubber, ethylene propylene diene terpolymer (EPDM), styrene. - a diene rubber, an acrylonitrile-diene rubber, or the like. Wherein, the butadiene rubber comprises, but is not limited to, a high cis (Hi-Cis) content of butadiene rubber and a low cis (Low-Cis) content of butadiene rubber. The typical weight composition of cis (Cis)/vinyl (Vinyl) in the high cis content butadiene rubber is (94 to 99 wt%) / (0 to 5 wt%), and the rest of the composition is trans. (Trans) structure, and Mooney viscosity is between 20 and 120, and the molecular weight range is preferably from 100,000 to 800,000. The typical weight composition of cis/vinyl in the low cis content butadiene rubber ranges from (20 to 40 wt%) / (6 to 20 wt%), the balance is trans structure, and the Mooney viscosity is From 20 to 120, the molecular weight range is preferably from 100,000 to 800,000. The styrene-diene rubber includes, but is not limited to, styrene-butadiene rubber, styrene-isoprene rubber, and the like, and the styrene-diene rubber may be a block copolymer or a random copolymer. Or a composition in which the composition is tapered/tapered, wherein the styrene-butadiene rubber preferably has a weight ratio of styrene of 50% by weight or less, and preferably has a molecular weight of 50,000 to 600,000. Preferably, the styrene-diene rubber is a styrene-butadiene rubber.

The styrene monomer, the nitrile vinyl monomer, the other copolymerizable vinyl monomer, the polymerization initiator, and the chain transfer agent are as described above in the preparation of the styrene in the suspension polymerization ethylene copolymer (III). The type of monomer (i-1), nitrileated vinyl monomer (i-2), other copolymerizable vinyl monomer (i-3), polymerization initiator and chain transfer agent, so it is no longer Narration.

The solvent may be used singly or in combination, and the solvent includes, but is not limited to, benzene, toluene, ethylbenzene, p-xylene, o-xylene, m-xylene, pentane, octane, cyclohexane, methyl ethyl ketone, acetone, and methyl ketone. Ketone, or a combination of these. Preferably, the content of the solvent is in the range of 0 parts by weight based on 100 parts by weight of the total of the rubber component, the styrene monomer, the nitrileated vinyl monomer, and the other copolymerizable vinyl monomer. 100 parts by weight; more preferably, the solvent is contained in an amount ranging from 0 part by weight to 60 parts by weight; more preferably, the solvent is contained in an amount ranging from 1 part by weight to 50 parts by weight.

Preferably, the content of the polymerization initiator is in the range of 100 parts by weight based on 100 parts by weight of the total of the rubber component, the styrene monomer, the nitrile vinyl monomer, and the other copolymerizable vinyl monomer. The parts by weight to 1 part by weight; more preferably, the polymerization initiator is contained in an amount ranging from 0.001 part by weight to 0.5 part by weight.

Preferably, the chain transfer agent is present in an amount ranging from 0 parts by weight based on 100 parts by weight of the total of the rubber component, the styrenic monomer, the nitrileated vinyl monomer, and the other copolymerizable vinyl monomer. Parts to 2 parts by weight; more preferably, the chain transfer agent is contained in an amount ranging from 0.001 part by weight to 1 part by weight.

The bulk or solution polymerized rubber graft copolymer (II) is prepared by using the above rubber component, styrene monomer, nitrile vinyl monomer, and other copolymerizable vinyl monomer. Continuously fed into the reactor, after the reaction reaches the desired conversion rate, the solution after the reaction is continuously taken out from the reaction device, and introduced into a devolatilizer, by which the unreacted start is The bulk or solution-polymerized rubber graft copolymer (II) of the present invention can be obtained by removing the raw material and the volatile component produced after the reaction, or further granulating. The final monomer conversion rate in the general polymerization reaction is 50% by weight or more, preferably 60% by weight or more, and more preferably 70% by weight or more. In general, the devolatilizer can use a vacuum degassing tank device or a degasser. The unreacted starting material or volatile component removed by the devolatilizer is optionally recovered by a condenser, and if necessary, the water in the recovered liquid can be removed and used as a starting material.

The reactor includes, but is not limited to, a plug flow reactor (PFR), a continuous stirred-tank reactor (CSTR), or a reactor containing a static mixer (Static reactor) )Wait. The number of the reactors may be one, or two or more, preferably three or more, in combination. When more than two reactors are used, the first reactor is preferably a fully mixed reactor (CSTR), and the final reactor is preferably a columnar flow reactor (PFR).

Preferably, the operating temperature of the reactor ranges from 20 ° C to 300 ° C; more preferably, the operating temperature of the reactor ranges from 60 ° C to 250 ° C; more preferably, the operating temperature range of the reactor is 80 °C ~ 240 °C. Preferably, the operating pressure of the reactor ranges from 1 kg/cm ² to 10 kg/cm ² .

[Emulsified Polymer Rubber Graft Copolymer (I)]

The emulsion-polymerized rubber graft copolymer (I) is a third component comprising 40% by weight to 90% by weight of a rubber emulsion (solid content) and 10% by weight to 60% by weight of a functional monomer component. The polymerization reaction is carried out, wherein the functional monomer component comprises 50% by weight to 90% by weight of a styrene monomer, 10% by weight to 50% by weight of a nitrile vinyl monomer, and 0% by weight to ～ 40% by weight of other copolymerizable vinyl monomers. In the emulsion polymerization reaction, an additive may be optionally added, and the additive includes, but is not limited to, an emulsifier, a polymerization initiator or a chain transfer agent, and the like. After the emulsion polymerization reaction, it can be selectively subjected to steps such as coagulation, dehydration, and drying.

The rubber emulsion is obtained by emulsion polymerization of the rubber component, or further subjected to hypertrophy treatment after the emulsion polymerization reaction, and optionally adding other copolymerizable monomers to the emulsion polymerization reaction. The rubber component is the rubber component of the above-mentioned bulk or solution polymerized rubber graft copolymer (II). The other copolymerizable monomers include, but are not limited to, styrene, acrylonitrile, (meth) acrylate, and the like.

The hypertrophy treatment can be carried out by a general method of freezing fat, mechanical fat or additive hypertrophy. The additives used in the additive hypertrophy method include, but are not limited to, (1) acidic substances: acetic anhydride, hydrogen chloride, sulfuric acid, etc.; (2) salt-based substances: sodium chloride, potassium chloride, calcium chloride, etc.; A polymer aggregating agent containing a carboxylic acid group: a (meth)acrylic acid-(meth)acrylate copolymer (such as a methacrylic acid-butyl acrylate copolymer, a methacrylic acid-ethyl acrylate copolymer) or the like.

For example, the method for producing a diene rubber emulsion can be polymerized by an emulsion polymerization method using a diene monomer (for example, butadiene), or 50% by weight to 100% by weight of a diene monomer and 0% by weight. The monomer such as styrene and/or acrylonitrile of 50% by weight is polymerized by an emulsion polymerization method to obtain a diene rubber emulsion having a weight average particle diameter of 0.05 μm to 0.6 μm. A small particle size diene rubber emulsion having a weight average particle diameter of 0.05 μm to 0.20 μm may be obtained by an emulsion polymerization method, and then subjected to a fertilizer treatment to increase the weight of the small particle size diene rubber emulsion. A large particle size diene rubber emulsion having an average particle diameter of 0.22 μm to 0.6 μm.

The styrene monomer, the nitrile vinyl monomer, the other copolymerizable vinyl monomer, the polymerization initiator, and the chain transfer agent in the functional monomer component are prepared as described above for the suspension polymerization ethylene copolymerization. Styrene monomer (i-1), nitrile vinyl monomer (i-2), other copolymerizable vinyl monomer (i-3), polymerization initiator and chain in the compound (III) The type of transfer agent is not described here.

In the process of preparing the rubber-modified styrene-based resin of the present invention, various additives may be added as necessary, and the additive is selected from the group consisting of an antioxidant, a plasticizer, a processing aid, an ultraviolet stabilizer, an ultraviolet absorber, a filler, A reinforcing agent, a coloring agent, a slip agent, a charging inhibitor, a flame retardant, a flame retardant, a heat stabilizer, a coupling agent, or a combination thereof. The above additives may be respectively polymerized in the polymerization reaction of the above-mentioned emulsion polymerization rubber graft copolymer (I), bulk or solution polymerization rubber graft copolymer (II) or suspension polymerization ethylene copolymer (III), after polymerization, condensation The above or the above additives may be added during the process of preparing the rubber-modified styrene resin by performing the extrusion kneading treatment. Preferably, the additive is contained in an amount ranging from 0.1 part by weight to 5 parts by weight based on 100 parts by total of the total amount of the rubber-modified styrene-based resin.

The processing aid may be used singly or in combination, and the processing aid includes, but is not limited to, a high molecular weight styrene-acrylonitrile copolymer (having a molecular weight of 2,000,000 or more) or an acrylic copolymer. Preferably, the content of the high molecular weight acryl copolymer is 5 parts by weight or less based on 100 parts by weight of the total amount of the rubber-modified styrene resin.

The antioxidant may be used singly or in combination, and the antioxidant includes, but is not limited to, a phenol-based antioxidant, a thioether-based antioxidant, a phosphorus-based antioxidant, and the like. Preferably, the antioxidant is contained in an amount of 2 parts by weight or less based on 100 parts by weight of the total of the rubber-modified styrene resin.

The phenolic antioxidant may be used singly or in combination, and the phenolic antioxidant includes, but is not limited to, octadecyl 3,5-bis(1,1-dimethylethyl)-4-hydroxyphenylpropionate. [3,5-bis(1,1-dimethylethyl)-4-hydroxybenzenepropanoic acid octadecyl ester, model: antioxidant IX-1076], triethylene glycol bis[3-(3-tert-butyl-5-methyl) 4-hydroxyphenyl)propionate], tetrakis[methylene-3-(3,5-bis-tert-butyl-4-hydroxyphenyl)propionate]methane, 2-tert-butyl- 6-(3-Tertibutyl-2-hydroxy-6-methylbenzyl)-4-methylphenyl acrylate, 2,2'-methylene-bis(4-methyl-6- Third butyl phenol) [2,2'-methylenebis (4-methyl-6-tert-butylphenol), model: antioxidant 2246], 2,2'-thiobis(4-methyl-6-third butyl Phenol), 2,2'-thio-diethylene-bis[3-(3,5-bis-tert-butyl-4-hydroxyphenyl)propionate], 2,2'-ethane Indoleamine-bis[ethyl-3-(3,5-bis-tert-butyl-4-hydroxyphenyl)propionate].

The thioether-based antioxidant may be used singly or in combination, and the thioether-based antioxidant includes, but is not limited to, distearyl thiodipropionate, dipalmitole thiodipropionate, pentaerythritol-tetra-( --dodecyl-thiopropionate, dioctadecyl sulfide, and the like.

The phosphorus-based antioxidant may be used singly or in combination, and the phosphorus-based antioxidant is selected from a phosphite-containing phosphorus-based antioxidant or a phosphate-containing phosphorus-based antioxidant. The phosphite-containing phosphorus-based antioxidant includes, but is not limited to, tris(nonylphenyl) phosphite, dodecyl phosphite, 4,4'-butylene bis(3-methyl-6- Tributylphenyl-bistridecylphosphite), tris(2,4-t-butylphenyl)phosphite, and the like. The phosphate-containing phosphorus-based antioxidant includes, but is not limited to, tetrakis(2,4-t-butylphenyl)-4,4'-extended biphenyl phosphate, 9,10-dihydro-9-oxy- 10-phosphate phenoxy-10-oxygen and the like.

The slip agent may be used singly or in combination, and the slip agent includes, but is not limited to, metal soap such as calcium stearate, magnesium stearate, lithium stearate, and ethylene bis-stearamide. EBA), methylene distearylamine, palmitate, butyl stearate, palmitate stearate, polypropionate tristearate, n-docosanoic acid, stearic acid, etc. , polyethylene wax, octadecanoic acid wax, carnuba wax, petroleum wax and the like. Preferably, the content of the slip agent is in the range of 2 parts by weight or less based on 100 parts by weight of the total of the copolymer and the rubber particles.

The filler may be used singly or in combination, and the filler includes, but is not limited to, calcium carbonate, alumina, mica, and the like. The enhancer may be used singly or in combination, and the reinforcing agent includes, but is not limited to, glass fibers, carbon fibers, various whiskers, and the like.

In the process of preparing the rubber-modified styrene-based resin of the present invention, various polymers may be mixed as necessary. The polymer may be used singly or in combination, and the polymer includes, but is not limited to, acrylonitrile-butadiene-α-methylstyrene resin, acrylonitrile-styrene-methyl methacrylate resin, acrylonitrile-styrene -nitro-phenylmaleimide resin, styrene-anhydrous maleic acid resin, styrene-nitrogen-phenyl maleimide resin, polymethyl methacrylate, polycarbonate resin, styrene - Methacrylic resin, methacrylic acid-butadiene-styrene resin, acrylonitrile-butadiene-nitrogen-phenylmaleimide-styrene resin, polyamide resin, polyester resin, polyphenylene ether Resin, acrylonitrile-acrylate rubber-styrene resin, acrylonitrile-(ethylene-propylene diene rubber)-styrene resin, acrylonitrile-ruthenium-styrene resin, and other resins. The content of the polymer is 80 parts by weight or less based on 100 parts by weight of the total amount of the rubber-modified styrene resin.

The preparation method of the rubber modified styrene resin can be carried out by a general mixing method, and the mixture is placed in a stirrer to be stirred, uniformly mixed, and if necessary, an additive or a polymer can be added to obtain the rubber modified styrene of the present invention. Resin.

The molded article of the rubber-modified styrene-based resin of the present invention is obtained by subjecting a rubber-modified styrene-based resin as described above to a kneading process. The kneading processing and molding process can be carried out in a conventional manner, and therefore will not be described again.

The invention is further described in the following examples, but it should be understood that these examples are for illustrative purposes only and are not to be construed as limiting.

<Example>

[Synthesis Example 1] Emulsion Polymerized Rubber Graft Copolymer (I)

95.0 parts by weight of 1,3-butadiene, 5.0 parts by weight of acrylonitrile, 15.0 parts by weight of potassium persulfate solution, 3.0 parts by weight of sodium pyrophosphate, 1.5 parts by weight of potassium oleate, and 140.0 parts by weight of distilled water And 0.2 part by weight of the third-dodecyl mercaptan was reacted at a reaction temperature of 65 ° C for 12 hours to obtain a rubber emulsion having a conversion of 94%, a solid content of about 40% and a weight average particle diameter of 0.1 μm.

85.0 parts by weight of ethyl acrylate, 15.0 parts by weight of acrylic acid, 0.3 parts by weight of thirteen-dodecyl mercaptan, 2.0 parts by weight of potassium oleate, 1.0 part by weight of sodium dioctylsulfosuccinate, 0.4 The parts by weight of isopropylbenzene hydrogen peroxide, 0.3 parts by weight of sodium formaldehyde sulfoxylate and 200.0 parts by weight of distilled water are reacted at a reaction temperature of 75 ° C for 5 hours to obtain a conversion of 95% and a pH of 6.0. A polymer aggregating agent containing a carboxylic acid group.

Next, 3 parts by weight of the above-mentioned carboxylic acid group-containing polymer flocculant (dry weight) is used to ferment 100 parts by weight of the above rubber emulsion (dry weight), and the obtained enlarged rubber emulsion has a pH of 8.5 and an average weight of particles. The diameter is 0.30 μm. Thereafter, 100.0 parts by weight of the above-mentioned enlarged rubber emulsion (dry weight), 25.0 parts by weight of styrene, 8.3 parts by weight of acrylonitrile, 1.2 parts by weight of potassium oleate, and 0.2 parts by weight of a third-dodecyl group Mercaptan, 0.5 parts by weight of cumene hydroperoxide, 3.0 parts by weight of ferrous sulfate solution (concentration: 0.2 wt%), 3.0 parts by weight of sodium formaldehyde sulfoxylate solution (concentration: 10 wt%), 20.0 parts by weight Ethylenediamine tetraacetic acid solution (concentration: 0.25 wt%) and 200.0 parts by weight of distilled water are mixed and reacted, wherein the styrene and acrylonitrile are added to the reaction system for polymerization within 5 hours by continuous addition, followed by chlorine After the calcium (CaCl ₂ ) is coagulated, dehydrated, and then dried to a moisture content of 2% or less, the emulsion polymerized rubber graft copolymer (I) required by the present invention can be obtained, and the rubber component content is 75% by weight. And the weight average particle diameter of the rubber particles was 0.31 μm.

[Synthesis Example 2] Bulk or solution polymerization rubber graft copolymer (II)

103.2 parts by weight of styrene, 15 parts by weight of styrene/butadiene rubber (styrene/butadiene content = 25% by weight / 75% by weight, Mw = 130,000), 45.4 parts by weight of ethylbenzene, 31.4 Parts by weight of acrylonitrile, 3.9 parts by weight of butyl acrylate, 0.08 parts by weight of n-dodecyl mercaptan, 0.063 parts by weight of 3,5-bis(1,1-dimethylethyl)-4- Octadecyl hydroxyphenylpropionate and 0.063 parts by weight of ethylenedistearylamine were mixed to form a mixture.

100 parts by weight of styrene, 3.0 parts by weight of 1,1-bis-tert-butylperoxycyclohexane, and 1.8 parts by weight of diphenylguanidinium peroxide were used to form a polymerization initiator solution.

The above mixture was pumped at a flow rate of 61 kg/hour, and the above polymerization initiator solution was continuously supplied to the first reactor at a flow rate of 1.3 kg/hour to carry out a reaction, and the polymer solution after the reaction was further reacted. The reaction proceeds to the second reactor, the third reactor, and the fourth reactor. The first, second, third, and fourth reactors are sequentially connected in series, and the reactors are all columnar flow reactors having a capacity of 100 liters. The first reactor reaction temperature is 75 ° C ~ 90 ° C, stirring at 110 rpm, the second reactor reaction temperature is 95 ~ 105 ° C, stirring at 80 rpm, the third reactor reaction temperature 110 ~ 125 ° C, at 60 rpm After stirring, the fourth reactor was reacted at a temperature of 135 to 150 ° C, and stirred at a rotation speed of 5 rpm, and finally the polymer solid content was 62.5%. After the reaction is completed, the unreacted monomer and solvent are removed by a devolatilization device for recycling, and then the strip is extruded through a die, and then cooled or pelletized to obtain a block or solution polymerized rubber graft copolymer. (II).

[Synthesis Example 3] Thermally polymerized ethylene copolymer

60 wt% of styrene and 40 wt% of acrylonitrile were placed at a rate of 12 kg/hr in a fully mixed reactor equipped with a stirrer maintained at 150 ° C and a capacity of 45 liters. And reacting, further adding ethylene distearylamine and tert-dodecyl mercaptan to the reaction at a rate of 3.0 g / hr, after the reaction, a reaction liquid having a solid content of 55% can be obtained, After the reaction liquid was removed by a devolatilization apparatus, particles of a thermally polymerizable ethylene-based copolymer having an acrylonitrile content of 28% by weight were obtained.

While obtaining the particles of the thermally polymerized ethylene-based copolymer, the removed volatile components can be condensed by a condenser as a recovery liquid, and continuously added to the reaction for reuse.

[Synthesis Example 4] Suspension polymerization of ethylene-based copolymer (III)

70% by weight of styrene monomer, 30% by weight of nitrileated vinyl monomer, and the amount of 2,2'-azo-bis-isobutyronitrile used is 40% by weight based on 100 parts by weight of all monomers. Ppm, and the amount of the third-dodecyl mercaptan used was 15 ppm mixed uniformly to form the first component.

100 parts by weight of 10 ppm of polyvinyl alcohol, 100 ppm of sodium sulfate, and 1.5 times of ion-exchanged water were uniformly mixed with respect to 100 parts by weight of all monomers to form a second component. The first component and the second component were poured into a 50 liter reactor equipped with a stirrer and stirred for 15 minutes. The temperature in the reactor was raised to 70 ° C, and the reaction was taken for 4 hours, and the copolymer was separated, washed, and dried. The final polymerization rate was 95%, and a suspension-polymerized ethylene-based copolymer (III) having a weight average molecular weight of 250,000 was obtained.

[Example 1] Rubber-modified styrene-based resin and molded article thereof

The emulsion-polymerized rubber graft copolymer (I) of Synthesis Example 1, the bulk or solution rubber graft copolymer (II) of Synthesis Example 2, and the suspension-polymerized ethylene copolymer (III) of Synthesis Example 4, High molecular weight acrylic copolymer (Mitsubishi Rayon, model METABLEN P-530A), octadecyl 3,5-bis(1,1-dimethylethyl)-4-hydroxyphenylpropionate (Ciba company, model IX-1076) and ethylene distearamine (made by Nippon Oil Co., Ltd., EBA for short), you can get rubber modified styrene resin, followed by Werner & Pfleidrer ZSK 35 extruder The mixture was kneaded at 220 ° C to obtain a molded article of a rubber-modified styrene resin. The analysis and physical property evaluation results are shown in Table 1.

[Examples 2 to 4]

In Examples 2 to 4, the rubber-modified styrene-based resin and the molded article thereof were prepared in the same manner as in Example 1, except that the emulsion polymerized rubber graft copolymer (I), block or solution was changed. Rubber graft copolymer (II), suspension polymerized ethylene copolymer (III), high molecular weight acrylic copolymer, 3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl The amounts of octadecyl propionate and ethylene distearamide were analyzed and the results of physical property evaluation are shown in Table 1.

[Comparative Example 1] Rubber-modified styrene-based resin and molded article thereof

The emulsion-polymerized rubber graft copolymer (I) of Synthesis Example 1, the bulk or solution rubber graft copolymer (II) of Synthesis Example 2, the thermally polymerized ethylene-based copolymer of Synthesis Example 3, and the high molecular weight pressure according to Table 2; The rubber copolymer, the octadecyl 3,5-bis(1,1-dimethylethyl)-4-hydroxyphenylpropionate and the ethylene distearylamine can be mixed to obtain the rubber modification. The styrene-based resin was mixed with a Werner & Pfleidrer ZSK 35 extruder at 220 ° C to obtain a molded article of a rubber-modified styrene-based resin. The analysis and physical property evaluation results are shown in Table 2.

[Comparative Examples 2 to 5]

In Comparative Examples 2 to 5, the rubber-modified styrene-based resin and its molded article were prepared in the same manner as in Comparative Example 1, except that the emulsion polymerized rubber graft copolymer (I), block or solution was changed. Rubber graft copolymer (II), suspension polymerized ethylene copolymer (III), thermally polymerized ethylene copolymer, high molecular weight acrylic copolymer, 3,5-bis(1,1-dimethylethyl The use amount of octadecyl-4-hydroxyphenylpropionate and ethylenedistearylamine was analyzed and the results of physical property evaluation are shown in Table 2.

【Test items】

1. Impact strength (Izod) evaluation measurement: The rubber-modified styrene-based resins of Examples 1 to 4 and Comparative Examples 1 to 5 were injected, and were subjected to a standard method according to ASTM D-256 (23 ° C, with a gap) Standard test piece was prepared for 1/4 inch thick test piece, and then tested according to ASTM D-256 (unit: Kg-cm/cm).

2. Measurement of content of dimer and trimer in rubber-modified styrene resin: 1 g of each of the rubber-modified styrene resins of Examples 1 to 4 and Comparative Examples 1 to 5 was dissolved in acetone, followed by Methanol was added to cause aggregation of the high molecular weight polymer, and the supernatant was taken and quantitatively analyzed by a gas chromatograph equipped with a flame ionization detector of Hewlett Packard Co., Ltd., 5890A.

3. Melting coefficient (indicating fluidity, melt index, 200 ° C, 5 kg; referred to as MI) Evaluation and measurement: The rubber-modified styrene resins of Examples 1 to 4 and Comparative Examples 1 to 5 were subjected to ASTM standard D-1238 method. carry out testing.

4. Tensile strength (Tsy) evaluation measurement: The rubber-modified styrene-based resins of Examples 1 to 4 and Comparative Examples 1 to 5 were tested in accordance with ASTM D-638, and the unit was kg/cm ² .

5. Elongation ratio (EL) evaluation measurement: The rubber-modified styrene-based resins of Examples 1 to 4 and Comparative Examples 1 to 5 were tested in accordance with ASTM D-638, and the unit was %.

6. Dimensional expansion thickness (Die Swell) evaluation and measurement: The rubber modified styrene resin of Examples 1 to 4 and Comparative Examples 1 to 5 was extruded at a temperature of 220 ° C through a 3 mm mold using a puller (Thermo scientific HAAKE polymer QC). After the die is pushed out, the extruded resin is conveyed through a conveying belt (transport speed of 4.8 m/min) downstream of the die so that the resin has a thickness of the molded article on the conveying belt, and the thickness of the molded article on the conveying belt is measured. The unit is mm.

7. Softening point temperature evaluation measurement: The rubber-modified styrene-based resins of Examples 1 to 4 and Comparative Examples 1 to 5 were measured for softening point temperature (Vicat softening temp.) in accordance with ASTM D-1525, and the unit was °C.

8. Molding evaluation test: The rubber-modified styrene-based resins of Examples 1 to 4 and Comparative Examples 1 to 5 were subjected to an injection machine type NIGATA 160, and the injection conditions were: injection temperature 220 ° C, rate of fire 25%, and injection pressure. 40%, mold temperature 50 ° C, mold 150 * 150 * 6mm, short shot shot 50 mold, remove the contaminants on the mold surface with a razor.

◎: excellent; ○: good; ╳: not good; ╳╳: serious.

9. Evaluation of heat-resistant discoloration property: The rubber-modified styrene-based resins of Examples 1 to 4 and Comparative Examples 1 to 5 were prepared by an injection molding machine type NIGATA 160 under the conditions of injection temperature of 270 ° C to obtain 80*. A 100*2 mm test piece was visually evaluated for the degree of discoloration of the test piece.

◎: no discoloration; ○: slight discoloration; ╳: large discoloration; ╳╳: severe discoloration.

As is clear from the results of Table 1, the total contents of the dimeric or trimeric bodies derived from the styrene monomer and the nitrile vinyl monomer in the rubber-modified styrene resin of Examples 1 to 4 were 1,873, respectively. Ppm ~ 3,250 ppm, during the high-temperature processing and molding process, it will not be precipitated on the surface of the mold after being heated and volatilized due to the presence of the two or three kinds of bodies, so that the mold is fouled. Meanwhile, the copolymer content of the continuous phase ranges from 84.8 wt% to 87.3% by weight, and the rubber particle content of the dispersed phase ranges from 12.7% by weight to 15.2 wt%, so that the rubber modified styrene resin has better properties. The processed property, and the molded article formed therefrom has better mechanical properties and is excellent in heat discoloration resistance.

As is clear from the results of Table 2, the total content of the dimeric or trimeric body derived from the styrene monomer and the nitrile vinyl monomer in the rubber-modified styrene resin of Comparative Examples 1 to 3 was 6,753 ppm. ~9,855 ppm, in the process of high-temperature processing, due to the presence of two or three kinds of bodies, it will be volatilized on the surface of the mold after being heated and volatilized, so that the mold is stained. At the same time, the rubber-modified styrenic resin has poor processing properties.

The styrene-based monomer and the nitrile-based vinyl monomer in the rubber-modified styrene-based resin of Comparative Example 4 have a small content of the di- or tri-dimers, and the mold does not cause mold staining. Since the rubber particle content is less than 10% by weight and does not contain a absorbing structure, the rubber-modified styrene-based resin has poor physical properties and workability, and the heat-resistant discoloration property of the molded article is poor.

The total content of the dimeric or trimeric body derived from the styrene monomer and the nitrile vinyl monomer in the rubber-modified styrene resin of Comparative Example 5 was 12,377 ppm, which was formed during the high-temperature processing. Because of the presence of the dimeric or trimeric body, it is precipitated on the surface of the mold after being volatilized by heating, so that the mold is seriously stained.

In summary, the content of the dimeric or trimeric body derived from the styrene monomer and the nitrile vinyl monomer in the rubber modified styrene resin is 5,000 ppm or less, and the copolymerization is controlled. The content of the material and the rubber particles, and the rubber particles are designed to have a absorbing and non-occluding structure, which not only improves the processing properties of the rubber-modified styrene resin, but also reduces the process during extrusion molding. The occurrence of mold contamination is caused, and a molded article which does not impair the rubber-modified styrene-based resin itself and has a good heat-resistant discoloration property can be obtained, and the object of the present invention can be achieved.

The above is only the preferred embodiment of the present invention, and the scope of the invention is not limited thereto, that is, the simple equivalent changes and modifications made by the scope of the invention and the description of the invention are All remain within the scope of the invention patent.

Claims (9)

A rubber modified styrene resin comprising: a continuous phase formed by a copolymer of 50% by weight to 90% by weight; and a dispersed phase formed by 10% by weight to 50% by weight of rubber particles, wherein the copolymer comprises 50% by weight to 90% by weight of the styrene monomer unit and 10% by weight to 50% by weight of the nitrile vinyl monomer unit; the rubber particles have a absorbing structure and a non-occluding structure; the rubber modified styrene The total content of the dimeric or trimeric body derived from the styrene monomer and the nitrile vinyl monomer in the resin is 5,000 ppm or less based on 100 parts by weight of the rubber-modified styrene resin. The rubber-modified styrene-based resin according to the first aspect of the invention, wherein the rubber-modified styrene-based resin has a styrene-based monomer and a nitrile-based vinyl monomer-derived two-component or three The total content of the precursor is from 1,000 ppm to 4,000 ppm per 100 parts by weight of the rubber-modified styrene resin. The rubber-modified styrene-based resin according to the second aspect of the invention, wherein the rubber-modified styrene-based resin has a styrene-based monomer and a nitrile-based vinyl monomer-derived two-component or three The total content of the precursor is 1,200 ppm to 3,500 ppm, based on 100 parts by weight of the rubber-modified styrene resin. The rubber-modified styrene-based resin according to claim 1, wherein the continuous phase is formed from 60% by weight to 89% by weight of the copolymer, and the dispersed phase is from 11% by weight to 40% by weight. % of rubber particles are formed. The rubber-modified styrene-based resin according to the first aspect of the invention, wherein the rubber-modified styrene-based resin is an emulsion polymerized rubber graft copolymer, a block or solution polymerized rubber graft copolymer, and The suspension polymerization ethylene copolymer was prepared by kneading. The rubber-modified styrene-based resin according to claim 5, wherein the rubber-modified styrene-based resin is an emulsion-polymerized rubber graft copolymer of 1% by weight to 25% by weight, and 20% by weight to ～ 90% by weight of the bulk or solution polymerized rubber graft copolymer is obtained by kneading from 9% by weight to 55% by weight of the suspension-polymerized ethylene-based copolymer. The rubber-modified styrene-based resin according to claim 5, further comprising an additive. The rubber-modified styrene-based resin according to the seventh aspect of the invention, wherein the additive is contained in an amount ranging from 0.1 part by weight to 5 parts by weight based on 100 parts by total of the total amount of the rubber-modified styrene resin. Share. A molded article of a rubber-modified styrene-based resin obtained by subjecting a rubber-modified styrene-based resin according to any one of claims 1 to 8 to a kneading process.