CN1152006A - Styrenic resin composition - Google Patents

Abstract

A styrenic resin composition comprising: 5 to 90% by weight of a graft copolymer obtained by polymerizing a rubber graft copolymer (A) and a propylene-based copolymer (B) with a mixture comprising a styrenic monomer, an acrylonitrile-based monomer and optionally a copolymerizable monomer; 5 to 90% by weight of a graft copolymer (D) obtained by polymerizing a diene rubber with a mixture of a styrene monomer, an acrylonitrile monomer and optionally a copolymerizable monomer; 5-90% by weight of a copolymer (E) obtained by polymerizing a rubber emulsion with a mixture of a styrenic monomer, an acrylonitrile monomer and optionally a copolymerizable monomer.

Description

Styrenic resin composition

The present invention relates to a styrenic resin composition, more specifically, the present invention relates to a styrenic resin composition which has the characteristics of uniform gloss and good vacuum formability, and is suitable for manufacturing molded products .

Those familiar with this technical field know that the styrenic resin composition is an impact-resistant resin composition prepared by dispersing a rubber-like graft copolymer in a styrenic copolymer. In terms of application, high-gloss and low-gloss products have their own fields of application, but under the concept of "r overall planning and design", resins are often required to have different degrees of surface gloss, whether they are injection molded or formed by other methods to make the appearance of the surface of the object more harmonious. Therefore, developing a styrenic resin composition with uniform luster has become a subject to be broken through in this technical field.

In order to reduce the influence of processing condition variation on the surface gloss of the molded product and achieve the purpose of uniform gloss in each part of the molded product, the known improvement method is to make the rubber graft copolymer in the resin composition contain three different particle size distribution types. state, such as the content disclosed in the US Patent No. 5,041,498. However, the improvement effect of the above-mentioned improvement method on uniform gloss is limited, and even under certain comparison benchmarks, the effect is relatively poor.

Those who are familiar with this technical field also know that some styrene-based resin compositions are used in the fields of extruded sheet materials and vacuum forming. Moldable resins are also being continuously developed. For example, it is mentioned in Japanese Patent Application No. 60-20916 that the weight ratio of styrene to acrylonitrile in the acetone-soluble components in the composition is between 1.7 and 2.6, and acetone The storage elastic modulus of the insoluble glue component in the range of 0.9×10 ⁹ to 4×10 ⁹ dynes/cm ² can improve the vacuum formability of the resin, but the improvement effect is not obvious.

In view of this, the inventors of the present case have developed a styrene-based resin composition to address the aforementioned shortcomings.

Therefore, the main purpose of the present invention is to provide a styrenic resin composition with uniform gloss and good vacuum formability.

Styrene fat composition of the present invention mainly comprises:

(1) 5～90% (weight) graft copolymer (C), this graft copolymer (C) is the rubber graft copolymer ( A) and 0.1 to 10 parts by weight of propylene-based copolymer (B) and 100 parts by weight of (a) 45 to 80 parts by weight of styrene-based monomers, (b) 15 to 50 parts by weight of acrylonitrile-based monomers body and (c) a monomer mixture of 0 to 40 parts by weight of an optional copolymerizable monomer is obtained by bulk and/or solution polymerization:

(2) 5～90% (weight) graft copolymer (D), this graft copolymer (D) is by the diene rubber of 5～25 parts by weight and the styrene monomer of 50～80 parts by weight , a monomer mixture of 20-50 parts by weight of acrylonitrile monomer and 0-40 parts by weight of an optional copolymerizable monomer is obtained by bulk and/or solution polymerization;

(3) The copolymer (E) of 5～90% (weight), this copolymer (E) is to be the rubber latex of 0.05～0.8 μ m by the weight average particle diameter of 50～85 parts by weight and 15～50 parts by weight of It is obtained by emulsification graft polymerization of a monomer mixture of styrene monomer, acrylonitrile monomer and optional copolymerizable monomer.

According to the aforementioned composition, a styrenic resin composition having uniform gloss and good vacuum formability can be obtained.

The rubber graft copolymer (A) of the present invention is made of 50-80 parts by weight of butadiene-based rubber emulsion, 15-50 parts by weight of styrene-based monomers and acrylonitrile-based monomers, and 0-30 parts by weight of optional The emulsion of the rubber graft copolymer with a weight average particle size of 0.05-0.8 μm obtained by graft polymerization of other copolymerizable monomers, and then undergoes steps such as coagulation, dehydration, and drying to obtain granular rubber grafts. branch copolymer (A). The butadiene-based rubber emulsion refers to a homopolymer (homopolymer) formed by 60-100% (weight) of a conjugated diene monomer and 0-40% (weight) of a monounsaturated monomer. ), or a copolymer thereof. The conjugated diene monomer can be represented by the following formula:

Wherein, R can be hydrogen, methyl or chlorine, etc., and the monounsaturated monomer can be styrene-based monomer, acrylonitrile-based monomer and (meth)acrylate-based monomer.

The butadiene-based rubber emulsion used in the present invention can be butadiene-styrene copolymer, butadiene-acrylonitrile copolymer, butadiene-methyl methacrylate copolymer, etc.; the above-mentioned butadiene-based rubber The emulsion can be directly polymerized by the aforementioned monomers to obtain a form with a weight average particle size of 0.05-0.8 μm, or it can be first polymerized into a small particle size rubber emulsion with a weight average particle size of 0.05-0.18 μm, and then agglomerated with traditional rubber The method is to agglomerate the rubber emulsion with a small particle size of 0.05-0.18 μm into a rubber emulsion of 0.2-0.8 μm. The rubber agglomeration method may be a chemical agglomeration method by adding an organic acid or metal salt or a polymer agglomeration agent (agglomeration agent) containing a carboxylic acid group, a mechanical agglomeration method by mechanical stirring, or a freezing agglomeration method. The polymer coagulant used in the aforementioned chemical agglomeration method can be, for example, butyl acrylate-methacrylic acid copolymer.

The graft polymerization reaction of the present invention is used to manufacture rubber graft copolymers with a weight average particle diameter of 0.05-0.8 μm. The preparation of described graft copolymer is to utilize conventional graft polymerization technique usually, make rubber-like polymer and styrene monomer, acrylonitrile monomer, and optional (meth)acrylic acid ester Graft polymerization is carried out on the butadiene-based monomer mixture, and at least one polymer is chemically combined or grafted on the butadiene-based rubber. According to the ratio of the monomer to the butadiene rubber and the polymerization conditions, a hard copolymer grafted on the butadiene rubber and a polymer having a desired degree of grafting can be obtained at the same time. Usually, the polymerization conditions in the graft polymerization reaction, the chemical properties of the rubbery polymer, the particle size, the rate of monomer addition, the amount and type of chain transfer agent, emulsifier and other factors will affect the degree of grafting.

The initiator or catalyst added in the aforementioned graft polymerization reaction is usually in the range of 0.01-5.0 parts by weight, preferably 0.1-3.0 parts by weight, based on 100 parts by weight of the total weight of the mixture of polymerizable monomers. The amount to be added depends on the monomer and the polymerization reaction to be polymerized. The aforementioned initiator can be added to the reaction system continuously or in batches to facilitate the graft polymerization reaction.

Moreover, the molecular weight of the above-mentioned graft polymer can be controlled by the temperature of the grafting reaction, and/or adjusted with a relatively small proportion of conventional molecular weight regulators, such as mercaptans, halides, or vinylenes. Specific examples of the molecular weight modifier include: n-dodecyl mercaptan, tert-dodecyl mercaptan.

The graft polymerization reaction can also be controlled by changing the amount of grafted polymer on the rubbery polymer. In general, this effect can be exploited by adding the monomer mixture to the polymerization reaction continuously or incrementally, and preferably simultaneously with the continuous or batchwise addition of the initiator. The initiator can use various known emulsified free radical polymerization initiators, such as: peroxide (peroxy) and azo compounds, and its addition method can be added once or continuously or in batches. ;Appropriate peroxide initiators such as: alkali metal peroxides, persulfates, perborates, peracetates, percarbonates, hydrogen peroxide, etc. Oil-soluble initiators can also be used , For example: dicumyl peroxide, tert-butyl peroxide, cumene hydroperoxide, etc. The above-mentioned polymerization reaction of the butadiene-based rubber emulsion and the monomer mixture is carried out under stirring in an inert gas atmosphere at 20-100° C., and it can also be pressurized to 0-100 P.S.I.G. During the reaction, if 90% of the monomers are to be polymerized, the polymerization time usually needs to be 2-10 hours, preferably 4-8 hours.

The styrene-based monomer used in the present invention can be styrene, α-methylstyrene, α-chlorostyrene, p-tert-butylstyrene, p-methylstyrene, o-chlorostyrene, p -Chlorostyrene, 2,5-dichlorostyrene, 3,4-dichlorostyrene, 2,4,6,-tribromostyrene, 2,5-dibromostyrene, etc., among them, preferably used Styrene or alpha-methylstyrene.

The acrylonitrile-based monomer used may be: acrylonitrile, α-methacrylonitrile, etc.; among them, acrylonitrile is preferred.

The copolymerizable monomer used in the rubber graft copolymer (A) of the present invention can be: (meth)acrylate monomer, maleimide monomer, acrylic acid, anhydrous maleic acid, methyl Ethylene glycolmethacrylate, etc. Wherein (meth) acrylate monomer can be: methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, benzyl methacrylate, hexyl methacrylate, Cyclohexyl methacrylate, dodecyl methacrylate, 2-hydroxyethyl methacrylate, glycidyl methacrylate and dimethylaminoethyl methacrylate, among which methyl methacrylate is preferred .

Maleimide-based monomers can be: maleimide, N-methylmaleimide, N-isopropylmaleimide, N-butylmaleimide, N- Hexylmaleimide, N-octylmaleimide, N-dodecylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide , N-2,3-tolylmaleimide, N-2,4-tolylmaleimide, N-2,3-ethylphenylmaleimide, N-2,4- Ethylphenylmaleimide, N-2,3-butylphenylmaleimide, N-2,4-butylphenylmaleimide, N-2,6-tolylmaleimide imine, N-2,3-chlorophenylmaleimide, N-2,4-chlorophenylmaleimide, N-2,3-bromophenylmaleimide, N- 2,4-bromophenylmaleimide and the like, among which N-methylmaleimide is preferred.

The rubber graft copolymer (A) emulsion with a weight average particle diameter of 0.05-0.8 μm can be prepared by the aforementioned graft polymerization.

Appropriate coagulants must be added to the emulsion of the rubber graft copolymer (A) to coagulate. Generally, the coagulants used include acids such as sulfuric acid and acetic acid, and alkaline earth metal salts, such as calcium salts such as Calcium chloride, magnesium salts such as magnesium chloride, magnesium sulfate, aluminum salts such as aluminum sulfate, among them, alkaline earth metal salts are preferred. The coagulated polymer slurry is dehydrated to remove moisture, and then dried to obtain a granular rubber graft copolymer (A).

The propylene-based copolymer (B) of the present invention is composed of: 10 to 100% (by weight) of at least one monomer selected from (meth)acrylate monomers and acrylonitrile monomers, 0 to 80 % (weight) styrene-based monomer, and 0 to 30% (weight) of other optional copolymerizable monomers; and the propylene-based copolymer (B) can be styrene-acrylonitrile copolymer, Methyl acrylate-styrene-acrylonitrile copolymer, polymethyl methacrylate and styrene-methyl methacrylate copolymer, etc. The polymerization method can be various polymerization methods such as solution, bulk, emulsion or suspension polymerization.

The styrene-based monomers, acrylonitrile-based monomers, (meth)acrylate-based monomers, and rubber graft copolymer (A) used in the above-mentioned propylene-based polymer (B) are the same as described above, and here No more details. Other copolymerizable monomers that are optional as needed may be acrylic acid, anhydrous maleic acid, ethylene glycol methacrylate, and maleimide-based monomers.

The graft copolymer (C) of the present invention is 0.1 to 10 parts by weight of the rubber-based copolymer (A), 0.1 to 10 parts by weight of the propylene-based copolymer (B), and the following units with a total weight of 100 parts by weight The mixture of solids is obtained by bulk and/or solution polymerization. The monomer mixture comprises: 45-80 parts by weight of styrene-based monomers, 15-50 parts by weight of acrylonitrile-based monomers and 0-40 parts by weight of optional copolymerizable monomers.

Specifically, in the present invention, the raw material solution formed by mixing and dissolving the aforementioned monomers, rubber graft polymer (A), propylene-based copolymer (B), and optional solvents as needed is fed into the reactor Polymerization; or mix and dissolve part of the aforementioned monomers, rubber graft copolymer (A), propylene-based copolymer (B), and optional solvents as required to form an independent raw material solution, and then make the remaining monomers Form another raw material solution, and then send the two raw material solutions into the reactor for polymerization.

The aforementioned raw material mixture can be dissolved in a traditional dissolving tank with high shear stress and high stirring speed. Stirring blades, etc., under sufficient time, can completely dissolve the above-mentioned rubber graft copolymer (A) and propylene-based copolymer (B) into a solution state, so as to facilitate the operation of pumping into the reactor . The graft copolymer (C) of the present invention can be completed by continuous bulk or solution polymerization. Said reactors include: columnar flow reactors, completely mixed (CSTR) reactors, or tubular reactors with static mixing elements. The number of said reactors can be one, or two or more, and the reaction can be carried out with the addition of a chain transfer agent and an initiator.

After the reaction in the aforementioned reactor, the conversion rate reaches 40-90% (weight), and finally the reacted reaction mixture is sent to a volatilization device to remove unreacted monomers and solvents to obtain graft copolymerization. Object (C). When making the graft copolymer (C) of the present invention, a polymerization initiator can be added to the reaction, and the polymerization initiator includes acyl peroxides, peroxyesters, peroxyketals, peroxycarbonate Classes, and azo compounds with nitro and cyclohexane rings, etc. The addition amount of the polymerization initiator is 0.01-1.0 parts by weight based on 100 parts by weight of the total weight of the monomer mixture.

The reaction temperature of the above-mentioned reactor is controlled at 80-200°C, preferably in the range of 90-160°C, and the pressure of the reactor is controlled at 1-5 kg/ ^cm2 , and the raw material solution is in the reactor The residence time is preferably between 1 and 5 hours.

In the composition of the present invention, the content of the graft copolymer (C) is 5 to 90% by weight. When its content is less than 5% (weight), the resin cannot obtain superior vacuum formability, and the gloss uniformity of the resin is not good; if its content is more than 90% (weight), it will be impacted due to insufficient rubber content. Poor strength.

The rubber graft copolymer (A) used in the raw material solution of the graft copolymer (C) is 0.1 to 10 parts by weight. If the usage amount of the rubber graft copolymer (A) is higher than 10 parts by weight, the viscosity of the feed solution will be too high, the dissolution and dispersion will be difficult, and the pumping operation will be difficult. The propylene-based copolymer (B) used in the present invention accounts for 0.1 to 10 parts by weight in the raw material solution of the graft copolymer (C). When its consumption is lower than 0.1 weight part, rubber graft copolymer (A) is easy to coagulate together, and can't be dispersed and dissolved in the solution completely, causes the difficulty of pump delivery operation, and the graft copolymer (A) prepared after reaction C) will contain rough particles, and the finished resin composition will have fish eye (fish eye) surface defects, which is not good in appearance, and the effect of improving gloss uniformity will be reduced; if the addition of propylene-based polymer (B) is high In 10 parts by weight, the viscosity of the feed solution is too high, the operation is difficult, and the repeated polymerization and reprocessing of the excess propylene-based polymer (B) is not economical.

When the amount of the rubber graft copolymer (A) used in the raw material solution of the graft copolymer (C) is less than 0.1 parts by weight, a resin with good vacuum formability and uniform gloss cannot be obtained when blended as described later. combination.

The grafting rate of the rubber graft copolymer (A) of the present invention is 10-40%, and when the molecular weight of the hard copolymer grafted on the rubber is between 40,000-120,000, better vacuum formability can be obtained. resin composition. The graft ratio referred to in the present invention refers to the ratio (%) of the hard copolymer grafted on the rubber to the rubber.

The graft copolymer (D) of the present invention is obtained by bulk or solution polymerization, and is composed of 5 to 25 parts by weight of diene rubber, 50 to 80 parts by weight of styrene monomer, and 50 to 80 parts by weight of acrylonitrile monomer. 20-50 parts by weight of monomer, and 0-40 parts by weight of other optional copolymerizable monomers; the production method is to pre-dissolve diene rubber in monomer and/or solvent, and then pump it into the reaction tank For the graft polymerization reaction, the reaction tank can be composed of multiple combinations, and it is generally best to use a kettle-type reaction tank with a strong stirrer. The monomer and diene rubber are mixed into a uniform state, and then polymerized in a continuous manner. During the polymerization, a tower-type piston reaction tank can also be used. Of course, an appropriate chain transfer agent can also be added during the reaction. (eg: tert-dodecyl mercaptan) to control its molecular weight.

The diene-based rubber applicable to the present invention has conjugated diene rubber, preferably has for example butadiene rubber, isoprene rubber, chloroprene rubber etc.; Wherein, butadiene rubber has high cis ( Hi-Cis) content and low-cis (Low-Cis) content; in high-cis rubber, the typical weight composition of cis (Cis)/vinyl (Vinyl) is 94-98%/1-5% , the rest of the composition is trans (Trans) structure; its Mooney viscosity is between 20 and 120, and the molecular weight range is preferably 100,000 to 800,000; in low cis rubber, the typical weight composition of cis/vinyl is in the range of 20 to 40%/1~20%, the rest is trans structure, and the Mooney viscosity is between 20~120. Other suitable rubber materials are: acrylonitrile rubber, styrene/butadiene rubber, or mixtures of different rubbers mentioned above. Styrene/butadiene rubber is commonly known as SBR. The styrene/butadiene copolymer rubber suitable for the present invention can be in the form of two-stage (di-block) copolymerization, three-stage (tri-block) copolymerization, random copolymerization (random) or Star copolymerization (startype). The weight ratio of styrene/butadiene rubber is preferably in the range of 5/100 to 80/20, and the molecular weight is preferably in the range of 50,000 to 600,000. The aforementioned rubbers suitable for the present invention are preferably butadiene rubber and styrene/butadiene rubber, among which butadiene rubber is more preferable.

As for the styrene monomers, acrylonitrile monomers, (meth)acrylic monomers used in the graft copolymer (D), the types of other copolymerizable monomers are the same as those of the rubber graft copolymer ( The monomers used in A) will not be described in detail here.

The graft copolymer (D) obtained by bulk or solution polymerization has a rubber weight average particle size of 0.5-10 μm, preferably 0.8-7.0 μm. The blending ratio of the aforementioned graft copolymer (D) in the composition of the present invention is also limited, and the usage range is preferably between 5 and 90% by weight. When the blending ratio is less than 5% by weight, the vacuum formability of the resin is not good; if the amount is more than 90% by weight, the tensile strength of the composition will decrease.

The preparation method of the graft copolymer (E) of the present invention is the same as that of the rubber graft copolymer (A), and the graft copolymer (E) and the rubber graft copolymer (A) can have the same composition, or are different compositions, but based on a better balance between vacuum formability, gloss uniformity, rigidity and fluidity, the grafting ratio of the graft copolymer (E) is between 18% and 80%, and its grafting The molecular weight of the rigid copolymer is preferably between 40,000 and 200,000. When the grafting rate is lower than 18% or the molecular weight of the grafted rigid copolymer is lower than 40,000, the impact strength and rigidity of the resin are not good, and when the grafting rate is greater than 80% or the molecular weight is higher than 200,000, the fluidity of the resin is poor . The content of the above-mentioned graft copolymer (E) in the composition of the present invention is 5 to 90% by weight. When the content is below 5% by weight, the impact strength of the resin composition is insufficient, and if the content is more than 95% by weight, the fluidity and vacuum formability are poor.

With above-mentioned graft copolymer (C) 5～90% (weight), graft copolymer (D) 5～90% (weight) and graft copolymer (E) 5～90% (weight) according to general mixing The styrenic resin composition of the present invention having excellent vacuum formability and gloss uniformity can be obtained by blending in a training device.

General kneading devices include single-screw and twin-screw extruders, kneading drums and internal kneaders, etc., and various known additives may or may not be included in the styrenic resin composition, such as: stabilizer, Lubricants, flow aids, lump release agents, antioxidants, antistatic agents, fillers, glass fibers, pigments and the like.

The following examples and physical property tests further describe the present invention in detail. Unless otherwise specified, the amounts of each component in the following examples and comparative examples are expressed in weight percentages and parts by weight. <Preparation Example 1> Modeling of Rubber Branches (A-1): The weight of the ingredient weight is 1,3-butadiene 150.00 potassium sulfate solution (1 %) 15.00 potassium oleate 2.00 steamed water 190.00 diaceyl acrylic acid Ethylene glycol ester 0.13

According to the above formula, react at a reaction temperature of 65°C for 12 hours to obtain a synthetic rubber latex with a conversion rate of 94%, a solid content of about 40%, and a flat particle size of 0.1 μm.

In addition, the following components are made of polymer condensate containing carboxylic acid-based: ingredient weights of acrylite 90.0 methyl acrylic 10.0 potassium sulfate solution (1 %) 0.5 sodium dulate sulfate solution (10 %) 0.5 positive-positive- Lauryl Mercaptan 1.0 Distilled Water 200.0

According to the above formula, react at a reaction temperature of 75°C for 5 hours to obtain a carboxylic acid group-containing polymer coagulant with a conversion rate of about 95% and a pH of 6.0.

Afterwards, the synthetic rubber latex (dry weight) of agglomeration 100 weight part is utilized the polymer coagulant (dry weight) containing carboxylic acid group of 3 weight parts, and the pH value of the obtained agglomerated rubber latex is 8.5, weight average The particle size is 0.31 μm.

Finally, the agglomerated rubber emulsion was used for graft polymerization according to the following formula to prepare the rubber graft copolymer (A-1). Equipment weight attachment to the rubber emulsion (dry weight) 100.0 成 成 25.0 acryline 8.3 uncle-duoliosteriol 2.0 isopenophenyl hydrogen peroxide 3.0 iron sulfate solution (0.2 %) 3.0 sodium sulfate formaldehyde solution (10%) 0.9 EDTA solution (0.25%) 3.0

According to the prepared rubber graft emulsion of above table formula coagulation with calcium chloride, just can make the required rubber graft copolymer (A-1) of the present invention (rubber content is 75% (weight)), its weight The average particle diameter was 0.31 μm, the graft ratio was 30.5%, and the molecular weight of the grafted styrene-acrylonitrile copolymer was 63,000. <preparation example 2> the preparation of rubber graft copolymer (A-2):

The synthetic rubber latex (rubber weight average particle size is 0.1 μm) obtained in <Preparation Example 1> was directly grafted with the formulation in the following table to obtain a rubber graft copolymer (A-2). Ingredient weight synthetic rubber gel proof (0.1 μm) (dry weight) 100.0 苯 成 32.4 acrylyl 12.6 uncle-duoliosyl 2.0 isoprophexyl hydrogen hydrogen peroxide 3.0 sulfate solution (0.2 %) 3.0 sodium sulfate 3.0 Formaldehyde solution (10%) 0.9 EDTA solution (0.25%) 3.0

According to the prepared rubber graft emulsion of the formula in the above table coagulated with calcium chloride, the required rubber graft copolymer (A-2) of the present invention (rubber content 69% (weight)) can be obtained, and its weight average The particle diameter was 0.1 μm, the graft ratio was 42%, and the molecular weight of the grafted styrene-acrylonitrile copolymer was 70,000. <Preparation Example 3-1> Preparation of Propylene-Based Copolymer (B-1):

With the speed of 12 kilograms/hour, the raw material that is formed into styrene 75% (weight), methyl methacrylate 25% (weight) is mixed, then ethylene distearamide is mixed with 3.0 gram/hour, benzene peroxide Formyl and tert-dodecyl mercaptan and the recovery liquid mentioned later are combined as a raw material liquid, and the internal temperature is maintained at 108 ° C and the volume is 45 liters of continuous tank reactor with a stirrer, and the reaction is carried out. The proportion of toluene in the liquid was kept at 15%, while the polymerization rate was kept at 55%.

After the reaction solution is passed through a volatilization device to remove volatile components, the particles of the propylene-based copolymer required by the present invention can be obtained. On the other hand, the removed volatile components are condensed by a condenser as a recovery liquid, and are continuously reused with the aforementioned raw material mixture. In this way, the reaction rate is adjusted by the amount of benzoyl peroxide, or the amount of tert-dodecyl mercaptan is adjusted; and the styrene-methyl sulfide with a melt flow index of 1.2 is made at a rate of about 12 kg/hour. Methyl acrylate copolymer (B-1). <Preparation example 3-2> the preparation of propylene-based copolymer (B-2):

The preparation method is the same as <Preparation Example 3-1>, except that the monomer composition is 78% (weight) of styrene and 22% (weight) of acrylonitrile, and the styrene-acrylonitrile copolymer (B-2) can be obtained . <preparation example 4> the preparation of graft copolymer (C):

First mix the following ingredients to make the raw material solution: the ingredient weight 71.90 acryline 腈 28.10 athylene 7.00 rubber branch cluster (A-2) (such as preparation example 2) 4.90 甲 methyl acrylate (asthylene B-1) (as in Preparation Example 3) 1.00 tert-dodecylmercaptan 0.09 benzoyl peroxide (starter) 0.05

The above-mentioned raw material solution is continuously sent in the first reactor at a rate of 22 liters/hour. The volume of this first reactor is 44 liters, the reaction temperature is 120 ° C, the pressure in the reactor is 4 kilograms, and the residence time of the reactant For 2 hours, the stirring speed of the spiral stirring device provided therein is 100 rpm, and a cooling circulation pipe is arranged in the stirring device. The mixture after the reaction in the first reactor is continuously taken out and sent into the second reactor. The structure of the second reactor device is the same as that of the first reactor. When the conversion rate of the mixture reaches 56%, the mixture is taken out again. Send it to a volatilization device to remove unreacted monomers and volatile components, and then extrude and granulate it to obtain a graft copolymer (C-1).

Graft copolymers (C-2), (C-3), (C-4), (C-5), and (C-7) were prepared according to the aforementioned preparation method and the ratios listed in Table 1. <preparation example 5> the preparation of graft copolymer (D):

Use 6.4 parts by weight of polybutadiene (produced by Asahi Kasei Corporation, trade name--Asadene 55AS) as diene rubber, 0.1 parts by weight of tertiary-dodecyl mercaptan and 0.07 parts by weight of benzyl peroxide Acyl is completely dissolved in 64 parts by weight of styrene, 22 parts by weight of acrylonitrile and 30 parts by weight of ethylbenzene as an initiator to form a feed solution; the feed solution is continuously sent into the first reactor The first reactor has a volume of 44 liters, a reaction temperature of 100° C., a spiral stirring device with a stirring speed of 300 rpm, and a cooling circulation pipe in the stirring device. The mixture reacted in the first reactor is continuously taken out and sent into the second reactor, and the structure of the second reactor device is the same as that of the first reactor. When the conversion rate of the mixture reaches 60%, the mixture is taken out and sent to a volatilization device to remove unreacted monomers and volatiles, and then extruded and granulated to obtain a compound with a weight average particle size of 1.1 μm. branch copolymer (D). <preparation example 6> the preparation of graft copolymer (E):

The synthesis of rubber emulsion is the same as Preparation Example 1, but the agglomeration treatment is changed to agglomerate the synthetic rubber latex of 100 weight parts with the polymer coagulant containing carboxylic acid group of 3.5 weight parts, and the pH value of the obtained rubber emulsion is 8.5, the rubber particle size is about 0.28 μm, and the graft polymerization reaction is carried out according to the following formula to obtain the graft copolymer (E). Equipment weight attachment to the rubber emulsion (dry weight) 100.0 苯 成 40.4 acryline 13.4 uncle-duoliol sulfenol 2.0 isopenophenyl hydrogen peroxide 3.0 ferrite sulfate (0.2 %) 3.0 sodium sulfate formaldehyde solution (10%) 0.9 EDTA solution (0.25%) 3.0

The weight average particle diameter of the graft copolymer (E) was 0.28 μm, the graft ratio was 42%, and the molecular weight of the grafted styrene-acrylonitrile copolymer was 80,000.

The test standards for physical properties and molding appearance measured in the following examples and comparative examples are as follows: * Tensile strength: tested according to the ASTM D-683 standard, and the unit is expressed in kilograms/cm2. *Izod impact strength (IZOD): Tested according to ASTM D-256 standard, the unit is expressed in kg.cm/cm. * Gloss (gloss uniformity): Tested by Gardner (Gardner 60°Incidence angle) according to ASTM D-523 standard, the unit is %, the test piece is an injection product with a length of 300mm, a width of 25mm, and a thickness of 3mm. The fan-shaped gate distance Measure the gloss at 5cm, 15cm, and 25cm from the gate at the edge of 15mm, which can be used as a method for judging the uniformity of gloss. The smaller the difference between the three values, the better the uniformity of gloss. *Appearance: The above-mentioned glossy test pieces are visually inspected, those with flat appearance are indicated by ○, and those with grainy protrusions or fish eyes on the surface are indicated by ×. *Vacuum formability: The resin is extruded into a sheet with a thickness of 3.175m/m by a single-screw extruder L/D=28, D=90m/m (Gloucester Engineering Co., USA), and then cut into the above tensile strength For the strength-shaped test piece (300mm×19mm), clamp one end of it and hang it in a 180°C incubator for 15mm, and measure the length change of the 50mm-long part in the middle before and after the test, according to: length after test (mm) / test The front length (50mm) × 100% is calculated and expressed in %. When the value is larger, the vacuum formability is worse, which means that the board material is more sensitive to temperature changes, and it is easy to cause the thickness of the molded product to be different during the vacuum forming process. average situation. Example <Example 1>

In dry state, 46.1% (by weight) of graft copolymer (C-1) (made by Preparation Example 4), 31.3% (by weight) of graft copolymer (D) (made by Preparation Example 5) ), 22.6% (by weight) of graft copolymer (E) (made by Preparation 6) blending; the above-mentioned blend is then blended into a homogeneous melt in a blender, and the melt is then It was extruded into strands and cut into granular plastics for crop testing; the measured results are shown in Table 2. <Example 2>

According to the formula in Table 2, the raw materials were mixed evenly, and then treated according to the treatment method of Example 1, and formed into test pieces for testing. The measured physical properties are listed in Table 2. <Example 3>

According to the formula in Table 2, the raw materials were mixed evenly, and then treated according to the treatment method of Example 1, and formed into test pieces for testing. The measured physical properties are also listed in Table 2. <Example 4>

According to the formula in Table 2, the raw materials were mixed evenly, and then treated according to the treatment method of Example 1, and formed into test pieces for testing. The measured physical properties are also listed in Table 2. <Example 5>

According to the formula in Table 2, the raw materials were mixed evenly, and then treated according to the treatment method of Example 1, and formed into test pieces for testing. The measured physical properties are also listed in Table 2. <Comparative example 1>

With the operating condition of embodiment 1, difference is: graft copolymer (C) uses (C-6) as in table 1 instead, that is to say, graft copolymer (C) does not contain rubber graft copolymerization Object (A), the prepared test piece is also tested for various physical properties, and the results are shown in Table 2. <Comparative example 2>

With the operating condition of embodiment 1, but the consumption of graft copolymer (C-1) is changed into 72.4% (weight), the consumption of graft copolymer (D) is changed into 2.0% (weight), graft copolymer ( The amount of E) was changed to 25.6% (weight), and the physical properties of the molded test pieces were also tested, and the results are shown in Table 2. <Comparative example 3>

With the operating condition of embodiment 1, but graft copolymer (C) changes graft copolymer (C-7) shown in table 1 into, promptly does not contain propylene-based copolymer (B) in graft copolymer (C) ), the formed test pieces were also tested, and the results are also shown in Table 2. <Comparative example 4>

Resin composition is made up of: the graft copolymer (D) of 81.0% (weight) and the graft copolymer (E) of 19.0% (weight), all the other treatment modes are identical with embodiment 1, that is, in the resin composition In the absence of the graft copolymer (C), the molded test pieces were also tested, and the test results are also shown in Table 2.

From the test results of Comparative Example 1, it can be seen that if the graft copolymer (C) of the present invention does not contain the rubber graft copolymer (A), the resin composition with excellent vacuum formability and gloss uniformity cannot be obtained. The test result of Comparative Example 2 shows that when the graft copolymer (D) content is less than 5% (weight), the vacuum formability of the resin is not good, and when the graft copolymer (C) does not contain ethylenic copolymer When compound (B), not only the glossiness is lower, the gloss is not uniform, but also the appearance of the finished resin composition is not good, as can be seen from the test results of Comparative Example 3; ), a resin composition with excellent vacuum formability and gloss uniformity cannot be obtained, and the tensile strength of the finished product is also relatively poor, which can be proved by the test results of Comparative Example 4.

Looking at Examples 1-5 again, the present invention can indeed improve the vacuum formability and gloss uniformity of the styrenic resin composition through the limitations of the aforementioned components and usage amounts, so as to reduce the impact of processing condition variation on the surface gloss of the finished product. influence, and make the application of the composition more perfect in the process of increasingly large-scale plate materials, and can be used by the industry.

The foregoing is only an illustration of the invention by way of a preferred possible embodiment. It will be apparent to those skilled in the art that modifications or variations of the present invention may be made within the spirit and scope of the present invention.

Table 1 (parts by weight) The serial number of the graft copolymer (C) (C-1) (C-2) (C-3) (C-4) (C-5) (C-6) (C-7) Rubber Graft Copolymer (A) (A-2) 4.9 (A-1) 3.1 (A-2) 4.9 (A-2) 5.2 (A-2) 9.6 -0 (A-2) 4.8 Propylene-Based Copolymer (B) (B-1) 1.1 (B-1) 1.1 (B-2) 1.1 (B-1) 3.9 (B-1) 4.5 (B-1) 1.1 -0 Styrene 71.9 71.9 68.1 71.9 71.9 71.9 71.9 Acrylonitrile 28.1 28.1 26.6 28.1 28.1 28.1 28.1 N-phenylmaleimide 0 0 5.3 0 0 0 0

Table 2 experiment number Example 1 Example 2 Example 3 Example 4 Example 5 Comparative example 1 Comparative example 2 Comparative example 3 Comparative example 4 ingredients Graft copolymer (C) % by weight (C-1) 46.1 (C-2) 46.1 (C-3) 46.1 (C-4) 46.1 (C-5)41.5 (C-6) 43.4 (C-1)72.4 (C-7) 46.1 -0 Graft copolymer (D) % by weight 31.3 31.3 31.3 31.3 38.6 28.6 2.0 31.3 81.0 Graft copolymer (E) % by weight 22.6 22.6 22.6 22.6 19.9 28.0 25.6 22.6 19.0 Pilot projects Izod impact strength (kg-cm/cm) 29.6 30.8 29.0 29.2 29.4 30.1 29.5 28.9 26.6 Tensile Strength (kg/cm2) 369 371 365 367 366 358 377 366 313 Vacuum formability (%) (180°C, 15 minutes sag length 5.3 5.5 5.9 5.6 6.1 14.6 17.4 8.5 30.1 Gloss 5cm 88.1 85.7 84.6 85.9 84.5 84.1 87.2 82.3 86.6 15cm 84.6 82.4 83.7 84.1 83.1 80.7 85.3 79.2 81.5 25cm 83.5 82.1 81.7 83.3 81.8 75.5 83.1 75.2 76.2 Uniformity % (5cm-25cm) 2.6 3.6 2.9 2.6 2.1 8.8 4.1 7.1 10.4 Exterior ○ ○ ○ ○ ○ ○ ○ x ○

Claims (3)

1. composition of styrene resin comprises:

(1) 5～90% (weight) graft copolymer (C), this graft copolymer (C) be the weight average particle diameter by 0.1～10 weight part be the rubber graft copolymer (A) of 0.05～0.8 μ m and 0.1～10 weight part propenyl based copolymer (B) and 100 weight parts to comprise (a) 45～80 parts by weight of styrene be monomer, (b) the acrylic monomer of 15～50 weight parts and (c) monomer mixture of the optional copolymerizable monomer of 0～40 weight part carry out body and or solution polymerization obtain:

(2) 5～90% (weight) graft copolymer (D), this graft copolymer (D) are that the monomer mixture of the optional copolymerizable monomer of monomer and 0-40 weight part carries out body and/or solution polymerization obtains by styrenic monomers, the 20-50 parts by weight of acrylonitrile of the diene series rubber of 5～25 weight parts and 50～80 weight parts;

The multipolymer of (3) 5～90% (weight) (E), this multipolymer (E) are that the mixture of the styrenic monomers, acrylic monomer of the rubber latex of 0.05～0.8 μ m and 15～50 weight parts and optional copolymerizable monomer carries out the emulsification graft polymerization and obtains by the weight average particle diameter of 50～85 weight parts.

2, composition as claimed in claim 1, wherein, the graft copolymer that described rubber graft copolymer (A) obtains for emulsion polymerization.

3, composition as claimed in claim 1, wherein, the percentage of grafting of described rubber graft copolymer (A) is 10～40%, the molecular weight of grafted hard multipolymer is 40,000～120, between 000.