KR20040082875A - Thermoplastic transparent resin composition and process for preparaing thereof - Google Patents

Abstract

PURPOSE: A thermoplastic transparent resin composition and a preparation method thereof are provided to improve stability, impact resistance, humid/heat resistance and heat resistant coloring properties with a reduced amount of coagulated solids. CONSTITUTION: The preparation method of the thermoplastic transparent resin composition comprises: (a) adding a non-reactive emulsifier to butadiene to prepare polybutadiene rubber latex; (b) mixing 15-50wt% of the polybutadiene rubber latex prepared above, 30-50wt% of methacrylate alkyl ester or acrylate alkylester compound, 15-30wt% of an aromatic vinyl compound and 2-15wt% of vinyl cyanide compound; and (c) adding 0.1-2pts.wt of a reactive emulsifier to 100pts.wt of the monomer mixture to conduct graft copolymerization.

Description

Thermoplastic transparent resin composition and its manufacturing method {THERMOPLASTIC TRANSPARENT RESIN COMPOSITION AND PROCESS FOR PREPARAING THEREOF}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic transparent resin composition having excellent heat colorability, heat and moisture resistance, and impact resistance, and more particularly, to a polybutadiene rubber latex, (meth) acrylic acid alkyl ester compound, aromatic vinyl compound, vinyl cyan compound, and the like. The present invention relates to a styrene-based thermoplastic transparent resin composition having a small amount of coagulant and having extremely excellent heat colorability, heat-and-moisture resistance, and impact resistance by using a reactive emulsifier during grafting copolymerization of a monomer of.

The transparent ABS resin, which is transparent by introducing an unsaturated carboxylic acid alkyl ester compound such as acrylic acid alkyl ester or methacrylic acid alkyl ester, into acrylonitrile-butadiene-styrene (ABS) resin having excellent impact resistance, chemical resistance, and processability It has better impact strength than methyl methacrylate (PMMA), and has excellent processability and chemical resistance than polycarbonate, and is widely used for various applications such as home appliances, communication devices, and general goods.

Recently, efforts to make the design revolution by introducing a nude fashion culture and pastel color culture into the product while actively promoting product differentiation have been made. have. As a polymerization method of such a transparent ABS resin, a bulk polymerization method, a solution polymerization method, or a suspension polymerization method may also be used, but emulsion polymerization is easy to control the content of rubber, molecular weight of the matrix resin, etc., and to easily control the polymerization temperature. The law is appropriate. In addition, the emulsion polymerization method using water instead of an organic solvent is an age requirement when environmental regulations are widely tightened.

However, coagulates are liable to occur during emulsion polymerization of the transparent ABS, and the coagulates adhere to the reactor inner wall and the stirrer, making it difficult to control the polymerization temperature, and cause clogging of the pipe during the movement of the latex after polymerization. Becomes In order to solve this problem, a non-reactive emulsifier is used, but in this case, since the antifoaming agent must be added during the aggregation process, the transparency of the transparent resin is reduced. In addition, in the case of molded products of the resin recovered after flocculation, impact resistance is lowered, and it may be a cause of deterioration of heat colorability during high temperature processing.

Recently, in order to solve the above problems in the emulsion polymerization, researches are being conducted to replace the non-reactive emulsifiers that have been used previously with reactive emulsifiers, but the physical properties of impact resistance, heat colorability, and moist heat resistance using reactive emulsifiers are being studied. The example which produced the transparent resin which has is not disclosed yet.

The present inventors have studied to solve the above problems, and as a result, the reactive emulsifier is directly connected to the main chain of the polymer, and thus, unlike the non-reactive emulsifier, the latex can be stabilized with a small amount, thereby significantly reducing the coagulum. In addition, since the addition amount of the antifoaming agent can be reduced, transparency may not be reduced, and since the reactive emulsifier is bound to the polymer main chain, it has been found that the impact resistance, heat complexation resistance, and heat and humidity resistance can be improved.

Based on the above findings, the present invention is to mix polybutadiene rubber latex with monomers such as (meth) acrylic acid alkyl ester compound, aromatic vinyl compound, vinyl cyan compound, etc. in an appropriate mixing ratio, and then add a reactive emulsifier to graft copolymerization. Provided is a styrene-based thermoplastic transparent resin composition having a small amount of coagulated water and extremely excellent in heat coloring, moisture heat resistance, and impact resistance.

In order to achieve the above object, the present invention provides a method for producing a styrene-based thermoplastic transparent resin,

a) a first step of preparing a polybutadiene rubber latex by adding a non-reacting emulsifier to butadiene;

b) 15 to 50% by weight of polybutadiene rubber latex prepared in the first step, 30 to 50% by weight of methacrylic acid alkyl ester or acrylic acid alkyl ester compound, 15 to 30% by weight aromatic vinyl compound, 2 to 15 vinyl cyan compound A second step of mixing the weight percent; And

c) a third step of graft copolymerization by adding 0.1 to 2 parts by weight of a reactive emulsifier with respect to 100 parts by weight of the monomer mixture;

It provides a method for producing a styrene-based thermoplastic transparent resin comprising a.

In addition, the present invention is 15 to 50% by weight of polybutadiene rubber latex, 30 to 50% by weight of (meth) acrylic acid alkyl ester compound, 15 to 30% by weight of aromatic vinyl compound, 2 to 15% by weight of vinyl cyan compound and It provides a styrene-based thermoplastic transparent resin composition containing a reactive emulsifier.

Hereinafter, the method for producing a styrene-based thermoplastic transparent resin of the present invention will be described in detail.

1) Preparation of Polybutanediene Rubber Latex

The particle diameter and gel content of polybutadiene rubber latex used in the manufacture of graft transparent resin greatly affect the physical properties such as transparency and impact strength of the product, so it is important to select appropriate particle size and gel content. Polybutadiene rubber latex preferably has a particle size of 2000 5000 to 5000 Å, gel content of 60 to 98% and swelling index of 12 to 60. At this time, if the average particle size of rubber latex used is less than 2000 Å, transparency is excellent. When impact resistance and fluidity decrease and exceed 5000Å, the impact resistance is good but transparency is not good. In addition, when the gel content is less than 60%, the swelling index is high, the apparent particle size is increased, the impact resistance is excellent, but the transparency is lowered, the impact strength is not good when the gel content is more than 98%.

The polybutadiene rubber latex is 100 parts by weight of 1,3-butadiene, 1 to 4 parts by weight of emulsifier, 0.2 to 1.5 parts by weight of polymerization initiator, 0.5 parts by weight of electrolyte, 0.1 to 0.5 parts by weight of molecular weight regulator, 75 parts by weight of ion-exchanged water. Prepared by reaction.

In the preparation of rubber latex, the polymerization temperature is very important for controlling the gel content and the swelling index, so 65 to 85 ° C. is preferable, and the polymerization time is preferably 20 to 50 hours.

The emulsifiers used in the production of the polybutadiene rubber latex are non-reactive emulsifiers such as alkyl aryl sulfonates, alkali methyl alkyl sulfates, sulfonated alkyl esters, fatty acid soaps, alkali salts of rosin acid, and the like. It can be used as a mixture of the above.

A water-soluble persulfate or a peroxy compound can be used as a polymerization initiator, and an oxidation-reduction system can also be used. Preferred water soluble persulfates are sodium and potassium persulfates and the fat soluble polymerization initiators are cumenehydro peroxide, diisopropyl benzenehydroperoxide, azobis isobutylnitrile, tertiary butyl hydroperoxide, paramethane hydroperoxide, benzoyl peroxide And the like can be used alone or as a mixture of two or more thereof.

As electrolyte, KCl, NaCl, KHCO ₃ , NaHCO ₃ , K ₂ CO ₃ , Na ₂ CO ₃ , KHSO ₃ , NaHSO ₃ , K ₄ P ₂ O ₇ , K ₃ PO ₄ , Na ₃ PO ₄ , K ₂ HPO ₄ , Na ₂ HPO ₄ and the like can be used alone or in mixture of two or more thereof.

As the molecular weight regulator, mercaptans such as primary octyl mercaptan, primary dodecyl mercaptan, tertiary dodecyl mercaptan, and primary tetradecyl mercaptan are mainly used.

2) Preparation of Graft Copolymer

15 to 50% by weight of polybutadiene rubber latex prepared by the above method, 30 to 50% by weight of methacrylic acid alkyl ester or acrylic acid alkyl ester compound, 15 to 30% by weight of aromatic vinyl compound, 2 to 15% by weight of vinyl cyan compound The monomer mixture is graft copolymerized.

The refractive index of the monomer mixture absolutely affects the transparency, and the refractive index is controlled by the mixing ratio of the monomers. That is, since the refractive index of the polybutadiene is about 1.518, in order for the resin to have transparency, the refractive index of the entire grafted component must be adjusted to a similar degree. Therefore, the mixing ratio of the monomers must satisfy formula (1).

Equation (1): RI = Wt _A × RI _A + Wt _S × RI _S + Wt _M × RI _M

Where RI is the refractive index of the graft polymer, where 1.513 ≦ RI ≦ 1.521,

Wt _A is the weight percent of vinyl cyan compound,

RI _A is the refractive index of the vinyl cyan compound (1.52),

Wt _S is the weight percent of the aromatic vinyl compound,

RI _S is the refractive index of the aromatic vinyl compound (1.592),

Wt _M is the weight percent of the (meth) acrylic acid alkyl ester compound,

RI _M is the refractive index (1.49) of the (meth) acrylic-acid alkylester compound.

Since the refractive index of each component of the monomer used is about 1.49 methyl methacrylate, about 1.592 styrene, about 1.518 acrylonitrile, rubber latex 15 to 50% by weight, methacrylic acid alkyl ester or acrylic acid alkyl ester compound 30 to By using 50% by weight, 15 to 30% by weight of an aromatic vinyl compound, and 2 to 20% by weight of a vinyl cyan compound, the refractive index of the entire compound grafted to a degree similar to that of the polybutadiene can be adjusted. It is preferable that the refractive index of all the compounds is 1.513-1.521, and when refractive index is less than 1.513 or more than 1.521, transparency will fall extremely and it is not suitable for this invention.

When the content of the polybutadiene rubber latex is less than 15 parts by weight of the monomer mixture, sufficient impact resistance cannot be obtained. When the content of the polybutadiene rubber latex exceeds 50 parts by weight, the mechanical properties are very poor due to insufficient grafting. Because of the problem of insufficient stability, the preferred content of polybutadiene rubber latex is 15 to 50 parts by weight of the monomer mixture.

The said methacrylic acid alkyl ester compound or the acrylic acid alkyl ester compound is a (meth) acrylic acid methyl ester, (meth) acrylic acid ethyl ester, (meth) acrylic acid propyl ester, (meth) acrylic acid 2-ethylhexyl ester, (meth) acrylic acid decyl ester Or (meth) acrylic acid lauryl ester or the like can be used, and it is particularly preferable to use methyl methacrylate. In addition, when the content of the methacrylic acid alkyl ester compound or acrylic acid alkyl ester compound is less than 30% by weight of the monomer mixture, transparency is inferior, and when the content of the methacrylic acid alkyl ester compound is greater than 50% by weight, the grafting is not performed well, which causes a problem of deterioration of mechanical properties. Therefore, it is preferably included in 30 to 50% by weight.

As said aromatic vinyl compound, styrene, (alpha) -methylstyrene, p-methylstyrene, vinyltoluene, etc. can be used, It is preferable to use styrene especially. In addition, when the content of the aromatic vinyl compound is less than 15% by weight of the monomer mixture, there is a problem inferior in workability, and when the content of the aromatic vinyl compound exceeds 30% by weight, it is difficult to control the refractive index and lower the transparency, so 15 to 30% by weight is preferable.

Acrylonitrile or methacrylonitrile may be used as the vinyl cyan compound, and the amount thereof is preferably 2 to 15 wt%. When the content of the vinyl cyanide compound is less than 2% by weight, the chemical resistance is deteriorated, and when the content of the vinyl cyanide is more than 15% by weight, the color of the resin is changed to yellow, which does not satisfy the consumer's desire for natural color, and during grafting polymerization. There is a problem that production is difficult because a lot of solids (coa rum) is generated.

The addition method of each said component can use the batch administration method, and the method of continuously administering whole or part. In the present invention, it is preferable to take a complex form in which both batch administration and continuous administration methods are used.

The styrenic thermoplastic transparent resin of the present invention is prepared by an emulsion polymerization method using a reactive emulsifier. Reactive emulsifiers are directly linked to the main chain of the polymer, so unlike the non-reactive emulsifiers, latex can be stabilized in a small amount to reduce coagulation, and the amount of antifoaming agent can be reduced, thereby reducing the transparency. . In addition, since it is bonded to the polymer backbone, it is possible to improve impact resistance, heat complexation resistance, and moist heat resistance.

The polymerization temperature is preferably 65 to 85 ° C, and the polymerization time is preferably 3 hours to 10 hours. In addition, when the content of the reactive emulsifier is less than 0.1 parts by weight with respect to 100 parts by weight of the copolymerized monomer mixture, there is a problem that a sufficient latex stability is not obtained. Since the residue remaining on the latex phase without binding to the main chain is left to cause a decrease in moist heat resistance, the preferred content is 0.1 to 2 parts by weight.

Moreover, it is more preferable to use together with 0.2-1.5 weight part of molecular weight regulators, and 0.02-0.3 weight part of polymerization initiators with respect to 100 weight part of monomer mixtures.

The reactive emulsifier used in the present invention includes an anionic reactive emulsifier including an allyl group, a (meth) acryloyl group, and a propenyl group and a nonionic reactive emulsifier which is an ethylene oxide adduct. For example, commercially available is the ADEKA REASOAP SE ^™ series (product of Asahi Denka) which is a sulfonic acid ester of polyoxyethylene allylglycidyl nonylphenyl ether, an anionic reactive emulsifier containing an allyl group.

Commercially available nonionic reactive emulsifiers containing allyl groups include the ADEKA REASOAP NE ^™ series (product of Asahi Denka), which is a polyoxyethylene allylglycidyl nonylphenyl ether. An example of an anionic reactive emulsifier containing a (meth) acryloyl group is ELEMINOL RS ^™ series (manufactured by Sanyo Kasei). HITENOL HS ^™ series (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), which is an ammonium salt of sulfonic acid ester of polyoxyethylene nonyl propenyl ether, an anionic reactive emulsifier containing a propenyl group, is commercialized. The reactive emulsifier used in the present invention may be used alone or in a mixture of two kinds, and may be used in combination with a non-reactive emulsifier.

As a molecular weight modifier, mercaptans, such as primary octyl mercaptan, primary dodecyl mercaptan, tertiary dodecyl mercaptan, and primary tetradecyl mercaptan, are preferable.

As the polymerization initiator, cumene hydroperoxide, diisopropylbenzenehydro peroxide, tertiary butyl hydroperoxide, paramethane hydroperoxide, benzoyl peroxide and the like can be used alone or in a mixture of two or more thereof. In addition, an oxidation-reduction catalyst system comprising a mixture of these peroxides with reducing agents such as sodium formaldehyde succilate, sodium ethylenediamine tetraacetate, ferrous sulfate, dextrose, ascorbic acid, sodium pyrrolate, sodium sulfite, etc. Can be used.

The polymerization conversion rate of the latex obtained after the completion of the polymerization was 98% or more. An antioxidant and a stabilizer were administered to the latex to agglomerate with calcium chloride aqueous solution at a temperature of 80 ° C. or higher, and then dehydrated and dried to obtain a powder. Stability of the graft copolymer latex prepared above was determined by measuring the solidified solids (%) as shown in the following formula (2).

Equation (2):

When the solidified solid content is more than 0.7%, latex stability is extremely low, and it is difficult to obtain a graft copolymer suitable for the present invention due to the large amount of coagulum. After the antioxidant and stabilizer were added to the obtained powder, pellets were prepared using a twin screw extruder at 200 ° C to 230 ° C, and the pellets were injected again to measure their physical properties.

The following examples illustrate the invention in more detail, but do not limit the scope of the invention to the following examples.

Example 1

1) Preparation of Polybutadiene Rubber Latex

In a nitrogen-substituted polymerization reactor (autoclave), 80 parts by weight of ion-exchanged water, 100 parts by weight of 1,3-butadiene, 1.2 parts by weight of potassium rosin salt as emulsifier, 1.5 parts by weight of potassium oleate salt, sodium carbonate (Na ₂ CO) as an electrolyte ₃ ) 0.7 parts by weight, 0.8 parts by weight of potassium hydrogen carbonate (KHCO ₃ ), 0.3 parts by weight of tertiary dodecyl mercaptan (TDDM) as a molecular weight modifier were collectively administered, the reaction temperature was raised to 65 ° C., and then potassium persulfate as an initiator. The reaction was initiated by batch administration of 0.3 parts by weight, the reaction temperature was continuously raised to 85 ° C. for 35 hours, and the reaction was terminated. The obtained rubber latex was analyzed according to the following analysis method.

a) gel content and swelling index

The rubber latex was coagulated with dilute acid or metal salt, washed, dried in a vacuum oven at 60 ° C. for 24 hours, and the resulting rubber mass was chopped with scissors, and then 1 g of rubber sections was placed in 100 g of toluene. After storage in the dark at room temperature for a time, it was separated into sol and gel, and gel content and swelling index were measured according to the following equations (3) and (4), respectively.

The gel content of the prepared rubber latex was measured at 75%, the swelling index was measured at 20.

Formula (3)

Formula (4)

b) particle diameter

The particle size of the rubber latex was measured using a Nicomp 370 HPL (manufactured by Nicomp Co., Ltd.) by a dynamic laser light scattering method.

2) Preparation of Graft Copolymer

30 parts by weight of the polybutadiene rubber latex prepared in 1), 50 parts by weight of ion-exchanged water, and 0.2 parts by weight of HITENOL HS-10 ^TM as an emulsifier were collectively administered to a nitrogen-substituted polymerization reactor at 50 ° C, and the reaction temperature was 78 ° C. The reaction was carried out by raising over 2 hours. Then, 60 parts by weight of ion-exchanged water, 0.4 parts by weight of HITENOL HS-10 ^{TM as a} reactive emulsifier, 46.8 parts by weight of methyl methacrylate, 18.2 parts by weight of styrene, 5 parts by weight of acrylonitrile, and tertiary dodecyl 0.7 parts by weight of mercaptan, 0.048 parts by weight of sodium pyrophosphate, 0.012 parts by weight of dextrose, 0.001 parts by weight of ferrous sulfide, and 0.1 parts by weight of cumene hydroperoxide were continuously administered for 5 hours, followed by 80 ° C. After raising the temperature to 1 hour, the reaction was terminated. After the completion of the polymerization, the polymerization conversion was 99.5% and the solidified content was 0.02%. An antioxidant and a stabilizer were administered to the latex to coagulate with an aqueous calcium chloride solution at a temperature of 80 ° C. or higher, followed by dehydration and drying to obtain a powder. After adding the antioxidant and stabilizer to the obtained powder, pellets were prepared using a twin screw kneader at 200 ° C to 230 ° C, and the pellets were injected again to measure the physical properties according to the following test methods. It was.

a) transparency

The injection molded plate molded article having a thickness of 3 mm was measured in Haze value (%) according to ASTM 1003 and is shown in Table 1.

b) impact resistance (Izod impact strength)

A 1/4 inch injection test piece was measured at 23 ° C in accordance with ASTM D256.

c) moisture and heat resistance

Table 1 shows the difference (Δhaze) between Haze measured at room temperature and the measured value of Haze of the same molded product which was left at 90% humidity and 70 ° C. for 72 hours.

d) heat colorability

After leaving the obtained dry polymer for 15 minutes in the injection molding machine of the molding temperature of 250 degreeC, the degree to which the molded test piece was colored by the following formula is shown in Table 1.

Here, ΔE is the arithmetic mean value of the Hunter Lab values before and after the stay, and the closer to 0, the better the heat colorability.

Example 2

In the same manner as in Example 1, 45.36 parts by weight of methyl methacrylate, 17.36 parts by weight of styrene, and 7 parts by weight of acrylonitrile were grafted onto polybutadiene rubber latex to prepare a styrene-based transparent resin, and then prepare a specimen. The results are shown in Table 1.

Example 3

In the same manner as in Example 1, 48.24 parts by weight of methyl methacrylate, 18.76 parts by weight of styrene, 3 parts by weight of acrylonitrile were subjected to HITENOL HS-20 ^TM as a reactive emulsifier when grafted onto polybutadiene rubber latex. Styrene-based transparent resin was prepared using the same parts by weight as in Example 1, and then a specimen was prepared. The results are shown in Table 1.

Comparative Example 1

In the same manner as in Example 1, but using a non-reactive emulsifier potassium oleate salt in the same parts by weight instead of a reactive emulsifier when preparing the graft copolymer prepared a styrene-based transparent resin and then prepared a specimen 1 is shown.

Comparative Example 2

In the same manner as in Example 1, 51 parts by weight of methyl methacrylate, 14 parts by weight of styrene, and 5 parts by weight of acrylonitrile were grafted onto polybutadiene rubber latex to prepare a styrene-based transparent resin, and then prepare a specimen. The results are shown in Table 1.

Comparative Example 3

In the same manner as in Example 1, 43.3 parts by weight of methyl methacrylate, 21.7 parts by weight of styrene, and 5 parts by weight of acrylonitrile were grafted onto polybutadiene rubber latex to prepare a styrene-based transparent resin, and then prepare a specimen. The results are shown in Table 1.

TABLE 1

As can be seen in Table 1, the Example is low in the content of solid coagulation compared to Comparative Example 1 has excellent stability, and at the same time excellent impact resistance, heat-and-moisture resistance, heat colorability. In addition, it can be seen that the transparency is extremely excellent compared to Comparative Examples 2 and 3.

As described above, the present invention provides a composition of a thermoplastic transparent resin excellent in heat-coloring resistance, heat-and-moisture resistance, and impact resistance, and a method for producing the same.

Claims (14)

In the manufacturing method of the styrene-based thermoplastic transparent resin, a) a first step of preparing a polybutadiene rubber latex by adding a non-reacting emulsifier to butadiene; And b) 15 to 50% by weight of polybutadiene rubber latex prepared in the first step, 30 to 50% by weight of methacrylic acid alkyl ester or acrylic acid alkyl ester compound, 15 to 30% by weight aromatic vinyl compound, 2 to 15 vinyl cyan compound A second step of mixing the weight percent; c) a third step of graft copolymerization by adding 0.1 to 2 parts by weight of a reactive emulsifier with respect to 100 parts by weight of the monomer mixture; Method for producing a styrene-based thermoplastic transparent resin comprising a. The method of claim 1, wherein the content of the vinyl cyan compound, the aromatic vinyl compound and the acrylic acid alkyl ester monomer of the second step satisfy the following formula (1): Equation (1): RI = Wt _A × RI _A + Wt _S × RI _S + Wt _M × RI _M Wherein RI is the refractive index of the graft polymer, and 1.513 ≦ RI ≦ 1.521, Wt _A is the weight percent of vinyl cyan compound, RI _A is the refractive index of the vinyl cyan compound (1.52), Wt _S is the weight percent of the aromatic vinyl compound, RI _S is the refractive index of the aromatic vinyl compound (1.592), Wt _M is the weight percent of the (meth) acrylic acid alkyl ester compound, RI _M is the refractive index (1.49) of the (meth) acrylic-acid alkylester compound. The method of claim 1, wherein the third step is a graft copolymerization method by further adding a molecular weight regulator or a polymerization initiator. According to claim 1, wherein the reactive emulsifier of the third step is an anionic reactive emulsifier comprising an aryl group, a nonionic reactive emulsifier comprising an allyl group, an anionic reactive emulsifier comprising a (meth) acryloyl group And an anionic reactive emulsifier comprising a propenyl group. The method of claim 1, wherein the third step is a graft copolymerization method by further adding a non-reactive emulsifier. The method of claim 1, wherein the polybutadiene rubber latex has an average particle diameter of 2000 GPa to 5000 GPa, a gel content of 60% to 98%, and a swelling index of 12 to 60. The method of claim 1, wherein the methacrylic acid alkyl ester is methyl methacrylate. The method of claim 1, wherein the aromatic vinyl compound is selected from the group consisting of styrene, α-methylstyrene, 0-etherstyrene, p-ethylstyrene, and vinyltoluene. The method of claim 1, wherein the vinyl cyan compound is selected from the group consisting of acrylonitrile, methacrylonitrile and ethacrylonitrile. The styrene of claim 1, wherein the non-reactive emulsifier is selected from the group consisting of alkyl aryl sulfonates, alkali methyl alkyl sulfates, sulfonated alkyl esters, soaps of fatty acids, alkali salts of rosin acids, and mixtures thereof. Method for producing a thermoplastic thermoplastic resin. According to claim 3, wherein the polymerization initiator is at least one selected from the group consisting of cumene hydro peroxide, diisopropyl benzene hydro peroxide, butyl hydroperoxide, paramethane hydroperoxide, benzoyl peroxide and persulfate Method for producing styrene thermoplastic transparent resin. The method of claim 3, wherein the molecular weight modifier is selected from the group consisting of octyl mercaptan, dodecyl mercaptan, dodecyl mercaptan and tetra decyl mercaptan. In the styrene-based thermoplastic transparent resin composition, 15 to 50 wt% of polybutadiene rubber latex, 30 to 50 wt% of methacrylic acid alkyl ester or acrylic acid alkyl ester compound, 15 to 30 wt% of aromatic vinyl compound, 2 to 20 wt% of vinyl cyan compound and 100 parts by weight of the monomer mixture Styrene-based thermoplastic transparent resin composition further comprising 0.1 to 2 parts by weight of a reactive emulsifier. The styrene-based thermoplastic transparent resin composition according to claim 13, wherein the polybutadiene rubber latex has an average particle diameter of 2000 GPa to 5000 GPa, a gel content of 60% to 98%, and a swelling index of 12 to 60.