KR101602531B1 - Manufacturing method of transparent thermoplastic resin having no mold deposit - Google Patents

Abstract

The present invention relates to a method for producing a transparent thermoplastic resin which is excellent in transparency, impact strength and processability and does not cause mold deposit during high-speed continuous injection molding. The present invention relates to: (1) a method for producing a transparent thermoplastic resin from a conjugated diene monomer A step of preparing a rubber latex to produce a rubber latex; (2) a step of producing a resin latex to produce a resin latex by graft copolymerizing a (meth) acrylic acid monomer, an aromatic vinyl monomer and a vinyl cyan monomer to the rubber latex using an initiator; (3) agglomerating the resin latex to obtain a wet powder; And (4) wet co-extruding the wet powder together with the aromatic vinyl-based copolymer to produce pellets.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a transparent thermoplastic resin,

More particularly, the present invention relates to a transparent thermoplastic resin which is excellent in transparency, impact strength and processability, and which does not generate a mold deposit during high-speed continuous injection molding. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transparent thermoplastic resin- ≪ / RTI >

Generally, acrylonitrile-butadiene-styrene resin (hereinafter referred to as "ABS resin") has various characteristics such as styrene processability, rigidity and chemical resistance of acrylonitrile, and impact resistance of butadiene, It has been widely used in automobile appliances, household appliances, OA appliances and the like.

However, since the conventional ABS resin is opaque, there is a disadvantage that its use is limited to products requiring transparency such as a transparent window for a washing machine, a transparent housing for a TV, a transparent duct for a vacuum cleaner, a transparent housing for a game machine,

U.S. Patent No. 3,787,522, JP-A-1988-42940 and EP-A-0703252 disclose a method of producing a rubber-reinforced thermoplastic transparent resin such as a transparent ABS resin, There is a problem that mold precipitation may occur during high-speed continuous injection molding to increase the complex mold structure or injection productivity due to diversification, but there is no mention of improvement method therefor.

As a result of investigating the causes of mold settling, it was found that the use of low molecular weight emulsifiers such as Fatty and the oligomers contained in the polymer produced in the polymerization process were decomposed upon continuous injection at a high speed in a complicated mold structure, It was investigated that it occurred by sedimentation.

Therefore, one object of the present invention is to provide a method for producing a resin composition which is excellent in transparency, impact strength and processability by using a reactive emulsifier instead of a fatty emulsifier generally used in the production of a resin and co- And a method for producing a transparent thermoplastic resin in which a mold deposit is not generated.

A process for producing a transparent thermoplastic resin according to the present invention comprises the steps of: (1) preparing a rubber latex for producing a rubber latex from a conjugated diene monomer using a reactive emulsifier; (2) a resin latex preparation step of graft copolymerizing the (meth) acrylic acid monomer, the aromatic vinyl monomer and the vinyl cyan monomer to the rubber latex to prepare a resin latex; (3) agglomerating the resin latex to obtain a wet powder; And (4) wet co-extruding the wet powder together with the aromatic vinyl-based copolymer to produce pellets.

A method for producing a transparent thermoplastic resin according to the present invention comprises the steps of: (1) preparing a rubber latex by using 1.0 to 1.5 parts by weight of a reactive emulsifier based on 100 parts by weight of a conjugated diene monomer; (2) 25 to 45% by weight of a (meth) acrylic acid monomer, 7 to 17% by weight of an aromatic vinyl monomer, 1 to 8% by weight of a vinyl cyan monomer, 0.1 to 0.5% by weight of a reactive emulsifier % Of an initiator and 0.1 to 0.5% by weight of an initiator to prepare a resin latex of a graft copolymer; (3) agglomerating the resin latex to obtain a wet powder; And (4) a wet co-extrusion step of wet-co-extruding the wet powder together with the aromatic vinyl-based copolymer, and wet-pneumatically extruding the wet powder so that the rubber content of the final resin is within a range of 10 to 30 wt%.

Examples of the reactive emulsifier include anionic and neutral polymer emulsifiers having an allyl group, anionic and neutral polymer emulsifiers having a (meth) acryloyl group, anionic or neutral polymer emulsifiers having a propenyl group, A reactive emulsifier selected from the group consisting of a mixture of two or more can be used.

In the step of preparing the rubber latex, the gel content adjusting agent may be further contained in an amount within a range of 0.1 to 1.0 part by weight.

The gel content regulator may be selected from the group consisting of ethyl-2-mercaptoethylpropionate, 2-mercaptoethylpropionate, 2-mercaptoethanol, mercaptoacetic acid, n-octylmercaptane, n-dodecylmercaptan, t- Dodecyl mercaptan, and mixtures of two or more thereof.

The conjugated diene monomer may be selected from the group consisting of 1,3-butadiene, isoprene, chloroprene, pyrylene, and mixtures of two or more thereof.

The rubber latex may have a swelling index of 5 to 25 or less.

The rubber latex may have an average particle size within a range of 2500 to 3800 ANGSTROM.

The rubber latex may have a gel content within the range of 75 to 95%.

The step of preparing the resin latex may further include 0.05 to 0.5% by weight of a molecular weight regulator.

The molecular weight regulator used in the resin latex preparation step may be selected from the group consisting of ethyl-2-mercaptoethylpropionate, 2-mercaptoethylpropionate, 2-mercaptoethanol, mercaptoacetic acid, n-octylmercaptan, n- Dodecyl mercaptan, t-dodecyl mercaptan, and mixtures of two or more thereof.

The (meth) acrylic acid monomer used in the resin latex preparation step may be selected from the group consisting of an alkyl acrylate, an alkyl methacrylate, or a mixture thereof.

The (meth) acrylic acid monomer used in the resin latex preparation step may be at least one selected from the group consisting of acrylic acid methyl ester, methacrylic acid methyl ester, acrylic acid ethyl ester, methacrylic acid ethyl ester, acrylic acid propyl ester, methacrylic acid propyl ester, , 2-ethylhexyl methacrylate ester, decyl acrylate, decyl methacrylate, lauryl acrylate, lauryl methacrylate, and mixtures of two or more thereof.

The aromatic vinyl monomers used in the resin latex preparation step may be selected from the group consisting of styrene, alpha-methyl styrene, p-methyl styrene, vinyl toluene, t-butyl styrene ), Chlorostyrene, a substituent thereof, and a mixture of two or more thereof.

The vinyl cyan monomer used in the resin latex preparation step may be selected from the group consisting of acrylonitrile, methacrylonitrile, a substituent thereof, and a mixture of two or more thereof.

The initiator used in the resin latex preparation step may be selected from the group consisting of cumene hydroperoxide, diisopropylbenzene hydroperoxide, t-butyl hydroperoxide, p-methane hydroperoxide, benzoyl peroxide as the oil soluble peroxide initiator; Metal salts selected from the group consisting of iron (II), iron (III), cobalt (II) or cerium (IV) and mixtures of two or more thereof as the oxidation-reduction type polymerization initiator and deoxides, A reducing agent selected from the group consisting of glucose, proctose, dihydroxyacetone, polyamine or a mixture of two or more thereof.

The molecular weight of the resin latex may be in the range of 50,000 to 150,000 as the weight average molecular weight.

In the flocculating step, the wet powder may be dehydrated to have a water content within the range of 25 to 30%.

The aromatic vinyl-based copolymer may be obtained by copolymerizing 40 to 80% by weight of a (meth) acrylic acid monomer, 10 to 50% by weight of an aromatic vinyl monomer, and 1 to 30% by weight of a vinyl cyan monomer.

There is no difference in refractive index between the graft copolymer and the aromatic vinyl-based copolymer or may be less than 0.005.

The refractive index of the graft copolymer and the aromatic vinyl-based copolymer may be in the range of 1.510 to 1.526.

The wet co-extrusion may be performed by co-extruding the wet powder of the resin latex and the aromatic vinyl-based copolymer while reducing the pressure in the co-extruder to a pressure of atmospheric pressure or less.

The wet co-extrusion is carried out by injecting the wet powder of the resin latex into the co-extruder and then injecting the aromatic vinyl copolymer into the co-extruder, wherein the pressure in the co-extruder before and after the addition of the aromatic vinyl- Extruding the wet powder of the resin latex and the aromatic vinyl-based copolymer while vacuum-depressurizing the resin latex at a pressure lower than the atmospheric pressure.

The thermoplastic resin produced according to the process for producing a transparent thermoplastic resin without mold precipitation according to the present invention can be produced by co-extruding a reactive emulsifier instead of a commonly used fat emulsifier and wet co- And is advantageous in that mold precipitation can be prevented during high-speed continuous injection molding.

Hereinafter, the present invention will be described in more detail.

A process for producing a transparent thermoplastic resin according to the present invention comprises the steps of: (1) preparing a rubber latex for producing a rubber latex from a conjugated diene monomer using a reactive emulsifier; (2) a resin latex preparation step of graft copolymerizing the (meth) acrylic acid monomer, the aromatic vinyl monomer and the vinyl cyan monomer to the rubber latex to prepare a resin latex; (3) agglomerating the resin latex to obtain a wet powder; And (4) wet co-extruding the wet powder together with the aromatic vinyl-based copolymer to produce pellets. That is, the present invention relates to a process for producing a graft copolymer having a high rubber content by controlling the refractive index by emulsion polymerization to obtain transparency, a process for preparing an aromatic vinyl copolymer resin having a controlled refractive index by solution polymerization, And a step of kneading.

More particularly, the process for producing a transparent thermoplastic resin according to the present invention comprises the steps of: (1) preparing a rubber latex by using 1.0 to 1.5 parts by weight of a reactive emulsifier based on 100 parts by weight of a conjugated diene monomer; (2) 25 to 45% by weight of a (meth) acrylic acid monomer, 7 to 17% by weight of an aromatic vinyl monomer, 1 to 8% by weight of a vinyl cyan monomer, 0.1 to 0.5% by weight of a reactive emulsifier % Of an initiator and 0.1 to 0.5% by weight of an initiator to prepare a resin latex of a graft copolymer; (3) agglomerating the resin latex to obtain a wet powder; And (4) wet co-extruding the wet powder together with the aromatic vinyl-based copolymer in a wet co-extruding step such that the rubber content of the final resin is within a range of 10 to 30% by weight .

Examples of the reactive emulsifier include anionic and neutral polymer emulsifiers having an allyl group, anionic and neutral polymer emulsifiers having a (meth) acryloyl group, anionic or neutral polymer emulsifiers having a propenyl group, A reactive emulsifier selected from the group consisting of a mixture of two or more can be used. The reactive emulsifier in the present invention means an emulsifier capable of chemically bonding in polymerization.

Examples of the anionic emulsifier having an allyl group include a sulfate salt of polyoxyethylene allylglycidylnonylphenyl ether. Examples of the neutral emulsifier having an allyl group include polyoxyethylene allylglycidylnonylphenyl ether and the like. The sulfate salt of the polyoxyethylene allylglycidylnonylphenyl ether may be ADEKARIA SOAP SE, trade name of Asahi Denka, Japan. The polyoxyethylene allyl glycidyl nonyl phenyl ether may be ADEKARIA SOAP NE, trade name of Asahi Denka Co., Ltd., Japan.

An anionic emulsifier having a (meth) acryloyl group is available on the market from ELEMINOL RS, a product name of Sanyo Kasei, Japan and Nippon Surfactant of Japan, Trade name RMA-560. Polymer type emulsifiers include UM and UX of Toagosei, Japan. Examples of anionic emulsifiers having a propenyl group include ammonium sulfate salts of polyoxyethylene allyl glycidylnonyl propylphenyl ether. Daiichi Kogyo Seiyaku, a product of Japan, And AQUARON BC, a product name of Kao Corporation, Japan, and LATEMUL, a product name of kao in Japan. The neutral emulsifier is AQUARON BC, a product of Daiichi Kyoei Iyakusa, Japan. The reactive emulsifier is preferably an anionic emulsifier. Neutral emulsifiers have a disadvantage in that they generate less solid particles and have a longer reaction time and lower latex stability than anionic emulsifiers. These reactive emulsifiers may be used alone or as a mixture of two or more thereof.

Examples of the reactive emulsifier include sulfoethyl methacrylate (SEM), 2-acrylamido-2-methylpropane sulfonic acid (AMPS), sodium styrenesulfonate Sodium styrene sulfonate (NaSS), sodium dodecyl allyl sulfosuccinate (trade name: TREM LF-40), copolymer of styrene and sodium dodecyl allylsulfosuccinate, polyoxyethylene alkylphenyl ether ammonium sulfate HITENOL-BC, HITENOL-KH, C16-18 alkenyl succinic acid di-potassium salt having a carbon number of 16 to 18 (trade name Latemul ASK, ELOPLA AS100 series), methallyl sulphate Sodium methallyl sulfonate (SMAS), and mixtures of two or more thereof.

In the preparation of the rubber latex, the reactive emulsifier may be used in an amount of 1.0 to 1.5 parts by weight, preferably 1.1 to 1.4 parts by weight, more preferably 1.2 to 1.3 parts by weight, based on 100 parts by weight of the conjugated diene monomer , The use of the reactive emulsifier within this range is suitable for obtaining a thermoplastic resin free from mold precipitation.

In the preparation of the rubber latex, 50 parts by weight to 100 parts by weight of the conjugated diene monomer are added to 100 parts by weight of the conjugated diene monomer and polymerized for 5 to 15 hours, and then the remaining conjugated diene monomers are collectively administered or sequentially administered For 10 to 20 hours. At this time, the total amount of the reactive emulsifier is preferably 2.0 parts by weight or less by increasing the stability of the rubber latex by charging the reactive emulsifier at the beginning of the reaction. At this time, the reactive emulsifier is preferably an anionic reactive emulsifier. When the conjugated diene monomer is added in the middle, the reactive emulsifier may be mixed with the emulsifier alone or a non-reactive emulsifier. The rubber latex thus produced can minimize the amount of residual impurities, and thus, when the ABS resin is applied, a rubber latex having excellent thermal stability and no mold precipitation can be obtained.

In the step of preparing the rubber latex, a gel content regulator is added in an amount within a range of 0.1 to 1.0 part by weight, preferably 0.1 to 0.6 part by weight, more preferably 0.2 to 0.4 part by weight, based on 100 parts by weight of the conjugated diene monomer It is preferable to obtain a rubber latex having an average particle diameter of 2500 to 3800A and a gel content within a range of 70 to 95%. The gel content adjusting agent is preferably mercaptans, and is preferably a volatile ethyl 2-mercaptoethylpropionate, 2-mercaptoethylpropionate, 2-mercaptoethanol, mercaptoacetic acid, n-octylmercaptan , n-dodecyl mercaptan, t-dodecyl mercaptan and mixtures of two or more thereof.

The conjugated diene monomer may be selected from the group consisting of 1,3-butadiene, isoprene, chloroprene, pyrylene, and mixtures of two or more thereof. The conjugated diene monomer may be used together with an ethylenically unsaturated monomer, and the ethylenically unsaturated monomer is preferably an aromatic vinyl monomer, a vinyl cyan monomer, and a mixture thereof, which are used in the production of a resin latex of a graft copolymer described later . ≪ / RTI >

The production of the rubber latex will be described in detail as follows.

The present invention relates to a method for producing a polymer electrolyte membrane, which comprises 50 to 100 parts by weight of a conjugated diene monomer in an amount of 50 to 100 parts by weight, 1.0 to 1.5 parts by weight of a reactive emulsifier, 0.1 to 0.6 parts by weight of a polymerization initiator, 0.2 to 1.0 part by weight of an electrolyte, And 75 to 100 parts by weight of water to be exchanged at a temperature of 65 to 75 DEG C for 5 to 15 hours, and then 0.1 to 0.5 parts by weight of the remaining conjugated diene monomer and the reactive emulsifier and 0.05 to 0.5 parts by weight of the molecular weight modifier are collectively administered Or sequentially and at a temperature of 70 to 85 ° C for 10 to 20 hours to improve the stability of the latex so that the amount of the emulsifier used does not exceed 2.0 parts by weight so that the thermoplastic resin excellent in thermal stability and free of mold precipitation can be produced Can be provided.

Examples of the polymerization initiator used in the rubber latex preparation step include cumene hydroperoxide, diisopropylbenzene hydroperoxide, tert-butyl hydroperoxide, p-methane hydroperoxide, benzoyl peroxide, and the like as oil soluble peroxide initiators; Metal salts selected from the group consisting of iron (II), iron (III), cobalt (II) or cerium (IV) and mixtures of two or more thereof as the oxidation-reduction type polymerization initiator and deoxides, A reducing agent selected from the group consisting of glucose, proctose, dihydroxyacetone, polyamine or a mixture of two or more thereof. Water-soluble initiators such as persulfates may be used.

The electrolyte can be selected from the group consisting of potassium chloride (KCl), sodium chloride (NaCl), potassium hydrogencarbonate (KHCO ₃ ), sodium hydrogen carbonate (NaHCO ₃ ), sodium carbonate (Na ₂ CO ₃ ), potassium carbonate (K ₂ CO ₃ ) KHSO _3), sodium bisulfate (NaHSO _3), potassium pyrophosphate _{(K 4 P 2 O 7)} , sodium pyrophosphate _{(Na 4 P 2 O 7)} , potassium phosphate (K ₃ PO _4), sodium phosphate (Na ₃ PO ₄ ), sodium monohydrogenphosphate (Na ₂ HPO ₄ ) and potassium monohydrogenphosphate (K ₂ HPO ₄ ).

The rubber latex may have a swelling index of 25 or less.

The rubber latex may have an average particle size within a range of 2500 to 3800 ANGSTROM.

The rubber latex may have a gel content within the range of 70 to 95%.

In the present invention, the properties and properties of the rubber latex can be measured by the following method.

1) Gel content and swelling index

The resulting rubber latex was coagulated with dilute acid or metal salt, washed and dried in a vacuum oven at 60 DEG C for 24 hours. The resulting rubber mass was finely cut with scissors, and 1 g of the rubber piece was placed in 100 g of toluene for 48 hours The gel content and the swelling index are measured by the following equations (1) and (2).

[Equation 1]

Gel content (%) = (weight of insoluble matter (gel) / weight of sample) * 100

&Quot; (2) "

Swelling index = weight of swollen gel / weight of gel

2) Particle size and particle size distribution

Dynamic Light Scattering (DLS) using laser light as a light source was measured using Nicomp 370HPL, a particle sizing system manufactured by Particle Sizing Systems, United States of America.

Generated coagulum = production of coagulated coagulum / weight of total monomers administered * 100

In addition, the resin latex can be produced as follows.

(I) 25 to 45% by weight of a (meth) acrylic acid monomer, iii) an aromatic (meth) acrylic acid monomer composition comprising i) 40 to 60% by weight of a rubber latex having a particle size of 2500 to 3800 ANGSTROM and a gel content of 70 to 95% 7 to 17% by weight of a vinyl monomer; iv) from 1 to 8% by weight of a vinyl cyan monomer; v) 0.1 to 0.5% by weight of a reactive emulsifier; vi) 0.1 to 1.0% by weight of a molecular weight regulator; And vi) 0.1 to 0.5% by weight of a polymerization initiator is graft copolymerized.

Examples of the (meth) acrylic acid monomer of ii) include acrylic acid esters such as (meth) acrylic acid methyl ester, (meth) acrylic ester, (meth) acrylic acid propyl ester, (meth) acrylic acid 2-ethylhexyl ester, ) Acrylic acid lauryl ester and similar compounds may be used alone or in combination of two or more.

As the aromatic vinyl compound of iii), styrene,? -Methylstyrene, p-methylstyrene, vinyltoluene, t-butylstyrene, chlorostyrene or their substituents may be used alone or in combination of two or more.

As the vinyl cyan compound of iv), acrylonitrile, methacrylonitrile, or their substituents may be used alone or in combination of two or more.

The reactive emulsifier of v) may be used in an amount of 0.1 to 0.5% by weight, examples of which are the same as or similar to those described above, and repeated descriptions are avoided.

As the molecular weight regulator (vi), mercaptans are preferable, and ethyl 2-mercaptoethylpropionate, 2-mercaptoethylpropionate, 2-mercaptoethanol and mercaptoacetic acid having excellent volatility are dissolved in n- N-dodecylmercaptan, t-dodecylmercaptan and the like can be used alone or in admixture of two or more, and the amount of use is preferably 0.1 to 1.0% by weight.

The above-mentioned vi) polymerization initiator may be selected from polymerization initiators such as cumene hydroperoxide, diisopropylbenzene hydroperoxide, tertiary butyl hydroperoxide, paramethane hydroperoxide or benzoyl peroxide, and oxidation-reduction polymerization Initiators can be used together, and the amount to be used is preferably 0.1 to 0.5% by weight. Examples of the redox polymerization initiator include metal salts such as iron (II), iron (III), cobalt (II), or cerium (IV); reducing agents include dehydroxyacetone or polysaccharide such as dextrose, glucose, Amines and the like can be used.

In general, the monomer mixture during graft copolymerization may be used in a continuous or batchwise manner or in a batchwise manner, and is not particularly limited. Preferably, 5 to 40% of the total monomer mixture is used in the initial stage of the reaction It is preferable to batchwise add the remaining monomer mixture continuously.

The graft polymerization reaction time is preferably within 4 hours, the polymerization conversion rate after the reaction is 98.5 or more, and the molecular weight of the polymer is preferably 50,000 to 150,000 in weight average molecular weight.

The refractive index of the monomer mixture used in the preparation of the graft copolymer has an absolute influence on the transparency of the desired resin, and the refractive index can be controlled by the amount of the monomer and the mixing ratio. That is, in order to have transparency, the refractive index of the conjugated diene rubber latex used in the production of the graft copolymer should be similar to that of the entire monomer component grafted to the excitation, and the refractive index of the conjugated diene rubber latex should be similar to that of the conjugated diene rubber latex. It is preferable that the refractive indexes of the entire monomer components grafted to the graft copolymer are coincident with each other. The refractive index after polymerization of each component used in the production of the graft copolymer is about 1.518 for butadiene, about 1.490 for methacrylate alkyl ester, about 1.590 for styrene and about 1.518 for acrylonitrile, and the refractive index The resin of the copolymer can have a refractive index of about 1.518.

The stability of the prepared graft copolymer latex was determined by measuring the solidification percentage (%) as shown in the following equation (3).

&Quot; (3) "

Solid solid content (%) = {weight (g) of formed solidified product in the reaction tank / weight (g) of total rubber and monomer) x 100

When the solidified solid content is 0.5% or more, the latex stability is extremely low and it is difficult to obtain a graft polymer suitable for the present invention due to a large amount of solidified material.

The graft ratio of the graft polymer is measured as follows.

The graft polymer latex is solidified, washed, and dried to obtain a powder form. 2 g of the powder is added to 300 ml of acetone and stirred for 24 hours. After separating the solution using an ultracentrifuge, the separated acetone solution is dropped into methanol to obtain a non-grafted portion, which is then dried and weighed. From these weights, the graft rate is calculated according to the following equation (4).

&Quot; (4) "

Graft rate (%) = weight of grafted monomer (g) / rubber weight (g) x 100

At this time, if the graft ratio is 20% or less, the gloss is lowered, which is not preferable.

The graft copolymer latex prepared as described above may further contain an antioxidant to prevent oxidation during processing. The antioxidant may be a conventionally used phenolic antioxidant, phosphorus-based or sulfur-based antioxidant, and may be used in an amount of 0.1 to 2 parts by weight per 100 parts by weight of the graft copolymer latex emulsified with a particle diameter of 0.5 to 2 μm . The antioxidant is preferably slowly added to the graft copolymer latex at 40 to 80 ° C and stirred continuously until the agglomeration process.

The agglomeration method of the graft copolymer latex prepared as described above includes a step of adding a metal salt or an acid to the graft copolymer latex and aging the graft copolymer latex. Examples of the agglomerating agent include magnesium sulfate (MgSO ₄ ), calcium chloride (CaCl ₂ ) this, aluminum sulfate _{(Al 2 (SO 4) 3} ), sulfuric acid, phosphoric acid, or hydrochloric acid, and the like.

In addition, the resin latex may further contain 0.1 to 1.0% by weight, preferably 0.2 to 0.5% by weight, and most preferably 0.25 to 0.3% by weight based on the total weight of the reaction mixture, , And it is preferable to use a molecular weight modifier within this range.

The molecular weight regulator used in the resin latex preparation step may be selected from the group consisting of ethyl-2-mercaptoethylpropionate, 2-mercaptoethylpropionate, 2-mercaptoethanol, mercaptoacetic acid, n-octylmercaptan, n- Dodecyl mercaptan, t-dodecyl mercaptan, and mixtures of two or more thereof.

The (meth) acrylic acid monomer used in the resin latex preparation step may be selected from the group consisting of alkyl acrylates, alkyl methacrylates, and mixtures thereof, preferably methyl acrylate, methyl methacrylate Acrylic acid esters, acrylic acid ethyl ester, methacrylic acid ethyl ester, acrylic acid propyl ester, methacrylic acid propyl ester, acrylic acid 2-hexyl ester, methacrylic acid 2-ethylhexyl ester, acrylic acid decyl ester, methacrylic acid decyl ester, Esters, methacrylic acid lauryl esters, and mixtures of two or more thereof.

The aromatic vinyl monomers used in the resin latex preparation step may be selected from the group consisting of styrene, alpha-methyl styrene, p-methyl styrene, vinyl toluene, t-butyl styrene ), Chlorostyrene, a substituent thereof, and a mixture of two or more thereof.

The vinyl cyan monomer used in the resin latex preparation step may be selected from the group consisting of acrylonitrile, methacrylonitrile, a substituent thereof, and a mixture of two or more thereof.

The reactive emulsifier used in the resin latex preparation step may be selected from the group consisting of sulfoethyl methacrylate (SEM), 2-acrylamido-2-methylpropane sulfonic acid (AMPS) , Sodium styrene sulfonate (NaSS), sodium dodecyl allyl sulfosuccinate (TREM LF-40), copolymers of styrene and sodium dodecyl allylsulfosuccinate, polyoxyethylene alkyl HITENOL-BC, HITENOL-KH, C16-18 alkenyl succinic acid di-potassium salt (trade name: Latemul ASK, ELOPLA AS100) having a carbon number of 16 to 18, polyoxyethylene alkylphenyl ether ammonium sulfate , Sodium methallyl sulfonate (SMAS), and mixtures of two or more thereof. The reactive emulsifier may be selected from the group consisting of It is preferably used in an amount within a range of 0.1 to 0.5% by weight, preferably 0.1 to 0.4% by weight, and most preferably 0.2 to 0.3% by weight, based on the total weight of the reaction mixture.

The initiator used in the resin latex preparation step may be selected from the group consisting of cumene hydroperoxide, diisopropylbenzene hydroperoxide, t-butyl hydroperoxide, p-methane hydroperoxide, benzoyl peroxide as the oil soluble peroxide initiator; Metal salts selected from the group consisting of iron (II), iron (III), cobalt (II) or cerium (IV) and mixtures of two or more thereof as the oxidation-reduction type polymerization initiator and deoxides, A reducing agent selected from the group consisting of glucose, proctose , dihydroxyacetone, polyamine or a mixture of two or more thereof. The initiator is preferably used in an amount of 0.1 to 0.5% by weight, preferably 0.2 to 0.4% by weight, most preferably 0.3 to 0.4% by weight, based on the total weight of the reaction mixture.

The resin latex agglomerated as described above can be obtained by dewatering to a wet powder having a moisture content of 25 to 30%, preferably 26 to 30%, more preferably 27 to 29%. The dewatering described above can be carried out by mechanically pressing, preferably by dehydrating with a centrifugal dehydrator.

Thereafter, the wet powder may be wet co-extruded together with the aromatic vinyl-based copolymer, thereby being made into pellets.

The aromatic vinyl-based copolymer is a copolymer of a (meth) acrylic acid monomer, an aromatic vinyl monomer and a vinyl cyan monomer, preferably a methyl methacrylate-styrene-acrylonitrile copolymer (hereinafter referred to as "MSAN" (Meth) acrylic acid monomer in an amount of 10 to 50% by weight, an aromatic vinyl monomer in an amount of 1 to 30% by weight and a vinyl cyan monomer in an amount of 40 to 80% by weight.

The aromatic vinyl-based copolymer obtained according to the above was prepared by polymerizing (meth) acrylic monomers having a refractive index of about 1.490, styrene having a refractive index of about 1.590 and acrylonitriles having a refractive index of about 1.518, The refractive index of the aromatic vinyl-based copolymer obtained from the aromatic vinyl-based copolymer may be the same as or less than 0.005 of the refractive index of the graft copolymer resin, and the refractive index difference may be very small. It is possible to manufacture a highly transparent thermoplastic resin.

The aromatic vinyl copolymer is prepared by mixing 100% by weight of a monomer mixture prepared by mixing 40 to 80% by weight of a (meth) acrylic acid monomer, 10 to 50% by weight of an aromatic vinyl monomer and 1 to 30% by weight of a vinyl cyan monomer, 10 to 50% by weight, preferably 20 to 40% by weight, more preferably 25 to 35% by weight, especially 30% by weight, as initiator 1,1-bis (t-butylperoxy) 0.001 to 0.1% by weight, preferably 0.01 to 0.05% by weight, more preferably 0.015 to 0.03% by weight, especially 0.02% by weight, of trimethylcyclohexane and 0.05 to 0.3% by weight of tertiary-dodecylmercaptan as a molecular weight modifier, , Preferably 0.1 to 0.2 wt.%, More preferably 0.12 to 0.18 wt.%, Particularly 0.15 wt.% Of the raw materials are continuously introduced into the reactor so that the average reaction time is 2 to 4 hours, especially 3 hours The reaction temperature is 130 to 160 DEG C, But preferably maintained at 140 to 155 占 폚, especially 148 占 폚. Thereafter, the polymerized solution is discharged from the reaction tank, the discharged polymerized solution is heated in a preheating tank, the unreacted monomers are volatilized in the volatilization tank, and the temperature of the polymer is adjusted to 180 to 240 ° C, preferably 190 to 230 ° C, More preferably 200 to 220 占 폚, especially 210 占 폚, by using a polymer transfer pump extrusion machine to obtain an MSAN copolymer resin in the form of pellets. The refractive index of the MSAN copolymer resin thus prepared was about 1.518, which is particularly suitable for use in the present invention because the oligomer content is lower than that of the heat-polymerized MSAN copolymer resin without an initiator.

The mixing ratio of the mixture of the wet powder and the aromatic vinyl-based copolymer is preferably such that the final rubber content in the final resin is within a range of 10 to 30% by weight so that the wet powder is evaporated with the aromatic vinyl- , The transparent thermoplastic resin according to the present invention is preferably obtained in the form of pellets by a wet co-extrusion method as extrusion kneading.

In the present invention, wet coextrusion is applied in the extrusion process to evaporate water when a vacuum is applied during extrusion processing, and unreacted monomers and oligomers are volatilized together to minimize thermal stability and material causing mold precipitation, Thereby making it possible to manufacture a transparent thermoplastic resin in which mold precipitation does not occur.

The mixture of the wet powder and the aromatic vinyl-based copolymer powder is preferably added with additives such as a lubricant and a heat stabilizer, and then subjected to wet co-extrusion as an extrusion kneading process including a water evaporation process in an extruder at 200 to 250 ° C Lt; RTI ID = 0.0 > co-extruded. ≪ / RTI >

That is, the wet co-extrusion may be performed by co-extruding the wet powder of the resin latex and the aromatic vinyl copolymer while vacuum-depressurizing the pressure in the co-extruder to atmospheric pressure (760 torr) or less, Extruding is carried out by injecting the wet powder of the resin latex into the co-extruder and then injecting the aromatic vinyl copolymer into the co-extruder, wherein the pressure in the co-extruder before and after the introduction of the aromatic vinyl- And then co-extruding the wet powder of the resin latex and the aromatic vinyl-based copolymer while vacuum-reducing the pressure.

The mixture of the wet powder and the aromatic vinyl-based copolymer is preferably added with additives such as a lubricant and a heat stabilizer, and then subjected to wet co-extrusion as extrusion kneading in an extruder at 200 to 250 DEG C, Lt; / RTI >

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope and spirit of the invention as disclosed in the accompanying claims. Changes and modifications may fall within the scope of the appended claims.

[Example]

Example 1

(1) Production of rubbery latex

75 parts by weight of ion-exchanged water, 100 parts by weight of 1,3-butadiene as a monomer, 1.5 parts by weight of potassium salt of alkenylsuccinic acid dicarboxylic acid having 16 to 18 carbon atoms as a reactive emulsifier (ELOPLA AS100) , 2.0 parts by weight of potassium carbonate (K ₂ CO ₃ ) as an electrolyte, 0.3 part by weight of tertiary dodecyl mercaptan (TDDM) as a molecular weight regulator and 0.2 part by weight of potassium persulfate as an initiator, Lt; / RTI > When the polymerization conversion rate of the reaction product was 50%, 0.05% by weight of tert-dodecylmercaptan was added to the reaction mixture at a temperature of 75 ° C for 20 hours, and when the polymerization conversion reached 90%, the polymerization inhibitor was added and the reaction was terminated . The rubber latex thus obtained was analyzed. The obtained rubber latex had an average particle diameter of about 3100 Å and a gel content of about 85%.

(2) Preparation of Resin Latex of Graft Copolymer

50 parts by weight of a polybutadiene rubber latex having an average particle size of rubber latex of 3100 Å and a gel content of 85%, 100 parts by weight of ion-exchanged water, 100 parts by weight of ion-exchanged water, and 100 parts by weight of Daiich 0.3 part by weight of HITENOL HS-10 ™ manufactured by Kogyo Seiyaku, 54 parts by weight of methacrylate alkyl ester, 21 parts by weight of styrene, 5 parts by weight of acrylonitrile, 0.5 part by weight of tertiary dodecylmercaptan, , 0.024 part by weight of dextrose, 0.002 part by weight of iron sulfate, and 0.08 part by weight of cumene hydroperoxide were successively administered at 75 DEG C for 5 hours and reacted. After the reaction, the temperature was raised to 80 DEG C, aged for 1 hour, and the reaction was terminated. The polymerization conversion was 99%, the solid solid content was 0.2%, and the solid content was 50%. Then, the latex was treated with an antioxidant and a stabilizer to coagulate with an aqueous solution of calcium chloride, washed, and then a graft copolymer having a water content of 28% was obtained. The refractive index of the obtained graft copolymer was 1.518.

(3) Production process of styrene-based copolymer resin (MSAN)

63% by weight of methacrylate methyl ester, 24.6% by weight of styrene and 12% by weight of acrylonitrile were mixed to prepare 100% by weight of a monomer mixture, and 30% by weight of toluene was used as a solvent based on the total weight of the monomer mixture, 0.02% by weight of bis (t-butylperoxy) -3,3,5-trimethylcyclohexane and 0.15% by weight of tertiary dodecyl mercaptan as a molecular weight regulator were mixed so that the average reaction time was 3 hours The reaction temperature was maintained at 148 占 폚 while continuously introduced into the reactor. Thereafter, the polymerized solution was discharged from the reaction tank, the discharged polymerized solution was heated to 230 DEG C in a preheating tank, the unreacted monomers were volatilized in a volatilization tank, and the polymer was subjected to extrusion MSA copolymer resin was obtained in the form of pellets using a machine. The refractive index of the prepared MSAN copolymer resin was 1.518.

(4) Wet Powder Extrusion Process

The above obtained MSAN resin as an aromatic vinyl polymer was melt-kneaded in a wet co-extruder at a cylinder temperature of 230 ° C in the form of pellets in an ABS graft copolymer having a water content of 28% Extruded to prepare a specimen having a final rubber content of 15%, and the properties thereof were measured.

The physical properties of the pellets were measured by re-injection of the pellets.

In the physical property measurement, the haze was measured according to ASTM 1003, the impact strength (Izod impact strength) was measured according to ASTM D256, and the melt index was measured according to ASTM D1238.

In addition, the mold settling was repeated 50 times during injection molding at 250 DEG C, and the material on the surface of the mold was collected and analyzed by gas generation during continuous injection. The mold settling substance was analyzed using the molds used in the production of the graft copolymer Molecular weight fat emulsifiers and residual oligomers in the MSAN polymer.

Thermal stability was evaluated by injection residence test (residence at 250 ° C for 15 minutes at injection).

The measured physical properties are shown in Table 1.

Example 2

Except that 0.3 wt% of HITENOL KH-10, a product of Daiichi Kogyo Seiyakusa, Japan, was continuously injected for 2 hours as a reactive emulsifier in the production of graft copolymer.

Example 3

Except that 0.3% by weight of sodium dodecyl allyl sulfosuccinate (trade name: TREM LF-40) was continuously injected as a reactive emulsifier for 2 hours in the preparation of the graft copolymer. Respectively.

Comparative Example 1

2.0% by weight of a fatty acid soap (Fatty emulsifier) was used instead of the reactive emulsifier in the preparation of the graft copolymer, and 0.4% by weight of tertiary dodecylmercaptan was used as the molecular weight modifier for 3 hours. 1. ≪ / RTI >

The measured physical properties are shown in Table 2.

The measured physical properties are shown in Table 2.

Comparative Example 2

The styrenic copolymer resin was dewatered to a water content of about 28% using a centrifugal dehydrator and dried in a drier to prepare a styrenic copolymer resin in the form of a dry powder having a water content of 0.8% The procedure of Example 1 was repeated except that extrusion kneading was performed using a general twin-screw extruder.

The measured physical properties are shown in Table 2.

Example 1 Example 2 Example 3 Graft rate (%) 43 42 41 Mold settling
(Visual determination) Very good Very good Very good Transparency (haze) (%) 1.5 1.6 1.4 Impact strength
(Kg · cm / cm) 14 13 13 Flowability (MFR)
(g / 10 min) 25 26 26 Stagnation of color difference
(ΔE) <2.0 <2.0 <2.0

Comparative Example 1 Comparative Example 2 Graft rate (%) 45 - Mold settling
(Visual determination) usually usually Transparency (haze) (%) 2.9 3.9 Impact strength
(Kg · cm / cm) 13 15 Flowability (MFR)
(g / 10 min) 26 27 Stagnation of color difference
(ΔE) 5.0 5.0

As a result of the evaluation, as shown in Tables 1 and 2, an excellent thermoplastic resin which is the same or similar in physical properties such as graft rate, impact strength and fluidity, and which is particularly excellent in transparency and color difference of staying color, It can be confirmed that it can be obtained.

Claims (23)

(1) a step of producing a rubber latex for producing a rubber latex from a conjugated diene monomer using a reactive emulsifier;
(2) a resin latex preparation step of graft copolymerizing the (meth) acrylic acid monomer, the aromatic vinyl monomer and the vinyl cyan monomer to the rubber latex to prepare a resin latex;
(3) agglomerating the resin latex to obtain a wet powder; And
(4) a wet co-extrusion step of wet-co-extruding the wet powder together with the aromatic vinyl-based copolymer to produce pellets,
Wherein the wet powder has a water content of 25 to 30% by weight. (1) preparing a rubber latex by using 1.0 to 1.5 parts by weight of a reactive emulsifier based on 100 parts by weight of a conjugated diene monomer;
(2) 25 to 45% by weight of a (meth) acrylic acid monomer, 7 to 17% by weight of an aromatic vinyl monomer, 1 to 8% by weight of a vinyl cyan monomer, 0.1 to 0.5% by weight of a reactive emulsifier % Of an initiator and 0.1 to 0.5% by weight of an initiator to prepare a resin latex of a graft copolymer;
(3) agglomerating the resin latex to obtain a wet powder; And
(4) a wet co-extrusion step of wet-co-extruding the wet powder together with the aromatic vinyl-based copolymer, wherein the wet powder is wet-pneumatically extruded so that the rubber content of the final resin is within a range of 10 to 30% by weight;
Wherein the transparent thermoplastic resin is a thermoplastic resin. 3. The method of claim 2,
In the rubber latex preparation step, anionic and neutral polymer emulsifiers having an allyl group as the reactive emulsifier, anionic and neutral polymer emulsifiers having a (meth) acryloyl group, anionic or neutral polymers having a propenyl group And a reactive emulsifier selected from the group consisting of a mixture of two or more thereof. 3. The method of claim 2,
Wherein the gel content adjusting agent is further contained in an amount within a range of 0.1 to 1.0 part by weight in the step of preparing the rubber latex. 5. The method of claim 4,
Wherein the gel content regulating agent is selected from the group consisting of ethyl-2-mercaptoethylpropionate, 2-mercaptoethylpropionate, 2-mercaptoethanol, mercaptoacetic acid, n-octylmercaptane, n-dodecylmercaptan, t- Dodecyl mercaptan, and dodecyl mercaptan, and mixtures of two or more thereof. 3. The method of claim 2,
Wherein the conjugated diene monomer is selected from the group consisting of 1,3-butadiene, isoprene, chloroprene, p-terylene, and a mixture of two or more thereof. 3. The method of claim 2,
Wherein the rubber latex has a swelling index of 25 or less. 3. The method of claim 2,
Wherein the rubber latex has an average particle size within a range of 2500 to 3800 ANGSTROM. 3. The method of claim 2,
Wherein the rubber latex has a gel content within a range of 75 to 95%. 3. The method of claim 2,
Wherein the resin latex further comprises 0.05 to 0.5% by weight of a molecular weight modifier in the step of preparing the resin latex. 11. The method of claim 10,
Wherein the molecular weight regulator used in the resin latex preparation step is selected from the group consisting of ethyl-2-mercaptoethylpropionate, 2-mercaptoethylpropionate, 2-mercaptoethanol, mercaptoacetic acid, n-octylmercaptan, n- Dodecyl mercaptan, t-dodecyl mercaptan, and a mixture of two or more thereof. 3. The method of claim 2,
Wherein the (meth) acrylic acid monomer used in the step of producing the resin latex is selected from the group consisting of alkyl acrylates, alkyl methacrylates, and mixtures thereof. 13. The method of claim 12,
Wherein the (meth) acrylic acid monomer used in the resin latex preparation step is selected from the group consisting of methyl acrylate, methacrylate methyl ester, acrylic acid ethyl ester, methacrylic acid ethyl ester, acrylic acid propyl ester, methacrylic acid propyl ester, acrylic acid 2-hexyl ester Acrylate, lauryl methacrylate, lauryl methacrylate, and a mixture of two or more thereof. The transparent thermoplastic resin composition according to claim 1, wherein the transparent thermoplastic resin is selected from the group consisting of acrylic acid, acrylic acid, methacrylic acid, A method for producing a resin. 3. The method of claim 2,
Wherein the aromatic vinyl monomer used in the resin latex preparation step is selected from the group consisting of styrene, alpha-methyl styrene, p-methyl styrene, vinyl toluene, t-butyl styrene ), Chlorostyrene, a substituent thereof, and a mixture of two or more thereof. 3. The method of claim 2,
Wherein the vinyl cyan monomer used in the step of preparing the resin latex is selected from the group consisting of acrylonitrile, methacrylonitrile, a substituent thereof, and a mixture of two or more thereof. 3. The method of claim 2,
Wherein the reactive emulsifier used in the resin latex preparation step is selected from the group consisting of sulfoethyl methacrylate (SEM), 2-acrylamido-2-methylpropane sulfonic acid (AMPS) , Sodium styrene sulfonate (NaSS), sodium dodecyl allyl sulfosuccinate (trade name TREM LF-40), copolymers of styrene and sodium dodecyl allylsulfosuccinate, polyoxyethylene alkyl Polyoxyethylene alkylphenyl ether ammonium sulfate, C16-18 alkenyl succinic acid di-potassium salt having 16 to 18 carbon atoms, sodium methallyl sulfonate (SMAS) and And a mixture of two or more of them. 17. The method of claim 16,
Wherein said polyoxyethylene alkylphenylether ammonium sulfate is a trade name HITENOL-BC, HITENOL-KH. 17. The method of claim 16,
Wherein the potassium salt of the alkenylsuccinic acid having 16 to 18 carbon atoms is a trade name Latemul ASK or ELOPLA AS100. 3. The method of claim 2,
Wherein the initiator used in the resin latex preparation step is selected from the group consisting of cumene hydroperoxide, diisopropylbenzene hydroperoxide, t-butyl hydroperoxide, p-methane hydroperoxide, benzoyl peroxide as the oil soluble peroxide initiator; Metal salts selected from the group consisting of iron (II), iron (III), cobalt (II) or cerium (IV) and mixtures of two or more thereof as the oxidation-reduction type polymerization initiator and deoxides, Wherein the reducing agent is selected from the group consisting of glucose, proctose, dihydroxyacetone, polyamine or a mixture of two or more thereof. 3. The method of claim 2,
Wherein the molecular weight of the resin latex is within a range of 50,000 to 150,000 as a weight average molecular weight. 3. The method of claim 2,
Wherein the aromatic vinyl-based copolymer is obtained by copolymerizing 10 to 50% by weight of an aromatic vinyl monomer, 1 to 30% by weight of a vinyl cyan monomer, and (meth) acrylic acid monomer as a residual amount. 3. The method of claim 2,
Wherein the refractive index difference between the graft copolymer and the aromatic vinyl copolymer is not less than 0.005 or less. 23. The method of claim 22,
Wherein the refractive index of the graft copolymer and the aromatic vinyl copolymer is in the range of 1.510 to 1.526.