KR100906122B1 - Thermoplastic transparent resin composition and its manufacturing method - Google Patents

Abstract

The present invention relates to a thermoplastic resin and a method for producing the same, and more particularly, to a thermoplastic resin for producing a transparent resin and a method for producing the same.

The thermoplastic resin according to the present invention is a monomer comprising a methacrylic acid alkyl ester, an aromatic vinyl compound and an unsaturated nitrile monomer in a rubber latex mixture (R) made of a diene rubber polymer (R ₁ , R ₂ ) having different particle diameters. The mixture and the emulsifier and dispersant of the alkylaryl sulfonate salt are added and stirred to perform graft polymerization.

The thermoplastic resin according to the present invention can provide a thermoplastic resin excellent in impact resistance and transparency even when mechanically mixed with a PMMA and SAN mixture having good latex stability and good compatibility in manufacturing.

Description

Thermoplastic transparent resin composition and its manufacturing method {TRANSPARENT THERMOPLASTIC RESIN COMPOSITION AND MANUFACTURING MEHTOD THEREOF}

The present invention relates to a thermoplastic resin and a method for producing the same, and more particularly, to a thermoplastic resin for producing a transparent resin and a method for producing the same.

In order to differentiate product models according to various and rapidly changing consumer lives, many studies have been conducted to give high functionality to materials used in the products. In particular, as the need for various colors and gloss as well as impact resistance for mobile phones and home electronics products, research is being focused on giving higher transparency and colorability to materials.

Conventionally, as the transparent resin, polystyrene (hereinafter referred to as PS), styrene-acrylonitrile copolymer (hereinafter referred to as SAN), polymethyl methacrylate (hereinafter referred to as PMMA), etc. are known. It was limited.

As a result, the balance of physical properties such as impact strength and fluidity is well balanced, and acrylic acid alkyl ester or methacrylic acid alkyl ester compound is introduced into the acrylonitrile-butadiene-styrene terpolymer (hereinafter referred to as ABS resin), which has been used in various applications. Many technologies to give transparency have been developed. (US Patent No. 4,767,833, Japanese Patent Application Laid-Open No. 11-147920, European Patent 703252, Japanese Patent Publication No. 8-199007)

The method for producing transparent ABS includes a method of preparing a transparent ABS resin by grafting a butadiene rubber latex to a monomer mixture having a matching refractive index, for example, a mixture of styrene, acrylonitrile, and (meth) acrylic acid alkyl ester, and butadiene rubber. A one-stage method of grafting a monomer mixture to latex and a styrene, acrylonitrile, and (meth) acrylic acid alkylester mixture were grafted to butadiene rubber latex to prepare an opaque resin having a high rubber content, and a transparent SAN Or it is divided into the two-stage manufacturing method which manufactures transparent ABS by mixing and extruding MS resin.

Korean Unexamined Patent Publication No. 2003-12155 filed by LG Chemical Co., Ltd. adjusts the monomer mixing ratio of methacrylic acid alkyl ester compound or acrylic acid alkyl ester compound, aromatic vinyl compound, and vinyl cyan compound graft copolymerized to conjugated diene rubber latex. By adjusting the refractive index of the monomer mixture similar to the rubber latex refractive index and optimizing the molecular weight to produce a transparent ABS.

Korean Unexamined Patent Publication No. 2003-33236 filed by Cheil Industries Co., Ltd., 20-60 parts by weight of an alkyl methacrylate monomer, and 10-70 parts by weight of a diene-based rubbery polymer having an average particle diameter of 0.05-0.5 µm 25-5 parts by weight of a vinyl monomer and 0-10 parts by weight of an unsaturated nitrile monomer are graft-reacted to prepare a graft polymer latex, and 0.0001-0.05 parts by weight of a silicone oil is added thereto to a SAN resin or MS. Disclosed is a two-stage manufacturing method of mixing a resin to produce a transparent ABS resin having excellent impact resistance and transparency.

In the latter case, there is an advantage in that it is possible to manufacture a variety of rubber content by adjusting the content ratio of the opaque resin and SAN, but the rubber component in increasing the rubber content or increasing the average particle size of the diene rubber component being used The problem is found that the average particle size of is increased and the polymerization stability and storage stability of the latex itself are decreased at high solids content.

Therefore, there is an urgent need for an excellent thermoplastic transparent resin having improved latex stability, impact resistance and colorability.

In addition, there is a continuing need for a method in which a mixture of somewhat incompatible transparent resins such as SAN and PMMA mixtures can be used as a matrix of rubber-reinforced transparent resins.

It is an object of the present invention to provide a graft copolymer for producing a transparent resin having good latex stability.

It is another object of the present invention to provide a novel transparent resin having good impact resistance, gloss, and combustibility.

Another object of the present invention is to provide a rubber-reinforced transparent resin using a mixture of SAN and PMMA as a matrix.

In order to achieve the above object, the present invention is a methacrylic acid alkyl ester in a latex mixture consisting of a small particle diene rubber polymer having an average particle diameter of 700-1500 kPa and a large particle diene rubber polymer having an average particle diameter of 2000-4000 kPa Preparing a graft resin by graft polymerizing a monomer mixture including an aromatic vinyl compound, and a vinyl cyanide compound using an alkylaryl sulfonate salt emulsifier and a dispersant; And mechanically kneading the graft resin and the transparent resin having a refractive index difference within ± 0.005.

In the present invention, it is preferable to use a mixture of a large particle rubber and a small particle rubber so that the graft polymer can increase the transparency of the final product, reduce haze, and improve colorability. When the content of the large-diameter rubber is too small, the impact strength of the final product may be lowered. When the content of the small-diameter rubber is less, the transparency of the final product is lowered and the haze is increased.

In the practice of the present invention, it is preferable that the graft polymer uses an alkylarylsulfonate as an emulsifier to prevent butadiene latex from being unstable due to the alkyl methacrylate compound during the graft polymerization, more preferably. It is recommended to use with dispersants such as KCl, KOH, KHCO ₃ , Na ₂ CO ₃ , NaHSO ₃ , Na ₃ PO ₄ , Na ₄ P ₂ O 7, NaCl. In a preferred embodiment of the present invention, the alkylarylsulfonate and the dispersant are 0.2-0.5 parts by weight and 0.01-0.5 parts by weight, respectively, to 100 parts by weight of the graft resin in order to prevent instability of the latex due to excessive or underuse. It is good to use as a range. Here, it is more preferable that the total amount of alkylarylsulfonate used is divided into before and after graft polymerization.

In the present invention, in order to simplify the process and maintain the stability of the latex, it is preferable to use the small particle rubber by enlarging the particle size rubber polymer.

In the present invention, the rubber content in the graft resin is 30-60% by weight, preferably 40% by weight or more, more preferably 50% by weight or more to facilitate the control of the content and components of the matrix resin It is good to use as a range.

In the present invention, the graft resin is 10-40% by weight, the transparent resin is mixed within the range of 60-90% by weight of the refractive index difference within ± 0.005 is preferably mixed. In a preferred embodiment of the invention, the transparent resin is a mixture of SAN / PMMA.

In an aspect of the present invention, a graft resin prepared by grafting a methacrylic acid alkyl ester, an aromatic vinyl compound, and a vinyl cyanide compound to a diene rubber polymer having two average particle diameters has a refractive index difference of ± It provides a rubber-reinforced transparent thermoplastic resin consisting of 60-90% by weight of PMMA / SAN mixed resin within 0.005.

In the practice of the present invention, the graphene resin is 20 to 40 parts by weight of the alkyl methacrylate compound 30 to 60 parts by weight, preferably 40 to 60 parts by weight, more preferably 49 to 60 parts by weight of the diene rubber It is prepared by graft copolymerization of 10 to 20 parts by weight of aromatic vinyl compound and 1 to 10 parts by weight of unsaturated nitrile compound.

The present invention relates to a mixture of alkyl methacrylate monomers, aromatic vinyl monomers and unsaturated nitrile monomer mixtures by appropriately using emulsifiers and dispersants of alkaryl sulphonate salts in diene rubber latex mixtures having different particle sizes with high rubber content. Graft polymerization has the effect of increasing the polymerization stability of the graft resin and maintaining the impact resistance, which is the final physical properties of the molded article, while providing a thermoplastic resin composition having excellent transparency and colorability and a method of manufacturing the same.

In addition, the high rubber content graft resin is composed of a mixture of large particle size and small particle size, and has good compatibility with transparent resin, impact strength, haze, and the like. Can be used as a matrix.

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

In the present invention, the graft resin includes 5 to 25 parts by weight of a diene rubber polymer (R ₁ ) having an average particle diameter of 700 to 1500 kPa and 25 to 50 parts by weight of a diene rubber polymer (R ₂ ) having an average particle diameter of 2000 to 4000 kPa. It is prepared by graft copolymerization of 20 to 40 parts by weight of an alkyl methacrylate compound, 10 to 20 parts by weight of an aromatic vinyl compound, and 1 to 10 parts by weight of an unsaturated nitrile compound to a rubber latex mixture (R) having a high solid content.

In the present invention, the mixing ratio of the polymers having different particle diameters (R ₁ , R ₂ ) constituting the diene rubber latex mixture used in the manufacture of the graft resin may affect physical properties such as transparency, colorability, and impact resistance of the product. It is an important factor. In rubber polymers with a constant gel content, the mixing resistance (R1 / R2) >> 1 reduces the impact resistance of the g-ABS resin, but the gloss or transparency is improved and the mixing ratio (R1 / R2) << 1 is the gloss of the g-ABS resin. However, transparency decreases but impact strength improves.

In addition, the difference in refractive index of the polymer obtained in each step to prepare the transparent resin should be within ± 0.005. The refractive index of each component used by this invention is about 1.519 polybutadiene, 1.49 methyl methacrylate, 1.59 styrene, and 1.518 acrylonitrile.

Process for producing a thermoplastic transparent resin in the present invention is 1) graft resin manufacturing process; It can be divided into a) polybutadiene rubber latex manufacturing process, b) graft copolymer manufacturing process, and 2) kraft resin and styrene-based transparent resin are kneaded to produce transparent resin having excellent impact resistance, colorability and transparency. .

1) Graft Resin Manufacturing Process

a) Polybutadiene Rubber Latex Manufacturing Process

After the monomer, ion-exchanged water, primary emulsifier, initiator, molecular weight regulator, and crosslinking agent were added, the temperature was raised to an internal temperature of 30 ° C. to 60 ° C. to initiate emulsion polymerization. The secondary emulsifier is added to continue the polymerization. When the polymerization is carried out for 14 hours, the reaction conversion rate is 98% or more, and it is possible to prepare a rubber latex (R ₁ ) having a rubber particle having a size of 700-1500Å with stable latex. The gel content of the rubber latex obtained at this time is to be 80 ~ 90 wt%.

In addition, in order to manufacture a rubber latex (R ₂ ) having an average particle diameter of 2000 to 4000 mm ₃ , a particle copolymer is enlarged by using a polymer copolymer in the rubber latex (R ₁ ). The polymer copolymer may include 1 to 30 parts by weight of one or two or more kinds of a mixture of water-soluble acrylic acid, methacrylic acid, acrylamide, methyl acrylamide and butyl acrylate, ethyl acrylate, 1,3-butadiene, etc. It can be produced in one or two or more mixtures 70 ~ 99 parts by weight, the pH of the latex is characterized in that the viscosity is less than 30cps 2-4.

The particle enlargement method is based on alkylbenzene soda based on 100 parts by weight of rubber latex (R ₁ ) having a rubber particle of 700 to 1500 의 size of one or more mixtures of dodecylbenzenesulfonate, aurylbenzenesulfonate, linear alkylsulfonate and the like. After adding 0.05 ~ 0.5 parts by weight of an emulsion solution prepared by diluting the solid content to 10 ~ 20% in ion-exchanged water, gradually adding 0.8 ~ 2.5 parts by weight of copolymer latex, a particle thickening agent, to increase the size of the rubber with 90% by weight. When the rubbery polymer within the range of 2000 ~ 4000Å is obtained, 0.5 ~ 1.0 parts by weight of alkali such as potassium hydroxide and sodium carbonate are added to the alkaline aqueous solution of 5-20% of the solid content diluted with ion-exchanged water, and then stabilized again. do.

b) graft copolymer manufacturing process

30 to 60 parts by weight of the rubber latex mixture (R ₁ , R ₂ ) prepared by the above method, 20 to 40 parts by weight of an alkyl methacrylate compound, 10 to 20 parts by weight of an aromatic vinyl compound, and 1 to 10 parts by weight of an unsaturated nitrile compound The monomer mixture containing parts is graft copolymerized using a mixture containing an emulsifier, a dispersant, a polymerization initiator and the like.

Emulsifiers commonly used in emulsion polymerization include soaps of fatty acids, alkali salts of rosin acids, sulfonated alkyl esters, and alkylaryl sulfonate salts. In the graft polymerization, 0.2 to 0.5 parts by weight of alkylaryl sulfonate salts are used. use. As a dispersant, 0.01 to 0.5 parts by weight of KCl, KOH, KHCO ₃ , Na ₂ CO ₃ , NaHSO ₃ , Na ₃ PO ₄ , Na ₄ P 2 O 7, NaCl, and the like, alone or in a mixture of two or more thereof, are used. As a polymerization initiator, a hydroperoxide type such as cumene hydroperoxide, dibutyl hydroperoxide, or benzoyl peroxide, which is an oil-soluble initiator, was used, and 0.06 to 0.1 parts by weight is used. The solidified solids (%) of the graft copolymer latex prepared above is measured to check the stability.

In the present invention, it is very important for the transparent resin to have a refractive index of ± 0.005 or less in which the mixture ratio of the polybutadiene rubber latex and each monomer grafted is within ± 0.005.

2) Transparent resin manufacturing process with excellent impact resistance, coloring and transparency

The graft copolymer latex is obtained through the coagulation, dehydration and drying process to obtain a g-ABS resin in powder form and kneading with the transparent resin to prepare a transparent resin having improved impact resistance and transparency. The preferred transparent resin is a compatible SAN / PMMA mixture. At this time, the total refractive index of the kneaded transparent resin is characterized in that within 1.513 ~ 1.519.

Example

Example 1

15 parts by weight of butadiene rubber latex (R ₁ ) with an average particle diameter of 800 A and a gel content of 85%, 35 parts by weight of butadiene rubber latex (R ₂ ) with an average particle diameter of 2500Å and a gel content of 75%, 100 parts by weight of ion-exchanged water 0.12 parts by weight of an oil-soluble initiator cumene hydroperoxide, 0.8 parts by weight of an alkylarylsulfonate salt emulsifier, 0.3 parts by weight of an alkylarylsulfonate salt emulsifier, 0.05 parts by weight of sodium pyrophosphate, 0.03 parts by weight of potassium hydroxide, A mixture of 20 parts by weight of ion-exchanged water, 38 parts by weight of methyl methacrylate, 10 parts by weight of styrene, and 2 parts by weight of acrylonitrile was continuously charged at 75 ° C. for 3 hours, and then aged at the same temperature for 1 hour to complete the reaction. do.

0.2 parts by weight of a phenol-sulfurizing agent and a sulfur-based antioxidant were added to the prepared latex, and the mixture was sufficiently stirred. Then, 100 parts by weight of ion-exchanged water was added, and 0.5 parts by weight of magnesium sulfate was added while the temperature was raised and stirred to 90 ° C. To obtain particles. Subsequently, the resultant was dehydrated, washed, and dried in a centrifuge to obtain a graft resin (g-ABS) in powder form.

In order to evaluate the final physical properties of the prepared g-ABS, 45 parts by weight of PMMA resin, 25 parts by weight of SAN and 0.5 parts by weight of ethylene bis-stearamide, 0.1 parts by weight of antioxidant and 0.2 parts by weight of black dye in graft resin After the addition, after mixing, pressure and injection process to prepare a standard specimen and to measure the final physical properties according to the test method shown in Table 1 below.

Solid Coagulation-1 (%): (Dry Coagulation / Polymer Solid) × 100

Solidified solids-2 (%): Maron Test (8000 rpm, 10 minutes, 30wt%)

(Dryed amount of coagulated after experiment / Latex solid before experiment) × 100

Impact Strength (Kgcm / cm): Use 1/4 inch injection test specimen in accordance with ASTM D256

HAZE (%): ASTM D1003

Blackness (L value): L value is measured using a Color Difference Meter (Nippon Denshoku Kogyo).

Example 2

The rubber latex mixture was 15 parts by weight of butadiene rubber latex (R ₁ ) having an average particle diameter of 800 mm and a gel content of 85%, and 35 parts by weight of butadiene rubber latex (R ₂ ) having an average particle diameter of 2500 mm and a gel content of 75%, ion exchange. A rubber latex mixture containing 100 parts by weight and no alkylarylsulfonate salt was used, and the same procedure as in Example 1 was carried out except that 1.1 parts by weight of the emulsifier alkylaryl sulfonate salt was used in the graft polymerization.

Example 3

Methyl methacrylate using 10 parts by weight of butadiene rubber latex (R ₁ ) with an average particle diameter of 800 mm and a gel content of 85% and 25 parts by weight of butadiene rubber latex (R ₂ ) with an average particle diameter of 2500 mm and a gel content of 75% 49 The same procedure as in Example 1 was carried out except that a mixture of parts by weight, 13 parts by weight of styrene, and 3 parts by weight of acrylonitrile were used.

Comparative Example 1

The rubber latex mixture was 15 parts by weight of butadiene rubber latex (R ₁ ) having an average particle diameter of 800 mm and a gel content of 85%, and 35 parts by weight of butadiene rubber latex (R ₂ ) having an average particle diameter of 2500 mm and a gel content of 75%, ion exchange. It was carried out in the same manner as in Example 1 except that it was used as a rubber latex mixture containing 100 parts by weight and the graft emulsifier was used 0.8 parts by weight of sodium oleate in place of the alkylarylsulfonate salt.

Comparative Example 2

The rubber latex was carried out in the same manner as in Example 1 except that 50 parts by weight of butadiene rubber latex having an average particle diameter of 2500 kPa and a gel content of 75% was used.

Comparative Example 3

The rubber latex was carried out in the same manner as in Example 1 except that 50 parts by weight of styrene-butadiene rubber latex having an average particle diameter of 800 mm 3 and a gel content of 85% was used.

Example Comparative example One 2 3 One 2 3 Solid Coagulum-1 (%) 0.05 0.09 0.06 0.1 0.21 0.05 Solid Coagulum-2 (%) 0.1 0.19 0.11 0.25 0.43 0.09 Impact Strength (Kgcm / cm) 11.2 10.7 6 8.4 16 2 HAZE (%) 3.1 3.3 3.5 4 10.5 2.5 L value 4.2 4.7 3.8 4.3 6.2 3.4

As can be seen in Table 1, the Example has a low coagulation after polymerization and a coagulation after the Maron test, compared to the comparative example is excellent in the polymerization and storage stability of the latex. In the case of Examples 1 and 2, the same amount of emulsifier is included, but it can be seen that the case where the input before and after the graft polymerization is better than the case where the input of the latex is more stable. In the case of Comparative Example 2, the impact value is improved by using a rubber latex consisting of only a large particle size, but it can be seen that transparency is very low. In the case of Comparative Example 3, the transparency was improved by using a rubber latex consisting of only small particle size, but it can be seen that the impact value is very low. When rubber latexes having different particle diameters are used in the equivalent rubber latex content, the impact value is maintained, and the transparency and colorability are also excellent due to the relatively low HAZE value and L value.

Claims (9)

Methacrylic acid alkyl ester, aromatic vinyl compound, and vinyl cyanide compound are included in a latex mixture composed of a small particle diene rubber polymer having an average particle diameter of 700-1500 mm 3 and a large particle diene rubber polymer having an average particle diameter of 2000-4000 mm Graft polymerizing a monomer mixture using an alkylaryl sulfonate salt emulsifier and a dispersant to prepare a graft resin; And Mechanically kneading the graft resin and the transparent resin having a refractive index difference within ± 0.005; Thermoplastic transparent resin manufacturing method comprising a. The method of claim 1 wherein the graft is a polymer having an average particle diameter of 700 ~ 1500Å a diene rubber polymer (R ₁₎ 5 ~ a diene rubber polymer 25 parts by weight and a mean particle size of _{2000 ~ 4000Å (R 2) 25} ~ 50 20 to 40 parts by weight of the methacrylic acid alkyl ester compound, 10 to 20 parts by weight of the aromatic vinyl compound, and 1 to 10 parts by weight of the unsaturated nitrile compound are manufactured by graft copolymerization. The method of claim 1 or 2, wherein the dispersant is selected from the group consisting of KCl, KOH, KHCO ₃ , Na ₂ CO ₃ , NaHSO ₃ , Na ₃ PO ₄ , Na4P2O7, NaCl, or a mixture of two or more thereof. Thermoplastic transparent resin manufacturing method characterized in that. The method of claim 1, wherein the alkylarylsulfonate salt emulsifier is used in an amount of 0.2-0.5 parts by weight, and a dispersant is used in an amount of 0.01-0.5 parts by weight based on 100 parts by weight of the graft resin. 5. The method of claim 4, wherein the alkylarylsulfonate is added separately before and after graft polymerization. The method of claim 1 or 2, wherein the large-diameter rubbery polymer is produced by enlarging a small-diameter rubbery polymer in a particle size. 10-40% by weight of a graft resin prepared by grafting an alkyl methacrylate, an aromatic vinyl compound, and a vinyl cyanide compound on a diene rubber polymer having two average particle diameters, and a PMMA / SAN mixture having a refractive index difference of within ± 0.005. Rubber-reinforced transparent thermoplastic resin composition consisting of 60-90% by weight resin. According to claim 7, wherein the graft resin is 30-60 parts by weight of the diene rubber, 20-40 parts by weight of the alkyl methacrylate compound, 10-20 parts by weight of the aromatic vinyl compound, 1-10 parts by weight of a saturated nitrile compound A rubber-reinforced transparent thermoplastic resin composition, comprising a portion. The rubber-reinforced thermoplastic resin composition according to claim 7 or 8, wherein the average particle diameter of the diene rubber polymer is 700-1500 mm and 2000-4000 mm.