KR20050033944A - Method for preparing acrylonitrile-butadiene-styrene resin having high strength and gloss - Google Patents

Abstract

Provided is a preparation method for acrylonitrile-butadiene-styrene resin showing high strength and gloss which adds ethylenes rubber to butadiene rubber to improve impact intensity and gloss and raise heat deflection temperature. The preparation method for acrylonitrile-butadiene-styrene resin showing high strength and gloss comprises the steps of: (i) melting 40-65wt% of styrenes monomers and 10-25wt% of acrylonitriles monomers in 10-45wt% of a reactive solvent to prepare a mixing solution; (ii) melting 5-12wt% of butadienes rubber and 1-5wt% of ethylenes rubber in the mixing solution to prepare a polymerization solution; (iii) adding 0.01-0.1wt% of an initiator and 0.01-1wt% of a weight adjuster to the polymerization solution; and (iv) firstly polymerizing at 90-130deg.C and then secondly polymerizing at 130-160deg.C.

Description

Method for preparing acrylonitrile-butadiene-styrene resin having high impact and high gloss {Method for Preparing Acrylonitrile-Butadiene-Styrene Resin Having High Strength and Gloss}

The present invention relates to a method for producing acrylonitrile-butadiene-styrene resin having high impact and high gloss. More specifically, in the present invention, the particles of the rubber in the resin prepared by graft copolymerization of styrene monomer and acrylonitrile monomer to ethylene rubber and butadiene rubber by continuous bulk polymerization method have impact resistance and gloss in a bimodal form. The present invention relates to a method for producing acrylonitrile-butadiene-styrene resin having excellent high impact and high gloss.

A method of preparing an acrylonitrile-butadiene-styrene (hereinafter referred to as 'ABS') resin, which is a rubber modified styrene copolymer resin, is an emulsion polymerization method, a suspension polymerization method, a solution polymerization method, and a bulk polymerization method. And suspension polymerization and bulk polymerization, and emulsion polymerization and block polymerization together. Among these methods, the emulsion polymerization method and the bulk polymerization method are mainly used in the production site, and the emulsion polymerization method is most preferred. The ABS resin produced by the emulsion polymerization method has a mechanical property and glossiness of 0.2 to 1.5 µm in average, with the rubber particles present in the dispersed phase in a continuous styrene-acrylonitrile copolymer (SAN copolymer). However, due to the nature of the emulsion polymerization process, emulsifiers and flocculants, which must be used, are not completely removed in the flocculation and dehydration process, but remain in the final product to cause deterioration of physical properties, and it is difficult to treat contaminated water used as a polymerization medium. In addition, since the process of flocculation and dehydration after polymerization is required separately, it is less economical than the bulk polymerization which is a continuous process.

In the bulk polymerization, a certain amount of butadiene rubber or styrene-butadiene rubber is dissolved in a solution in which a fixed proportion of styrene monomer and acrylonitrile monomer are dissolved in a reaction medium, and then an appropriate amount of a reaction initiator, a molecular weight regulator and other additives are mixed. And then heating to polymerize. As the polymerization proceeds, SAN is formed as a copolymer of styrene monomer and acrylonitrile monomer as the polymerization proceeds. At this time, the styrene monomer and acrylonitrile monomer are dissolved in butadiene rubber or styrene-butadiene rubber. To produce graft SAN copolymers. The resulting SAN copolymer forms two phases without mixing with the rubber dissolved in the reaction medium from the beginning of the reaction to make the entire polymerization solution non-uniform. In the heterogeneous phase, the rubber phase dissolved in the polymerization solution forms a continuous phase at the beginning of the polymerization reaction with low conversion rate, but the upper blood of the copolymer of styrene or styrene derivatives and acrylonitrile or acrylonitrile derivatives increased as the reaction proceeds. If is greater than the upper blood of the rubber in the polymerization solution, the former copolymer forms a continuous phase. This phenomenon is called 'phase inversion' and the point where the volume of the copolymer phase and the rubber phase become equal is called the phase inversion point. After the phase inversion occurs, the rubber phase becomes a dispersed phase to form rubber particles in the finally prepared resin.

The ABS resin thus manufactured is applied to various fields such as home appliances, office equipment parts, automobile parts, etc., because of excellent moldability, dimensional stability of molded products, and impact resistance. The mechanical properties and gloss of ABS resins are affected by the size, composition and content of rubber particles in the resin.For example, low rubber content or small rubber particles in the resin improve tensile strength and gloss but decrease elongation and impact strength. There is a disadvantage, the increase in the rubber content in the resin can improve the impact strength, but on the contrary, there is a problem that the gloss is lowered. Therefore, in order to solve this problem, the rubber particles dispersed in the resin are bimodal, so that the large rubber particles are advantageous for the impact strength and the small rubber particles are favorable for the gloss. Is manufactured, and the result is not generally satisfactory.

U.S. Patent Nos. 2694692, 3243481, 3658946 and EP 400479 disclose methods for dissolving rubber in aromatic vinyl compounds and unsaturated nitrile compounds and polymerizing them using radical initiators in the rubber solution. The composition prepared as described above has a disadvantage in that mechanical properties are excellent but gloss is reduced.

U.S. Patent No. 4,640,959 and European Patent No. 103657 use high viscosity butadiene rubber having a solution viscosity of 120 cps in a 5% by weight styrene solution to control the composition of the monomer, the reaction initiator and the molecular weight regulator, This article describes a method for producing relatively large particles of ABS resin with an average particle diameter of 1.5 um by the bulk polymerization method. The composition thus prepared has a disadvantage that the particles are large and the impact strength is excellent but the gloss is lowered.

U.S. Patent No. 4,146,589 discloses a method of preparing a resin by polymerizing a rubber solution having a large particle and a rubber solution having a small particle in each reactor and then mixing the same. In US Patent 4,254,236, a rubber solution is first described. It discloses a method for producing a resin having a bimodal rubber particles by polymerization in a second reactor and a rubber solution having the same composition in a second reactor.

In US Patent Nos. 511023, 4587294, 4639494, European Patent No. 277687 and Japanese Patent Nos. 59-232140, 59-179611, resins were prepared using star-branched rubber, and Japanese Patent No. 5- 194676, 5-247149, 6-166729, 6-65330 and European Patent No. 160974 used bimodal resins in which small rubber particles and large rubber particles were mixed using star-shaped rubber and linear rubber. All were not satisfactory in balancing gloss with mechanical properties.

In order to solve the above problems, an object of the present invention is to provide an ABS resin manufacturing method having an excellent impact strength and gloss and high heat deformation temperature by adding ethylene rubber to butadiene rubber.

In addition, an object of the present invention is to add an ethylene-based rubber to butadiene rubber to provide an ABS resin excellent in impact strength and gloss, and high heat deformation temperature.

The above and other objects of the present invention can be achieved by the present invention described below.

In order to achieve the above object and object, the present invention provides a method for producing acrylonitrile-butadiene-styrene resin by a continuous bulk polymerization method,

5 to 12% by weight of butadiene rubber and 1 to 5% by weight of ethylene rubber were added to a mixed solution of 40 to 60% by weight of styrene monomer and 10 to 25% by weight of acrylonitrile monomer in 10 to 45% by weight of reaction solvent. 0.01 to 0.1% by weight of the initiator and 0.01 to 1% by weight of the molecular weight regulator were added to the polymerization solution prepared by dissolving and polymerization was carried out at a temperature of 90 to 130 ° C. in one step, and 130 to 160 ° C. in two steps. It provides a method for producing acrylonitrile-butadiene-styrene resin comprising the step of polymerization at a temperature.

The reaction solvent may be at least one selected from the group consisting of toluene, ethylbenzene, and xylene, and 10 parts by weight of the raw material monomer (styrene monomer + acrylonitrile monomer) in order to lower the viscosity of the polymerization solution. To 45 parts by weight.

The butadiene-based rubber may be butadiene or styrene-butadiene-based rubber.

The styrene monomers are styrene, α-methylstryene, p-bromostryene, p-methylstryene, p-chlorostryene , o-bromostryene and mixtures thereof.

The acrylonitrile-based monomer may be selected from the group consisting of acrylonitrile, methacrylonitrile, and ethacrylonitrile.

The ethylene rubber is selected from the group consisting of chlorinated polyethylene rubber (CPE), ethylene-propylene rubber (EP), and ethylene-propylene-diene rubber (EPDM) Can be.

The weight average molecular weight of the ethylene-based rubber may be 150,000 to 400,000.

The initiator is 1,1-bis (t-butylperoxy) -3,3,5-trimethyl cyclohexane {1,1-bis (t-butylperoxy) -3,3,5-trimethyl cyclohexane}, 1,1 -Bis (t-butylperoxy) cyclohexane {1,1-bis (t-butylperoxy) cyclohexane}, 1,1-bis (t-butylperoxy) -2-methyl cyclohexane {1,1-bis ( t-butylperoxy) -2-methyl cyclohexane}, and 2,2-bis (4,4-di-t-butylperoxy cyclohexyl) propane {2,2-bis (4,4-di-t-butylperoxy cyclohexyl It may be an organic peroxide selected from the group consisting of propane}.

The molecular weight modifier may be a thiol-based compound selected from the group consisting of t-dodecyl mercaptan and n-octyl mercaptan.

In addition, the present invention provides an acrylonitrile-butadiene-styrene resin prepared by the above production method.

Hereinafter, the present invention will be described in detail.

Acrylonitrile-butadiene-styrene resin manufacturing method according to the present invention is made of a two-step polymerization process by adding ethylene-based rubber to butadiene rubber in order to provide an ABS resin with excellent impact strength and gloss and high heat deformation temperature. It is characterized by.

That is, 5 to 12 butadiene or styrene-butadiene rubber in a mixed solution of 10 to 45 wt% of styrene monomer and 10 to 25 wt% of acrylonitrile monomer in 10 to 45 wt% of ethyl benzene as a reaction solvent To the polymerization solution prepared by dissolving the weight% and 1 to 5% by weight of the ethylene rubber, 0.01 to 0.1% by weight of the initiator and 0.01 to 1% by weight of the molecular weight regulator are added to the reactor continuously, the temperature of 90 to 130 ℃ in one step In the second step, at a temperature of 130 to 160 ° C., to remove the unreacted monomer and the reaction medium at a temperature of 200 to 260 ° C. in a volatilizer when the polymerization conversion rate was 65 to 95%, and the pelletized ABS resin To prepare.

In the present invention, the polymerization process is preferably by bulk polymerization, and ethyl benzene is preferably used as the reaction solvent. In addition, the content of the reaction solvent is preferably 10 to 45% by weight, it is difficult to control the high viscosity at less than 10% by weight, when the content exceeds 45% by weight of the rubber particles produced during the polymerization process effectively I can't control it.

The styrene-based monomers used as the raw material of the ABS resin of the present invention are styrene, α-methyl styrene (α-methylstryene), p-bromostryene, p-methyl styrene (p-methylstryene), p -Chlorostyrene (p-chlorostryene), o-bromostryene (o-bromostryene), may be used to select the analogs thereof, the content of the styrene monomer is preferably 40 to 60% by weight.

In addition, acrylonitrile-based monomers may be used acrylonitrile, methacrylonitrile, ethacrylonitrile, and the like, and the content of acrylonitrile-based monomers is 10 to 25% by weight. It is preferable.

In the present invention, in order to improve impact strength and gloss, ethylene-based rubber is added together with butadiene rubber during polymerization, and the ethylene-based rubber is chlorinated polyethylene rubber (CPE), ethylene-propylene rubber, EP), ethylene-propylene-diene rubber (EPDM), and the like, and the weight average molecular weight is preferably 150,000 to 400,000, and more preferably 200,000 to 350,000. In addition, the content of the ethylene rubber is preferably 1 to 5% by weight.

In the present invention, the polymerization reaction is initiated, and an organic peroxide initiator is used to control the graft reaction and the conversion rate. The organic peroxide initiator is 1,1-bis (t-butylperoxy) -3,3,5-. Trimethyl cyclohexane {1,1-bis (t-butylperoxy) -3,3,5-trimethyl cyclohexane}, 1,1-bis (t-butylperoxy) cyclohexane {1,1-bis (t-butylperoxy) cyclohexane}, 1,1-bis (t-butylperoxy) -2-methyl cyclohexane {1,1-bis (t-butylperoxy) -2-methyl cyclohexane}, 2,2-bis (4,4-di and -t-butylperoxy cyclohexyl) propane {2,2-bis (4,4-di-t-butylperoxy cyclohexyl) propane}. The content of the initiator is preferably 0.01 to 0.1% by weight.

In the present invention, it is preferable to use a thiol-based compound such as t-dodecyl mercaptan and n-octyl mercaptan at 0.01 to 1% by weight as a molecular weight regulator for controlling the viscosity of the resin, the size of the particles, and the particle distribution. .

In addition, the present invention provides an acrylonitrile-butadiene-styrene resin prepared by the above production method.

Hereinafter, the present invention will be described in more detail with reference to the following examples, but the scope of the present invention is not limited to the examples.

Example 1

7.6% by weight of butadiene rubber was dissolved in a mixed solution of 45.88% by weight of styrene and 11.5% by weight of acrylonitrile in 34% by weight of ethyl benzene as a reaction solvent, followed by 1% of chlorinated rubber and 1,1-bis (t) as an initiator. Butyl peroxy) -3,3,5-trimethyl cyclohexane (1,1-Bis (t-butylperoxy) -3,3,5-trimethyl cyclo hexane) 0.02% by weight was added to prepare a polymerization solution. The prepared polymerization solution was introduced into a 26L reactor at a rate of 12 L / hr, polymerized at a temperature of 125 ° C. in the first reactor, polymerized at a temperature of 135 ° C. in the second reactor, and 140, respectively in the third reactor and the fourth reactor. When the polymerization was carried out at a temperature of 145 ° C. to reach a polymerization conversion of 90%, the unreacted monomer and the reaction medium were removed at a temperature of 240 ° C. in a volatilization tank to prepare an ABS resin in pellet form.

The physical properties of the ABS resin thus prepared were measured, and the results are shown in Table 1.

Example 2

ABS resin was prepared in the same manner as in Example 1 except for adding 6.6% butadiene rubber and 2% chlorinated rubber when preparing the polymerization solution, and measured physical properties of the ABS resin thus prepared. Is shown in Table 1.

Example 3

ABS resin was prepared in the same manner as in Example 1 except for adding 5.6% butadiene rubber and 3% chlorinated rubber when preparing the polymerization solution, and measured physical properties of the ABS resin thus prepared. Is shown in Table 1.

Example 4

ABS resin was prepared in the same manner as in Example 1, except that 3.6% butadiene rubber and 5% chlorinated rubber were prepared when preparing the polymerization solution, and the physical properties of the ABS resin thus prepared were measured. Is shown in Table 1.

Comparative Example 1

The ABS resin was manufactured in the same manner as in Example 1, except that 8.6% of butanediene rubber was added without adding chlorinated rubber when preparing the polymerization solution, and the physical properties of the ABS resin thus prepared were measured. Is shown in Table 1.

Physical properties of the ABS resins prepared in Examples and Comparative Examples were measured by the following method.

◎ Particle shape: Observation was performed using a transmission electron microscope (TEM, Jeol JEM-1010). The samples were treated with osmium tetroxide and then made into ultra-tear cut specimens using a microtome.

? Average particle size of rubber particles: 0.5 g of styrene-based rubber modified resin was dissolved in 100 mL of methylethylkenone, and the average particle diameter of the rubber particles was measured using a Coulter counter (Beckman Coulter LS230).

Izod Impact: Measured by ASTM D256 method.

◎ Tensile strength and elongation: It was measured by ASTM D638 method.

◎ Gloss: An injection test piece having a thickness of 3 mm was prepared and measured according to ASTM 1003.

◎ Heat Deflection Temperature (HDT): Measured by ASTM D648 method.

division Example Comparative example One 2 3 4 One Butadiene rubber content in the polymerization solution (wt%) 7.6 6.6 5.6 3.6 8.6 Chlorinated rubber content in the polymerization solution (wt%) One 2 3 5 0 Rubber Particle Distribution Form * 0 0 0 0 X Average rubber particle size (㎛) 2.74 1.88 1.56 1.07 3.80 Impact strength (㎏㎝ / ㎝) (1/4 ") 16.2 19.3 24.7 20.5 14.7 (1/8 ") 19.4 21.3 27.1 24.0 16.9 Tensile Strength (㎏㎠) 324 331 357 370 304 % Elongation 41.7 38.7 23.5 19.4 49.7 Polish(%) 50.5 67.1 88.4 87.3 25.7 Heat Deflection Temperature (℃) 76.1 76.8 76.9 77.4 75.1

*) 0: Bimodal, X: Unimodal

As shown in Table 1, it can be seen that the ABS resins of Examples 1 to 4 prepared using chlorinated rubber have higher impact strength, tensile strength, elongation, gloss, and heat deformation temperature than Comparative Example 1.

As described above, the ABS resin production method according to the present invention is a useful invention having the effect of producing a high impact strength, gloss, heat deformation temperature ABS resin because the rubber particles in the ABS resin has a bimodal form.

While the invention has been described in detail above with reference to the described embodiments, it will be apparent to those skilled in the art that various modifications and variations are possible within the scope and spirit of the invention, and such modifications and variations fall within the scope of the appended claims. It is also natural.

Claims (10)

In the method for producing acrylonitrile-butadiene-styrene resin by a continuous bulk polymerization method, 5 to 12% by weight of butadiene rubber and 1 to 5% by weight of ethylene rubber were added to a mixed solution of 40 to 60% by weight of styrene monomer and 10 to 25% by weight of acrylonitrile monomer in 10 to 45% by weight of reaction solvent. 0.01 to 0.1% by weight of the initiator and 0.01 to 1% by weight of the molecular weight regulator were added to the polymerization solution prepared by dissolving and polymerization was carried out at a temperature of 90 to 130 ° C. in one step, and 130 to 160 ° C. in two steps. Acrylonitrile-butadiene-styrene resin production method comprising the step of polymerization at a temperature. The method of claim 1, The reaction solvent is at least one selected from the group consisting of toluene, ethylbenzene, and xylene, and is used in an amount of 10 to 45 parts by weight based on 100 parts by weight of the raw material monomer (styrene monomer + acrylonitrile monomer). Acrylonitrile-butadiene-styrene resin manufacturing method. The method of claim 1, The butadiene-based rubber is an acrylonitrile-butadiene-styrene resin manufacturing method, characterized in that butadiene or styrene-butadiene rubber. The method of claim 1, The styrene-based monomers are styrene, α-methylstyrene, α-methylstryene, p-bromostryene, p-methylstryene, p-chlorostryene A method for producing acrylonitrile-butadiene-styrene resin, which is selected from the group consisting of o-bromostryene and mixtures thereof. The method of claim 1, The acrylonitrile-based monomer is acrylonitrile (acrylonitrile), methacrylonitrile (methacrylonitrile), ethacrylonitrile (ethacrylonitrile) characterized in that selected from the group consisting of acrylonitrile-butadiene-styrene resin. The method of claim 1, The ethylene rubber is selected from the group consisting of chlorinated polyethylene rubber (CPE), ethylene-propylene rubber (EP), and ethylene-propylene-diene rubber (EPDM) Acrylonitrile-butadiene-styrene resin production method characterized in that the. The method of claim 1, Acrylonitrile-butadiene-styrene resin production method characterized in that the weight average molecular weight of the ethylene-based rubber is 150,000 to 400,000. The method of claim 1, The initiator is 1,1-bis (t-butylperoxy) -3,3,5-trimethyl cyclohexane {1,1-bis (t-butylperoxy) -3,3,5-trimethyl cyclohexane}, 1,1 -Bis (t-butylperoxy) cyclohexane {1,1-bis (t-butylperoxy) cyclohexane}, 1,1-bis (t-butylperoxy) -2-methyl cyclohexane {1,1-bis ( t-butylperoxy) -2-methyl cyclohexane}, and 2,2-bis (4,4-di-t-butylperoxy cyclohexyl) propane {2,2-bis (4,4-di-t-butylperoxy cyclohexyl ) propane} organic peroxide selected from the group consisting of acrylonitrile-butadiene-styrene resin production method. The method of claim 1, Preparation of acrylonitrile-butadiene-styrene resin, characterized in that the molecular weight regulator is a thiol-based compound selected from the group consisting of t-dodecyl mercaptan and n-octyl mercaptan Way. Acrylonitrile-butadiene-styrene resin manufactured by the manufacturing method of any one of Claims 1-9.