KR100665804B1 - High Heat ABS Resin Composition Having Improved Crack and Chemical Resistance - Google Patents

Abstract

The heat resistant ABS resin composition according to the present invention comprises (A) 30 to 70% by weight of diene-based synthetic rubber; And 20 to 35 parts by weight of a diene graft polymer prepared by polymerizing 70 to 30% by weight of a monomer mixture comprising 20 to 30% by weight of a vinyl cyanide compound and 80 to 70% by weight of an aromatic vinyl compound. (B) 1 to 10 parts by weight of the ethylene-alkyl (meth) acrylate copolymer; And (C) (c ₁ ) long chain vinyl cyanide compound-aromatic vinyl compound copolymer; And (c ₂ ) a branched vinyl cyanide compound-aromatic vinyl compound copolymer, wherein the amount of (c ₂ ) is 84.9 to 55 parts by weight of the vinyl cyanide-aromatic vinyl compound copolymer having a content of 20% by weight or more of the total (C). It characterized by consisting of.

Heat resistant ABS resin, impact resistance, chemical resistance, crack resistance

Description

High heat ABS resin composition having improved crack and chemical resistance

Field of invention

The present invention relates to a heat resistant ABS resin composition. More specifically, the present invention has high impact resistance by using ethylene-alkyl (meth) acrylate copolymer and vinyl cyanide compound-aromatic vinyl compound copolymer in diene rubber-modified styrene graft copolymer, and has high chemical resistance and crack resistance. The present invention relates to a heat resistant ABS resin composition having improved properties.

Background of the Invention

Recently, thermoplastic ABS resins having mechanical strength such as high impact resistance and high chemical resistance and crack resistance have been demanded as materials for electric and electronic device parts, automobile parts, and building materials.

Conventionally, the method of increasing the content of the diene-based synthetic rubber in order to increase the crack resistance and impact resistance of ABS, but has a disadvantage in that the heat resistance is greatly reduced as well as the size of the improvement. For example, in the case of a material applied to a part that is applied to a part where a lot of stress is applied, safety problems are often caused by cracking during use, and this tendency is greatly increased in winter when the temperature is lowered. In addition, cracks caused by accumulated stress when exposed to chemicals such as insecticides and cleaning agents during use are greatly promoted, and many cracks are often generated in a short time. Increasing the rubber content greatly improves this problem, but the mechanical strength and heat resistance of the material are greatly reduced, resulting in a problem that falls short of the mechanical properties required for the component.

Accordingly, the present inventors have studied diligently to solve the problems of the conventional ABS resin described above. As a result, the present inventors have simultaneously applied ethylene-alkyl (meth) acrylate copolymer and branched vinyl cyanide compound-aromatic vinyl compound copolymer to provide high impact strength. And ABS chemical composition suitable for molding such as extrusion while having chemical resistance and crack resistance, and have completed the present invention.

An object of the present invention is to provide a heat resistant ABS resin composition excellent in crack resistance.

Another object of the present invention is to provide a heat resistant ABS resin composition excellent in chemical resistance.

Another object of the present invention is to provide a heat resistant ABS resin composition having excellent crack resistance and chemical resistance and excellent mechanical strength.

Another object of the present invention is to provide a heat resistant ABS resin composition having good extrusion moldability.

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

Summary of the Invention

The heat resistant ABS resin composition according to the present invention

(A) 30 to 70% by weight of diene synthetic rubber; And 20 to 35 parts by weight of a diene graft polymer prepared by polymerizing 70 to 30% by weight of a monomer mixture comprising 20 to 30% by weight of a vinyl cyanide compound and 80 to 70% by weight of an aromatic vinyl compound.

(B) 1 to 10 parts by weight of an ethylene-alkyl (meth) acrylate copolymer having the structure of formula (1):

[Formula 1]

R ₁ is a hydrogen atom or a methyl group; R ₂ is a hydrogen atom or a C ₁ -C ₁₂ alkyl group which is an alkyl group of methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, t-butyl, isobutyl, isoamyl and t-amyl; m and n are degrees of polymerization, and the ratio of m and n is 300: 1 to 10:90; And

(C) (c ₁ ) long-chain vinyl cyanide compound-aromatic vinyl compound copolymer, and (c ₂ ) branched vinyl cyanide compound-aromatic vinyl compound copolymer, wherein the content of (c ₂ ) 84.9 to 55 parts by weight of vinyl cyanide-aromatic vinyl compound copolymer, which is at least 20% by weight of C);

Characterized in that consists of.

Hereinafter, the content of the present invention will be described in detail.

Detailed Description of the Invention

(A) diene graft copolymer

The diene graft polymer (A) of the present invention is usually prepared by mixing 30 to 70 wt% of a diene synthetic rubber (based on solids) and 100 wt% of a mixture consisting of 70 to 30 wt% of a monomer of a vinyl cyanide compound and an aromatic vinyl compound. By emulsion polymerization, suspension polymerization, solution polymerization or bulk polymerization.

The monomer mixture of the vinyl cyanide compound and the aromatic vinyl compound is composed of 20 to 30% by weight of vinyl cyanide compound and 80 to 70% by weight of aromatic vinyl compound, and vinyl cyanide compound-aromatic vinyl grafted on diene-based synthetic rubber. The compound copolymer is preferably 40 to 70% by weight based on the total diene graft polymer (A).

The diene synthetic rubbers for preparing the diene graft polymer (A) include polybutadiene, polyisoprene, polychloroprene, butadiene-styrene copolymer, butadiene-acrylonitrile copolymer, and the like. -Styrene copolymer and butadiene-acrylonitrile copolymer are preferred. The average particle diameter of the diene synthetic rubber particles is preferably in the range of 0.1 to 1.0 mu m, more preferably in the range of 0.2 to 0.8 mu m. If the average particle diameter of the rubber particles is less than 0.1 ㎛ it is difficult to show the impact resistance peculiar to rubber, a large particle size of more than 1.0 ㎛ average particle diameter is inefficient because there is no advantage to increase compared to the production efficiency is lowered.

Vinyl cyanide compounds for preparing the diene graft polymer (A) of the present invention include acrylonitrile, methacrylonitrile, and the like, and these may be used alone or in combination.

Aromatic vinyl compounds for preparing the diene graft polymer (A) include styrene, alpha-methylstyrene, pt-butylstyrene, 2,4-dimethylstyrene, vinyltoluene, and the like, which may be used alone or in combination. .

The content of the diene graft copolymer (A) of the present invention is in the range of 20 to 35 parts by weight.

(B) Ethylene-alkyl (meth) acrylate copolymer

The ethylene-alkyl (meth) acrylate copolymer (B) used in the present invention has a structure represented by the following formula (1).

[Formula 1]

Wherein R ₁ is a hydrogen atom or a methyl group; R ₂ is a hydrogen atom or a C _{1 to} C ₁₂ alkyl group which is an alkyl group of methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, t-butyl, isobutyl, isoamyl, t-amyl; m and n are polymerization degrees, and the ratio of m and n is 300: 1-10: 90.

The ethylene-alkyl (meth) acrylate copolymers (B) of the present invention are random, block, multi block or mixtures thereof. In addition, the content of the ethylene / alkyl (meth) acrylate copolymer (B) according to the present invention is preferably in the range of 0.1 to 10 parts by weight, more preferably in the range of 0.5 to 9 parts by weight.

The ethylene-alkyl (meth) acrylate copolymer (B) used in the preparation of the resin composition of the present invention preferably has a melt index of 0.01 to 40 g / 10 min at 190 ° C and 2.16 kgf, preferably 0.1 to 10 g. More preferably, it is / 10 minutes.

(C) Vinyl Cyanide Compound-Aromatic Vinyl Compound Copolymer

(c ₁ ) Long-chain vinyl cyanide compound-aromatic vinyl compound copolymer

The long-chain vinyl cyanide compound-aromatic vinyl compound copolymer (c ₁ ) of the present invention is prepared by a conventional polymerization method using 15 to 50% by weight of a vinyl cyanide compound and 85 to 50% by weight of an aromatic vinyl compound.

As the vinyl cyanide compound for producing the vinyl cyanide compound-aromatic vinyl compound copolymer (c ₁ ), an acrylonitrile, methacrylonitrile, or the like may be used. As the aromatic vinyl compound, styrene, divinylbenzene, alpha-methylstyrene, pt-butylstyrene, 2,4-dimethylstyrene, vinyltoluene, or the like may be used alone or as a mixture. The law, solution polymerization, bulk polymerization and the like are applicable. The weight average molecular weight of the long chain vinyl cyanide compound-aromatic vinyl compound copolymer produced by such a method is in the range of 100,000-400,000.

(c ₂ ) Branched vinyl cyanide compound-aromatic vinyl compound copolymer

Description of the side-branched vinyl cyanide compound-aromatic vinyl compound copolymer (c ₂ ) used in the production of the vinyl cyanide compound-aromatic vinyl compound copolymer (C) of the present invention is described above. Basically the same as the description of the aromatic vinyl compound copolymer (c ₁ ), in addition to using a multifunctional compound in order to give a molecular structure having a number of long side branches.

The side chain-type cyanide vinyl compound-aromatic vinyl compound copolymer in the presence of a polyfunctional compound of 0.001 to 0.05% by weight relative to 15 to 50% by weight of a vinyl cyanide compound and 85-50% by weight of an aromatic vinyl compound in the total (c ₂₎ It is prepared by the conventional polymerization method.

As the polyfunctional compound, divinylbenzene and the like may be used. In addition, a compound having a plurality of reactors (polyfunctional) may be used to replace part or all of the divinylbenzene, and the compound having a plurality of reactors may be a polyfunctional aromatic vinyl. Compound, triaryl isocyanurate, polyfunctional mercaptan, polyfunctional peroxide, or a compound that can play a similar role. The weight average molecular weight of the produced branched copolymer (c ₂ ) is in the range of 200,000 to 2,000,000.

In the thermoplastic ABS resin composition according to the present invention, (A) is 20 to 35 parts by weight, (B) is 0.1 to 10 parts by weight, (C) is 84.9 to 55 parts by weight based on 100 parts by weight of the total resin composition. ) Is composed of (c ₁ ) and (c ₂ ), characterized in that (c ₂ ) is at least 20% by weight of the total (C). When the content of (A) or (B) exceeds the above range, mechanical properties such as bending characteristics and heat resistance are low, which is not practical. If the content of (A) or (B) is smaller than the above range, crack resistance and impact resistance are lowered, which is not practical. In addition, when the content of (c ₂ ) is less than the above range, not only the chemical resistance is lowered but also the fluidity is greatly increased, so that moldability such as extrusion is not practical, and the content of (c ₂ ) is larger than the above range, It is not practical because the fluidity is greatly lowered, which causes difficulty in molding due to a decrease in fluidity. The content of (c ₁₎ are associated to the content of (c _2), when the content of (C) exceeds the above range mothamyeo not practical to lower the impact resistance, mothada not lower the heat resistance viable if less than the above range, .

The thermoplastic ABS resin composition of the present invention may be prepared by optionally further adding specific impact modifiers, antioxidants, lubricants, light stabilizers, fillers, inorganic additives, pigments and / or dyes, and the like.

The present invention will be further illustrated by the following examples, which are merely illustrative of the present invention and are not intended to limit or limit the scope of the present invention.

Example

(A) diene graft polymer, (B) ethylene-alkyl (meth) acrylate copolymer, (C) (c ₁ ) vinyl cyanide compound-aromatic vinyl compound air used in Examples and Comparative Examples of the present invention The specifications of the copolymer, (c ₂ ) branched vinyl cyanide compound-aromatic vinyl compound copolymer are as follows.

(A) diene graft polymer

A core-shell graft ABS resin having a rubber particle diameter of about 0.3 μm was prepared using 42 parts by weight of a monomer mixture composed of 25% by weight of acrylonitrile and 75% by weight of styrene with 58 parts by weight of butadiene rubber. It was used after.

(B) Ethylene-alkyl (meth) acrylate copolymer

(b ₁ ) An ethylene-alkyl (meth) acrylate copolymer having a melt index of 5.0 g / 10 min at 190 ° C. and 2.16 kgf conditions was used.

(b ₂ ) An Elvaloy AC (trade name) EMA-1330 manufactured by Dupont with a melt index of 5.0 g / 10 min at 190 ° C. and 2.16 kgf was used.

(C) Vinyl Cyanide Compound-Aromatic Vinyl Compound Copolymer

(c ₁ ) Long-chain vinyl cyanide compound-aromatic vinyl compound copolymer

A styrene-acrylonitrile copolymer resin having an acrylonitrile content of 20% by weight, a styrene content of 80% by weight, and a weight average molecular weight of 150,000 was used.

(c ₂ ) Branched vinyl cyanide compound-aromatic vinyl compound copolymer

A styrene-acrylonitrile copolymer resin having a weight average molecular weight of about 650,000 in which divinylbenzene was added 0.02% by weight based on 100% by weight of 20% by weight acrylonitrile content and 80% by weight styrene content was used.

Examples 1-4

Each of the above components was added in an amount as described in Table 1, followed by melting and kneading extrusion to prepare pellets. The ethylene-alkyl (meth) acrylate copolymer (B) was evaluated separately according to the examples by marking products directly polymerized and commercially available products (b ₁ ) and (b ₂ ), respectively. The extrusion was performed using a twin screw extruder L / D = 29, 45 mm in diameter and the cylinder temperature was set to 250 ℃. The fluidity was measured by the prepared pellets, and the physical properties of the specimens were injection molded to evaluate the physical properties. After making a 3 mm hole in the specimen, create a stress by forcing a 4 mm diameter nail, immersing it in various organic solvent mixtures, and measuring the time and number of cracks. The results are shown in Table 1. It was.

Comparative Example 1

The results are shown in Table 1, characterized in that the ethylene-alkyl (meth) acrylate copolymer (B) was not applied.

Comparative Example 2

The content of the diene graft copolymer (A) was used in less than 20 parts by weight, and the results are shown in Table 1.

Comparative Example 3

The content of the diene graft copolymer (A) in excess of 35 parts by weight of 42 parts by weight is used, and the sum of the contents of the diene graft copolymer (A) and the ethylene / alkyl (meth) acrylate copolymer (B) It was characterized by exceeding 45 parts by weight, the results are shown in Table 1.

Comparative Example 4

The branched vinyl cyanide compound-aromatic vinyl compound copolymer (c ₂ ) was replaced with (C) 10% by weight of the total content, and the remainder was replaced with the general chain-type vinyl cyanide compound-aromatic vinyl compound copolymer (c ₁ ). It is characterized in that the results are shown in Table 1.

The properties of the pellets and the specimens prepared according to the Examples and Comparative Examples were evaluated in the following manner. The results are shown in Table 1 below.

1) Notched Izod impact strength was measured according to ASTM D256 (1/8 ", 23 ° C).

2) Heat resistance (VST) was measured according to ISO R306 (5 kg, 120 ° C./hr).

3) The total occurrence time and the number of cracks were visually determined and the unit of time is minutes.

4) In order to evaluate chemical resistance and crack resistance, make a 3 mm hole in the tensile test specimen of ASTM standard, apply stress to forcibly increase the hole by using 4 mm diameter nails, and then completely immerse various organic solvents in the mixed solution. After the visual evaluation was carried out.

5) The extrusion stability was evaluated by measuring the appearance and circle eccentricity after molding a pipe having a diameter of 30 mm by using a profile extruder, and evaluated it as good case ○, somewhat poor case △, and very poor case ×.

Example Comparative Example One 2 3 4 One 2 3 4 (A) 31 31 33 31 32 18 42 31 (B) (b ₁ ) - 3 - - - - - - (b ₂ ) 3 - One 3 - 0.5 5 3 (C) (c ₁ ) 29 29 30 41 30 45 23 56 (c ₂ ) 37 37 36 25 38 36.5 30 10 Impact strength 58 57 52 55 49 31 54 54 Heat resistance 99 99 98 99 100 101 96 98 Sum of occurrence crack 0 0 2 One 9 19 0 5 Initial crack initiation time ∞ ∞ 45 200 Less than 1 Less than 1 ∞ 15 Extrusion moldability ○ ○ ○ ○ ○ △ ○ ×

From the results of Table 1, Examples 1 to 4 according to the present invention show fewer or fewer cracks than the Comparative Examples 1 to 4, and show a long crack generation time. In comparison between Example 1 and Example 2, physical properties or crack resistance when using ethylene-alkyl (meth) acrylate copolymer (B) directly synthesized with a commercialized product (b ₂ ) (b ₁ ) And no difference in chemical resistance was found. In addition, physical properties such as impact strength and heat resistance are also above a certain level.

Comparative Example 1, in which the ethylene-alkyl (meth) acrylate copolymer (B) was not applied in the comparison between Examples 1 to 4 and Comparative Example 1, was found to have crack resistance and crack resistance despite similar rubber content and impact strength. The chemistry was not good. This is an example showing that the ethylene-alkyl (meth) acrylate copolymer (B) is effective in improving chemical resistance and crack resistance.

In comparing Comparative Example 2 with Examples 1 to 4, Comparative Example in which the total content of the diene synthetic rubber (A) and the ethylene-alkyl (meth) acrylate copolymer (B) was less than the scope of the present patent. 2 was somewhat poor in extrusion moldability, and was not excellent in crack resistance and chemical resistance with low impact strength. This is an example showing that the scope of the present patent is effective in order to maintain proper chemical resistance and crack resistance.

On the contrary, Comparative Example 3 uses the total content of the diene synthetic rubber (A) and the ethylene-alkyl (meth) acrylate copolymer (B) in excess of the scope of the present patent, resulting in a very low heat resistance. This is an example showing that the application to parts exposed to temperature may be limited.

In the case of Comparative Example 4 in which the branched vinyl cyanide compound-aromatic vinyl compound copolymer (c ₂ ) was used less than the scope of the present patent, mechanical properties including impact strength were almost similar to those of Examples 1 to 4. However, the extrusion workability was poor, and the chemical resistance and crack resistance were somewhat unsatisfactory. This is an example showing that the branched vinyl cyanide compound-aromatic vinyl compound copolymer (c ₂ ), like the ethylene-alkyl (meth) acrylate copolymer (B), contributes greatly to the improvement of chemical resistance and crack resistance.

The present invention has the effect of the invention to provide a heat resistant ABS resin composition having excellent crack resistance and chemical resistance, good mechanical strength and excellent extrusion molding.

Simple modifications and variations of the present invention can be readily used by those skilled in the art, and all such variations or modifications can be considered to be included within the scope of the present invention.

Claims (8)

(A) 30 to 70% by weight of diene synthetic rubber; And 20 to 35 parts by weight of a diene graft polymer prepared by polymerizing 70 to 30% by weight of a monomer mixture comprising 20 to 30% by weight of a vinyl cyanide compound and 80 to 70% by weight of an aromatic vinyl compound. (B) 0.1 to 10 parts by weight of an ethylene-alkyl (meth) acrylate copolymer having a structure of formula (1): [Formula 1]

R ₁ is a hydrogen atom or a methyl group; R ₂ is a hydrogen atom or a C ₁ -C ₁₂ alkyl group which is an alkyl group of methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, t-butyl, isobutyl, isoamyl and t-amyl; m and n are degrees of polymerization, and the ratio of m and n is 300: 1 to 10:90; And (C) (c ₁ ) long-chain vinyl cyanide compound-aromatic vinyl compound copolymer, and (c ₂ ) branched vinyl cyanide compound-aromatic vinyl compound copolymer, wherein the content of (c ₂ ) 84.9 to 55 parts by weight of vinyl cyanide-aromatic vinyl compound copolymer, which is at least 20% by weight of C); Heat-resistant ABS resin composition, characterized in that consisting of. The method of claim 1, wherein the (C) vinyl cyanide-aromatic vinyl compound copolymer (c ₁ ) at least one type of long-chain vinyl cyanide compound-aromatic vinyl compound copolymer having a weight average molecular weight of copolymerization of 15 to 50% by weight of a vinyl cyanide compound and 85 to 50% by weight of an aromatic vinyl compound; And (c ₂ ) The weight average molecular weight of 15 to 50% by weight of the vinyl cyanide compound and 85 to 50% by weight of the aromatic vinyl compound in the presence of 0.001 to 0.05% by weight of the polyfunctional compound to the total (c ₂ ) 200,000 to 2,000,000 At least one branched vinyl cyanide compound-aromatic vinyl compound copolymer; Heat resistant ABS resin composition characterized by the above-mentioned. The heat resistant ABS resin composition according to claim 1, wherein the ethylene-alkyl (meth) acrylate copolymer (B) has a melt index of 0.01 to 40 g / 10 minutes at 190 ° C and 2.16 kgf. 2. The heat resistant ABS resin composition according to claim 1, wherein the diene synthetic rubber is manufactured using an average particle diameter of 0.1 to 1.0 mu m. The heat resistant ABS resin composition according to claim 1, wherein the diene-based synthetic rubber is manufactured using an average particle diameter of 0.2 to 0.8 mu m. The vinyl cyanide compound of the component (A) is selected from the group consisting of acrylonitrile and methacrylonitrile, wherein the aromatic vinyl compound of the component (A) is styrene, alpha-methylstyrene, Heat resistant ABS resin composition, characterized in that at least one selected from the group consisting of pt-butylstyrene, 2,4-dimethylstyrene and vinyltoluene. The cyanide compound of claim 1, wherein the cyanide compound of the vinyl cyanide compound-aromatic vinyl compound of the component (c ₂ ) is selected from the group consisting of acrylonitrile and methacrylonitrile, and cyanation of the component (c ₂ ). The aromatic compound vinyl compound of the vinyl compound-aromatic vinyl compound is at least one selected from the group consisting of styrene, divinylbenzene, alpha-methylstyrene, pt-butylstyrene, 2,4-dimethylstyrene and vinyltoluene. ABS resin composition. The polyfunctional compound of claim 2, wherein the multifunctional compound of component (c ₂ ) is divinylbenzene, aromatic vinyl compound, triaryl isocyanurate, polyfunctional mercaptan, and polyfunctional peroxide. Heat-resistant ABS resin composition, characterized in that the compound having a polyfunctional group selected from the group consisting of.