JPH04353552A - Thermoplastic resin composition - Google Patents

Abstract

PURPOSE:To obtain a thermoplastic resin composition having excellent impact resistance and chemical resistance by blending a rubber-reinforced graft copolymer with a specific unsaturated carboxylic acid alkyl ester based polymer and an epoxy group-containing olefin copolymer. CONSTITUTION:The objective thermoplastic resin composition obtaine by blending (A) 100 pts.wt. composition consisting of (A) 10-70wt.% graft copolymer (e.g. an ABS resin, an AES resin or an AAS resin) obtained by polymerizing a rubber based polymer with two or more kinds of compounds selected from an aromatic vinyl compound, a vinyl cyanide compound and an unsaturated carboxylic acid alkyl ester compound and (B) 90-30wt.% polymer consisting of B1: 50-100wt.% unsaturated carboxylic acid alkyl ester compound and B2: 0-50wt.% aromatic vinyl and/or vinyl cyanide and (C) 0.1-40 pts.wt. copolymer (preferably an ethylene-glycidyl methacrylate copolymer).

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic resin composition having excellent chemical resistance.

0002

[Prior art and problems] ABS resin (acrylonitrile-diene rubber-styrene polymer), AES resin (
Rubber-reinforced styrene resins such as acrylonitrile-ethylene/propylene rubber-styrene polymer), ACS resin (acrylonitrile-chlorinated polyethylene-styrene polymer), and AAS resin (acrylonitrile-acrylic rubber-styrene polymer) Due to its excellent balance between impact resistance and workability, it is used in fields such as vehicles, light electrical appliances, and miscellaneous goods.

However, these rubber-reinforced styrene resins have a problem in that they are inferior in chemical resistance compared to other engineering plastics and easily crack when they come into contact with gasoline, brake fluid, grease, etc.

It is already known that increasing the amount of vinyl cyanide (acrylonitrile) in a rubber-reinforced styrenic resin improves chemical resistance, but as the amount of acrylonitrile increases, impact resistance decreases. At the same time, initial coloring occurs, so there is a limit to the improvement of chemical resistance.

[0005]Also, the present applicant has already discovered that chemical resistance can be improved by blending a ternary copolymer consisting of an olefin, an unsaturated dicarboxylic acid anhydride, and an unsaturated carboxylic acid alkyl ester; With the diversification and functionalization of chemicals, there has been a desire to develop compositions with even better chemical resistance.

[0006] On the other hand, JP-A-59-89346 and JP-A-60-18536 disclose resin compositions with excellent matting effects, which are made by blending an epoxy group-containing olefin copolymer with ABS resin or AES resin. However, JP-A No. 57-139139 and JP-A No. 60-245
No. 662 describes resin compositions in which polymethyl methacrylate or methyl methacrylate-styrene-acrylonitrile terpolymer is blended with AES resin to improve color development. There is no description. Furthermore, JP-A-63-245
No. 461 describes a resin composition that has improved color development and chemical resistance by blending methyl methacrylate-styrene-acrylonitrile terpolymer with ABS resin, but the chemical resistance is still unknown. It was insufficient.

[0007]

[Means for Solving the Problems] As a result of extensive studies in order to obtain a resin composition with excellent chemical resistance, the present inventors added a specific unsaturated carboxylic acid alkyl ester type to a rubber-reinforced graft copolymer. The inventors have discovered that by blending specific amounts of a polymer and an epoxy group-containing olefin copolymer, a resin composition with excellent chemical resistance can be obtained without sacrificing impact resistance, and the present invention has been achieved.

That is, the present invention provides a graft copolymer obtained by polymerizing a rubbery polymer with two or more compounds selected from the group consisting of an aromatic vinyl compound, a vinyl cyanide compound, and an unsaturated carboxylic acid alkyl ester compound. Polymer (
A) 10-70% by weight and 50-100% by weight of unsaturated carboxylic acid alkyl ester compound and 0-50% by weight of aromatic vinyl compound and/or vinyl cyanide compound
Containing an epoxy group consisting of an unsaturated epoxy compound and an olefin or an ethylenically unsaturated compound and an unsaturated epoxy compound and an olefin, per 100 parts by weight of a composition consisting of 90 to 30 parts by weight of an unsaturated carboxylic acid alkyl ester polymer (B) consisting of The present invention provides a thermoplastic resin composition having excellent chemical resistance, characterized in that it contains 0.1 to 40 parts by weight of an olefin copolymer (C).

The present invention will be explained in detail below.

- Graft copolymer (A) - As the rubbery polymer in the graft copolymer (A), butadiene rubber such as polybutadiene, butadiene-styrene copolymer, butadiene-acrylonitrile copolymer, ethylene- Propylene copolymer, dicyclopentadiene, ethylidenenorbornene, 1,4-hexadiene, 1,4-
Ethylene-propylene rubber such as ethylene-propylene-non-conjugated diene copolymer obtained by copolymerizing non-conjugated dienes such as cycloheptadiene and 1,5-cyclooctadiene;
In the presence or absence of a crosslinking agent, an acrylic ester of an alkyl group having 1 to 16 carbon atoms, such as methyl acrylate, ethyl acrylate, butyl acrylate, 2
- Polymerization or copolymerization of one or more types of ethylhexyl acrylate and, if necessary, other copolymerizable monomers, such as one or more types of styrene, acrylonitrile, methyl methacrylate, etc. Examples include acrylic ester rubber. One type or two or more types can be used. These rubbery polymers can be produced by emulsion polymerization, solution polymerization, bulk polymerization, suspension polymerization, etc.

[0011] Examples of aromatic vinyl compounds include styrene,
α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, t-butylstyrene,
Examples include α-methylvinyltoluene, dimethylstyrene, chlorostyrene, dichlorostyrene, bromustyrene, dibromostyrene, etc., and one or more types can be used. Particularly preferred are styrene and α-methylstyrene.

Examples of vinyl cyanide compounds include acrylonitrile and methacrylonitrile, and one or more of them can be used. Acrylonitrile is particularly preferred.

Examples of unsaturated carboxylic acid alkyl ester compounds include methyl acrylate, ethyl acrylate,
Examples include butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, 2-ethylhexyl methacrylate, and one or more of them can be used. Particularly preferred is methyl methacrylate.

As the graft polymerization method, known methods such as emulsion polymerization, suspension polymerization, bulk polymerization, solution polymerization, or a combination thereof can be employed.

[0015] There is no particular restriction on the composition ratio of the rubber and the compound (total) to be subjected to graft polymerization, but the composition ratio of rubber 10 to 80
It is preferable that the compound (total) is 90 to 20 weight %, and there is no particular restriction on the composition ratio of each compound, but the aromatic vinyl compound 50 to 90 weight % and the vinyl cyanide compound and/or The amount of unsaturated carboxylic acid alkyl ester compound is preferably 10 to 50% by weight.

Furthermore, from the viewpoint of chemical resistance, the graft copolymer (A) is a graft copolymer (A-1) obtained by polymerizing a compound to an acrylic ester rubber, and a butadiene rubber or an ethylene-based rubber. Preferably, it is a mixture with a graft copolymer (A-2) obtained by polymerizing a compound into propylene rubber. These graft copolymers (A-
There is no particular restriction on the composition ratio of 1) and (A-2), but (A-1) 10 to 90% by weight and (A-2) 90 to 90% by weight.
Preferably it is 10% by weight.

The graft copolymer (A-2) is a butadiene rubber or an ethylene-propylene rubber selected from the group consisting of an aromatic vinyl compound, a vinyl cyanide compound, and an unsaturated carboxylic acid alkyl ester compound. A graft copolymer (A-2-1) obtained by polymerizing two or more compounds; and a graft copolymer (A-2-2) obtained by polymerizing two or more compounds selected from the above compound group.
It may be a mixture consisting of.

There is no particular restriction on the composition ratio of the graft copolymer (A-2-1) and the copolymer (A-2-2), but the ratio of the graft copolymer (A-2-1) to 10 to It is preferable that the content of the copolymer (A-2-2) is 100% by weight and 0 to 90% by weight of the copolymer (A-2-2).

[0019]Although there is no particular restriction on the composition ratio of each compound constituting the copolymer (A-2-2), 50 to 90% by weight of an aromatic vinyl compound and 10 to 10% by weight of a vinyl cyanide compound.
Preferably, it is 50% by weight and 0 to 40% by weight of the unsaturated carboxylic acid alkyl ester compound.

- Unsaturated carboxylic acid alkyl ester polymer (B) - The unsaturated carboxylic acid alkyl ester polymer in the present invention is an unsaturated carboxylic acid alkyl ester compound 5
It is a polymer consisting of 0 to 100% by weight and 0 to 50% by weight of an aromatic vinyl compound and/or a vinyl cyanide compound.

If the amount of the unsaturated carboxylic acid alkyl ester compound is less than 50% by weight, the chemical resistance will be poor and this is not preferred. From the physical property balance point of chemical resistance and impact resistance, the unsaturated carboxylic acid alkyl ester compound should be 50 to 95% by weight, the aromatic vinyl compound should be 5 to 50% by weight, and the cyanide vinyl compound should be 0 to 45% by weight. Preferably, the content of the unsaturated carboxylic acid alkyl ester compound is 50 to 90% by weight, the aromatic vinyl compound is 5 to 45% by weight, and the vinyl cyanide compound is particularly preferably 5 to 45% by weight.

The unsaturated carboxylic acid alkyl ester compounds, aromatic vinyl compounds and vinyl cyanide compounds constituting the above unsaturated carboxylic acid alkyl ester polymer (B) are listed in the section of the graft copolymer (A). The same ones mentioned can be used.

As a method for producing the unsaturated carboxylic acid alkyl ester polymer (B), known emulsion polymerization, suspension polymerization, solution polymerization, bulk polymerization, or a combination of these polymerization methods can be employed.

-Epoxy group-containing olefin copolymer (C
) - The epoxy group-containing olefin copolymer (C) used in the present invention is a copolymer consisting of an unsaturated epoxy compound and an olefin, or these and an ethylenically unsaturated compound. There is no particular restriction on the composition ratio of the epoxy group-containing olefin copolymer, but the unsaturated epoxy compound 0.0
It is preferably 5 to 95% by weight.

The unsaturated epoxy compound is a compound having an epoxy group and an unsaturated group copolymerizable with olefins and ethylenically unsaturated compounds in the molecule.

For example, unsaturated glycidyl esters, unsaturated glycidyl ethers, epoxy alkenes, P-
Unsaturated epoxy compounds such as glycidylstyrenes.

Specifically, glycidyl acrylate, glycidyl methacrylate, itaconic acid glycidyl esters, butene carboxylic acid esters, allyl glycidyl ether, 2-methylallyl glycidyl ether, styrene-P-glycidyl ether, 3,4-epoxybutene, 3,4-epoxy-3-methyl-1-butene, 3,4
-Epoxy-1-pentene, 3,4-epoxy-3-methylpentene, 5,6-epoxy-1-hexene, vinylcyclohexene monoxide, P-glycidyl styrene, etc., and one or more types may be used. Can be done. Glycidyl acrylate or glycidyl methacrylate is particularly preferred.

Examples of the olefin include ethylene, propylene, butene, and pentene, and one or more of them can be used. Particularly preferred are ethylene and propylene.

Examples of ethylenically unsaturated compounds include vinyl esters containing C2 to C6 as a saturated carboxylic acid component, acrylic and methacrylic esters and maleic esters containing C1 to C8 as a saturated alcohol component, and halogenated Examples include vinyls.

[0030] These ethylenically unsaturated compounds are used in an amount of not more than 50% by weight, particularly 0.1 to 45% by weight, based on the total compound during copolymerization of the unsaturated epoxy compound and olefin.
Copolymerized.

Epoxy group-containing olefin copolymer (C)
Copolymerize an unsaturated epoxy compound with an olefin and optionally an ethylenically unsaturated compound, or graft an unsaturated epoxy compound in the presence of an olefin polymer or a copolymer of an olefin and an ethylenically unsaturated compound. Manufactured by copolymerization.

[0032] Epoxy group-containing olefin copolymer (C)
Preferred examples include ethylene-glycidyl methacrylate copolymer, ethylene-vinyl acetate-glycidyl methacrylate copolymer, ethylene-methyl methacrylate-glycidyl methacrylate copolymer, and polyethylene, polypropylene, poly-1-butene, poly-4
Examples include copolymers obtained by grafting glycidyl methacrylate in the presence of an olefin polymer such as -methyl-pentene-1, ethylene-propylene copolymer, and ethylene-propylene-diene copolymer.

[0033] Epoxy group-containing olefin copolymer (C)
As a manufacturing method, an emulsion polymerization method, a suspension polymerization method, a bulk polymerization method, a solution polymerization method, or a polymerization method combining these methods is used.

The thermoplastic resin composition of the present invention comprises 100 to 70% by weight of the above-mentioned graft copolymer (A) and 90 to 30% by weight of the unsaturated alkyl carboxylic acid polymer (B). 0.1 to 40 parts by weight of the epoxy group-containing olefin copolymer (C) is blended.

If the graft copolymer (A) is less than 10% by weight (polymer (B) is more than 90% by weight), the impact resistance is poor, and if it exceeds 70% by weight (polymer (B) is more than 30% by weight)
% by weight), which is undesirable due to poor chemical resistance. Preferably, the content is 20 to 70% by weight of the graft copolymer (A) and 80 to 30% by weight of the unsaturated carboxylic acid alkyl ester polymer.

Epoxy group-containing olefin copolymer (C)
If it is less than 0.1 part by weight, the chemical resistance will be poor, and if it exceeds 40 parts by weight, it will tend to cause delamination, which is not preferable. Preferably it is 0.5 to 20 parts by weight.

There are no particular restrictions on the method of mixing the graft copolymer (A), the unsaturated carboxylic acid alkyl ester polymer (B), and the epoxy group-containing olefin copolymer (C), and they may be mixed in a latex state or as a powder. It can be mixed in the form of beads, pellets, etc.

[0038] As the melt-kneading method, known methods such as a Banbury mixer, roll, extruder, etc. can be employed.

[0039] At the time of mixing, additives such as antioxidants, ultraviolet absorbers, antistatic agents, lubricants, dyes, pigments, plasticizers, flame retardants, mold release agents, etc. can be added as necessary. In addition, thermoplastic resins such as olefin-unsaturated dicarboxylic anhydride-unsaturated carboxylic acid alkyl ester terpolymer, polyacetal, polycarbonate, polybutylene terephthalate, polyphenylene oxide, polymethyl methacrylate, polyvinyl chloride, etc. It is also possible to mix them.

Next, the present invention will be specifically explained with reference to Examples and Comparative Examples, but the present invention is not limited thereto. Note that all parts and percentages are expressed on a weight basis.

-Production of graft copolymer (A)-A-1
: 15 parts of acrylonitrile and 35 parts of styrene were copolymerized by emulsion polymerization in the presence of 50 parts (solid content) of cross-linked polybutyl acrylate latex with an average particle diameter of 0.3μ to obtain an AAS graft copolymer latex (grafting rate 50%). , a free acrylonitrile-styrene copolymer with an intrinsic viscosity of 0.36) was prepared.

A-2-1-1: average particle diameter 0.45μ,
50 parts of polybutadiene latex with a gel content of 83% (
15 parts of acrylonitrile and 35 parts of styrene were copolymerized by an emulsion polymerization method in the presence of solids (solid content) to produce an ABS graft copolymer latex (grafting rate 73%, intrinsic viscosity of free acrylonitrile-styrene copolymer 0.5).
1) was manufactured. Note that the intrinsic viscosity was measured in dimethylformamide at 30°C. (Unit: 100ml/g)

A-2-1-2: Ethylene-propylene-
Ethylidene norbornene copolymer (EPDM, iodine number 21, Mooney viscosity 75, propylene content 50%) 4
0 parts, AES graft copolymer consisting of 20 parts of acrylonitrile and 40 parts of styrene (grafting rate 52%, intrinsic viscosity of free acrylonitrile-styrene copolymer 0)
．． 61) was produced by a solution polymerization method.

A-2-2: An acrylonitrile-styrene copolymer consisting of 30 parts of acrylonitrile and 70 parts by weight of styrene was produced by a known emulsion polymerization method.

Graft copolymer A-1, A-2-1-1
and Copolymer A-2-2 each have a latex solid content of 1
After adding 1 part of Sumilizer NW and 2 parts of trinolylphenyl phosphite as antioxidants per 00 parts,
Salting out was performed using magnesium sulfate, and separation and recovery were performed. Graft copolymer A-2-1-2 was separated and recovered after precipitation in methanol.

- Unsaturated carboxylic acid alkyl ester polymer (B) - To 100 parts by weight of a mixture having the composition shown in Table 1, 0.4 parts by weight of t-dodecyl mercaptan (molecular weight regulator) and benzoyl peroxide (initiator) agent) After adding 0.3 parts by weight, polymerization was carried out at 80° C. for 8 hours based on a known suspension polymerization method using polyvinyl alcohol as a suspending agent. After dehydration, polymers B-1 and B-2 were obtained.

[0047]

[Table 1]

<PMMA> Polymethyl methacrylate “Sumipex MHO” manufactured by Sumitomo Chemical Co., Ltd.

-Epoxy group-containing olefin copolymer (C
) Production - Using an autoclave type polyethylene production apparatus, an epoxy group-containing olefin copolymer having the following composition was produced by bulk polymerization according to the polymerization conditions for high-pressure polyethylene.

C-1 Ethylene-glycidyl methacrylate-vinyl acetate copolymer (composition ratio 90-7-3) C
-2 Ethylene-glycidyl methacrylate copolymer (composition ratio 90-10)

Reference Example 3 - Production of olefin-unsaturated dicarboxylic acid anhydride-unsaturated carboxylic acid alkyl ester terpolymer (D) - Using a cylindrical autoclave equipped with a blade-type stirrer, a hydrocarbon distillate was produced. 185°C, 160atm in the presence of t-butyl 2-ethyl-perhexanoate dissolved in
Polymerize the monomer with 60% ethylene and maleic anhydride.
A terpolymer of 4.5% and 35.5% of ethyl acrylate was obtained.

Graft copolymer (A-
1, A-2-1-2), unsaturated carboxylic acid alkyl ester polymer (PMMA, B-1-2, b-2) and epoxy group-containing olefin copolymer (C-1-2) and The original copolymer was melt-kneaded with the composition shown in Table 2 to obtain a composition.

The physical properties of the obtained composition were measured by the following method. The results are shown in Table-2.

Izod Impact Strength ASTM D-256 1/4”t Notched Izod Impact Strength 23°C

Heat distortion temperature ASTM D-648 1/4”t 18.6
Kg/cm2 load No annealing

Chemical Resistance A test piece measuring 150 mm x 40 mm x 30 mm was prepared by injection molding, fixed in a 1/4 oval jig shown in FIG. 1, and then brake oil or gasoline was applied. The distance (h) from the minimum deflection point to the crack generation point is measured, and the critical strain (%) is determined based on the following formula.

[0057]

[Equation 1] a; 16cm b; 7.5cm h; Distance from the point of minimum deflection to the point of crack occurrence (
cm) t; Test piece thickness (0.3cm)

[0058]

[Table 2]

[Brief explanation of the drawing]

[Figure 1] 1/4 used to evaluate chemical resistance
It is a sectional view of an elliptical jig.

[Explanation of symbols]

1 1/4 oval jig 2 Minimum deflection point 3 Test piece a　Jig bottom length b Height of vertical part of jig

Claims (2)

[Claims] [Claim 1] Aromatic vinyl compound in a rubbery polymer,
10 to 70% by weight of a graft copolymer (A) obtained by polymerizing two or more compounds selected from the group consisting of a vinyl cyanide compound and an unsaturated carboxylic acid alkyl ester compound and an unsaturated carboxylic acid alkyl ester compound 5
Unsaturated carboxylic acid alkyl ester polymer (B) consisting of 0 to 100% by weight and 0 to 50% by weight of an aromatic vinyl compound and/or a vinyl cyanide compound (B) 90 to 30
per 100 parts by weight of the composition consisting of % by weight, an olefin copolymer containing an epoxy group (C
) 0.1 to 40 parts by weight of a thermoplastic resin composition. 2. The graft copolymer (A) comprises an acrylic ester rubber containing two or more compounds selected from the group consisting of an aromatic vinyl compound, a vinyl cyanide compound, and an unsaturated carboxylic acid alkyl ester compound. Graft copolymer (A-1) obtained by polymerization, butadiene rubber or ethylene-propylene rubber, and two types selected from the group consisting of an aromatic vinyl compound, a vinyl cyanide compound, and an unsaturated carboxylic acid alkyl ester compound. The thermoplastic resin composition according to claim 1, which is a mixture with a graft copolymer (A-2) obtained by polymerizing the above compounds.