JPS6044517A - Delustering thermoplastic resin composition - Google Patents

Abstract

PURPOSE:To provide titled composition in good moldability, capable of giving products of high impact strength and rigidity and uniform appearance, suitable for automobile inner parts or interior automotive trims, comprising each specific amount of rubbery polymer and ethylenic unsaturated carboxylic acid. CONSTITUTION:The objective composition comprising (1) 5-40 (pref. 5-30)wt% of rubbery polymer and (2) 0.3-3 (pref. 0.5-2)wt% of ethylenic unsaturated carboxylic acid can be obtained by blending, preferably, the following components: (A) a copolymer derived from monomer mixture consisting of (i) aromatic vinyl compound (e.g., styrene), (ii) vinylcyan compound (e.g., acrylonitrile), (iii) ethylenic unsaturated carboxylic acid (e.g., acrylic acid) and, if required, (iv) another compound copolymerizable with the above ones (e.g., acrylamide), (B) a rubber- modified thermoplastic resin (e.g., ABS resin) and, if required, (C) an aromatic vinyl (co)polymer.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rubber-modified thermoplastic resin composition that has excellent mechanical properties and moldability, and provides a matte surface of molded articles.

Rubber-modified thermoplastic resins have excellent impact resistance, moldability, and good surface gloss, and are therefore used for various purposes. However, depending on the intended use, it may be desirable to have a matte surface of the molded product without degrading other physical properties.

Applications that require such matte finish include automobile interior parts, office and household electrical equipment parts, and the like.

The conventional method for matting molded products is titanium.

A well-known method is to add oxides or carbonates such as magnesium and calcium to rubber-reinforced resins, but this method has the disadvantage of greatly reducing the mechanical properties of the resin, especially the impact strength, and also makes it less matte. However, the drawback is that the gloss on the surface of the molded product does not disappear uniformly.

A well-known method is to add a rubbery elastomer to a rubber-reinforced resin to eliminate luster.

This method reduces the mechanical properties of the resin, particularly its hardness and rigidity. Also, foreign matter appears on the surface of the molded product, significantly reducing the commercial value of the molded product.

Furthermore, a method of adding a three-dimensional resin component using a crosslinking monomer is also known, but this method has disadvantages such as uneven gloss on the surface of the molded product and reduced moldability.

The present inventors have solved the above-mentioned conventionally known technical problems of deterioration in impact resistance, rigidity, moldability, etc.

The present invention was achieved as a result of extensive research aimed at developing a matte rubber-reinforced thermoplastic resin that improves defects such as uneven gloss.

That is, the present invention is a rubber-modified vinyl aromatic thermoplastic resin composition, which contains 5 to 40% by weight of a rubbery polymer and 0% of a copolymerized ethylenically unsaturated carboxylic acid.
．． It is characterized by containing 3 to 3 parts by weight. A matte thermoplastic resin composition is provided.

As a constituent component of the composition of the present invention, a rubbery polymer (a
) in the presence or absence of a vinyl aromatic compound (
b) A copolymer obtained by polymerizing a monomer mixture consisting of a vinyl cyanide compound (C), an ethylenically unsaturated carboxylic acid (d), and, if necessary, a compound (e) that can be copolymerized with these. (5).

As the rubbery polymer (a), diene rubbery polymers and non-diene rubbery polymers can be used.

Polybutadiene is an example of a diene-based rubbery polymer.

Natural rubber, styrene-butadiene copolymer (8BR),
Examples include acrylonitrile-butadiene copolymer (NBR), polyisoprene, and polychloroprene. These rubber-like polymers are produced by emulsion polymerization, solution polymerization, etc. Polybutadiene, polyisoprene, 8BR coupled with tin or lithium, and styrene-butadiene block copolymers can also be used. can. These rubbery polymers can be used alone or in combination of two or more.

On the other hand, non-diene rubbery polymers include ethylene-propylene copolymer, ethylene-propylene-non-conjugated diene co-tetrapolymer, and chlorinated polyethylene.

Examples include acrylic rubber-like polymers. These non-diene rubbery polymers can be used alone or in combination of two or more. It is also possible to use a mixture of a diene rubbery polymer and a non-diene rubbery polymer.

Vinyl aromatic compounds (b) include: styrene, α-methylstyrene lO-methylstyrene 1m-methylstyrenyl-methylstyrene-α-ethylstyrene, methyl-α-methylstyrene-dimethylstyrene, dimethylstyrene, dimethylstyrene, Sostyrene.

Bromstyrene, dibromstyrene, vinylnaphthalene, etc. are mentioned. Preferred monomers are styrene, α-
It is methylstyrene.

As the vinyl cyanide compound (C), acrylonitrile,
Examples include methacrylate trile.

Examples of the ethylenically unsaturated carboxylic acid (d) include acrylic acid, methacrylic acid, ethacrylic acid, itaconic acid, maleic acid, and fumaric acid. Preferred monomers are acrylic acid and methacrylic acid.

Compounds copolymerizable with the above monomers (e) 2 For example, compounds having an amide group, dilambda compounds, N-methylol compounds, ethylenically unsaturated carboxylic acid esters, polyfunctional monomers, etc. can be used. .

Examples of compounds having an amide group or N-methylol compounds include acrylamide-methacrylamide,
Examples include N-methylol acrylamide. Examples of the ethylenically unsaturated carboxylic acid ester compound include p-alkyl acrylate-alkyl methacrylate and tohydroxyalkyl ethylenically unsaturated carboxylic acid ester.

Examples of the alkyl acrylate include methyl acrylate and ethyl acrylate. Examples of the alkyl methacrylate include methyl methacrylate and ethyl methacrylate. Examples of the human tetraxyalkyl ester of ethylenically unsaturated carboxylic acid include β-human tetraxyethyl acrylate and β-hydroxyethyl methacrylate. Examples of polyfunctional monomers include divinylbenzene.

Preferred embodiments of the present invention are listed below.

(1) In the presence of the rubbery polymer (a), a vinyl aromatic compound (b), a vinyl cyanide compound (C), an ethylenically unsaturated carboxylic acid (d), and, if necessary, a compound copolymerizable with these. A composition comprising a graft copolymer (5) obtained by polymerizing a monomer mixture (f) comprising (e).

(2) A monomer mixture (f) consisting of a vinyl aromatic compound (b), a vinyl cyanide compound (C), an ethylenically unsaturated carboxylic acid (d) and, if necessary, a compound copolymerizable with these (e). ) and a rubber-modified thermoplastic resin (B);
A'), (B) and vinyl aromatic copolymer (q
A composition consisting of

(3) The above (5) is an essential component, and (A') (
A composition comprising B) and at least one of (q).

(4) A composition comprising (A') as an essential component and at least one of (5) and (B).

Among these compositions, more preferable ones are (2) and (3).
), (4), and (2) is particularly preferred.

The graft copolymer (5) or copolymer (A')
is emulsion polymerization, suspension polymerization, or solution polymerization of the monomer mixture (f) in the presence or absence of the rubbery polymer (a).

It can be obtained by bulk polymerization or a combination of these polymerization methods.

In addition, as the rubber-modified thermoplastic resin (B), for example, acrylonitrile-butadiene-styrene copolymer (ABS
resin), acrylonitrilubutadienystyrene-α
-Methylstyrene copolymers and copolymers containing methyl methacrylate (heat-resistant ABS resins), acrylonitrile-ethylene/α monoolefin-styrene copolymers (ABS resins), acrylonitrile-butyl acrylate-styrene copolymers (ASA resin), methyl methacrylate-butadiene-styrene copolymer (M
B8 resin), rubber modified polystyrene (HIPf9 resin)
, polycarbonate resin and ABS resin, or a mixed resin of ABS resin, and a flame-retardant resin that combines ABS resin with vinyl chloride resin.

and flame-retardant ABS resin, which is a mixture of ABS resin with a flame retardant. Among the rubber-modified thermoplastic resins, those containing vinyl aromatic monomers and vinyl cyanide compound monomers are particularly preferred.

vinyl aromatic system) polymer (Q is a polymer of the vinyl aromatic compound (b) alone, or a polymer of the vinyl aromatic compound (b), a vinyl cyanide compound (C), and the copolymerizable compound (Q). Examples include copolymers with at least one selected from d).

In the composition of the present invention, the rubbery polymer (a
) content is 5 to 40% by weight, preferably 5 to 3% by weight.
It is 0% by weight.

Further, the content of ethylenically unsaturated carboxylic acid in the composition is 0.3 to 3% by weight, preferably 0.5 to 2% by weight.

The content of the vinyl aromatic compound (b) in the composition is preferably 54.7 to 90% by weight, more preferably 59% by weight.
．． The content of the vinyl cyanide compound (C) is preferably 4.7 to 40% by weight, more preferably 4.5 to 35% by weight, and the content of the vinyl cyanide compound (C) is preferably 4.5 to 35% by weight. ) is preferably 20% by weight or less.

More preferably, it is 0 to 10% by weight.

The rubbery polymer contributes to improving impact resistance, and if it is too small, impact resistance cannot be obtained, while when it is too large, the hardness decreases and its uses are restricted.

What is the content of ethylenically unsaturated carboxylic acid monomer?

If the amount is less than 0.3% by weight, the matting effect will not be sufficient.

Moreover, if it exceeds 3.0% by weight, uneven gloss will occur on the surface of the molded product, resulting in an uneven matte state, which is not preferable.

The content of vinyl cyanide compounds contributes to improving impact resistance and chemical resistance. If the content is too low, it will cause a decrease in impact resistance and chemical resistance, which is undesirable. On the other hand, if it is too high, it will cause a decrease in processability and two color tones. Undesirable.

The content of the vinyl aromatic compound contributes to the moldability, and if the content is too low, the moldability will deteriorate, which is undesirable, while if the content is too high, the amount of the vinyl cyanide compound monomer used will decrease, resulting in the unfavorable behavior described above.

As for the graft copolymer (5), the component ratio (wt%) of the rubbery polymer and the monomer mixture (f) in the two particles is preferably 5 to 60/95 to 40, more preferably 5 to 60/95 to 40.
It is 40/95-60.

Also, the composition ratio of monomer mixture Cf) (total 100 weight)
The ratio of vinyl aromatic compound (b)/vinyl cyanide compound (C)/ethylenic unsaturated carboxylic acid (d)/other copolymerizable compound (e) is 30 to 92.68/
7-4010.32-3010-25 are preferred.

More preferably 45-89.47/10-3510.5
3-2010-15.

Further, as for the copolymer (A'), the composition ratio of the monomer mixture (f) constituting the copolymer (A') is vinyl aromatic compound (b)/vinyl cyanide compound (C)/ethylenic inorganic compound. The ratio of saturated carboxylic acid (d)/other copolymerizable compound (e) (total 100% by weight) is 30 to 92.6/7 to 40
10.4-3010-25 is preferable, more preferably 45-89.5/10-3510.5-2010-15
It is.

If the content of ethylenically unsaturated carboxylic acid in the above (5) or (A') is too small, a sufficient matting effect cannot be obtained,
On the other hand, if the amount is too large, the miscibility with the rubber-modified thermoplastic resin decreases.

In addition, the above copolymer (5), (the intrinsic viscosity of the methyl ethyl ketone (MEK) soluble portion of A2 piece [η) (MHK 30°C)
is preferably 0.3 to 0.8 di/11, and 0.3 cL
If it is less than tff/, f, the matting effect will not be sufficient, or if it is less than 0
,8d7! If /I is exceeded, the matte state of the molded product will become uneven, which is not preferable.

The copolymer of the present invention is a resin that alone has matte properties. It can also be blended with other resins such as polyphenylene oxide, vinylidene fluoride resins, nylon, polyacetal, etc., and has a matting effect, but especially in the above-mentioned vinyl aromatic resins). A substance has excellent properties.

That is, the resin composition according to the present invention maintains its high impact strength and rigidity, and can obtain a good matting effect without causing uneven gloss on the surface of the molded product, and can be used as an interior material for automobile internal parts and interior materials. It can be used for household and business electrical equipment parts, etc.

Furthermore, the resin composition of the present invention provides good matte molded products not only by injection molding but also by extrusion molding, vacuum molding, etc., and has extremely high industrial utility value.

Next, the present invention will be explained in more detail based on Examples and Comparative Examples, but the present invention is not limited by the Examples unless the gist of the invention is exceeded.

(solid content: 58 parts), 250 parts of water, and 10 parts of potassium oleate, and 0.2 parts of sodium pyrophosphate.

Dextrose 0.2 parts, ferrous sulfate 0.004 parts-'
Add 0.4 part of cumene hydroperoxide.

A mixture of each monomer shown in Table 1 (80 parts in total) and 0.3 part of t-dodecylmercaptan was added dropwise to the reactor while stirring under a nitrogen stream. The dropwise addition time was 2 hours, and the polymerization temperature was 60°C. The resulting resin latex was coagulated, dried, pelletized, and subjected to injection molding. The evaluation results are shown in Table 1.

From Table 1, it can be seen that the resin composition of the present invention has good impact resistance and the gloss of the molded product disappears uniformly.

On the other hand, if the amount of unsaturated carboxylic acid is small, no matting effect will be obtained, and if it is in excess, the gloss will decrease, but
Uneven gloss occurs on the surface of the molded product, resulting in an uneven matte state.

Table 1 (1) Impact value: ASTM (D256-54T) Notched Izot 23°C (2) Surface gloss: Digital bending gloss meter U manufactured by Suga Test Instruments Co., Ltd.
Reflected light was measured at an incident angle of 60° using GV-4D.

(3) Surface appearance: A molded article having a thickness of 150 mm x 150 mm and a thickness of 30 mm was molded using an 8-ounce injection molding machine, and its surface appearance was visually evaluated. ○ indicates that the surface is uniform with no uneven gloss, and × indicates that the surface has significant uneven gloss and roughness.

Example 2 Method for producing a copolymer - Process 300 parts of deionized water and 2 parts of sodium dodecylbenzenesulfonate into a reactor equipped with a stirrer.

1/3 of the monomers listed in Table 2 were added. After thorough emulsification, the two reactors were heated and when the temperature reached 65°C, 0.1 part of potassium persulfate was added. After 1 hour and 2 hours from this time, 1/3 of the monomers shown in Table 2 and 0.05 parts of potassium persulfate were added, and polymerization was carried out for a total of 3 hours.

The resulting resin latex was coagulated to produce carboxylic acid-containing copolymers (a), (b), (c), and (ii).

The copolymers shown in Table 2 were mixed with various rubber-reinforced resins as shown in Table 3, pelletized, and injection molded for evaluation. Each resin listed in Table 3 is as follows.

ABS resin-1: ABS resin consisting of 20 parts of polybutadiene rubber, 54 parts of styrene, and 26 parts of acrylonitrile ABS resin ABS resin; EPT (JSRE manufactured by Japan EP Rubber Co., Ltd.
P-24) AFiS resin consisting of 20 parts of acrylonitrile, 50 parts of methylene fluoride, AASAs resin consisting of 25 parts of butyl acrylate polymer, 50 parts of styrene, and 25 parts of acrylonitrile. ) Polycarbonate resin; Tubarex 7o22 (Mitsubishi Kasei ■M) The method for evaluating the prepared composition was the same as that described in Example 1.

As can be seen from Table 3, each rubber-reinforced thermoplastic resin containing 0.5 to 3.0% by weight of ethylenically unsaturated carboxylic acid reduces the gloss of the surface of the molded product and causes uneven surface gloss. It is evenly matted without any scratches.

On the other hand, if the amount of ethylenically unsaturated carboxylic acid is small, a sufficient matting effect cannot be obtained, and if it is excessive, uneven gloss will occur in the molded product, making it unsuitable for practical use.

Table 2 Example 3 The copolymer (a) in Table 2 was mixed with the following self-extinguishing resin, injection molded, and evaluated.

Self-extinguishing resin (1) 25 parts of polybutadiene rubber, 55 parts of styrene.

40 parts of ABS resin consisting of 20 parts of acrylonitrile and 60 parts of vinyl chloride resin were mixed.

Self-extinguishing resin (2) 20 parts of polybutadiene rubber, 75 parts of ABS resin consisting of 57 parts of styrene and 23 parts of acrylonitrile, 21 parts of a flame retardant (tetrabromobisphenol A), and 4 parts of antimony trioxide were mixed.

The blending amounts and evaluation results are shown in Table 4.

Table 4 As can be seen from Table 4, the same effects described in Examples 1 and 2 can be obtained with self-extinguishing resins.

Patent applicant: Japan Synthetic Rubber Co., Ltd. Procedural amendment (spontaneous) November 10, 1981 1. Indication of case: Japanese Patent Application No. 58-151387 2. Title of invention: Matte thermoplastic resin composition 3: Amended. Patent applicant address: 4, 2-11-24 Tsukiji, Chuo-ku, Tokyo, "Detailed description of the invention" column 5 of the specification subject to amendment, Contents of the amendment: Details of the amendment as shown in the attached sheet. (1) Page 7, line 18: “...it is something to be gained.”
Insert the following sentence after .

"Also, in order to adjust the pH of the polymerization system, it is also possible to add ethylenically unsaturated carboxylic acid after neutralizing it with a base, and after the polymerization is complete, add a mineral acid to return it to carboxylic acid." (2 ) Page 11, line 17 r After "(MEK 30°C) is", insert "0.3 to 1, preferably Odi/g, particularly".

(3) Page 11, line 18, r 0.8 dl/g J is corrected to [1, Odl/gJ.

(4) Page 13, line 9, after "stirred and added dropwise.""The ethylenically unsaturated carboxylic acid was neutralized with caustic potash and added.' Ji insertion + 5° (5) No. 13
Page 10-12 lines [The resultant product was subjected to injection molding. ``The resulting resin latex was coagulated with sulfuric acid, and at the same time, the carboxylic acid salt was converted back to carboxylic acid.The resulting resin was dried, pelletized, and subjected to injection molding.'' ] Correct.

that's all =137

Claims (1)

[Claims] A rubber-modified vinyl aromatic thermoplastic resin composition,
A matte thermoplastic resin composition comprising 5 to 40% by weight of a rubbery polymer and 0.3 to 3% by weight of a copolymerized ethylenically unsaturated carboxylic acid.