JPH07195599A - Synthetic resin composite body - Google Patents

Abstract

PURPOSE:To manufacture a synthetic resin composite body which has a superior resistance to environmental stress cracking, is suitable as a heat insulating material, vibration-damping material, a sound insulating material and the like. CONSTITUTION:A synthetic resin composite body is composed of a molded body of a thermoplastic resin composition containing the following (1) and (2) and a urethane foamed body. (1) Rubber-containing styrene resin of 100 wt. pts. containing conjugated diene rubber [B] of 2-40et.%, an unsaturated nitrile component of 20-50wt.% and an aromatic vinyl component of 10-78wt.%, and the rubber-containing styrene resin is composed of graft [G[ of 5-50wt.% and matrix resin [M[ of 50-95wt.% Graft superstrate [GM] of [C] is graft polymerized with [B], and the graft superstrate [GM] is a copolymer containing an unsaturated nitrile monomer of 20-25wt.% and an aromatic vinyl monomer of 65-80wt.%, and [M] is a copolymer containing unsaturated nitrile monomer of 35-50wt.% and the aromatic vinyl monomer of 50-65wt.%. (2) Acryl rubber of 1-100 pts.wt.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synthetic resin composite composed of a molded product of a thermoplastic resin composition comprising a specific rubber-containing styrene resin and acrylic rubber and a urethane foam. More specifically, a rubber-containing styrene resin and an acrylic rubber in which a graft branch constituting a rubber-containing styrene resin, a matrix resin, and an unsaturated nitrile component content and an aromatic vinyl component content of the rubber-containing styrene resin are specified. A synthetic resin composite having a heat insulating property, a vibration damping property, and a sound insulating property, which is composed of a molded product of a thermoplastic resin composition having improved environmental stress crack resistance and molding processability and a urethane foam. Regarding

[0002]

AB representing rubber-containing styrene resin
BACKGROUND ART A synthetic resin composite composed of a molded product of S (acrylonitrile-butadiene-styrene) resin and a urethane foam is known, and is widely used as a heat insulating material in household refrigerators and the like. Such a synthetic resin composite is produced by reacting a mixture containing a polyisocyanate, a polyol and a foaming agent as main components in the presence of an ABS resin molding,
Fluorocarbon, that is, chlorofluorocarbon, is widely used as a foaming agent.

However, in the synthetic resin composite thus obtained, cracks may occur in the ABS resin molded body due to the environmental stress cracking phenomenon. It is believed that the cause is that chlorofluorocarbon used as a foaming agent for urethane, together with the tensile stress applied to the ABS resin molded body during the manufacturing process or during the use of the synthetic resin composite, causes environmental stress crack fracture. .

By the way, it has been pointed out that certain CFCs such as CFC11 currently used as a foaming agent are suspected as a substance causing the greenhouse effect of the global environment or a substance causing the destruction of the ozone layer. It is planned and the use of alternative CFCs with less potential for environmental damage is planned. However, CFC 123 or CFC 14 which is an alternative CFC that is planned to be used as a foaming agent.
1b has a greater effect on the environmental stress crack fracture of the ABS resin than CFC 11, and therefore CFC 11 was used in the synthetic resin composite manufactured using CFC 123 or CFC 141b as the foaming agent. The ABS resin molded body is more likely to crack than the synthetic resin composite.

For the purpose of preventing environmental stress cracking due to CFCs, the thickness of the ABS resin molded body forming the synthetic resin composite is increased, or a polyethylene film layer is formed at the interface between the ABS resin molded body and the urethane foam. However, since it is not economical, it is desired to develop a synthetic resin composite using an ABS resin molded product having improved environmental stress crack resistance.

For the purpose of improving the environmental stress cracking resistance of the synthetic resin composite, the molecular weight of the AS (acrylonitrile-styrene) resin which constitutes the resin component of the ABS resin used is increased, or the polar simple substance which constitutes the AS resin is increased. Increase the composition ratio of acrylonitrile, which is a monomer, or
Although a method of copolymerizing a polar monomer other than acrylonitrile with an S resin is known, these methods are accompanied by a decrease in molding processability of the ABS resin and cause practical inconvenience in producing an ABS resin molded body. Not only did it occur, but the effect of improving the environmental stress crack resistance was insufficient.

As a method for improving the environmental stress crack resistance of rubber-containing styrene resin such as ABS resin, the present inventors have already proposed a thermoplastic resin composition comprising a rubber-containing styrene resin and a specific acrylic rubber. (Japanese Patent Publication Sho 63-22
222, JP-B-63-28445, JP-B-63-28460, JP-B-63-54303, JP-B2-1857, and JP-B-3-52783.
Japanese Patent Publication No. 3-54984). However, these inventions did not optimize the improvement of the environmental stress crack resistance against the alternative CFCs. Further, no means has been proposed for achieving both improved environmental stress crack resistance against alternative CFCs and good molding processability, which is inconvenient for practical use as a rubber-containing styrene resin molded product that constitutes a synthetic resin composite. was there.

[0008]

The rubber-containing styrenic resin used in the thermoplastic resin composition constituting the synthetic resin composite as described above has an improved environmental stress crack resistance against alternative CFCs and a favorable molding process. Improvement of sex was desired. The present invention solves these problems and provides an economically superior synthetic resin composite.

[0009]

The present invention is composed of a rubber-containing styrene resin and an acrylic rubber which are controlled in a specific composition range, and is excellent in environmental stress crack resistance against alternative CFCs, and at the same time has good moldability. And a synthetic resin composite composed of a urethane foam and a molded body of a thermoplastic resin composition. That is, the present invention is a synthetic method comprising a molded body of a thermoplastic resin composition containing 100 parts by weight of a rubber-containing styrene resin having the following characteristics and 0.1 to 100 parts by weight of an acrylic rubber, and a urethane foam. It is a resin composite. The rubber-containing styrene resin is (a)
The graft copolymer [G] is composed of 5 to 50% by weight and the matrix resin [M] is 50 to 95% by weight, and (b) the graft copolymer [G] is a monomer of unsaturated nitrile in the conjugated diene rubber [B]. Is a copolymer obtained by graft-copolymerizing a graft branch [GM] composed of a copolymer of a polymer and two or more kinds of monomers including an aromatic vinyl monomer, and the graft branch [GM] is a monomer of an unsaturated nitrile. Is a copolymer of two or more monomers containing 20 to 35% by weight of the aromatic vinyl monomer and 65 to 80% by weight of the aromatic vinyl monomer, and (c) the matrix resin [M] is an unsaturated nitrile monomer. 35-50% by weight and aromatic vinyl monomer 50-
A copolymer of two or more monomers containing 65% by weight,
And, the conjugated diene rubber [B] component in the rubber-containing styrene resin (d) is 2 to 40% by weight, the unsaturated nitrile component is 20 to 50% by weight, and the aromatic vinyl component is 10 to 7%.
It is characterized by containing 8% by weight.

The rubber-containing styrene resin used in the thermoplastic resin composition constituting the synthetic resin composite of the present invention is
The conjugated diene rubber [B] contains an unsaturated nitrile component and an aromatic vinyl component. The conjugated diene rubber [B] in the present invention means a single weight of a conjugated diene monomer such as butadiene, isoprene or chloroprene. Polymers or copolymers, unsaturated nitrile components are polymers of unsaturated nitrile monomers such as acrylonitrile and methacrylonitrile, and aromatic vinyl components are styrene, α-methylstyrene, vinyltoluene, t-butylstyrene, It shows that it is a polymer of an aromatic vinyl monomer such as bromostyrene.

The rubber-containing styrene resin used in the present invention comprises a graft copolymer [G] and a matrix resin [M], and the graft copolymer [G] is grafted onto a conjugated diene rubber [B]. [GM] is graft-copolymerized, the graft branch [GM] is a copolymer containing an unsaturated nitrile monomer and an aromatic vinyl monomer, and the matrix resin [M] is different from the graft branch [GM]. It is a copolymer containing an unsaturated nitrile monomer having a composition and an aromatic vinyl monomer.

The rubber-containing styrenic resin used in the present invention comprises a graft copolymer [G] which constitutes a dispersed phase and a matrix resin [M] which constitutes a continuous phase. In addition, a method of carrying out emulsion radical polymerization by adding a necessary amount of an unsaturated nitrile monomer and an aromatic vinyl monomer to the presence of a conjugated diene rubber [B] latex produced by emulsion polymerization is generally performed industrially. Be seen. It is also known to add a separately produced matrix resin to the rubber-containing styrene resin obtained by such a production method. In the present invention, the rubber-containing styrene resin can be manufactured by such a method, but the manufacturing method is not particularly limited.

The rubber-containing styrene resin used industrially is a conjugated diene rubber [B] and a graft branch [GM] for the purpose of improving properties such as rigidity, heat resistance, impact resistance and molding processability. Alternatively, during the production of the matrix resin [M], it is generally carried out that a monomer other than the above-mentioned monomer is added to the above-mentioned monomers shown as the monomers constituting these polymers and copolymerized. However, examples of such a monomer include (meth) acrylic acid, methyl (meth) acrylate,
Ethyl (meth) acrylate, butyl (meth) acrylate, octyl (meth) acrylate, decyl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, etc. Examples include monomers, maleimides, N-butylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide and other maleimide-based monomers, (meth) acrylamide, maleic anhydride and the like.

The rubber-containing styrene resin used in the present invention comprises (a) 5 to 50% by weight of the graft copolymer [G] and 50 to 95% by weight of the matrix resin [M],
(B) The graft copolymer [G] is a graft branch [B] composed of a copolymer of two or more kinds of monomers including an unsaturated nitrile monomer and an aromatic vinyl monomer on a conjugated diene rubber [B]. GM] is a copolymer obtained by graft copolymerization, and the graft branch [GM] is an unsaturated nitrile monomer of 20 to 35% by weight.
And an aromatic vinyl monomer in an amount of 65 to 80% by weight, and (c) the matrix resin [M] is an unsaturated nitrile monomer in an amount of 35 to 50% by weight. It is a copolymer of two or more monomers containing 50 to 65% by weight of an aromatic vinyl monomer, and (d) the conjugated diene rubber [B] component in the rubber-containing styrene resin has 2 to 2 parts. 40% by weight, the unsaturated nitrile component is 20 to 50% by weight, and the aromatic vinyl component is 10 to 78% by weight. These constituents are conditions for the synthetic resin composite of the present invention to have practically preferable environmental stress crack resistance and molding processability.

In order to improve the environmental stress crack resistance of the rubber-containing styrenic resin against the CFC substitute, the unsaturated nitrile component constituting the rubber-containing styrenic resin is disclosed, for example, in JP-A-5-155949. However, as the composition ratio of the unsaturated nitrile component increases, the melt viscosity of the resin increases, and industrially undesirable molding processability decreases. However, according to the findings of the present invention, when increasing the composition ratio of the unsaturated nitrile component constituting the rubber-containing styrene resin,
If the unsaturated nitrile component of the graft branch [GM] is suppressed to a low level and the unsaturated nitrile component of the matrix resin [M] is increased, a thermoplastic resin composition having high environmental stress crack resistance and good moldability is obtained. It is obtained and suitably used for a synthetic resin composite. That is, the rubber-containing styrene resin used in the present invention is inferior in environmental stress crack resistance when the unsaturated nitrile component is less than 20% by weight, and inferior in moldability when it exceeds 50% by weight. Further, if the unsaturated nitrile monomer of the graft branch [GM] constituting the rubber-containing styrene resin graft copolymer [G] used in the present invention exceeds 35% by weight, the moldability becomes poor. Further, if the unsaturated nitrile monomer of the matrix resin [M] is less than 35% by weight, environmental stress crack resistance is poor, and if it exceeds 50% by weight, moldability is poor.

In order to produce a rubber-containing styrenic resin in which the graft branch [GM] and the matrix resin [M] have different compositions, an unsaturated nitrile monomer and an aroma which are polymerized in the presence of a diene rubber [B] are used. There is a method of sequentially changing the composition ratio of the vinyl monomer of the group, a method of blending a rubber-containing styrene resin with a matrix resin having a different composition, and the like, but the manufacturing method is not limited.

The acrylic rubber used in the thermoplastic resin composition constituting the synthetic resin composite of the present invention is a homopolymer or copolymer of a (meth) acrylic acid ester-based monomer. Is the above-mentioned unsaturated nitrile monomer,
Aromatic vinyl monomers, maleimide monomers, (meth) acrylamide, maleic anhydride, olefin monomers such as ethylene, propylene, 1-butene, isobutylene and 2-butene, and fatty acid vinyl such as vinyl acetate There are monomers, etc.

It is known to use a graft-polymerized acrylic rubber for the purpose of improving the compatibility between the acrylic rubber and the rubber-containing styrene resin (Japanese Patent Publication Sho 63-2).
No. 8445, Japanese Patent Publication No. 63-28460).
The acrylic rubber used in the present invention may be the acrylic rubber having a graft branch disclosed in the publication.

The acrylic rubber used in the present invention preferably has a glass transition temperature of 20 ° C. or lower. When the glass transition temperature exceeds 20 ° C, the environmental stress crack resistance of the thermoplastic resin composition is insufficient. When the acrylic rubber has graft branches, the glass transition temperature of the acrylic rubber means the glass transition temperature of the trunk polymer that does not contain graft branches.

The thermoplastic resin composition used in the present invention can be obtained by containing a rubber-containing styrene resin and an acrylic rubber, but the production method is arbitrary. For example, when both the rubber-containing styrene resin and the acrylic rubber are produced by emulsion polymerization, the obtained polymer latex can be mixed according to the method described in JP-B-63-22222. The acrylic rubber composition preliminarily mixed in the emulsified state according to the method described in JP-B-3-52783 can also be melt-kneaded with a rubber-containing styrene resin separately. In addition, a method of mixing an acrylic rubber latex with a rubber-containing styrene resin solid is also possible by utilizing the method disclosed in Japanese Patent Publication No. 59-15942. When the rubber-containing styrene resin and the acrylic rubber are both solid, they can be melt-mixed by a melt-mixing device such as a screw extruder or a Banbury mixer.

The thermoplastic resin composition used in the present invention comprises 100 parts by weight of a rubber-containing styrene resin and 0.1% of acrylic rubber.
When the content of acrylic rubber is less than 0.1 part by weight, the resulting thermoplastic resin composition has insufficient resistance to environmental stress cracking, and when it exceeds 100 parts by weight. Not only is the effect saturated, but the properties such as heat resistance, rigidity, and gloss of the thermoplastic resin composition deteriorate, which is not desirable. When the acrylic rubber has a graft branch, the content of the acrylic rubber means the content of the trunk polymer containing no graft branch.

The thermoplastic resin composition used in the present invention can be used as a mixture with other polymer materials for the purpose of improving properties such as impact resistance, heat resistance, rigidity and flame retardancy. Such polymer materials are SBR (styrene-butadiene rubber), EPR (ethylene-propylene rubber), NBR.
Elastomers such as (acrylonitrile-butadiene rubber), polyolefins such as polyethylene and polypropylene, polyamides such as nylon 6, nylon 66, nylon 610, nylon 612, nylon 11 and nylon 12, polyesters such as polyethylene terephthalate and polybutylene terephthalate, polycarbonates, Acrylic resin, polyvinyl chloride, etc. are available.

The synthetic resin composite of the present invention is produced by reacting a mixture containing a polyisocyanate, a polyol and a foaming agent as main components in the presence of a preformed thermoplastic resin composition molding. The composition and manufacturing method of the urethane foam of the present invention are not particularly limited.

Specific examples of the polyisocyanate used for producing the urethane foam are tolylene diisocyanate, o
-Tolidine diisocyanate, diphenylmethane-4,
4'-diisocyanate, 1,3-xylylene diisocyanate, naphthylene-1,5-diisocyanate, 1
-Methylcyclohexane-2,4-diisocyanate and the like. Specific examples of the polyol include 1,4-butanediol, ethylene glycol, polyethylene glycol,
Propylene glycol, polypropylene glycol, poly (ethylene oxide-propylene oxide) copolymer, α, ω-polycaprolactone diol, α, ω-
Diols such as polybutadiene diol, glycerin,
There are triols such as trimethylolpropane, pentaerythritol, methylglycoside, sorbitol, sucrose and the like, and addition products of ethylene oxide or propylene oxide with these polyols. Examples of the foaming agent include CFC 11, CFC 12, CFC 113, CFC 123, CFC 141b, and methylene chloride.

In the production of urethane foam, it is known to use water, which acts as a chemical blowing agent, an organic tin compound, a catalyst typified by tertiary amines, and a surfactant, which acts as a bubble stabilizer. Although a number of techniques for using these have been disclosed, the urethane foaming formulation is not particularly limited in the present invention.

[0026]

The present invention will be described in more detail with reference to Examples and Comparative Examples. The parts and% in the examples are shown by weight.

Abbreviations used in Examples and Comparative Examples are as follows. PB: polybutadiene SBR: styrene-butadiene rubber AN: acrylonitrile SM: styrene nBA: n-butyl acrylate MMA: methyl methacrylate AMA: allyl methacrylate

Examples and Comparative Examples ABS resin of Table 1, AS resin of Table 2, acrylic rubbers of Tables 3 and 4 were added to Table 5 (A which constitutes the thermoplastic resin composition).
Characteristics of BS resin), Table 6 and Table 7 (composition of thermoplastic resin composition and properties of synthetic resin composite) are blended and melt-kneaded at about 240 ° C to obtain a thermoplastic resin composition. It was

The thermoplastic resin composition thus obtained was mixed with 5 parts of a titanium oxide pigment and fed to a single-screw extruder equipped with a T-die, melted at about 220 ° C. and processed into a flat plate having an average wall thickness of 1 mm. . The obtained flat plate was pre-dried, and was formed by controlling the surface temperature of the flat plate with a plug-assist type compressed air vacuum forming machine to about 160 ° C. A molded product of the plastic resin composition was obtained. This molded product was combined with the uncovered box-shaped steel molded product shown in FIG. 1, and 110 parts of tolylene diisocyanate and an adduct of methylglycoside and propylene oxide (hydroxyl equivalent 110) were enclosed in a space surrounded by both molded products. 100 copies, CFC 14
A mixture of 1 part 30 parts, water 3.5 parts, di-n-octyltin laurate 0.4 parts, and tetramethylguanidine 0.2 parts was injected and reacted at 50 ° C. for 30 minutes to obtain a synthetic resin composite. It was The dimensions of the synthetic resin composite of FIG. 1 are 175 mm width × 256 mm length × 30 mm height, and the thickness of the urethane foam is 5 mm.

Examples are shown in Experiment Nos. 1 to 15 in Tables 6 and 7, and Comparative Examples are shown in Experiment Nos. 16 to 21 in Table 7. As is apparent from Tables 6 and 7, the thermoplastic resin composition constituting the synthetic resin composite of the present invention has good industrially preferable moldability, and a molded product of the thermoplastic resin composition. The synthetic resin composite composed of is excellent in environmental stress crack resistance against Freon 141b.

The ABS resin, acrylic rubber and thermoplastic resin composition described in Examples and Comparative Examples were produced as follows. (1) Manufacturing method of ABS resin Polybutadiene latex or polybutadiene latex and styrene-butadiene rubber (styrene content 2
5%) Add a deionized water, an emulsifier, and a reducing agent containing ferrous sulfate to a stainless steel reactor containing a mixture of latex, and maintain acrylonitrile, styrene, cumene hydro in a nitrogen atmosphere while maintaining the temperature at 50 ° C. Emulsion graft polymerization was carried out by continuously applying a mixture of peroxide and n-dodecyl mercaptan for 5 hours. After the temperature was properly adjusted, the temperature was raised to 70 ° C. and the temperature was maintained for 2 hours to complete the polymerization. The characteristics of the obtained ABS resin are shown in Table 1.

(2) Acrylic rubber manufacturing method A reactor made of stainless steel was charged with ion-exchanged water, an emulsifier and potassium sulphate, and the (meth) acrylic acid shown in Table 3 was maintained while maintaining the temperature at 70 ° C. under a nitrogen atmosphere. The ester monomer mixture was continuously subjected to emulsion polymerization for 7 hours, and emulsion polymerization was completed by holding the mixture at 70 ° C. for 2 hours to obtain an acrylic rubber. The characteristics of the obtained acrylic rubber are shown in Table 3.

(3) Graft Polymerization of AN and SM onto Acrylic Rubber A stainless steel reactor charged with acrylic rubber latex of sample number c1, c3 or c4 in Table 3 is a reducing agent containing ion-exchanged water and ferrous sulfate. Was added and the temperature was maintained at 50 ° C. under a nitrogen atmosphere. Emulsion graft polymerization was carried out by continuously and appropriately applying a mixture of acrylonitrile, styrene, n-dodecyl mercaptan and cumene hydroperoxide and an aqueous emulsifier solution. After the temperature was appropriately adjusted, the temperature was raised to 70 ° C. and the temperature was maintained for 2 hours to complete the polymerization. The characteristics of the obtained graft polymer are summarized in Table 4.

(4) Method for producing thermoplastic resin composition The ABS resin latex of Table 1 and the acrylic rubber latex of Table 3 or Table 4 are mixed in a latex state, and a suspension of the antioxidant is added. Dilute sulfuric acid was poured at about 90 ° C. to deposit a latex. The obtained slurry was dehydrated and dried to obtain a polymer powder. The polymer powder thus obtained and the AS resin powder shown in Table 2 were mixed in a Henschel mixer and melt-kneaded at about 240 ° C. using a twin-screw extruder to obtain a heat having the composition shown in Tables 6 and 7. A plastic resin composition was obtained. The ABS resin constituting the thermoplastic resin composition shown in Tables 6 and 7 is a mixture of the ABS resin shown in Table 1 and the AS resin shown in Table 2, and has the composition shown in Table 5.

The synthetic resin composite thus obtained was evaluated as follows. (1) Molding Workability The appearance of the molded body of FIG. 1 was observed and the following evaluations were performed. A: The pattern on the bottom is clearly transferred, and the ridges and corners of the box are also acute. B: The pattern on the bottom is slightly unclear, and the ridges and corners of the box are slightly obtuse. C: The pattern on the bottom is extremely unclear, and the ridges and corners of the box are obtuse.

(2) Resistance to environmental stress cracking The synthetic resin composite was placed in a constant temperature bath, and a cooling / heating cycle of -30 ° C / 12 hours to 40 ° C / 12 hours was repeated 3 times.
The molded body of the thermoplastic resin composition was removed from the synthetic resin composite after the cooling / heating cycle test, and the appearance was observed. A: No change B: Whitening is partially observed C: Cracking occurs

[0037]

[Table 1]

[0038]

[Table 2]

[0039]

[Table 3]

[0040]

[Table 4]

[0041]

[Table 5]

[0042]

[Table 6]

[0043]

[Table 7]

[0044]

As described above, in the synthetic resin composite of the present invention, the molding processability of the thermoplastic resin composition is good, and the environmental resistance crack resistance of the obtained synthetic resin composite is high. Since it is excellent in heat resistance, it is suitable for applications such as heat insulating materials, vibration damping materials, and sound insulating materials.

[Brief description of drawings]

FIG. 1A is a sectional view of an ABS resin molded body.
(B) shows a top view of the synthetic resin composite. (C) shows a cross-sectional view of A-A 'of the synthetic resin composite of (b).

[Explanation of symbols]

 1: ABS resin molded body 2: Steel molded body 3: Urethane foam

Claims (3)

[Claims] 1. A composition comprising a molded body of a thermoplastic resin composition containing 100 parts by weight of a rubber-containing styrene resin having the following characteristics and 0.1 to 100 parts by weight of an acrylic rubber, and a urethane foam. Resin composite. The rubber-containing styrene resin is (a) a graft copolymer [G] 5 to 50.
% Of the matrix resin [M], and (b) the graft copolymer [G] contains a conjugated diene rubber [B] containing an unsaturated nitrile monomer and an aromatic vinyl monomer. Graft branch [GM] composed of a copolymer of two or more monomers is a copolymer obtained by graft copolymerization, and the graft branch [GM] is 20 to 35% by weight of an unsaturated nitrile monomer.
And an aromatic vinyl monomer in an amount of 65 to 80% by weight, and (c) the matrix resin [M] is an unsaturated nitrile monomer in an amount of 35 to 50% by weight. It is a copolymer of two or more monomers containing 50 to 65% by weight of an aromatic vinyl monomer, and (d) the conjugated diene rubber [B] component in the rubber-containing styrene resin has 2 to 2 parts. 40 wt%, unsaturated nitrile component 20-50 wt% and aromatic vinyl component 10-78 wt%. 2. The synthetic resin composite according to claim 1, wherein the rubber-containing styrene resin is an ABS resin. 3. The glass transition temperature of acrylic rubber is 20 ° C.
The synthetic resin composite according to claim 1, wherein: