JPH11286569A - Resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a resin composition extremely improved in whether resistance without spoiling an appearance of its foamed product or its feeling e.g. feel of touch by adding a polymer comprising a specific ultraviolet ray- absorbable monomer and a specific unsaturated monomer as a polymerizable component to a foaming plastic base material. SOLUTION: This composition is obtained by including a polymer obtained by radical-polymerizing a monomer composition comprising an ultraviolet ray- absorbable monomer selected from those of formulas I and II (R<1> is H or a 1-8C hydrocarbon; R<2> and R<4> are each a lower alkylene; R<3> and R<5> are each H or methyl; and X is e.g. H or cyano) and an unsaturated monomer of formula III (R<6> is H or methyl; and Z is a >=4C hydrocarbon) in a foaming plastic base material. Monomers of formulas I and III are pref. exemplified by 2-[2'- hydroxy-5'-(methacryloyloxymethyl)phenyl]-2H-benzotriazole and cyclohexyl(meth)acrylate, respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition which improves the weather resistance while maintaining the appearance and feel when foamed and formed. More specifically,
By adding to the foamed plastic substrate a polymer containing a UV-absorbing monomer having a specific structure and an unsaturated monomer as a repeating unit, the appearance and texture of the molded article after foaming The present invention relates to a resin composition that improves weather resistance while maintaining the following.

[0002]

2. Description of the Related Art For the purpose of improving the weather resistance of, for example, a thermoplastic resin-based coating film, it has been common practice to add a low molecular weight ultraviolet absorber to a resin composition.
There has been a problem that the low molecular weight ultraviolet absorber bleeds out of the resin composition and the intended purpose cannot be sufficiently exhibited. Therefore, in order to prevent bleed-out, a means having a polymerizable double bond is used as an ultraviolet absorber, and these are homopolymerized or copolymerized to polymerize the ultraviolet absorber to suppress bleed-out. Had been. For example, JP-A-7-90184 discloses a light-resistant resin composition containing a UV-absorbing polymer having a weight-average molecular weight of 1,000 to 45,000 and a synthetic resin. JP-A-7-10954 discloses an ultraviolet-absorbing resin composition. Polyurethane having a specific structure having a functional group in a side chain, JP-A-6-25646
No. 2 discloses a polyurethane containing a hindered amine compound in a molecule.

[0003]

Indeed, by adding a polymer containing a UV-absorbing monomer or a UV-stable monomer as a repeating unit to a thermoplastic resin composition, a UV absorber or a UV-absorbing monomer can be obtained. Problems such as bleed-out of stabilizers can be solved to some extent. However, in the case of a foamed plastic substrate which is foam-molded, there is a concern that such a polymer may hinder the appearance and feel of the molded article after molding.

As a technique for improving the weather resistance of a foam molded article, for example, Japanese Patent Publication No. 2-10178 discloses a method for producing a polyurethane foam molded article using a halogenated hydrocarbon as a foaming agent. It has been proposed to improve the weather resistance by the addition of a metal. However, since these compounds are generally low molecular compounds, there are problems such as volatilization during processing and bleeding out of molded articles.

[0005]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above problems, and as a result, have found that an ultraviolet absorbing monomer having a specific structure and a specific unsaturated monomer have a specific structure in a foamed plastic substrate. If a polymer using as a monomer component is added, it is found that the weather resistance is significantly improved without impairing the appearance and feel of the molded article after foam molding, and furthermore, the present invention It was completed. That is, the resin composition of the present invention contains at least one of the UV-absorbing monomers represented by the following general formulas (1) and (2) and a resin represented by the following formula (3) in a foamed plastic substrate. It is characterized by containing a polymer obtained by radical polymerization of a monomer composition containing a saturated monomer.

[0006]

Embedded image

(Wherein, R ¹ is a hydrogen atom or a group having 1 to 1 carbon atoms)
8 represents a hydrocarbon group, R ² represents a lower alkylene group, R ³ represents a hydrogen atom or a methyl group, X represents a hydrogen atom, a halogen, a hydrocarbon group having 1 to 8 carbon atoms, a lower alkoxy group, a cyano group, Represents a group or a nitro group. )

[0008]

Embedded image

Wherein R ⁴ represents a lower alkylene group;
R ⁵ represents a hydrogen atom or a methyl group. )

[0010]

Embedded image

(In the formula, R ⁶ represents a hydrogen atom or a methyl group, and Z represents a hydrocarbon group having 4 or more carbon atoms.)

Hereinafter, the contents of the present invention will be described in detail. The resin composition of the present invention comprises a monomer composition containing an ultraviolet absorbing monomer represented by the general formulas (1) and (2) and a monomer represented by the general formula (3). Since it contains a polymer obtained by radical polymerization, it has a remarkable effect in terms of weather resistance. Although the mechanism of action has not been fully elucidated so far, by adding the polymer to a foamed plastic substrate, excellent weather resistance can be imparted without impairing the appearance and feel of the foamed molded article. Of course, the polymer using the ultraviolet absorbing monomer as one component of the monomer is obtained by incorporating the ultraviolet absorbing agent as a polymer, so that the ultraviolet absorbing agent does not bleed out.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Foamed plastic substrates used in the present invention include polyurethane, styrene resin, vinyl chloride resin, polyethylene, cellulose acetate, polyvinyl alcohol, phenolic resin, urea resin, epoxy resin, silicon resin, and polypropylene. , Polyester, acrylic resin, urea resin, polyamide, ethylene-vinyl acetate copolymer, butadiene-acrylonitrile copolymer,
The term "butadiene-acrylonitrile-styrene copolymer" refers to a foamed plastic substrate in the present invention when foaming is carried out using a foaming agent or the like.

Examples of the blowing agent include inorganic compounds such as ammonium carbonate and sodium bicarbonate; azo compounds such as 2,2'-azoisobutyronitrile, azohexahydrobenzonitrile, azodicarboxylic amide, and diazoaminobenzene; benzenesulfohydrazide N, Sulfohydrazide compounds such as benzene-1,3-disulfohydrazide, diphenylsulfone-3,3′-disulfohydrazide;
N'-dinitrosopentamethylenetetramine, N, N '
Nitroso compounds such as -dinitroso-N, N'-dimethylterephthalamide; terephthalazide, para-ter;
Azide compounds such as t-butylbenzazide and the like can be mentioned.

In the present invention, the compound is represented by the general formula (1).
The ultraviolet absorbing monomer represented by the formula: ¹ Is a hydrogen atom or
A hydrocarbon group having 1 to 8 carbon atoms;^Two Is lower al
Composed of a kylene group;^Three Is a hydrogen atom or a methyl group
X is a hydrogen atom, a halogen, a carbon having 1 to 8 carbons.
Hydride group, lower alkoxy group, cyano group or nitro group
And benzotriazoles.

In the above formula, examples of the substituent represented by R ¹ include a hydrogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group,
t-butyl group, pentyl group, hexyl group, heptyl group,
A chain hydrocarbon group such as an octyl group; a cyclopropyl group,
A cyclopentyl group, a cyclohexyl group, a cycloheptyl group, an alicyclic hydrocarbon group such as cyclooctyl group; a phenyl group, a tolyl group, a xylyl group, a benzyl group, an aromatic hydrocarbon group such as a phenethyl group, Table by R ² The substituent is specifically an alkylene group having 1 to 6 carbon atoms, such as a linear alkylene group such as a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group and a hexylene group, and 2-methyl. A branched alkylene group such as a propylene group, a 2,2-dimethylpropylene group, a 2-methylbutylene group, a 2,2-dimethylbutylene group, a 2,3-dimethylbutylene group, and a substituent represented by X Is hydrogen;
Halogens such as fluorine, chlorine, oxine and iodine; methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl,
Chain hydrocarbon groups such as hexyl group, heptyl group and octyl group: alicyclic hydrocarbon groups such as cyclopropyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group and cyclooctyl group: phenyl group, tolyl group, xylyl group Benzyl, phenethyl and the like; aromatic hydrocarbon groups such as methoxy, ethoxy, propoxy, butoxy, butoxy, pentoxy, heptoxy and the like; lower alkoxy groups having 1 to 6 carbon atoms; cyano groups; nitro groups.

Examples of the ultraviolet absorbing monomer represented by the general formula (1) include 2- [2'-hydroxy-5 '
-(Methacryloyloxymethyl) phenyl] -2H-
Benzotriazole, 2- [2'-hydroxy-5'-
(Methacryloyloxyethyl) phenyl] -2H-benzotriazole, 2- [2'-hydroxy-5'-
(Methacryloyloxypropyl) phenyl] -2H-
Benzotriazole, 2- [2'-hydroxy-5'-
(Methacryloyloxyhexyl) phenyl] -2H-
Benzotriazole, 2- [2'-hydroxy-3'-
tert-butyl-5 ′-(methacryloyloxyethyl) phenyl] -2H-benzotriazole, 2-
[2′-hydroxy-5′-tert-butyl-3′-
(Methacryloyloxyethyl) phenyl] -2H-benzotriazole, 2- [2'-hydroxy-5'-
(Methacryloyloxyethyl) phenyl] -5-chloro-2H-benzotriazole, 2- [2′-hydroxy-5 ′-(methacryloyloxyethyl) phenyl]
-5-methoxy-2H-benzotriazole, 2-
[2′-Hydroxy-5 ′-(methacryloyloxyethyl) phenyl] -5-cyano-2H-benzotriazole, 2- [2′-hydroxy-5 ′-(methacryloyloxyethyl) phenyl] -tert-butyl-2H
-Benzotriazole, 2- [2'-hydroxy-5 '
-(Methacryloyloxyethyl) phenyl] -5-nitro-2H-benzotriazole and the like,
It is not particularly limited to these. One kind of these ultraviolet absorbing monomers represented by the general formula (1) may be used alone, or two or more kinds thereof may be appropriately mixed and used.

In the ultraviolet absorbing monomer represented by the general formula (2), a substituent represented by R ⁴ is a lower alkylene group, and a hydrogen atom represented by R ⁵ or Benzotriazoles composed of a methyl group.

In the above formula, the substituent represented by R ⁴ is specifically an alkylene group having 2 or 3 carbon atoms, such as an ethylene group, a trimethylene group and a propylene group.

The UV-absorbing monomer represented by the general formula (2) includes, for example, 2- [2'hydroxy-5 '
-(Β-methacryloyloxyethoxy) -3′-te
rt-butylphenyl] -4-tert-butyl-2H
-Benzotriazole, but is not particularly limited thereto. Only one kind of these ultraviolet absorbing monomers represented by the general formula (2) may be used, or two or more kinds may be appropriately mixed.

In the unsaturated monomer represented by the general formula (3) according to the present invention, the substituent represented by R ⁶ is a hydrogen atom or a methyl group, and the substituent represented by Z is It is an unsaturated monomer composed of a hydrocarbon group having 4 or more carbon atoms.

In the above formula, the substituent represented by Z is an alicyclic hydrocarbon group having 4 or more carbon atoms such as a cyclohexyl group, a methylcyclohexyl group, a cyclododecyl group; a butyl group, an isobutyl group, a tert-butyl group; 2-ethylhexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, pentadecyl group, octadecyl group or other linear or branched alkyl group having 4 or more carbon atoms; bornyl group, isobornyl group, Is a polycyclic hydrocarbon group having 4 or more carbon atoms.

The unsaturated monomer represented by the general formula (3) according to the present invention is preferably, for example, cyclohexyl (meth) acrylate, methylcyclohexyl (meth) acrylate, cyclododecyl (meth) acrylate, te
rt-butylcyclohexyl (meth) acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, lauryl (meth) acrylate, isobornyl (meth) acrylate, stearyl (meth)
Acrylate, 2-ethylhexyl (meth) acrylate and the like can be mentioned, and one or more of these can be used.

Further, other copolymerizable unsaturated monomers other than the above-mentioned monomers are required for a polymer using a UV-absorbing monomer and a specific unsaturated monomer as a monomer component. Any material that does not impair various physical properties can be used. Specifically, (meth) acrylic acid, crotonic acid, itaconic acid,
Carboxyl group-containing unsaturated monomers such as maleic acid and maleic anhydride; 2- (meth) acryloyloxyethyl acid phosphate, 2- (meth) acryloyloxypropyl acid phosphate, 2- (meth) acryloyloxy-3-chloro Acidic phosphate unsaturated monomers such as propyl acid phosphate and 2-methacryloyloxyethylphenylphosphoric acid; hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, caprolactone-modified hydroxy (meth) acrylate (for example, Daicel Manufactured by Chemical Industry Co., Ltd .; trade name "Placcel FM"; hydroxyl-containing monomers such as mono (meth) acrylate of polyester diol obtained from phthalic acid and propylene glycol; methyl (meth) acrylate , Ethyl (meth) acrylate,
Propyl (meth) acrylate, isopropyl (meth)
(Meth) acrylic acid lower alkyl esters such as acrylates; epoxy group-containing unsaturated monomers such as glycidyl (meth) acrylate; (meth) acrylamide;
N, N'-dimethylaminotyl (meth) acrylate;
Nitrogen-containing unsaturated monomers such as vinylpyridine and vinylimidazole; halogen-containing unsaturated monomers such as vinyl chloride and vinylidene chloride; aromatic unsaturated monomers such as styrene, α-methylstyrene and vinyltoluene; acetic acid Vinyl esters such as vinyl; vinyl ether; and the like, but are not particularly limited thereto. As the other monomer, only one kind may be used as needed, or two or more kinds may be used.

The amounts of the various monomers used are not particularly limited, but the total amount of the UV-absorbing monomers represented by the general formulas (1) and (2) depends on the amount of the resin composition. It is desired that the content be 0.1 to 20% by weight based on the solid content. Describing a more preferable range, the lower limit is preferably 0.5 wt%, more preferably 1 wt%. On the other hand, the upper limit is preferably 15% by weight, more preferably 10% by weight. If the total amount of the UV-absorbing monomer is less than 0.1 wt%, the weather resistance of the foamed product becomes insufficient, and if it is more than 20 wt%, the appearance and feel of the foamed molded product are felt. May be hindered. Moreover, 0.5 to 90 wt% with respect to the monomer composition.
It is desired that Describing a more preferable range, the lower limit is preferably 3 wt%, more preferably 5 wt%. On the other hand, the upper limit is preferably 85
wt%, more preferably 80 wt%. If the total content of the UV-absorbing monomer is less than 0.5 wt%, the weather resistance of the foam molded article becomes insufficient, and 90 wt%.
If the amount is larger than the above range, unreacted monomers may be generated and the unreacted monomers may be eluted.

The amount of the unsaturated monomer represented by the general formula (3) is 0.5 to 50 wt% based on the solid content of the resin composition.
% Is desired. Describing a more preferable range, the lower limit is preferably 1 wt%, more preferably 3 wt%. On the other hand, the upper limit is preferably 4
0 wt%, more preferably 30 wt%. It is desired that the content be 5 to 99% by weight based on the monomer composition. To describe a more preferable range, the lower limit is preferably 10 wt%, more preferably 15 wt%.
It is. On the other hand, the upper limit is preferably 95% by weight, more preferably 90% by weight. If the amount is less than 5 wt%, the appearance and feel of the molded product after foaming will be insufficient, and if it is more than 99 wt%, the weather resistance of the foamed product may be insufficient. is there.

The method of mixing the monomers is not particularly limited, and a conventionally known mixing method can be employed.

The polymerization method for copolymerizing the monomer composition is not particularly limited, and a conventionally known polymerization method can be employed. For example, polymerization methods such as solution polymerization, dispersion polymerization, suspension polymerization, and emulsion polymerization can be used. Solvents that can be used when polymerizing the monomer composition using the solution polymerization method include toluene, xylene, and other high-boiling aromatic solvents; butyl acetate, ethyl acetate, and ester solvents such as cellosolve acetate. Ketone solvents such as acetone, methyl ethyl ketone and methyl isobutyl ketone; and dimethylformamide. Of course, the solvents that can be used are not limited to these solvents. These solvents may be used alone or in combination of two or more. The amount of the solvent used may be appropriately determined in consideration of the concentration of the product and the like.

When copolymerizing the monomer composition, a polymerization initiator is used. As the polymerization initiator, for example, 2,
2'-azobis- (2-methylbutyronitrile), te
rt-butylperoxy-2-ethylhexanoate,
Examples include ordinary radical polymerization initiators such as 2,2'-azobisisobutyronitrile, benzoyl peroxide, and di-tert-butyl peroxide. The amount of the polymerization initiator to be used should be appropriately determined from the required characteristic values of the polymer and the like, and is not particularly limited.

The reaction temperature is not particularly limited, but is preferably in the range of room temperature to 200 ° C, and is preferably 40 to 140 ° C.
Is more preferred. The reaction time may be appropriately set according to the composition of the monomer composition to be used, the type of the polymerization initiator, and the like so that the polymerization reaction is completed.

The produced polymer may be mixed with the foamed plastic substrate in a solution state, or may be mixed with the foamed plastic substrate as a dried powder.
It is desirable to mix before foaming.

The addition of the polymer to the foamed plastic substrate is 0.1 to 50 wt.% Based on the solid content of the resin composition.
%. Describing a more preferable range, the lower limit is preferably 1 wt%, more preferably 3 wt%. On the other hand, the upper limit is preferably 45 wt%, more preferably 30 wt%.
If the amount is less than 0.1 wt%, the weather resistance of the foam molded article becomes insufficient, and if it is more than 50 wt%, the texture and mechanical properties of the foam molded article may be reduced.

In order to control the decomposition temperature of the foaming agent,
Foaming accelerators such as inorganic salts, metallic soaps, organic and inorganic acids, organic acids, halogenated organic acids, anhydrides of organic acids, polyhydric alcohols, nitrogen compounds, sulfur compounds, phosphates, tin compounds, etc. If necessary, an agent can be added to the foamed plastic substrate.

As a method for foaming the resin composition, a gas mixing method, a foaming agent decomposition method, a solvent diffusion method, a chemical reaction method and the like can be applied.

As foam molding, any molding such as block molding, plate molding, and die molding is possible, and ordinary injection, extrusion, compression, vacuum molding and the like can be applied to these.

As the foamed plastic using the resin composition of the present invention, conventional foamed plastics such as synthetic leather, automobile interior sheets, agricultural sheets, cushioning materials, heat insulating materials, sound absorbing materials, lightweight materials, and packaging materials are used. It can be suitably used for all kinds of applications. Particularly, since the weather resistance is remarkably improved, it can be suitably used for a material used outdoors.

The resin composition of the present invention may contain various additives when used. As an additive, for example, a leveling agent generally used in a film forming composition such as a paint; graphite, molybdate orange, navy blue, cadmium-based pigment, titanium white, composite oxide pigment, transparent iron oxide, carbon black Pigments such as cyclic high-grade pigments, soluble azo pigments, copper phthalocyanine pigments, dyed pigments, pigment intermediates; pigment dispersants; antioxidants; viscosity modifiers; metal deactivators; Filler; reinforcing agent; plasticizer; lubricant; anticorrosive;
Rust inhibitors; fluorescent brighteners; organic and inorganic flame retardants; anti-dripping agents; melt flow modifiers;

[0038]

The present invention will be described in more detail with reference to the following Examples and Comparative Examples, but the present invention is not limited thereto. Unless otherwise specified, "parts" described in Examples and Comparative Examples are parts by weight and "%"
Represents "% by weight".

(Synthesis of Resin Composition) Synthesis Example 1 30 parts of dimethylformamide, 2- [2'-hydroxy] was placed in a 0.5-liter flask equipped with a stirrer, a dropping port, a thermometer, a cooling pipe, and a nitrogen gas inlet. -5 '-(methacryloyloxyethyl) phenyl] -2H-benzotriazole (40 parts) and 10 parts of 2- [2'-hydroxy-5'-(methacryloyloxyethyl) phenyl] -2H-benzotriazole in the dropping tank. , 50 parts of cyclohexyl methacrylate, and 8 parts of tert-butylperoxy-2-ethylhexanoate as an initiator. First, 40 wt% of the mixture in the dropping tank was added to the flask, and nitrogen gas was introduced.
Heated to 20 ° C. After the temperature rise, the remaining mixture in the dropping tank is dropped over 2 hours. After the dropwise addition, the mixture was further heated for 2 hours to obtain a 50% solution of an acrylic resin. The number average molecular weight of this acrylic resin was 2,900. This acrylic resin is referred to as polymer 1.

Synthesis Examples 2 to 10 At the compounding ratios shown in Tables 1 and 2, the desired polymers 2 to 10 were obtained in the same manner as in Synthesis Example 1.

[0041]

[Table 1]

[0042]

[Table 2]

UVA1: 2- [2'-hydroxy-5 '
-(Methacryloyloxyethyl) phenyl] -2H-
Benzotriazole UVA2: 2- [2′-hydroxy-5 ′-(β-methacryloyloxyethoxy) -3′-tert-butylphenyl] -4-tert-butyl-2H-benzotriazole CHMA: cyclohexyl methacrylate i-BMA: Isobutyl methacrylate 2EHA: 2-ethylhexyl acrylate t-BMA: tert-butyl methacrylate LMA: lauryl methacrylate St: styrene DMF: dimethylformamide Initiator 1: tert-butylperoxy-2-ethylhexanoate Initiator 2: 2,2 '-Azobis (2-methylbutyronitrile)

Example 1 Polymer 1 was added to 100 parts of a solution containing 30% by weight of polyurethane (“Hilac 1061” manufactured by Toyo Polymer Co., Ltd.) as a foamed plastic substrate in dimethylformamide as a solvent. 8 parts of a solution containing 50 wt% and 40 parts of dimethylformamide are added, and the mixture is stirred with a rotary stirrer at 500 rpm × 30 minutes. After defoaming, apply to glass plate. Then put in warm water of 50 ° C for 6h
d. At this time, the solvent is non-solvent (in this case, water)
, The polymer composition gels. The gel is removed from the glass plate and washed with a large amount of water. Thereafter, drying is performed at 90 ° C. for 30 minutes to obtain a porous polymer body having a thickness of 5 mm.

The texture of the obtained porous polymer was visually evaluated as follows. The test was conducted for 120 hours with a sunshine weather meter as an accelerated weather resistance tester.
The degree of yellowing (referred to as “Δb”) was measured. Table 3 shows the results.

Examples 2 to 15 Polymer porous bodies were obtained in the same manner as in Example 1 using the various materials and the amounts shown in Tables 3 and 4, and the texture and yellowing degree were determined in the same manner as in the Examples. Was measured. The results are shown in Tables 3 and 4.

COMPARATIVE EXAMPLE 1 40 parts of dimethylformamide was added to 100 parts of a solution containing 30 wt% of polyurethane (“Hilac 1061” manufactured by Toyo Polymer Co., Ltd.) as a foamed plastic substrate in dimethylformamide as a solvent. And 1 part of a high molecular weight ultraviolet absorber (“ADK STAB LA-31” manufactured by Asahi Denka Kogyo Co., Ltd.), and the mixture was stirred at 500 r with a rotary stirrer.
Stir at pm × 30 min. After defoaming, apply to glass plate. Next, it is immersed in 50 ° C. warm water for 6 hours. At this time, since the solvent is replaced with a non-solvent (in this case, water), the polymer composition gels. The gel is removed from the glass plate and washed with a large amount of water. After that, 90 ° C x 30m
Drying is carried out in order to obtain a polymer porous body having a thickness of 5 mm.

The texture of the obtained porous polymer body was visually evaluated as follows. The test was conducted for 120 hours with a sunshine weather meter as an accelerated weather resistance tester.
The degree of yellowing (referred to as “Δb”) was measured. Table 5 shows the results.

Comparative Examples 2 to 4 Using the various materials and amounts shown in Table 5, a polymer porous body was obtained in the same manner as in Comparative Example 1, and the hand and yellowing degree were measured in the same manner as in Comparative Example. . Table 5 shows the results.

[0050]

[Table 3]

[0051]

[Table 4]

Polyurethane resin: "Hilac 1061" manufactured by Toyo Polymer Co., Ltd. (solid content: 30 wt%) Acrylic resin: "Sebian-M" manufactured by Daicel Chemical Industries, Ltd. Cellulose acetate: "Daicel Cotton L-AC" manufactured by Daicel Chemical Industries, Ltd. (Solid content 25wt%)

[0053]

[Table 5]

Polyurethane resin: “Hi-Rack 1061” manufactured by Toyo Polymer Co., Ltd. (solid content: 30 wt%) Acrylic resin: “Sebian-M” manufactured by Daicel Chemical Industries, Ltd. Polymer ultraviolet absorber 1: “Adekastab LA-” manufactured by Asahi Denka Kogyo KK 31 "(number average molecular weight: 659) Polymer UV stabilizer 1:" ADEKA STAB LA-52 "manufactured by Asahi Denka Kogyo Co., Ltd. (number average molecular weight: 847) Polymer UV absorber 2:" PUVA-30 "manufactured by Otsuka Chemical Co., Ltd.
M "(number average molecular weight: about 10,000)

As is apparent from Tables 3 to 5, the foamed plastic base material contains a polymer using a UV-absorbing monomer having a specific structure and a specific unsaturated monomer as monomer components. When the resin composition of the present invention is used, the texture after the foaming treatment is not impaired at all, and the yellowing degree is 4 in each of the examples even after 120 hours of the accelerated weathering test. And less than that of Comparative Examples 1 to 3, indicating much better weather resistance. On the other hand, Comparative Example 4 has a good yellowing degree of 5.5, which is a good result. It is considered that this is because the number average molecular weight of the added polymeric ultraviolet absorber 2 was about 10,000, and it was difficult for the absorbent to elute from the foamed molded article during the foaming process. However, the texture after foaming is impaired due to poor compatibility between the ultraviolet absorber and the foamed plastic substrate.

[0056]

According to the present invention, a polymer obtained by radical polymerization of a monomer composition containing an ultraviolet absorbing monomer having a specific structure and a specific unsaturated monomer in a foamed plastic substrate is added. According to the resin composition, the weather resistance is remarkably improved without impairing the appearance and feel of the molded article after foam molding.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08F 220: 36) (C08L 101/00 33:06)

Claims (1)

[Claims] 1. A foamed plastic substrate comprising at least one of an ultraviolet absorbing monomer represented by the following general formulas (1) and (2) and an unsaturated monomer represented by the following general formula (3): A resin composition comprising a polymer obtained by radical polymerization of a monomer composition containing a polymer. Embedded image (Wherein, R ¹ represents a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, R ² represents a lower alkylene group, R ³ represents a hydrogen atom or a methyl group, X represents a hydrogen atom, a halogen,
Represents a hydrocarbon group having 1 to 8 carbon atoms, a lower alkoxy group, a cyano group or a nitro group. ) (In the formula, R ⁴ represents a lower alkylene group, and R ⁵ represents a hydrogen atom or a methyl group.) (In the formula, R ⁶ represents a hydrogen atom or a methyl group, and Z represents a hydrocarbon group having 4 or more carbon atoms.)