JP2002128936A - Acrylic sol composition and foam obtained using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an acrylic sol composition for an acrylic foam exhibiting excellent sol characteristics such as low viscosity and coatability and easily formable with heat, and an acrylic foam prepared using the composition. SOLUTION: The acrylic sol composition comprises (A) 100 pts.wt. of an acrylic resin component, (B) 10-200 pts.wt. of a plastic component which comprises an acrylic low-molecular-weight polymer mainly composed of an acrylic monomer, has a weight-average molecular weight of 500-2,000 and is liquid at ordinary temperature, (C) 1.0-20 pts.wt. of a heating type foaming agent, and occasionally (D) a crosslinking agent. The foam is obtained by heating the acrylic sol composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an acrylic sol composition, and more particularly, to an acrylic resin in which an acrylic low molecular weight polymer as a plasticizer and a heating type foaming agent are dispersed. The present invention relates to an acrylic sol composition excellent in moldability and an acrylic foam using the same, which is excellent in weather resistance and safety.

[0002]

2. Description of the Related Art A plastisol is a flowable paste-like sol obtained by dispersing a fine powder of a thermoplastic resin in a plasticizer. When heated, the resin powder and the plasticizer fuse to form a homogeneous synthetic resin. Therefore, it is widely used in the fields of wall covering materials, flooring materials, dolls, toys, automobile undercoating, and PVC coated steel sheets. In such a field, a plastisol to which a foaming agent is added for the purpose of reducing the weight and imparting elasticity is known. These plastisols include:
What disperse | distributed the vinyl chloride resin fine powder in the phthalic-acid type compound which is a plasticizer is mainly used.

However, in recent years, phthalic acid compounds used as plasticizers have been increasingly suspected as endocrine disrupting substances, and a plasticizer that is friendly to the human body and the environment has been demanded. In addition, it is known that dioxin is generated when vinyl chloride-based plastisol molded products are incinerated with other plastics and the like.To reduce the amount of dioxin generated, it is effective to reduce the amount of vinyl chloride-based resin. Have been.

For this reason, attempts have been made to obtain a plastisol using a plasticizer other than a phthalic acid-based compound or to obtain an acrylic sol using an acrylic resin instead of a vinyl chloride resin. For example, an acrylic sol excellent in dispersibility and compatibility with a plasticizer, storage stability, fluidity, and the like has not been obtained.

For example, an acrylic sol using a polyester-based plasticizer has been reported. However, the compatibility of the acrylic resin and the polyester-based plasticizer is poor due to the polarity, which causes problems such as exudation after molding. There is a problem that it cannot be used for components requiring high durability such as automobile parts.

Acrylic sols containing a foaming agent are disclosed in JP-A-8-60600 and JP-A-11-357.
No. 84 describes a foamable acrylic sol using special acrylic fine particles, but uses a phthalic acid ester as a plasticizer, which may affect humans and the environment.

[0007]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide excellent sol physical properties such as excellent dispersibility and compatibility with a plasticizer, storage stability, low viscosity and coating properties, An object of the present invention is to provide an acrylic sol composition from which an excellent foam can be obtained and a foam using the same.

[0008]

Means for Solving the Problems The present inventors have conducted various studies on plasticizers for acrylic sol and found that an acrylic low molecular weight polymer having a specific molecular weight range can disperse an acrylic resin with good compatibility. It was found that the above problem could be solved by adding a heating type foaming agent, and the present invention was completed. Further, it has been found that a foam excellent in stability over time and weather resistance can be obtained by blending a crosslinking agent.

That is, the present invention provides the following component (A):
(B) and (C) (A) 100 parts by weight of an acrylic resin component (B) Acrylic low molecular weight polymer having a weight average molecular weight of 500 to 2,000 and a liquid at room temperature and containing an acrylic monomer as a main component. The present invention provides an acrylic sol composition containing 10 to 200 parts by weight of a plastic component (C) 1.0 to 20 parts by weight of a heating type foaming agent.
Further, the present invention provides a molded product prepared by heating the acrylic sol composition.

Further, the present invention provides the following component (A):
(B), (C) and (D) (A) 100 parts by weight of acrylic resin component (B) Acrylic resin which is liquid at normal temperature and has a weight-average molecular weight of 500 to 2,000 containing acrylic monomer as a main component. Plastic component which is a molecular polymer 10 to 200 parts by weight (C) Heating type foaming agent 1.0 to 20 parts by weight (D) (A) Functional group of acrylic resin component and / or (B) acrylic monomer The present invention provides an acrylic sol composition containing a crosslinking agent having two or more reactive functional groups in a molecule.
Further, the present invention provides a molded product prepared by heating the acrylic sol composition.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The acrylic sol composition of the present invention comprises
An acrylic resin component (A), a plastic component (B), and
It is prepared by dispersing in a heating type foaming agent (C).

As the acrylic resin of the acrylic resin component (A), methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate,
i-butyl (meth) acrylate, t-butyl (meth)
Acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl (meth)
Acrylate, nonyl (meth) acrylate, dodecyl (meth) acrylate, stearyl (meth) acrylate and other homopolymers or copolymers containing alkyl acrylate as a main component, in some cases,
Monomers such as phenyl (meth) acrylate, benzyl (meth) acrylate, styrene, methyl styrene, vinyl chloride, and vinyl acetate may be copolymerized. Functional group-containing monomers such as carboxyl group-containing monomers, hydroxyl group-containing monomers such as 2-hydroxyethyl (meth) acrylate, and epoxy group-containing monomers such as glycidyl (meth) acrylate, and dimethylaminomethyl methacrylate A functional group-containing monomer such as an amino group-containing monomer may be copolymerized. However, it is not preferable to form a crosslinked polymer by copolymerizing a crosslinkable monomer such as ethylene glycol di (meth) acrylate and divinylbenzene.

When the crosslinking agent (D) is blended,
The acrylic resin component (A) is preferably a copolymer having the functional group in the molecule.

As the acrylic resin of the acrylic resin component (A), a resin obtained by a known polymerization method or a resin obtained by granulating the resin by a method such as pulverization can be used. Those obtained by a free emulsion polymerization method are preferable, and the shape is 0.1 μm in particle size.
It is preferably in the form of powder having a size of not less than 20 μm and not more than 20 μm. When the particle size is less than 0.1 μm, the viscosity becomes extremely high when the acrylic sol composition is used, and the moldability is poor. When the particle size exceeds 20 μm, the strength of the molded product is not sufficient.

The acrylic resin of the acrylic resin component (A) has a weight average molecular weight of 100,000 to 1 by GPC.
Preferably, it is about one million. Weight average molecular weight is 1
If it is less than 100,000, the storage stability as an acrylic sol tends to deteriorate, and if it exceeds 1,000,000, the strength of the molded product tends to decrease.

As a more preferred acrylic resin, a polymer mainly containing an alkyl methacrylate having an alkyl group having 1 to 4 carbon atoms is preferable. In particular, an alkyl methacrylate having an alkyl group having 1 to 4 carbon atoms is preferable. Ester 1
0.1 to 10 parts by weight of the functional group-containing monomer.
A polymer obtained by copolymerizing parts by weight is preferable.

The plastic component (B) of the present invention is a low molecular weight polymer mainly composed of an acrylic monomer having a weight average molecular weight in the range of 500 to 2,000 by GPC, and is a liquid at room temperature. is there. When the weight average molecular weight is less than 500,
Poor storage stability and easy to bleed during molding. Also,
When the weight average molecular weight exceeds 2,000, it is difficult to mix uniformly with the acrylic resin component (A).

Such a low-molecular-weight polymer is obtained by converting a monomer used for the acrylic resin of the acrylic resin component (A) into a substance that acts as a chain transfer agent, for example, methyl mercaptan, ethyl mercaptan, butyl mercaptan, Dodecyl mercaptan, mercaptopropionic acid,
It can be obtained by polymerizing with a thermal polymerization initiator or a UV polymerization initiator in the presence of methyl thioglycolate, thioglycerol, 2-mercaptoethanol, n-dodecylmercaptan, thioglycolic acid and the like.

Further, the low molecular weight polymer is obtained by subjecting the monomer used for the acrylic resin of the acrylic resin component (A) to thermal polymerization under high temperature and pressure in the presence or absence of a chain transfer agent. Can also be obtained.

Among these low molecular weight polymers, preferred is an acrylic low molecular weight polymer comprising a copolymer of a (meth) acrylic acid alkyl ester having an alkyl group having 1 to 2 carbon atoms and a functional group-containing monomer. Polymers may be mentioned. Particularly, it is preferably obtained by copolymerizing 5 to 100 parts by weight of a functional group-containing monomer with respect to 100 parts by weight of methyl (meth) acrylate and / or ethyl (meth) acrylate.

The plastic component (B) of the present invention is blended in an amount of 10 to 200 parts by weight based on 100 parts by weight of the acrylic resin component (A). More preferably, 50 to 120 parts by weight is blended. When the blending amount of the plastic component (B) is less than 10 parts by weight, it is impossible to uniformly mix the resin component (A) and the viscosity of the sol composition is remarkably increased, so that it becomes easy to apply the sol composition. If it exceeds, the surface of the molded product becomes sticky, resulting in a product defect.

The heating type foaming agent of the present invention generates bubbles by heating at about 80 ° C. or more, and a microcapsule type foaming agent and a heat decomposition type foaming agent can be used. Examples of the microcapsule-type foaming agent include microballoons manufactured by Matsumoto Yushi Pharmaceutical Co., Ltd., Expancel manufactured by Expancel, Saran microsphere manufactured by Dow Chemical, and the like.

Examples of the heat-decomposable blowing agent include azo-based heat-decomposable foaming agents such as azodicarbonamide, azobisisobutyronitrile, azobishexahydrobenzonitrile, and azobisformamide, and N, N'-dinitrosopenta. Nitroso-based pyrolytic foaming agents such as methylenetetramine, N, N'-dinitroso-N, N'-dimethylterephthalamide, P-toluenesulfonylhydrazide, P, P'-oxybisbenzenesulfonylhydrazide, benzenesulfonylhydrazide, etc. Hydrazine-based thermal decomposition type foaming agents and the like can be mentioned. In the present invention, a foaming aid may be added as necessary.

The heating type foaming agent (C) is added in an amount of 1.0 to 20 parts by weight based on 100 parts by weight of the acrylic resin component (A). More preferably, it is added in an amount of 2.0 to 15 parts by weight. If the amount of the heating type foaming agent (C) is less than 1.0 part by weight, a sufficient foaming state cannot be exhibited, and if it exceeds 20 parts by weight, the surface smoothness of the foam deteriorates due to outgassing, Product defects.

The acrylic sol composition of the present invention may contain a crosslinking agent (D) as a fourth component. The cross-linking agent (D) is a compound having two or more organic groups in the molecule having reactivity with the functional group of the acrylic resin component (A) and / or the functional group of the plastic component (B). And isocyanate compounds having two or more isocyanate groups therein, and epoxy compounds having two or more epoxy groups in the molecule. Specific examples of the isocyanate compound used as the crosslinking agent (D) include tolylene diisocyanate (TDI), tolylene diisocyanate, lysine triisocyanate, chlorophenylene diisocyanate,
Isocyanate monomers such as diisocyanyl diphenylmethane, hexamethylene diisocyanate, tetramethylene diisocyanate, isophorone diisocyanate, hydrogenated diphenylmethane diisocyanate, and isocyanate compounds or isocyanurates obtained by adding these isocyanate monomers with trimethylolpropane, etc. Examples thereof include urethane prepolymer-type isocyanates which have been subjected to an addition reaction such as a type compound, a known polyether polyol, polyester polyol, acrylic polyol, polybutadiene polyol, and polyisoprene polyol.

Specific examples of the epoxy compound used as the crosslinking agent (D) include N, N-diglycidylaniline, N, N-diglycidyltoluidine, mN, N-diglycidylaminophenylglycidyl ether. , Triglycidyl isocyanurate, N, N, N ', N'-tetraglycidylaminophenylmethane, N, N, N', N'-tetraglycidyl-m-xylenediamine, 1,3-bis (N, N- Diglycidylaminomethyl) cyclohexane and the like.

The amount of the crosslinking agent (D) is from 0.001 to 1.0 based on 100 parts by weight of the acrylic resin component (A).
Parts by weight are preferred, and particularly 0.01 to 0.5 part by weight when the crosslinking agent (D) is an isocyanate compound,
In the case of an epoxy compound, the amount is preferably 0.002 to 0.2 parts by weight.

The acrylic sol composition of the present invention contains an acrylic resin component (A), a plastic component (B) and a heating type foaming agent (C). In at least one of the acrylic resin component (A) and the plastic component (B) has a functional group reactive with a crosslinking agent.

In the production of the acrylic sol composition of the present invention, 100 parts by weight of the acrylic resin component (A) and 1.0 to 20 parts by weight of the heating type foaming agent (C) are added to the plastic component (B) according to a conventional method. To 10 to 200 parts by weight. When the crosslinking agent (D) is blended, the acrylic resin component (A), the heating type foaming agent (C) and the crosslinking agent (D) may be dispersed in the plastic component (B).

The acrylic sol composition thus obtained is
An acrylic foam can be obtained according to a conventionally known foaming sol molding method. For example, in order to obtain a sheet-like foam, an acrylic sol composition is applied on a polyester film having an appropriate thickness, for example, at a thickness of about 0.5 mm, and then at a temperature of about 120 ° C. for about 5 minutes. After heating and melting, heating may be performed at a temperature equal to or higher than the decomposition temperature of the heating type foaming agent for about 10 minutes.

In the present invention, for the purpose of adjusting the fluidity and coatability of the acrylic sol composition, and adjusting the flexibility of the obtained sol molded product, other than the plastic component (B) of the present invention. Conventionally known plasticizers may be used in combination. Further, the acrylic sol composition of the present invention may contain an appropriate amount of an antioxidant, a pigment, a filler, a flame retardant, an ultraviolet absorber, and the like, if necessary.

The acrylic sol composition of the present invention obtained as described above has good dispersibility and compatibility, and excellent sol physical properties such as storage stability, fluidity and coating properties. Moreover, an excellent foam can be easily obtained by heating.

Therefore, the acrylic sol composition of the present invention can be replaced with a conventional acrylic sol by replacing a wall covering material, a flooring material, a leather, a vibration damping material, an industrial part, an electric insulating part, a toy / miscellaneous goods, an automobile interior material, a sealing material. And the like.

[0034]

Next, the present invention will be described in more detail with reference to Production Examples, Comparative Production Examples, Examples, Comparative Examples and Test Examples.
The present invention is not limited to these.

Production Example 1 Synthesis of Acrylic Low-Molecular-Weight Polymer (Plastic Component): A 1-liter four-necked flask equipped with a thermometer, a nitrogen inlet tube and a reflux condenser was charged with 60 parts by weight of ethyl methacrylate as a monomer. Parts, 15 parts by weight of methyl thioglycolate, dimethyl
One part by weight of 2,2′-azobis (2-methylpropionate) was added, and the mixture was reacted at 85 ° C. for 5 hours under a nitrogen atmosphere. As a result, an acrylic low molecular weight polymer having a weight average molecular weight by GPC of 1,900 was obtained.

Production Example 2 Synthesis of acrylic low molecular weight polymer (plastic component): 95 parts by weight of monomer ethyl acrylate was placed in a 1-liter four-necked flask equipped with a thermometer, a nitrogen inlet tube and a reflux condenser. And 5 parts by weight of acrylic acid, 15 parts by weight of 3-mercapto-1,2-propanediol and 1 part by weight of dimethyl 2,2'-azobis (2-methylpropionate) were added under nitrogen atmosphere.
The reaction was performed at 0 ° C. for 5 hours. As a result, an acrylic low molecular weight polymer having a weight average molecular weight by GPC of 1,200 was obtained.

Production Example 3 Synthesis of Acrylic Low Molecular Weight Polymer (Plastic Component): A 1-liter four-necked flask equipped with a thermometer, a nitrogen inlet tube and a reflux condenser was charged with 60 parts by weight of methyl methacrylate as a monomer. Parts, 30 parts by weight of n-dodecyl mercaptan and dimethyl
One part by weight of 2,2′-azobis (2-methylpropionate) was added, and the mixture was reacted at 85 ° C. for 5 hours under a nitrogen atmosphere. As a result, an acrylic low molecular weight polymer having a weight average molecular weight of 600 by GPC was obtained.

Comparative Production Example 1 Synthesis of acrylic low molecular weight polymer: 100 parts by weight of monomer 2-ethylhexyl acrylate was placed in a 1-liter four-necked flask equipped with a thermometer, a nitrogen inlet tube and a reflux condenser. 20 parts by weight of n-dodecyl mercaptan and dimethyl 2,
0.1 part by weight of 2'-azobis (2-methylpropionate) was added and reacted at 65 ° C. for 5 hours under a nitrogen atmosphere. As a result, an acrylic low molecular weight polymer having a weight average molecular weight of 3,000 by GPC was obtained.

Production Example 4 Synthesis of acrylic fine powder (resin component): 100 parts by weight of methyl methacrylate, 400 parts by weight of water, polyvinyl in a 1 liter four-necked flask equipped with a thermometer, a nitrogen inlet tube and a reflux condenser 1 part by weight of alcohol, lauryl peroxide 1
After preliminarily emulsifying by charging parts by weight, the temperature was raised to 80 ° C. while stirring in a nitrogen atmosphere to carry out polymerization. As a result, a granular acrylic polymer having a weight average molecular weight of 300,000 as measured by GPC and a volume-based average particle diameter of 6 μm was obtained.

Production Example 5 Synthesis of acrylic fine powder (resin component): 95 parts by weight of methyl methacrylate, 5 parts by weight of methacrylic acid were placed in a 1-liter four-necked flask equipped with a thermometer, a nitrogen inlet tube and a reflux condenser. After 400 parts by weight of water, 1 part by weight of polyvinyl alcohol, and 1 part by weight of lauryl peroxide were charged and pre-emulsified, the temperature was raised to 80 ° C. while stirring in a nitrogen atmosphere to carry out polymerization. As a result, the weight average molecular weight by GPC was 300,0
00, a powdery acrylic polymer having an average particle diameter of 15 μm was obtained.

Production Example 6 Synthesis of acrylic fine powder (resin component): 100 parts by weight of methyl methacrylate, 900 parts by weight of water and 100 parts by weight of water were placed in a 1-liter four-necked flask equipped with a thermometer, a nitrogen inlet tube and a reflux condenser. 1 part by weight of potassium sulfate was charged, and the temperature was raised to 80 ° C. while stirring in a nitrogen atmosphere to carry out polymerization for 3 hours. As a result, a powder-like acrylic polymer obtained by soap-free emulsion polymerization with a weight average molecular weight of 300,000 by GPC, an average particle diameter of 0.6 μm, and the like was obtained.

Example 1 100 parts by weight of the acrylic fine powder of Production Example 4, 65 parts by weight of the acrylic low molecular weight polymer of Production Example 2, and a microcapsule foaming agent (Expancel DU-551; manufactured by Expancel) 5 parts by weight were placed in a container and mixed with stirring to obtain an acrylic sol composition E-1.

Example 2 100 parts by weight of the acrylic fine powder of Production Example 4, 65 parts by weight of the acrylic low molecular weight polymer of Production Example 2, and a pyrolysis type foaming agent (Vinihole FE-788; manufactured by Eiwa Chemical Industry Co., Ltd.) , Azodicarbonamide) 5 parts by weight in a container,
The mixture was stirred and mixed to obtain an acrylic sol composition E-2.

Example 3 100 parts by weight of the acrylic fine powder of Production Example 4, 65 parts by weight of the acrylic low molecular weight polymer of Production Example 2, 5 parts by weight of a microcapsule foaming agent (EXPANCEL DU-551), and N , N, N ', N'-Tetraglycidyl-m-xylylenediamine 0.3 part by weight was placed in a container, and stirred and mixed to obtain an acrylic sol composition E-3.

Example 4 100 parts by weight of the acrylic fine powder of Production Example 4, 65 parts by weight of the acrylic low molecular weight polymer of Production Example 2, 5 parts by weight of a thermal decomposition type foaming agent (Vinihole FE-788), and N, N, N ',
0.3 part by weight of N′-tetraglycidyl-m-xylenediamine is placed in a container, and mixed by stirring to obtain an acrylic sol composition E-4.
I got

Example 5 100 parts by weight of the acrylic fine powder of Production Example 5, 65 parts by weight of the acrylic low molecular weight polymer of Production Example 2, and 5 parts by weight of a microcapsule foaming agent (EXPANCEL DU-551) were placed in a container. After stirring and mixing, an acrylic sol composition E-5 was obtained.

Example 6 100 parts by weight of the acrylic fine powder of Production Example 5, 65 parts by weight of the acrylic low-molecular-weight polymer of Production Example 2, and 5 parts by weight of a pyrolytic foaming agent (Vinihole FE-788) were placed in a container. The mixture was stirred and mixed to obtain an acrylic sol composition E-6.

Example 7 100 parts by weight of the acrylic fine powder of Production Example 5, 65 parts by weight of the acrylic low molecular weight polymer of Example 2, 5 parts by weight of a microcapsule foaming agent (EXPANCEL DU-551), N, N ,
0.3 part by weight of N ', N'-tetraglycidyl-m-xylenediamine is placed in a container, and mixed by stirring.
7 was obtained.

Example 8 100 parts by weight of the acrylic fine powder of Production Example 5, 65 parts by weight of the acrylic low molecular weight polymer of Example 2, 5 parts by weight of a thermal decomposition type foaming agent (Vinihole FE-788), N, N, N 0.3 parts by weight of N ', N'-tetraglycidyl-m-xylenediamine was placed in a container and mixed with stirring to obtain an acrylic sol composition E-8.

Example 9 100 parts by weight of the acrylic fine powder of Production Example 5, 65 parts by weight of the acrylic low molecular weight polymer of Production Example 3, and 5 parts by weight of a microcapsule foaming agent (EXPANCEL DU-551) were placed in a container. The mixture was stirred and mixed to obtain an acrylic sol composition E-9.

Example 10 100 parts by weight of the acrylic fine powder of Production Example 5, 65 parts by weight of the acrylic low molecular weight polymer of Production Example 1, and 5 parts by weight of a microcapsule foaming agent (EXPANCEL DU-551) were placed in a container. After stirring and mixing, an acrylic sol composition E-10 was obtained.

Example 11 100 parts by weight of the acrylic fine powder of Production Example 6, 65 parts by weight of the acrylic low molecular weight polymer of Production Example 2, and 5 parts by weight of a microcapsule foaming agent (EXPANCEL DU-551) were placed in a container. After stirring and mixing, an acrylic sol composition E-11 was obtained.

Example 12 100 parts by weight of the acrylic fine powder of Production Example 5, 50 parts by weight of the acrylic low molecular weight polymer of Production Example 2, 15 parts by weight of diisononyl adipate (DINA), and a microcapsule foaming agent (Expancel DU- 551) 5 parts by weight were placed in a container and mixed by stirring to obtain an acrylic sol composition E-12.

Example 13 100 parts by weight of the acrylic fine powder of Production Example 5, 65 parts by weight of an acrylic low molecular weight polymer (trade name: UP1010, manufactured by Toagosei Co., Ltd .; Mw1,300), microcapsule foaming agent (Expancel) DU-551) 5 parts by weight were placed in a container, and mixed by stirring to obtain an acrylic sol composition E-13.

Comparative Example 1 Comparative Production Example 1 was added to 100 parts by weight of the acrylic fine powder of Production Example 4.
Of acrylic low molecular weight polymer and 5 parts by weight of a microcapsule foaming agent (Expancel DU-551) were placed in a container and mixed to obtain an acrylic sol composition C-1.

Comparative Example 2 100 parts by weight of the fine acrylic powder of Production Example 5, Comparative Production Example 1
65 parts by weight of an acrylic low molecular weight polymer and 5 parts by weight of a heat-decomposable foaming agent (Vinihole FE-788) are placed in a container,
The mixture was mixed to obtain an acrylic sol composition C-2.

Comparative Example 3 100 parts by weight of the acrylic fine powder of Production Example 4 and 65 parts by weight of the acrylic low molecular weight polymer of Production Example 2 were placed in a container and mixed by stirring to obtain an acrylic sol composition C-3.

Comparative Example 4 100 parts by weight of the acrylic fine powder of Production Example 5, 65 parts by weight of dioctyl phthalate (DOP), and 5 parts by weight of the microcapsule foaming agent (EXPANCEL DU-551) of Example 1 were placed in a container. The mixture was mixed to obtain an acrylic sol composition C-4.

Test Example 1 Storage stability of composition: Examples 1 to 13 and Comparative Example 1
Table 1 shows the viscosity (23 ° C., B-type viscometer) of the composition immediately after mixing and the viscosity (23 ° C., B-type viscometer) after standing at 20 ° C. for 3 days for the acrylic sol compositions of Nos. To 4 above.

[0060]

[Table 1]

Example 14 Preparation of Acrylic Sol Molded Product: The acrylic sol composition E-1 obtained in Example 1 was applied on a polyester film having a thickness of 50 μm to a thickness of 0.5 mm, and then applied at 120 ° C. for 5 minutes. The resulting sheet was heated and melted at 130 ° C. for 10 minutes to form a sheet-like foam.

Examples 15 to 26 Preparation of Acrylic Sol Foam: Foams were prepared in the same manner as in Example 14 for the compositions E-2 to 13 obtained in Examples 2 to 13.

Comparative Examples 5 to 8 Preparation of Comparative Acrylic Sol Foams: The sol compositions C-1 to C-4 obtained in Comparative Examples 1 to 4 were foamed in the same manner as in Example 14. Tried. C-1 and C-2 and C-4 could not be formed into a sheet in a sol state even after heating, and C-3 could be formed into a sheet but a foam. I couldn't do that.

Test Example 2 With respect to Examples 14 to 26 and Comparative Example 7, the elongation at break and the strength at break under normal conditions were measured in accordance with JIS K-7127. In addition, the density under normal conditions is determined by JISK-72.
The measurement was performed according to No. 22. The results are shown in the table.

[0065]

[Table 2]

[0066]

According to the acrylic sol composition of the present invention,
It is possible to obtain a foam having excellent sol properties such as dispersibility, compatibility, storage stability, fluidity, and coatability, and excellent.

Moreover, the acrylic sol composition of the present invention and the foam obtained by using the same do not generate halogenated hydrocarbons such as dioxin even when incinerated, and have high safety.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4F074 AA48 AB01 AD13 AD14 AD21 AG02 BA13 BA14 BA16 BA17 BA18 BA19 BA20 BA91 BB07 BB08 BB10 CA21 CB62 CC04Y CC06Y CC42 DA02 DA35 DA39 DA58 4J002 BG041 BG042 BG051 BG051 EU06 016 EV266 FA081 FD022 FD147 FD326 GC00 GL00 GQ01

Claims (10)

[Claims] 1. The following components (A), (B) and (C): (A) 100 parts by weight of an acrylic resin component (B) a weight average molecular weight of 500 to 2,000 containing an acrylic monomer as a main component An acrylic sol composition comprising 10 to 200 parts by weight of a plastic component which is a low-molecular-weight acrylic polymer which is liquid at room temperature (C) 1.0 to 20 parts by weight of a heating type foaming agent. 2. The composition according to claim 1, further comprising a crosslinking agent having two or more functional groups having a reactivity with the functional groups of the acrylic resin component (A) and / or the acrylic monomer (B). The acrylic sol composition according to claim 1, wherein 3. The acrylic sol composition according to claim 1, wherein the resin component (A) is a granular acrylic resin. 4. The acrylic sol composition according to claim 1, wherein the resin component (A) is obtained by a suspension polymerization method or a soap-free emulsion polymerization method. 5. The resin component (A) has a particle size of 0.1 to 20.
μm, weight average molecular weight of 100,000 to 1,000,000
The acrylic sol composition according to claim 4, wherein the acrylic sol composition is a powdery acrylic resin containing methyl methacrylate as a main component. 6. The method according to claim 1, wherein the plastic component (B) is mainly composed of an acrylic resin composed of (meth) acrylate having 1 to 2 carbon atoms in the bonding alkyl group. Acrylic sol composition. 7. The acrylic sol composition according to claim 1, wherein the heating type foaming agent is a microcapsule type foaming agent. 8. The acrylic sol composition according to claim 1, wherein the heating type foaming agent is a pyrolysis type foaming agent. 9. A foam prepared by heating the acrylic sol composition according to any one of claims 1 to 8. 10. The foam according to claim 9, wherein the density is 100 to 500 kg / m ³ .