JPH09302010A - (meth)acrylic resin composition and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a (meth)acrylic resin composition that is low in volume shrinkage when cured and can give an cured product excellent in surface properties, such as surface smoothness and gloss and its manufacture. SOLUTION: The (meth)acrylic resin composition comprises (A) a (math) acrylic syrup made up of a thermosetting (meth)acrylic polymer and a vinyl monomer and (B) at least one polymer selected from the group consisting of a thermoplastic resin, a thermoplastic elastomer, and a rubber with the polymer (B) dispersed in the acrylic syrup (A). Preferably the polymer (B) is a styrene thermoplastic elastomer. The method of producing a (meth)acrylic resin composition comprises dispersing (B) at least one polymer selected from the group consisting of a thermoplastic resin, a thermoplastic elastomer, and a rubber in (A) a (meth)acrylic syrup. Thus, the polymer (B) is dispersed in the (meth) acrylic syrup and when the dispersion is cured, it expands.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a (meth) acrylic resin composition which has a low volumetric shrinkage ratio upon curing and is excellent in surface properties such as surface smoothness and gloss, and its production. It is about the method.

[0002]

2. Description of the Related Art Conventionally, a (meth) acrylic syrup composed of a vinyl monomer and a (meth) acrylic polymer obtained by polymerizing a monomer component containing a (meth) acrylic acid ester is included (meth). Acrylic resin compositions are widely and commonly used as molding materials.

However, the above-mentioned (meth) acrylic resin composition has a relatively large shrinkage upon curing, and pinholes or gloss unevenness may occur in a cured product such as a molded product obtained. That is, the obtained cured product is inferior in surface smoothness and surface properties such as gloss. Further, the above-mentioned (meth) acrylic resin composition has poor dimensional accuracy and poor dimensional stability of the obtained molded product.

Therefore, Japanese Patent Laid-Open No. 6-298883 discloses a (meth) acrylic syrup containing a (meth) acrylic acid ester, a (meth) acrylic polymer and a polyfunctional monomer.
In order to suppress shrinkage at the time of curing, a (meth) acrylic resin composition containing a poorly soluble thermoplastic polymer in the monomer component (vinyl monomer) in the (meth) acrylic syrup is It is disclosed.

[0005]

However, in the above-mentioned conventional (meth) acrylic resin composition, consideration is given to how the thermoplastic polymer is dispersed in the (meth) acrylic syrup. Absent. Also,
The thermoplastic polymers exemplified in the above publication are (meth)
A stable dispersed state cannot be maintained in acrylic syrup, and it tends to be in a dissolved state. Therefore, the shrinkage during curing cannot be sufficiently suppressed. Therefore, the above-mentioned conventional (meth) acrylic resin composition has a problem that the volume shrinkage rate upon curing is not sufficiently reduced, and a cured product having sufficiently excellent surface properties cannot be obtained. ing.
Therefore, there is a demand for a (meth) acrylic resin composition that solves these problems.

The present invention has been made in view of the above-mentioned conventional problems, and an object thereof is to obtain a cured product having a low volume shrinkage ratio upon curing and excellent surface properties such as surface smoothness and gloss. It is intended to provide a (meth) acrylic resin composition capable of producing and a method for producing the same.

[0007]

Means for Solving the Problems The inventors of the present application have made earnest studies on a (meth) acrylic resin composition in order to achieve the above object, and as a result, a thermosetting (meth) acrylic polymer and a vinyl monomer have been obtained. At least one selected from the group consisting of a (meth) acrylic syrup (A) composed of a polymer and a thermoplastic resin, a thermoplastic elastomer, and a rubber.
In a (meth) acrylic resin composition containing a polymer (B) of a kind, the polymer (B) is dispersed in the (meth) acrylic syrup (A) to solve the above problems. As a result, they have found what they can do and completed the present invention.

That is, the (meth) acrylic resin composition according to the invention of claim 1 is composed of a thermosetting (meth) acrylic polymer and a vinyl monomer in order to solve the above-mentioned problems. ) Acrylic syrup (A) and at least one polymer (B) selected from the group consisting of a thermoplastic resin, a thermoplastic elastomer, and rubber, wherein the polymer (B) is a (meth) acrylic syrup. It is characterized by being dispersed in (A).

In order to solve the above-mentioned problems, the (meth) acrylic resin composition according to the second aspect of the present invention is the (meth) acrylic resin composition according to the first aspect.
The polymer (B) is characterized by being a styrene-based thermoplastic elastomer.

According to the above construction, the polymer (B) is dispersed in the (meth) acrylic syrup (A), so that the thermal expansion of the (meth) acrylic resin composition causes the shrinkage of the (meth) acrylic resin composition. It can be efficiently suppressed. As a result, the (meth) acrylic resin composition has a low volume shrinkage at the time of curing, and has excellent surface properties such as surface smoothness and gloss by curing the (meth) acrylic resin composition. Cured product can be obtained.

In order to solve the above problems, the method for producing a (meth) acrylic resin composition according to the third aspect of the present invention comprises a thermosetting (meth) acrylic polymer and a vinyl monomer ( At least one polymer (B) selected from the group consisting of a thermoplastic resin, a thermoplastic elastomer, and rubber is dispersed in the (meth) acrylic syrup (A).

According to the above method, it is possible to produce a (meth) acrylic resin composition having a low volume shrinkage rate upon curing. Further, by curing the above (meth) acrylic resin composition, a cured product having excellent surface properties such as surface smoothness and gloss can be obtained.

Hereinafter, the present invention will be described in detail. In the present invention, “dispersion” means a substance system in which a substance in one phase is dispersed with another substance (dispersed phase) in the form of fine particles. More specifically, dispersion refers to a state where the dispersed substance has a particle size of 1 mm or less and the system is opaque. On the other hand, when the particle size of the scattered substance is the size of the molecule or ion and the system is transparent, the substance is dissolved. Furthermore, "thermosetting" refers to having a property such that viscosity is increased by heating and that a product insoluble in a solvent is generally generated by a crosslinking reaction, and "thermoplastic" is referred to as "thermosetting". Means that the viscosity is reduced and the compound is soluble in at least a specific solvent.

The (meth) acrylic syrup (A) according to the present invention comprises a thermosetting (meth) acrylic polymer and a vinyl monomer.

The thermosetting (meth) acrylic polymer is a polymer containing a structural unit obtained by polymerizing a (meth) acrylic ester, and has a polymerizable double bond in the molecule. Is.

The double bond equivalent of the thermosetting (meth) acrylic polymer, that is, the molecular weight per polymerizable double bond is preferably in the range of 200 to 10,000, and 1,0
More preferably within the range of 00 to 8,000, 2,000
Most preferred is ~ 5,000. Thermosetting (meta)
When the double bond equivalent of the acrylic polymer is less than 200,
It becomes difficult to produce a thermosetting (meth) acrylic polymer. On the other hand, when the double bond equivalent of the thermosetting (meth) acrylic polymer exceeds 10,000, the volume contraction rate of the (meth) acrylic syrup (A) during curing may not be sufficiently reduced. . Further, the cured product obtained by curing the (meth) acrylic resin composition may be inferior in surface smoothness and surface properties such as gloss. Furthermore, by setting the double bond equivalent of the thermosetting (meth) acrylic polymer within the above range, it is possible to suppress the occurrence of cracks in the obtained cured product.

The weight average molecular weight (Mw) of the thermosetting (meth) acrylic polymer is preferably in the range of 3,000 to 500,000, more preferably 5,000 to 100,000, and more preferably 10,000. Most preferably, it is -40,000. When the weight average molecular weight (Mw) of the thermosetting (meth) acrylic polymer is less than 3,000, the physical properties of the cured product of the (meth) acrylic resin composition deteriorate. Weight average molecular weight (Mw) of thermosetting (meth) acrylic polymer is 500,000
When it exceeds, the viscosity of the (meth) acrylic syrup (A) becomes too high, and the workability such as molding work is deteriorated.

As the thermosetting (meth) acrylic polymer according to the present invention, a thermosetting (meth) acrylic polymer having a polymerizable double bond in its side chain is particularly preferable. A thermosetting (meth) acrylic polymer having a polymerizable double bond in its side chain is obtained by polymerizing a monomer component containing a (meth) acrylic acid ester and then adding a polymerizable double bond to the resulting polymer. Obtained by introducing a bond.

Specific examples of the (meth) acrylic acid ester include methyl (meth) acrylate, ethyl (meth) acrylate, and n-propyl (meth) acrylate.
(Meth) such as acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, s-butyl (meth) acrylate, t-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate Acrylic acid alkyl ester; (meth) acrylic acid cycloalkyl ester such as cyclohexyl (meth) acrylate; Dimethylaminoethyl (meth)
Examples thereof include basic (meth) acrylic acid esters such as acrylate and diethylaminoethyl (meth) acrylate, but are not particularly limited. These (meta)
The acrylic acid ester may be used alone, or two or more kinds may be appropriately mixed and used.

Of the above-exemplified compounds, methylmethacrylate and (meth) acrylic acid ester containing methylmethacrylate as a main component are particularly preferable. By using methyl methacrylate as a main component, the cured product obtained by curing the (meth) acrylic resin composition can be further improved in various physical properties such as weather resistance, transparency, surface gloss, appearance, and safety. Can be improved. When a basic (meth) acrylate is used as the (meth) acrylate, 100% by weight or more of the neutral (meth) acrylate is mixed with the basic (meth) acrylate. It is preferable to use them. As the neutral (meth) acrylic acid ester, the above (meth)
An alkyl acrylate, a cycloalkyl (meth) acrylate, or the like can be used.

The above-mentioned monomer component is a (meth) acrylic acid ester containing no hydroxyl group such as the above-mentioned (meth) acrylic acid alkyl ester, (meth) acrylic acid cycloalkyl ester, basic (meth) acrylic acid ester, etc. And a monomer containing a hydroxyl group (hereinafter referred to as a hydroxyl group-containing monomer). Therefore, as the (meth) acrylic acid ester, a mixture of a (meth) acrylic acid ester not containing a hydroxyl group and a (meth) acrylic acid ester containing a hydroxyl group is used, or the monomer component is In addition to the (meth) acrylic acid ester, it is desirable to contain other monomer having a hydroxyl group.

According to the above constitution, the polymer obtained by polymerizing the monomer component is reacted with unsaturated isocyanate, unsaturated acid anhydride or the like to give a thermosetting compound having a double bond in the side chain. A (meth) acrylic polymer can be easily produced. Moreover, by adding a polyfunctional isocyanate or an isocyanate prepolymer to the (meth) acrylic resin composition, the viscosity of the (meth) acrylic resin composition can be easily increased to a viscosity suitable for molding. .

As the above-mentioned hydroxyl group-containing monomer,
There is no particular limitation as long as it is a compound containing a double bond copolymerizable with (meth) acrylic acid ester and a hydroxyl group in one molecule and not containing a carboxyl group. As the hydroxyl group-containing monomer, a (meth) acrylic acid ester containing a hydroxyl group such as glycol (meth) acrylate obtained by esterifying a part of the hydroxyl group of glycol is particularly preferable. Specific examples of the glycol (meth) acrylate include 2-hydroxylethyl (meth)
(Meth) acrylic acid ester having a hydroxyalkyl group such as acrylate and 2-hydroxypropyl (meth) acrylate; glycerin mono (meth) acrylate, glycerin di (meth) acrylate, pentaerythritol mono (meth) acrylate, ventaerythritol di ( (Meth) acrylates of polyhydric alcohols such as (meth) acrylates; (meth) acrylates of high molecular weight glycols such as polyethylene glycol mono (meth) acrylate. As the hydroxyl group-containing monomer, a monomer other than (meth) acrylic acid ester, for example, allyl alcohols such as allyl alcohol, ethylene glycol monoallyl ether, and propylene glycol monoallyl ether may be used. it can. These hydroxyl group-containing monomers may be used alone, or two or more kinds may be appropriately mixed and used.

The proportion of the hydroxyl group-containing monomer in the monomer component is from 0.5% by weight to 20% by weight, with the total of the hydroxyl group-free (meth) acrylic acid ester and the hydroxyl group-containing monomer being 100% by weight. It is preferably in the range of wt%, more preferably in the range of 1 wt% to 15 wt%, and even more preferably in the range of 3 wt% to 10 wt%. When the proportion of the hydroxyl group-containing monomer is less than 0.5% by weight, it is possible to introduce a polymerizable diamine by reacting an unsaturated isocyanate compound with the polymer obtained by polymerizing the monomer component. The number of heavy bonds is limited. On the other hand, if the proportion of the hydroxyl group-containing monomer exceeds 20% by weight, the weather resistance and water resistance of the resulting cured product may be reduced.

The above-mentioned monomer component preferably further contains a monomer containing a carboxyl group (hereinafter referred to as a carboxyl group-containing monomer). According to the above configuration, a thermosetting (meth) acrylic polymer having a double bond in a side chain can be easily prepared by reacting a polymer obtained by polymerizing a monomer component with an unsaturated epoxy compound. Can be manufactured. Moreover, by adding an alkaline earth metal oxide and / or an alkaline earth metal hydroxide to the (meth) acrylic resin composition, the viscosity of the (meth) acrylic resin composition is adjusted to a viscosity suitable for molding. Can be thickened easily.

As the above-mentioned carboxyl group-containing monomer,
There is no particular limitation as long as it is a compound containing a double bond copolymerizable with (meth) acrylic acid ester and a carboxyl group in one molecule. In particular,
For example, unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, crotonic acid and vinylbenzoic acid; unsaturated dicarboxylic acids such as maleic acid, fumaric acid, itaconic acid and citraconic acid; monoesters of these unsaturated dicarboxylic acids; acids Examples thereof include long chain carboxyl group-containing monomers such as anhydride monoesters. Examples of the monoester of the unsaturated dicarboxylic acid include monomethyl maleate, monoethyl maleate, monobutyl maleate, monooctyl maleate, monomethyl fumarate, monoethyl fumarate, monobutyl fumarate, monooctyl fumarate, monoethyl citraconic acid and the like. Is mentioned. Examples of the acid anhydride monoester include succinic acid monoester, phthalic acid monoester, and hexaphthalic acid monoester. These carboxyl group-containing monomers may be used alone, or two or more kinds may be appropriately mixed and used.

The above long-chain carboxyl group-containing monomer can be obtained by esterifying the hydroxyl group of a (meth) acrylic acid ester containing a hydroxyl group with an acid anhydride. Examples of the acid anhydride include succinic anhydride, phthalic anhydride, and hexahydrophthalic anhydride. Examples of the (meth) acrylic acid ester containing a hydroxyl group include 2-hydroxyethyl (meth) acrylate, ε-caprolactone ring-opened adduct to 2-hydroxyethyl (meth) acrylate, or 2-hydroxyethyl (meth) acrylate. A ring-opened adduct of γ-butyrolactone to acrylate and the like can be used.

The amount of the carboxyl group-containing monomer used is
0.5% to 20% by weight, based on the total of (meth) acrylic acid ester and carboxyl group-containing monomer as 100% by weight
Is preferably in the range of 1% to 15% by weight, more preferably 3% to 10% by weight.
It is even more preferable that it is within the range. When the proportion of the carboxyl group-containing monomer is less than 0.5% by weight, it is possible to introduce a polymerizable diamine by reacting an unsaturated epoxy compound with the polymer obtained by polymerizing the monomer component. The number of heavy bonds is limited. On the other hand, when the proportion of the carboxyl group-containing monomer exceeds 20% by weight, the weather resistance and water resistance of the obtained cured product may be deteriorated.

The above-mentioned monomer component optionally contains a vinyl compound (monomer) containing neither a carboxyl group nor a hydroxyl group. The above-mentioned vinyl compound may be a compound containing a double bond copolymerizable with (meth) acrylic acid ester, and specifically, for example, styrene, α-methylstyrene, vinyltoluene,
Styrene-based monomers such as chlorostyrene; vinyl esters such as vinyl acetate; allyl compounds; (meth) acrylamide; (meth) acrylonitrile; N-alkoxy substituted (meth) such as N-methoxymethylacrylamide and N-ethoxymethylacrylamide. Acrylamide; unsaturated basic monomer; maleimide-based monomers such as N-phenylmaleimide, N-cyclohexylmaleimide, N-isopropylmaleimide, etc., but are not particularly limited. These vinyl compounds may be used alone or in combination of two or more.
The mixing ratio of the vinyl compound to the (meth) acrylate when the vinyl compound is mixed, that is, the content of the vinyl compound in the monomer component depends on the type of the vinyl compound and the combination with the (meth) acrylate. Although it depends, it is preferably 50% by weight or less.

When polymerizing the above-mentioned monomer components, it is desirable to use a polymerization initiator. Specific examples of the polymerization initiator include, for example, benzoyl peroxide, lauroyl peroxide, methyl ethyl ketone peroxide, t-butyl peroxy-2-ethylhexanoate, t-butyl peroxy octoate, t- Butyl peroxybenzoate, cumene hydroperoxide,
Cyclohexanone peroxide, dicumyl peroxide, bis (4-t-butylcyclohexyl) peroxydicarbonate, 1,1-bis (t-hexylperoxy) -3,3,
Organic peroxides such as 5-trimethylcyclohexane; 2,2'-
Examples thereof include azo compounds such as azobisisobutyronitrile and 2-phenylazo-2,4-dimethyl-4-methoxyvaleronitrile, but are not particularly limited. These polymerization initiators may be used alone, or two or more of them may be used as an appropriate mixture. The addition amount of the polymerization initiator to the monomer component is not particularly limited.

When polymerizing the above-mentioned monomer components, it is more preferable to add a chain transfer agent in order to adjust the average molecular weight of the polymer. As the chain transfer agent, a thiol compound is preferably used because it controls the polymerization reaction of the monomer component very easily, but is not particularly limited, and α-methylstyrene dimer, carbon tetrachloride, etc. may be used. It can also be used. Specific examples of the thiol compound include alkyl mercaptans such as t-butyl mercaptan, n-octyl mercaptan and n-dodecyl mercaptan; aromatic mercaptans such as thiophenol and thionaphthol; thioglycolic acid; thioglycolic acid Octyl, ethylene glycol dithioglycolate, trimethylolpropane tris- (thioglycolate), pentaerythritol tetrakis- (thioglycolate) and other thioglycolic acid alkyl esters; β-mercaptopropionic acid; β-mercaptopropionic octyl,
Alkyl β-mercaptopropionate such as 1,4-butanediol di (β-thiopropionate), trimethylolpropane tris- (β-thiopropionate), pentaerythritol tetrakis- (β-thiopropionate) Examples thereof include esters, but are not particularly limited. These chain transfer agents may be used alone,
Further, two or more kinds may be appropriately mixed and used. The amount of the chain transfer agent to be used may be selected according to the type of the chain transfer agent, the combination with the (meth) acrylic acid ester and the like, and is not particularly limited, but with respect to the monomer component. A range of 0.1% to 15% by weight is preferred.

When polymerizing the above-mentioned monomer components, a crosslinking agent can be used. The cross-linking agent may be a compound containing a plurality of functional groups that react with the functional groups contained in the monomer component. Specific examples of the cross-linking agent include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, neopentyl glycol di ( (Meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate and other polyfunctional (meth) acrylates; epoxy (meth) acrylates; divinylbenzene, diallylphthalate, diallylisophthalate, triallyl cyanurate , Triallyl isocyanurate and the like, but are not particularly limited. The amount of the cross-linking agent used is not particularly limited as long as it can be set according to the type, the combination with the acrylic ester, the application of the resin material, the desired physical properties, and the like.

The method of polymerizing the monomer component is not particularly limited, but a method of terminating the polymerization of the monomer component, that is, partial polymerization is preferable. By partially polymerizing the monomer component in this way, a mixture of the polymer and the unreacted monomer component is obtained, so that only by introducing a polymerizable double bond into the polymer in the mixture, ( A (meth) acrylic syrup (A) can be obtained. The method for polymerizing the monomer component is not particularly limited, and examples thereof include known polymerization methods such as bulk polymerization, solution polymerization, suspension polymerization, and emulsion polymerization. Bulk polymerization is particularly preferable. preferable. The reaction conditions such as the reaction temperature and the reaction time for performing the above polymerization are not particularly limited, and for example, known reaction conditions can be adopted. The polymerization is preferably carried out under a nitrogen atmosphere.

As described above, a (meth) acrylic polymer containing a structural unit obtained by polymerizing a (meth) acrylic ester and containing no polymerizable double bond (hereinafter simply referred to as a polymer) Is obtained. When a monomer component containing a carboxyl group-containing monomer is polymerized, as the above polymer, a polymer containing a carboxyl group (hereinafter,
A polymer containing a carboxyl group) is obtained. Further, when a monomer component containing a hydroxyl group-containing monomer is polymerized, a polymer containing a hydroxyl group (hereinafter referred to as a hydroxyl group-containing polymer) is obtained as the above polymer. Then, by introducing a polymerizable double bond into the above polymer, a thermosetting (meth) acrylic polymer having a double bond in the side chain can be obtained. Specifically, the carboxyl group-containing polymer can be introduced with a polymerizable double bond by esterification with an unsaturated epoxy compound, for example. Further, the hydroxyl group-containing polymer can be introduced with a polymerizable double bond by, for example, a method of urethanization using an unsaturated isocyanate compound or a method of esterification using an unsaturated acid anhydride. .

As a method of introducing a double bond into the carboxyl group-containing polymer, a method of adding an unsaturated epoxy compound is preferably used. Thereby, the carboxyl group of the carboxyl group-containing polymer opens the epoxy group of the unsaturated epoxy compound to form an ester bond. As a result, a thermosetting (meth) acrylic polymer in which a side chain having a polymerizable double bond is bonded to the main chain via an ester bond is obtained. The carboxyl group-containing polymer to be used may be a mixture with an unreacted monomer component or may be an isolated one.

The unsaturated epoxy compound may be any compound having an epoxy group capable of reacting with a carboxyl group and a polymerizable double bond. Specific examples of the unsaturated epoxy compound include allyl glycidyl ether; glycidyl (meth) acrylate, methyl glycidyl (meth) acrylate; and mono (meth) acrylate of epoxy resin. These compounds may be used alone or in a combination of two or more.

The amount of the unsaturated epoxy compound used may be set according to the combination with the carboxyl group-containing polymer and the like, and is not particularly limited. It is preferably within a range of 0.5 times to 2 times the molar amount of the group-containing monomer, and more preferably within a range of 0.8 times to the 1.5 times molar amount.
When carrying out the above esterification reaction, an esterification catalyst can be added. This allows the esterification reaction to proceed efficiently. The esterification catalyst is not particularly limited as long as it can promote the ring-opening reaction of the epoxy group with the carboxyl group. Specifically, tertiary amines such as dimethylbenzylamine, triethylamine, tetramethylethylenediamine, tri-n-octylamine; quaternary ammonium salts such as tetramethylammonium chloride, tetramethylammonium bromide, tetrabutylammonium bromide; benzyltri Quaternary phosphonium salts such as phenylphosphonium chloride; metal salts and the like. These esterification catalysts may be used alone or in a suitable mixture of two or more kinds.

The addition amount of the esterification catalyst may be set according to the type, combination with the monomer component, etc.,
Although not particularly limited, it is preferably within a range of 0.01 to 5 parts by weight with respect to 100 parts by weight of a reaction mixture obtained by polymerizing a monomer component containing a carboxyl group,
The range of 0.1 to 3 parts by weight is more preferable.

When the above esterification reaction is carried out, a polymerization inhibitor may coexist. As the polymerization inhibitor, hydroquinone, methylhydroquinone, methoxyhydroquinone, tert-butylhydroquinone and the like can be used. A solvent can be used when the esterification reaction is performed. Water and / or an organic solvent can be used as the solvent.

As described above, a thermosetting (meth) acrylic polymer in which a side chain having a polymerizable double bond is bonded to the main chain through an ester bond is obtained.

On the other hand, as a method of introducing a double bond into the hydroxyl group-containing polymer, a method of adding an unsaturated isocyanate compound to form a urethane is preferably used.
Thereby, a thermosetting (meth) acrylic polymer in which a side chain having a polymerizable double bond is bonded to the main chain via a urethane bond is obtained. The hydroxyl group-containing polymer to be used may be a mixture with an unreacted monomer component or may be an isolated one.

The unsaturated isocyanate compound may be a compound having an isocyanate group capable of reacting with a hydroxyl group and a polymerizable double bond. As the unsaturated isocyanate compound, specifically, a reaction product of a polyvalent isocyanate such as isocyanate ethyl methacrylate: tolylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, and the hydroxyl group-containing monomer; m- Isopropenyl-
Examples include α, α-dimethylbenzyl isocyanate. These compounds may be used alone or in a combination of two or more.

The amount of the above-mentioned unsaturated isocyanate compound to be used may be set according to the combination with the hydroxyl group-containing polymer and is not particularly limited, but the hydroxyl group used for the production of the hydroxyl group-containing polymer It is preferably within a range of 0.5 times to 2 times the molar amount of the group-containing monomer, and more preferably within a range of 0.8 times to the 1.5 times molar amount. The above-mentioned solvent, polymerization inhibitor and the like can be used also when carrying out the urethanization reaction.

When carrying out the above-mentioned urethanization reaction, a urethanization catalyst can be added in order to promote the urethanization reaction efficiently. The urethanization catalyst is not particularly limited as long as it can accelerate the urethanization reaction, but dibutyltin dilaurylate is preferable. Only one kind of these urethanization catalysts may be used, or two or more kinds thereof may be appropriately mixed and used.

The amount of the urethanization catalyst added may be set according to the type, combination with the monomer component, etc.,
Although not particularly limited, it is preferably within a range of 0.01 to 5 parts by weight with respect to 100 parts by weight of a reaction mixture obtained by polymerizing a monomer component containing a hydroxyl group,
The range of 0.1 to 3 parts by weight is more preferable.

Further, as a method of introducing a double bond into the hydroxyl group-containing polymer, a method of adding an unsaturated acid anhydride to esterify can also be suitably used. Thereby, a thermosetting (meth) acrylic polymer in which a side chain having a polymerizable double bond is bonded to the main chain via an ester bond is obtained. The hydroxyl group-containing polymer to be used may be a mixture with an unreacted monomer component or may be an isolated one.

The unsaturated acid anhydride may be any acid anhydride capable of reacting with a hydroxyl group and having a polymerizable double bond. Specific examples of the unsaturated acid anhydride include maleic anhydride, itaconic anhydride, citraconic anhydride, and the like. These compounds may be used alone or in a combination of two or more.

The amount of the unsaturated acid anhydride used may be set according to the combination with the hydroxyl group-containing polymer and the like, and is not particularly limited, but it is used for the production of the hydroxyl group-containing polymer. It is preferably within a range of 0.5 times to 2 times the molar amount of the hydroxyl group-containing monomer,
More preferably, it is in the range of twice to 1.5 times the mole. The above-mentioned solvent, polymerization inhibitor and the like can be used also when carrying out the esterification reaction.

When carrying out the esterification reaction of the above-mentioned hydroxyl group-containing polymer, a catalyst can be added in order to allow the esterification reaction to proceed efficiently. The catalyst is not particularly limited as long as it can promote the esterification reaction of the hydroxyl group with the acid anhydride. Specifically, tertiary amines such as dimethylbenzylamine, triethylamine, tetramethylethylenediamine, tri-n-octylamine; quaternary ammonium salts such as tetramethylammonium chloride, tetramethylammonium bromide, tetrabutylammonium bromide; benzyltri Quaternary phosphonium salts such as phenylphosphonium chloride; metal salts and the like. Only one kind of these catalysts may be used, or two or more kinds thereof may be appropriately mixed and used.

The amount of the above catalyst added may be set according to the type and combination with the monomer component and the like, and is not particularly limited, but a monomer component containing a hydroxyl group is polymerized. It is preferably in the range of 0.01 to 2 parts by weight with respect to 100 parts by weight of the reaction mixture obtained.

As described above, a thermosetting (meth) acrylic polymer in which a side chain having a polymerizable double bond is bonded to the main chain through an ester bond can be obtained. When the mixture of the hydroxyl group-containing polymer obtained by partial polymerization of the monomer component and the unreacted monomer component is esterified, it is not reacted with the thermosetting (meth) acrylic polymer. A mixture with the monomer components of

The (meth) acrylic syrup (A) according to the present invention comprises the above-mentioned thermosetting (meth) acrylic polymer and a vinyl monomer.

The vinyl monomer is not particularly limited as long as it is a monomer having a double bond capable of reacting with the double bond of the thermosetting (meth) acrylic polymer. Specific examples of the vinyl monomer include the above-mentioned (meth) acrylate, a carboxyl group-containing monomer, and a vinyl compound. Among these, alkyl methacrylate and styrene monomers are particularly preferred. Further, as the alkyl methacrylate, methyl methacrylate, ethyl methacrylate, n-
Propyl methacrylate, n-butyl methacrylate, s-
Butyl methacrylate and t-butyl methacrylate are particularly preferred, and styrene is particularly preferred as the styrene monomer. This makes it possible to further improve various physical properties such as weather resistance, transparency, surface gloss, etc., appearance, and safety of a cured product obtained by curing the (meth) acrylic resin composition. These vinyl monomers may be used alone, or two or more kinds may be appropriately mixed and used.

The vinyl monomer may be the same as or different from the above-mentioned monomer component. Therefore, a mixture of the thermosetting (meth) acrylic polymer obtained by the esterification or urethanization and the unreacted monomer component is suitable as the (meth) acrylic syrup (A) according to the present invention. Can be used for. The (meth) acrylic syrup (A) in which the vinyl monomer is different from the monomer component can be prepared, for example, by mixing the isolated thermosetting (meth) acrylic polymer with the vinyl monomer. can get.

The ratio (ratio) of the thermosetting (meth) acrylic polymer and the vinyl monomer in the (meth) acrylic syrup (A) is 100% by weight of the total amount of both, and the thermosetting (meth) ) Acrylic polymer 7% to 80% by weight
It is preferable to adjust the content of the vinyl monomer within the range of 93 to 20% by weight.

The (meth) acrylic resin composition according to the present invention comprises at least one selected from the group consisting of the (meth) acrylic syrup (A), a thermoplastic resin, a thermoplastic elastomer, and rubber. Polymer (B)
And the polymer (B) is dispersed in the (meth) acrylic syrup (A).

The polymer (B) is dispersed in the (meth) acrylic syrup (A), expands when the (meth) acrylic syrup (A) is heated and cured, and the (meth) acrylic resin composition shrinks. Thermoplastic resin, which can suppress
At least one polymer selected from the group consisting of thermoplastic elastomer and rubber may be used.

Here, the thermoplastic elastomer has a rubber component (soft component) having elasticity and a resin component (hard component) for preventing plastic deformation in its molecular structure, and exhibits rubber elasticity at room temperature. It is a thermoplastic polymer that exhibits plasticity at high temperatures. The thermoplastic resin is a thermoplastic polymer having only a resin component (hard component) in a molecular structure and not exhibiting rubber elasticity at normal temperature. Further, rubber is a polymer that exhibits rubber elasticity at normal temperature and high temperature.

The thermoplastic elastomer may be selected according to the type of (meth) acrylic syrup (A),
Although not particularly limited, styrene / ethylene /
Propylene / styrene copolymer (SEPS), styrene / ethylene / butylene / styrene copolymer (SEB)
S), maleic anhydride modified styrene / ethylene / butylene / styrene copolymer (MA modified SEBS), styrene / isoprene / styrene copolymer (SIS), styrene / butadiene / styrene copolymer (SBS), styrene / ethylene -Styrene-based thermoplastic elastomer such as propylene copolymer (SEP); polyester-based thermoplastic elastomer; polybutadiene-based thermoplastic elastomer and the like. Of these, styrene-based thermoplastic elastomers are particularly preferred. The styrene content of the styrene-based thermoplastic elastomer is 10 to 25 when the vinyl monomer contained in the (meth) acrylic syrup (A) is methyl methacrylate and / or styrene.
% Is preferable, and 13-20% is more preferable. When the vinyl monomer contained in the (meth) acrylic syrup (A) is a monomer other than methyl methacrylate and styrene, for example, t-butyl methacrylate, the styrene content of the styrene-based thermoplastic elastomer is , 10 to 40% is preferable, and 13 to 30% is more preferable. This allows the thermoplastic elastomer to be more stably dispersed in the (meth) acrylic syrup (A), so that the (meth) acrylic syrup (A) can be efficiently expanded during heat curing. Therefore, the shrinkage of the (meth) acrylic resin composition can be suppressed more efficiently. One of these thermoplastic elastomers may be used alone, or two or more of them may be appropriately mixed and used. The styrene-based thermoplastic elastomer may be linear or radial.

The thermoplastic resin may be selected according to the type of the (meth) acrylic syrup (A) and is not particularly limited, but acid-modified polyvinyl acetate (acid-modified PVAc), vinyl chloride- Vinyl acetate copolymer (VCl
-VAc), ethylene-vinyl acetate copolymer (EV
A), cellulose acetate butyrate (CAB), acrylonitrile / ethylene propylene diene rubber / styrene copolymer (AES), acrylic rubber / acrylonitrile / styrene copolymer (AAS), and the like. Only one kind of these thermoplastic resins may be used, or two or more kinds thereof may be appropriately mixed and used.

The above-mentioned rubber may be selected according to the kind of the (meth) acrylic syrup (A) and is not particularly limited, but styrene-butadiene rubber (SB
R), hydrogenated styrene-butadiene rubber (HSB
R), nitrile-butadiene rubber (NBR), butadiene rubber (BR), diene rubber such as natural rubber and isoprene rubber; chloroprene rubber; butyl rubber; ethylene-propylene rubber; acrylic rubber (ACM); urethane rubber and the like. . One type of these rubbers may be used, or two or more types may be appropriately mixed and used.

The glass transition temperature (hereinafter Tg) of at least one polymer (B) (hereinafter simply referred to as polymer (B)) selected from the group consisting of the above-mentioned thermoplastic resin, thermoplastic elastomer and rubber. ) Is -100 ℃ ~ 80 ℃
Is preferred, -70 ° C to 30 ° C is more preferred, and -60 ° C to 0 ° C is most preferred. When the Tg of the polymer (B) is less than -100 ° C, the surface gloss of the cured product obtained by curing the (meth) acrylic resin composition is lowered. On the other hand, the Tg of the polymer (B) is
When it exceeds 80 ° C, the polymer (B) is less likely to thermally expand,
The effect of reducing the shrinkage of the (meth) acrylic resin composition becomes insufficient. In the present invention, the Tg of the polymer (B) is
In the case where the polymer (B) is a thermoplastic elastomer, the term Tg means the Tg of the rubber component, that is, the Tg on the low temperature side.

The polymer (B) is preferably added in an amount of 2 to 50% by weight, based on 100 parts by weight of the total of the (meth) acrylic syrup (A) and the polymer (B).
It is more preferably 30% by weight, and most preferably 10 to 20% by weight. When the addition amount of the polymer (B) is less than 2% by weight, the effect of suppressing the shrinkage of the (meth) acrylic resin composition becomes insufficient. Therefore, the volume shrinkage at the time of curing cannot be sufficiently reduced, and a cured product having excellent surface properties may not be obtained. On the other hand, if the amount of the polymer (B) added exceeds 50% by weight, the viscosity will increase excessively and it will be difficult to prepare a compound.

The polymer (B) may be dispersed in the (meth) acrylic syrup (A), but the particle size is 5 nm.
It is preferable that a dispersed phase having a particle size of ˜800 μm is formed, it is more preferable that a dispersed phase having a particle size of 50 nm to 500 μm is formed, and it is further preferable that a dispersed phase having a particle size of 100 nm to 100 μm be formed. preferable.

A dispersion stabilizer is added to the (meth) acrylic resin composition according to the present invention in order to stabilize the state in which the polymer (B) is dispersed in the (meth) acrylic syrup (A). Good. This allows a wider range of combinations of (meth) acrylic syrup (A) and polymer (B). The dispersion stabilizer has a portion having a high affinity with (meth) acrylic syrup (A) in the molecule,
Any polymer may be used as long as it has a portion having a high affinity for the polymer (B). Specifically, for example, when the (meth) acrylic syrup (A) contains (meth) acrylic acid ester as a main component and the polymer (B) is a styrene-based thermoplastic elastomer, styrene-vinyl acetate copolymer Coalescence and styrene / methyl methacrylate copolymers are suitable.

As the method for dispersing the polymer (B) in the (meth) acrylic syrup (A) according to the present invention, the polymer (B) is added to the (meth) acrylic syrup (A) and stirred. Polymer (B) is added to the above-mentioned monomer component and stirred, and then partially polymerized; Polymer (B) is added to the vinyl monomer and stirred, and then thermosetting (meth) acrylic A method of adding a system polymer; a method of adding a polymer (B) to a vinyl monomer, stirring the mixture, and then adding a (meth) acrylic syrup (A) can be used. Among these methods, the method in which the polymer (B) is added to the (meth) acrylic syrup (A) and stirred is the most convenient and efficient method for producing the (meth) acrylic resin composition, because the method is most convenient for production. ,preferable. In the above method, the stirring is performed, for example, using a high-speed stirrer at a stirring speed of about 10,000 rpm. Further, the stirring time may be appropriately selected according to the stirring speed and the like, but is preferably 1 minute or more, and more preferably 10 minutes or more.

When used as a molding material, the (meth) acrylic resin composition according to the present invention may optionally contain a thickener, a succinic acid derivative, a reinforcing material and the like. In the following description, components other than the reinforcing material in the (meth) acrylic resin composition will be referred to as compounds.

Examples of the above-mentioned thickeners include alkaline earth metal oxides such as magnesium oxide and calcium oxide; alkaline earth metal hydroxides such as magnesium hydroxide and calcium hydroxide; tetramethylene diisocyanate and hexane. Methylene diisocyanate, 1,4-cyclohexane diisocyanate, xylylene diisocyanate,
Diisocyanates such as 2,4-tolylene diisocyanate;
Polyfunctional isocyanates such as polymethylene polyphenyl isocyanate; isocyanate prepolymers obtained by reacting a terminal hydroxyl group of a polyester polyol or a polyether polyol with a diisocyanate compound to add an isocyanate group to the terminal, but are not particularly limited is not. When the thermosetting (meth) acrylic polymer in the (meth) acrylic syrup (A) contains a carboxyl group, it is preferable to use an alkaline earth metal oxide and / or an alkaline earth metal hydroxide. More preferable. Only one kind of these thickeners may be used, or two or more kinds thereof may be appropriately mixed and used.

The amount of the thickener used depends on the type and combination of the (meth) acrylic syrup (A) and the use of the (meth) acrylic resin composition. The amount is preferably 10 parts by weight or less with respect to 100 parts by weight. By using the thickening agent within the above range, the viscosity of the compound after thickening can be set to a predetermined value suitable for molding work and the like. When the amount of the thickener used is more than 10 parts by weight, the viscosity of the compound after thickening becomes too high and the workability such as molding work is deteriorated, and the weatherability and water resistance of the obtained molded product are reduced. May decrease.

The above-mentioned succinic acid derivative has a function of suppressing an excessive thickening behavior by the thickener, particularly an initial thickening behavior. The succinic acid derivative has a succinic acid skeleton or a succinic anhydride skeleton in the molecule, and the ethylene group of the skeleton has an alkyl group, an alkenyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or the like. Any compound having a substituent may be used, and is not particularly limited. However, a compound having 8 to 30 carbon atoms is preferable. A succinic acid derivative having a total carbon number of 7 or less has poor solubility in a (meth) acrylic resin composition, especially in a (meth) acrylic syrup (A). In addition, the succinic acid derivative having a total carbon number of 31 or more has the expected action by using the succinic acid derivative.
The effect becomes poor. That is, the effect of suppressing the excessive thickening behavior by the thickener is low.

Specific examples of the succinic acid derivative include hexylsuccinic acid, heptylsuccinic acid, octylsuccinic acid, nonylsuccinic acid, decylsuccinic acid, dodecylsuccinic acid, tetradecylsuccinic acid, pentadecylsuccinic acid, and hexadecyl. Compounds having an alkyl group having 4 or more carbon atoms such as succinic acid, heptadecyl succinic acid, octadecyl succinic acid, pentadodecyl succinic acid, eicosyl succinic acid; hexenyl succinic acid, heptenyl succinic acid, octenyl succinic acid, nonenyl succinic acid, decenyl succinic acid , Dodecenyl succinic acid, tetradecenyl succinic acid, pentadecenyl succinic acid, hexadecenyl succinic acid, heptadecenyl succinic acid, octadecenyl succinic acid, pentadodecenyl succinic acid, eicosenyl Having an alkenyl group such as succinic acid Compounds having an alicyclic hydrocarbon group such as cyclododecylsuccinic acid and cyclododecenylsuccinic acid; Compounds having an aromatic hydrocarbon group such as diphenylbutenylsuccinic acid; and anhydrides of these succinic acids However, there is no particular limitation. These succinic acid derivatives may be used alone or as a mixture of two or more. The method for preparing the succinic acid derivative is not particularly limited.

The amount of the succinic acid derivative added depends on the kind and
Depending on the combination of the (meth) acrylic syrup (A) and the thickener, the use of the (meth) acrylic resin composition, etc., 0.01 part by weight relative to 100 parts by weight of the (meth) acrylic syrup (A) The range of 10 to 10 parts by weight is preferable. When the added amount of the succinic acid derivative is less than 0.01 parts by weight, the expected action and effect obtained by using the succinic acid derivative become poor. In other words, the effect of suppressing the excessive thickening behavior of the thickener may be poor. If the amount of the succinic acid derivative is more than 10 parts by weight, the viscosity of the compound after thickening may not reach a predetermined value suitable for molding operation or the like, or may have a long time before reaching. is there.

Specific examples of the reinforcing material include inorganic fibers such as glass fibers, carbon fibers, metal fibers, fibers made of ceramics, organic fibers made of aramid or polyester, and natural fibers. However, it is not particularly limited. Examples of the form of the fiber include roving, cloth, mat, woven fabric, chopped roving, and chopped strand, but are not particularly limited. These reinforcing materials may be used alone, or two or more of them may be appropriately mixed and used.
The amount of the reinforcing material to be used may be set according to the type, the combination with the (meth) acrylic syrup (A), the use of the (meth) acrylic resin composition, the desired physical properties, etc., and is not particularly limited. Not something. The method of mixing the reinforcing material and the compound is not particularly limited, and may be appropriately set depending on the form of the reinforcing material. For example, when the form of the reinforcing material is a mat, cloth, or the like, the reinforcing material may be impregnated with a compound. Further, for example, when the form of the reinforcing material is roving or chopped strands, the reinforcing material and the compound may be kneaded. The (meth) acrylic resin composition containing a reinforcing material is suitable as, for example, a sheet molding compound (hereinafter referred to as SMC) or a bulk molding compound (hereinafter referred to as BMC).

The (meth) acrylic resin composition according to the present invention preferably contains a curing agent (polymerization initiator), and if necessary, a filler, a crosslinkable monomer and an additive. Etc. may be further included. Examples of the above-mentioned curing agent include, but are not particularly limited to, the above-exemplified polymerization initiators used in producing the (meth) acrylic syrup (A). The amount of the curing agent added may be set according to the type and combination with the (meth) acrylic syrup (A), and is not particularly limited, but the (meth) acrylic syrup (A) 100
The range of 0.1 to 5 parts by weight is suitable for the parts by weight.

Specific examples of the above-mentioned filler include aluminum hydroxide, calcium carbonate, barium sulfate, alumina, clay, talc, milled fiber, silica sand, river sand, diatomaceous earth, mica powder, gypsum, cold water sand, Examples thereof include inorganic fillers such as asbestos powder and glass powder, and organic fillers such as polymer beads, but are not particularly limited. These fillers may be used alone,
Further, two or more kinds may be appropriately mixed and used. The form such as the average particle size of the filler is not particularly limited.

The amount of the filler to be blended may be set according to its type, the combination with the (meth) acrylic syrup (A), the use of the (meth) acrylic resin composition, the desired physical properties, and the like. Although not particularly limited, a range of 30 parts by weight to 600 parts by weight is suitable for 100 parts by weight of (meth) acrylic syrup (A). When the (meth) acrylic resin composition is used as SMC, the compounding amount of the filler is in the range of 30 parts by weight to 300 parts by weight with respect to 100 parts by weight of the (meth) acrylic syrup (A). The inside is more preferable. When the (meth) acrylic resin composition is used as BMC, the blending amount of the filler is
For (meth) acrylic syrup (A) 100 parts by weight,
The range of 150 to 600 parts by weight is more preferable. When the (meth) acrylic resin composition is used as a casting material, the content of the filler is in the range of 30 parts by weight to 250 parts by weight with respect to 100 parts by weight of the (meth) acrylic syrup (A). The inside is more preferable. When the (meth) acrylic resin composition is used as a molding material for pultrusion molding,
The blending amount of the filler is (meth) acrylic syrup (A) 10
The range of 10 to 200 parts by weight is more preferable with respect to 0 parts by weight.

The above-mentioned crosslinkable monomer has a function of increasing the crosslink density of the cured product. The crosslinkable monomer may be a compound containing a plurality of functional groups that react with the functional groups contained in the resin composition. Specific examples of the crosslinkable monomer include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, neopentyl. Polyfunctional (meth) acrylates such as glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate; epoxy (meth) acrylates;
Examples thereof include, but are not limited to, divinylbenzene, diallyl phthalate, diallyl isophthalate, triallyl cyanurate and triallyl isocyanurate. The addition amount of the crosslinkable monomer may be set according to the type, the combination with the resin composition, etc., the application of the resin material, the desired physical properties, etc., and is not particularly limited.

As the above-mentioned additive, various kinds of commonly used additives can be adopted and are not particularly limited. For example, (internal) release agent, colorant, polymerization inhibitor, etc. Is mentioned. These additives may be appropriately added depending on, for example, the use of the resin material and desired physical properties. The amount of the additive added may be set according to the type of the additive, the combination with the resin composition and the like, and is not particularly limited.

Specific examples of the releasing agent include stearic acid, zinc stearate, aluminum stearate, calcium stearate, barium stearate, stearic acid amide, triphenyl phosphate, and the like.
Alkyl phosphates include generally used waxes and release agents such as silicone oil. Examples of the colorant include known inorganic pigments and organic pigments.

As described above, the (meth) acrylic resin composition according to the present invention comprises a (meth) acrylic syrup (A) composed of a thermosetting (meth) acrylic polymer and a vinyl monomer, and At least one selected from the group consisting of thermoplastic resin, thermoplastic elastomer, and rubber
The polymer (B) is contained, and the polymer (B) is dispersed in the (meth) acrylic syrup (A). According to the above configuration, the volume shrinkage upon curing is low, the surface smoothness,
A cured product having excellent surface properties such as gloss can be obtained.

The (meth) acrylic resin composition having the above constitution is suitable as a molding material such as a pressure molding material such as SMC or BMC, a premix material, a casting material, a drawing material, an extrusion molding material or the like.

The SMC can be easily manufactured by using a so-called SMC manufacturing apparatus. BMC can be easily manufactured using a kneader such as a double-arm kneader. The casting material can be easily manufactured using a mixer. Then, the SMC is made into a molded product by, for example, heat and pressure molding (press molding) or injection molding at 60 ° C to 160 ° C. Further, BMC is made into a molded product by, for example, heating and pressurizing (press molding) or injection molding at 60 ° C to 160 ° C. The casting material may be, for example, room temperature to 70
A molded product is obtained by injecting (casting) into the cell at ℃. The pultrusion material is formed into a molded product by, for example, pultrusion at 60 to 160 ° C. The resin transfer molding material is made into a molded product by, for example, resin transfer molding at 60 to 160 ° C. The method of curing the resin material is not particularly limited. Further, the resin material according to the present invention can be applied to various molding methods.

The molded product obtained by molding the (meth) acrylic resin composition according to the present invention has excellent surface properties such as surface smoothness and gloss, and excellent dimensional stability. Therefore,
The above-mentioned molded articles are, for example, so-called daylighting domes, benches, tables, tanks, public notice boards, waterproof boards, and various other articles used outdoors; -External material for structures such as walls; artificial marble suitable for bathtubs and kitchen counters; and can be suitably used for electric parts and the like.

[0084]

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. In the Examples and Comparative Examples, “parts” means “parts by weight”, and “%” means “% by weight”.
Is shown. Further, the Tg described in the examples is the Tg on the low temperature side (Tg of the rubber component) of the two Tgs when the polymer (B) is a thermoplastic elastomer.

Example 1 A separable flask equipped with a cooler, a thermometer, a nitrogen gas introducing tube and a stirrer was charged with methyl methacrylate as a (meth) acrylic acid ester.
82 parts and 16 parts of methacrylic acid as a carboxyl group-containing monomer were charged, and after nitrogen substitution in the flask, 15 parts of n-dodecyl mercaptan as a chain transfer agent and 2,2 'as a polymerization initiator. -Azobisisobutyronitrile 0.
03 parts were charged and the temperature was raised to 80 ° C. to carry out polymerization. Then, when the solid content concentration of the reaction liquid in the flask reached 50%, 13.2 parts of glycidyl methacrylate as an unsaturated epoxy compound, 0.05 part of benzyltriphenylphosphonium chloride as an esterification catalyst, and as a polymerization inhibitor. After adding 0.02 part of hydroquinone and quenching, the temperature was raised to 100 ° C., and the esterification reaction was carried out in an air atmosphere for 15 hours. Thereby, the (meth) acrylic syrup (A) according to the present invention was obtained. Obtained (meta)
Acrylic syrup (A) has a viscosity at 25 ° C of 19 poise,
The acid value was 20, the solid content concentration was 50%, and the weight average molecular weight of the thermosetting (meth) acrylic polymer in the (meth) acrylic syrup (A) was 8,300.

The double bond equivalent of the thermosetting (meth) acrylic polymer in the (meth) acrylic syrup (A) was measured. That is, first, when the acid value of the thermosetting (meth) acrylic polymer in the syrup before and after the reaction with glycidyl methacrylate was measured, the difference was 26.5. From this difference in acid value, the number of moles of the disappeared carboxyl group per 1 g of the thermosetting (meth) acrylic polymer was calculated, and this was calculated as the polymerizable double number in 1 g of the thermosetting (meth) acrylic polymer. The number of moles of bond was used. Then, this value was multiplied by the weight average molecular weight of the thermosetting (meth) acrylic polymer to calculate the double bond equivalent. As a result, in this (meth) acrylic syrup (A), the double bond equivalent was about 2000.

Next, 80 parts of the obtained (meth) acrylic syrup (A) was added to styrene as the polymer (B).
Ethylene / Propylene / Styrene Copolymer (Kuraray Co., Ltd. “Septon 2005”, styrene content 20%, T
(g = -53 [deg.] C.) 20 parts was added, and the mixture was stirred at 10,000 rpm for 10 minutes using a high-speed stirrer (Homo Mixer manufactured by Tokushu Kako K.K.). The resulting dispersion was opaque and had a particle size measuring device (“N Scientific Co., Ltd.
ICOMP370 "), the particle size of the dispersed phase was measured and found to be 50 nm to 100 µm. Furthermore, 1,1-bis (t-hexylperoxy) -3,
3,5-Trimethylcyclohexane (Nippon Oil & Fat Co., Ltd. "Perhexa TMH", 10-hour half-life temperature 86.7 ° C) 1
Parts, 100 parts of aluminum hydroxide (“Hijilite H-320” manufactured by Showa Denko KK) as a filler, and 1.67 parts of magnesium oxide as a thickener. Thus, the (meth) acrylic resin composition according to the present invention was obtained.

The obtained (meth) acrylic resin composition was
After aging at 40 ° C for 1 day, 1 g of the obtained thickened product was
Put into a cylinder with a diameter of 11.3mm heated to 20 ℃, cover the bottom of the cylinder, and use a piston from the top to 20kgf / cm ²
It was cured so that the thickened product did not leak under the pressure of. The volume shrinkage at that time was measured and found to be 3.0%. No pinholes or gloss were found on the surface of the cured product thus obtained, and good surface properties were exhibited. Further, when the cured product was cut into two and its cross section was observed with a scanning electron microscope, many voids with a diameter of about 30 μm were observed in the center of the cured product.

Table 1 shows a summary of the above main results.

Example 2 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 1 was used, and styrene / isoprene / styrene copolymer (Shell Chemical Co., Ltd.) as the polymer (B) was used. Company-made "Clayton D-1320
X ”, styrene content 10%, Tg = −50 ° C.) 20 parts, and high-speed stirrer (Homo Mixer manufactured by Tokushu Kako Co., Ltd.)
Was stirred at 10,000 rpm for 10 minutes. The resulting dispersion was opaque and had a particle size measuring device ("NICOMP370" manufactured by Pacific Scientific Co., Ltd.).
Then, the particle size of the dispersed phase was measured and found to be 50 nm to 100 μm.
Met. Furthermore, the same curing agent, filler, and thickener as in Example 1 were added to this dispersion liquid. This allows
A (meth) acrylic resin composition according to the present invention was obtained.

The obtained (meth) acrylic resin composition was
After aging at 40 ° C for 1 day, the obtained thickened product was cured in the same manner as in Example 1. The volume shrinkage at that time was measured and found to be 3.5%. No pinholes or gloss were found on the surface of the cured product thus obtained, and good surface properties were exhibited. Further, when the cured product was cut into two and its cross section was observed with a scanning electron microscope, many voids with a diameter of about 30 μm were observed in the center of the cured product.

Table 1 shows a summary of the above main results.

Example 3 For 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 1, cellulose acetate butyrate as a polymer (B) (produced by Eastman Chemicals Japan Co., Ltd.) "CAB-5
51-0.01 ", Tg = 40 ° C.) 20 parts and added using a high-speed stirrer (Homo Mixer manufactured by Tokushu Kako Co., Ltd.)
The mixture was stirred at 0,000 rpm for 10 minutes. The obtained dispersion was opaque and the particle size of the dispersed phase was measured with a particle size measuring device (“NICOMP370” manufactured by Pacific Scientific Co., Ltd.), and it was 100 nm to 500 μm. Further, to this dispersion liquid, a curing agent similar to that in Example 1,
Fillers and thickeners were added. Thus, the (meth) acrylic resin composition according to the present invention was obtained.

The obtained (meth) acrylic resin composition was
After aging at 40 ° C for 1 day, the obtained thickened product was cured in the same manner as in Example 1. The volume shrinkage at that time was measured and found to be 4.5%. No pinholes or gloss were found on the surface of the cured product thus obtained, and good surface properties were exhibited. Further, when the cured product was cut into two and its cross section was observed with a scanning electron microscope, many voids with a diameter of about 30 μm were observed in the center of the cured product.

The main results of the above are summarized in Table 1.

Example 4 With respect to 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 1, maleic anhydride-modified styrene / ethylene / butylene / styrene as the polymer (B) was mixed. Polymer (Asahi Kasei "Tuftec M1943", styrene content 20%, Tg
(= −55 ° C.) 20 parts were added, and the mixture was stirred at 10,000 rpm for 10 minutes using a high-speed stirrer (Homo Mixer manufactured by Tokushu Kako K.K.). The resulting dispersion was opaque and had a particle size measuring device (“NI Scientific Instruments“ NI
The particle size of the dispersed phase was measured by COMP370 ") and was found to be 50 nm to 100 µm. Furthermore, the same curing agent, filler, and thickener as in Example 1 were added to this dispersion liquid. Thus, the (meth) acrylic resin composition according to the present invention was obtained.

The obtained (meth) acrylic resin composition was
After aging at 40 ° C for 1 day, the obtained thickened product was cured in the same manner as in Example 1. The volume shrinkage at that time was measured and found to be 3.5%. No pinholes or gloss were found on the surface of the cured product thus obtained, and good surface properties were exhibited. Further, when the cured product was cut into two and its cross section was observed with a scanning electron microscope, many voids with a diameter of about 30 μm were observed in the center of the cured product.

Table 1 summarizes the above main results.

Example 5 To 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 1, styrene-butadiene rubber as a polymer (B) (“Niponol NS112” manufactured by Nippon Zeon Co., Ltd.) was used. , Tg =-
(68 ° C.) (20 parts) was added, and the mixture was stirred at 10,000 rpm for 10 minutes using a high-speed stirrer (Homo Mixer manufactured by Tokushu Kako K.K.). The resulting dispersion was opaque and had a particle size measuring device (“NI Scientific Instruments“ NI
The particle size of the dispersed phase was measured with COMP 370 ″), and it was 100 nm to 500 μm. Furthermore, the same curing agent, filler, and thickener as in Example 1 were added to this dispersion liquid. Thus, the (meth) acrylic resin composition according to the present invention was obtained.

The obtained (meth) acrylic resin composition was
After aging at 40 ° C for 1 day, the obtained thickened product was cured in the same manner as in Example 1. The volume shrinkage at that time was measured and found to be 4.5%. No pinholes or gloss were found on the surface of the cured product thus obtained, and good surface properties were exhibited. Further, when the cured product was cut into two and its cross section was observed with a scanning electron microscope, many voids with a diameter of about 30 μm were observed in the center of the cured product.

The main results of the above are summarized in Table 1.

[0102]

[Table 1]

Example 6 To 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 1, nitrile-butadiene rubber as the polymer (B) (“Niponol DN manufactured by Nippon Zeon Co., Ltd.”) was used. -214 ", Tg =
-22 ° C.) (20 parts) was added, and the mixture was stirred at 10,000 rpm for 10 minutes using a high-speed stirrer (Homo Mixer manufactured by Tokushu Kika Kako Co., Ltd.). The resulting dispersion was opaque and had a particle size measuring device (“NI Scientific Instruments“ NI
The particle size of the dispersed phase was measured with COMP 370 ″), and it was 100 nm to 500 μm. Furthermore, the same curing agent, filler, and thickener as in Example 1 were added to this dispersion liquid. Thus, the (meth) acrylic resin composition according to the present invention was obtained.

The obtained (meth) acrylic resin composition was
After aging at 40 ° C for 1 day, the obtained thickened product was cured in the same manner as in Example 1. The volume shrinkage at that time was measured and found to be 4.7%. No pinholes or gloss were found on the surface of the cured product thus obtained, and good surface properties were exhibited. Further, when the cured product was cut into two and its cross section was observed with a scanning electron microscope, many voids with a diameter of about 30 μm were observed in the center of the cured product.

Table 2 shows a summary of the above main results.

Example 7 To 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 1, styrene / ethylene / propylene / styrene copolymer as polymer (B) (stock) Made by Kuraray Co., Ltd. “Septon 206
3 ", styrene content 13%, Tg = -50 [deg.] C.) 20 parts, and styrene-methyl methacrylate copolymer as a dispersion stabilizer (NOF CORPORATION," MODIPER MS-10 ").
B ") was added, and the mixture was stirred at 10,000 rpm for 10 minutes using a high-speed stirrer (Homo Mixer manufactured by Tokushu Kako K.K.). The resulting dispersion was opaque and had a particle size measuring device (“NI Scientific Instruments“ NI
The particle size of the dispersed phase was measured by COMP370 ") and was found to be 50 nm to 100 µm. Furthermore, the same curing agent, filler, and thickener as in Example 1 were added to this dispersion liquid. Thus, the (meth) acrylic resin composition according to the present invention was obtained.

The obtained (meth) acrylic resin composition was
After aging at 40 ° C for 1 day, the obtained thickened product was cured in the same manner as in Example 1. The volume shrinkage at that time was measured and found to be 3.5%. No pinholes or gloss were found on the surface of the cured product thus obtained, and good surface properties were exhibited. Further, when the cured product was cut into two and its cross section was observed with a scanning electron microscope, many voids with a diameter of about 30 μm were observed in the center of the cured product.

Table 2 shows a summary of the above main results.

Example 8 In a separable flask equipped with a condenser, a thermometer, a nitrogen gas introducing tube and a stirrer, 176.5 parts of methyl methacrylate as a (meth) acrylic acid ester containing no hydroxyl group and a hydroxyl group 2-Hydroxyethyl methacrylate 2 as a containing monomer
After charging 3.5 parts with and replacing the inside of the flask with nitrogen, 14.6 parts of n-dodecyl mercaptan as a chain transfer agent and 2,2'-azobisisobutyronitrile as a polymerization initiator
0.03 parts was added and the temperature was raised to 80 ° C. to carry out polymerization. Then, when the solid content concentration of the reaction liquid in the flask reached 50%, air was blown into the flask to rapidly cool it to stop the polymerization.
When the temperature of the reaction system reached 40 ° C, 18.8 parts of m-isopropenyl-α, α-dimethylbenzyl isocyanate as an unsaturated isocyanate compound, 0.05 part of dibutyltin dilaurate as a urethanization catalyst, and a polymerization inhibitor 0.02 part of hydroquinone was added and the urethanization reaction was carried out for 1 hour in an air atmosphere. After the heat generated by the reaction had subsided, the temperature was raised to 80 ° C., and the urethanization reaction was allowed to proceed for 1 hour in an air atmosphere. Thereby, the (meth) acrylic syrup (A) according to the present invention was obtained. The obtained (meth) acrylic syrup (A) has a viscosity at 25 ° C. of 25 poise, is 27, and has a solid content concentration of 50%, and has a thermosetting property (meth) in the (meth) acrylic syrup (A). The weight average molecular weight of the acrylic polymer is
It was 8,800.

The double bond equivalent of the thermosetting (meth) acrylic polymer in the (meth) acrylic syrup (A) was measured. That is, first, when the hydroxyl value of the thermosetting (meth) acrylic polymer in the syrup before and after the reaction with m-isopropenyl-α, α-dimethylbenzyl isocyanate was measured, the difference was 20. From the difference in the hydroxyl value, the number of moles of the disappeared hydroxyl group per 1 g of the thermosetting (meth) acrylic polymer was calculated,
This was defined as the number of moles of the polymerizable double bond in 1 g of the thermosetting (meth) acrylic polymer. Then, this value was multiplied by the weight average molecular weight of the thermosetting (meth) acrylic polymer to calculate the double bond equivalent. As a result, this (meta)
In the acrylic syrup (A), the double bond equivalent was about 2800.

Next, with respect to 80 parts of the obtained (meth) acrylic syrup (A), acid-modified polyvinyl acetate as a polymer (B) ("DENKA ASR M-" manufactured by Denki Kagaku Co., Ltd.) was used.
5 ”, Tg = 30 ° C.) 20 parts, and a high-speed stirrer (Homo Mixer manufactured by Tokushu Kika Co., Ltd.) at 10,000 rpm for 10
Stir for minutes. The obtained dispersion was opaque, and the particle size of the dispersed phase was measured with a particle size measuring device (“NICOMP370” manufactured by Pacific Scientific Co., Ltd.), and it was 50 nm to 100 μm. Furthermore, the same curing agent, filler, and thickener as in Example 1 were added to this dispersion liquid. Thus, the (meth) acrylic resin composition according to the present invention was obtained.

The obtained (meth) acrylic resin composition was
After aging at 40 ° C for 1 day, the obtained thickened product was cured in the same manner as in Example 1. The volume shrinkage at that time was measured and found to be 3.7%. No pinholes or gloss were found on the surface of the cured product thus obtained, and good surface properties were exhibited. Further, when the cured product was cut into two and its cross section was observed with a scanning electron microscope, many voids with a diameter of about 30 μm were observed in the center of the cured product.

The main results of the above are summarized in Table 2.

Example 9 To 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 1, acrylic rubber as polymer (B) (“Nipol AR31” manufactured by Nippon Zeon Co., Ltd.) was used. , Tg = −15 ° C.) 20 parts, and a high-speed stirrer (Homo Mixer manufactured by Tokushu Kako Co., Ltd.)
Was stirred at 10,000 rpm for 10 minutes. The resulting dispersion was opaque and had a particle size measuring device ("NICOMP370" manufactured by Pacific Scientific Co., Ltd.).
Then, the particle size of the dispersed phase was measured and found to be 100 nm to 500 μ.
m. Furthermore, the same curing agent, filler, and thickener as in Example 1 were added to this dispersion liquid. Thus, the (meth) acrylic resin composition according to the present invention was obtained.

The obtained (meth) acrylic resin composition was
After aging at 40 ° C for 1 day, the obtained thickened product was cured in the same manner as in Example 1. The volume shrinkage at that time was measured and found to be 4.5%. No pinholes or gloss were found on the surface of the cured product thus obtained, and good surface properties were exhibited. Further, when the cured product was cut into two and its cross section was observed with a scanning electron microscope, many voids with a diameter of about 30 μm were observed in the center of the cured product.

The main results of the above are summarized in Table 2.

Example 10 To 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 1, styrene / ethylene / propylene / polymer (B) was added.
Styrene copolymer (Kuraray Co., Ltd. “Septon 200
5 ", styrene content 20%, Tg = -53 ° C) 20 parts, added, high speed stirrer (Homo Mixer manufactured by Tokushu Kika Co., Ltd.)
Was stirred at 10,000 rpm for 1 minute. The obtained dispersion was opaque, and the particle size of the dispersed phase was measured using a particle size measuring device (“NICOMP370” manufactured by Pacific Scientific Co., Ltd.) and an optical microscope, and it was 50 μm to 1.5 mm. there were. Furthermore, the same curing agent, filler, and thickener as in Example 1 were added to this dispersion liquid. Thus, the (meth) acrylic resin composition according to the present invention was obtained.

The obtained (meth) acrylic resin composition was
After aging at 40 ° C for 1 day, the obtained thickened product was cured in the same manner as in Example 1. The volumetric shrinkage at that time was measured and found to be 5.5%. The surface of the cured product thus obtained was slightly inferior in gloss to the cured product obtained in Example 1, but pinholes and gloss unevenness were not observed, and good surface properties were exhibited. Further, when the cured product was cut into two and its cross section was observed with a scanning electron microscope, many voids with a diameter of about 30 μm were observed in the center of the cured product.

The main results of the above are summarized in Table 2.

[0120]

[Table 2]

[Comparative Example 1] A separable flask equipped with a condenser, a thermometer, a nitrogen gas introducing tube and a stirrer was charged with methyl methacrylate as a (meth) acrylic acid ester.
After charging 88 parts and 12 parts of methacrylic acid as a carboxyl group-containing monomer and purging the flask with nitrogen, 1 part of n-dodecyl mercaptan as a chain transfer agent and 2,2 'as a polymerization initiator -Azobisisobutyronitrile 0.
Polymerization was carried out by adding 04 parts and raising the temperature to 80 ° C. Then, when the solid content concentration of the reaction liquid in the flask reached 27%, 0.02 parts of hydroquinone as a polymerization inhibitor and 30 parts of methyl methacrylate were added and quenched to stop the reaction. Thereby, a (meth) acrylic syrup for comparison was obtained. The obtained (meth) acrylic syrup for comparison has a viscosity at 25 ° C of 7 poise, an acid value of 10, and a solid content concentration of
It was 23.5%. Further, the (meth) acrylic polymer in the comparative (meth) acrylic syrup did not have a double bond, and its weight average molecular weight was 61,000.

Next, with respect to 80 parts of the obtained (meth) acrylic syrup for comparison, a styrene / ethylene / propylene / styrene copolymer (“Septon 2 manufactured by Kuraray Co., Ltd.”) was used.
005 ", styrene content 20%) and 20 parts, and using a high speed stirrer (Homo Mixer manufactured by Tokushu Kika Co., Ltd.)
The mixture was stirred at 0,000 rpm for 10 minutes. The obtained dispersion was opaque, and the particle size of the dispersed phase was measured with a particle size measuring device (“NICOMP370” manufactured by Pacific Scientific Co., Ltd.), and it was 50 nm to 100 μm.
Furthermore, the same curing agent, filler, and thickener as in Example 1 were added to this dispersion liquid. Thereby, a (meth) acrylic resin composition for comparison was obtained.

The obtained (meth) acrylic resin composition for comparison was aged at 40 ° C. for 1 day, and then the obtained thickened product was cured in the same manner as in Example 1. When the volumetric shrinkage at that time was measured, it was 14%, and gloss unevenness was observed on the surface of the obtained cured product. Further, when the thus obtained cured product was cut into two and the cross section thereof was observed by a scanning electron microscope, no void was observed.

The main results of the above are summarized in Table 3.

Comparative Example 2 The same curing agent as in Example 1 was added to 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 1 without adding the polymer (B). , Fillers, and thickeners were added. Thereby, a (meth) acrylic resin composition for comparison was obtained.

The obtained (meth) acrylic resin composition for comparison was aged at 40 ° C. for 1 day, and then the obtained thickened product was cured in the same manner as in Example 1. When the volumetric shrinkage at that time was measured, it was 12%, and gloss unevenness was observed on the surface of the obtained cured product. Further, when the thus obtained cured product was cut into two and the cross section thereof was observed by a scanning electron microscope, no void was observed.

Table 3 shows a summary of the above main results.

Comparative Example 3 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 1 was used, and polymethylmethacrylate beads (weight average molecular weight of 950,00) were used.
0) 20 parts was added, and the mixture was stirred at 10,000 rpm for 10 minutes using a high-speed stirrer (Homo Mixer manufactured by Tokushu Kika Kogyo Co., Ltd.), and the obtained mixed solution became a transparent solution. The same curing agent, filler, and thickener as in Example 1 were added to this mixed solution. Thereby, a (meth) acrylic resin composition for comparison was obtained.

The obtained (meth) acrylic resin composition for comparison was aged at 40 ° C. for 1 day, and then the obtained thickened product was cured in the same manner as in Example 1. The volumetric shrinkage at that time was measured and found to be 10%, and gloss was found on the surface of the obtained cured product. Further, when the thus obtained cured product was cut into two and the cross section thereof was observed by a scanning electron microscope, no void was observed.

Table 3 shows a summary of the above main results.

Comparative Example 4 20 parts of polystyrene beads (weight average molecular weight 200,000) were added to 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 1, and a high-speed stirrer (special When the mixture was stirred for 10 minutes at 10,000 rpm using Kika Kogyo Co., Ltd., the obtained mixed solution became a transparent solution. In this mixed solution,
The same curing agent, filler, and thickener as in Example 1 were added. Thereby, a (meth) acrylic resin composition for comparison was obtained.

The obtained (meth) acrylic resin composition for comparison was aged at 40 ° C. for 1 day, and then the obtained thickened product was cured in the same manner as in Example 1. The volumetric shrinkage at that time was measured and found to be 10%, and gloss was found on the surface of the obtained cured product. Further, when the thus obtained cured product was cut into two and the cross section thereof was observed by a scanning electron microscope, no void was observed.

Table 3 shows a summary of the above main results.

[Comparative Example 5] To 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 1, 20 parts of polyvinyl acetate beads (weight average molecular weight 400,000) were added, and a high-speed stirrer was used. After stirring for 10 minutes at 10,000 rpm using (Homo Mixer manufactured by Tokushu Kika Co., Ltd.), the obtained mixed solution became a transparent solution. In this mixed solution,
The same curing agent, filler, and thickener as in Example 1 were added. Thereby, a (meth) acrylic resin composition for comparison was obtained.

The obtained (meth) acrylic resin composition for comparison was aged at 40 ° C. for 1 day, and the obtained thickened product was cured in the same manner as in Example 1. The volumetric shrinkage at that time was measured and found to be 10%, and gloss was found on the surface of the obtained cured product. Further, when the thus obtained cured product was cut into two and the cross section thereof was observed by a scanning electron microscope, no void was observed.

The main results of the above are summarized in Table 3.

[0137]

[Table 3]

Example 11 In a separable flask equipped with a cooler, a thermometer, a nitrogen gas introducing tube and a stirrer,
(Meth) 182 parts of methyl methacrylate as an acrylic ester and 16 parts of methacrylic acid as a carboxyl group-containing monomer were charged, and the inside of the flask was replaced with nitrogen,
15 parts of n-dodecyl mercaptan as a chain transfer agent and 0.03 part of 2,2′-azobisisobutyronitrile as a polymerization initiator were added, and the temperature was raised to 80 ° C. to carry out polymerization. Then, when the solid content concentration of the reaction liquid in the flask reached 50%, 13.2 parts of glycidyl methacrylate as an unsaturated epoxy compound, 0.05 part of benzyltriphenylphosphonium chloride as an esterification catalyst, and as a polymerization inhibitor. After adding 0.02 part of hydroquinone and quenching, the temperature was raised to 100 ° C., and the esterification reaction was carried out in an air atmosphere for 15 hours.

The resulting reaction mixture, ie, (meth) acrylic syrup, was dissolved in three times the weight of acetone with respect to (meth) acrylic syrup and reprecipitated in a large amount of methanol to obtain a polymer component (thermosetting). Only the (meth) acrylic polymer) is removed and placed in a dryer at 60 ° C for 4
Dried for hours. Next, the dried polymer component was dissolved in styrene as a vinyl monomer so that the ratio of the polymer component in the obtained (meth) acrylic syrup was 50%. Thereby, the (meth) acrylic syrup (A) according to the present invention was obtained. The obtained (meth) acrylic syrup (A) has a viscosity at 25 ° C. of 19 poise and an acid value of
15 and the weight average molecular weight of the thermosetting (meth) acrylic polymer in the (meth) acrylic syrup (A) was 8,300.
Met.

The double bond equivalent of the thermosetting (meth) acrylic polymer in the (meth) acrylic syrup (A) was measured. That is, first, when the acid value of the thermosetting (meth) acrylic polymer in the syrup before and after the reaction with glycidyl methacrylate was measured, the difference was 26.5. From this difference in acid value, the number of moles of the disappeared carboxyl group per 1 g of the thermosetting (meth) acrylic polymer was calculated, and this was calculated as the polymerizable double number in 1 g of the thermosetting (meth) acrylic polymer. The number of moles of bond was used. Then, this value was multiplied by the weight average molecular weight of the thermosetting (meth) acrylic polymer to calculate the double bond equivalent. As a result, in this (meth) acrylic syrup (A), the double bond equivalent was about 2000.

Obtained (meth) acrylic syrup (A)
For 80 parts, cellulose acetate butyrate (“CAB-551-0.01” manufactured by Eastman Chemicals Japan Co., Tg = 40 ° C.) as polymer (B) 20
Parts were added, and the mixture was stirred at 10,000 rpm for 10 minutes using a high-speed stirrer (Homo Mixer manufactured by Tokushu Kako Co., Ltd.). The resulting dispersion was opaque and had a particle size measuring device ("NICOMP37" manufactured by Pacific Scientific Co., Ltd.).
0 ”), the particle size of the dispersed phase was measured to be 100 nm-
It was 500 μm. Furthermore, the same curing agent, filler, and thickener as in Example 1 were added to this dispersion liquid. Thus, the (meth) acrylic resin composition according to the present invention was obtained.

The obtained (meth) acrylic resin composition was
After aging at 40 ° C for 1 day, the obtained thickened product was cured in the same manner as in Example 1. The volume shrinkage at that time was measured and found to be 4.5%. No pinholes or gloss were found on the surface of the cured product thus obtained, and good surface properties were exhibited. Further, when the cured product was cut into two and its cross section was observed with a scanning electron microscope, many voids with a diameter of about 30 μm were observed in the center of the cured product.

The main results of the above are summarized in Table 4.

Example 12 For 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 11,
Ethylene / vinyl acetate copolymer as polymer (B) ("Ultrasen 625" manufactured by Tosoh Corporation, Tg =-
(20 ° C.) 20 parts was added, and the mixture was stirred at 10,000 rpm for 10 minutes using a high-speed stirrer (Homo Mixer manufactured by Tokushu Kako K.K.). The resulting dispersion was opaque and had a particle size measuring device (“NI Scientific Instruments“ NI
The particle size of the dispersed phase was measured by COMP370 ") and found to be 100 nm to 500 µm. Furthermore, the same curing agent, filler, and thickener as in Example 1 were added to this dispersion liquid. Thus, the (meth) acrylic resin composition according to the present invention was obtained.

The obtained (meth) acrylic resin composition was
After aging at 40 ° C for 1 day, the obtained thickened product was cured in the same manner as in Example 1. The volume shrinkage at that time was measured and found to be 4.7%. No pinholes or gloss were found on the surface of the cured product thus obtained, and good surface properties were exhibited. Further, when the cured product was cut into two and its cross section was observed with a scanning electron microscope, many voids with a diameter of about 30 μm were observed in the center of the cured product.

The main results of the above are summarized in Table 4.

Example 13 For 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 11,
Vinyl chloride / vinyl acetate copolymer as the polymer (B) ("Luron TC-806" manufactured by Tosoh Corporation, Tg
(= 60 ° C.) was added, and the mixture was stirred at 10,000 rpm for 10 minutes using a high-speed stirrer (Homo Mixer manufactured by Tokushu Kika Kako Co., Ltd.). The resulting dispersion was opaque and had a particle size measuring device (“NI Scientific Instruments“ NI
The particle size of the dispersed phase was measured by COMP370 ") and was found to be 50 nm to 100 µm. Furthermore, the same curing agent, filler, and thickener as in Example 1 were added to this dispersion liquid. Thus, the (meth) acrylic resin composition according to the present invention was obtained.

The obtained (meth) acrylic resin composition was
After aging at 40 ° C for 1 day, the obtained thickened product was cured in the same manner as in Example 1. The volume shrinkage at that time was measured and found to be 4.0%. No pinholes or gloss were found on the surface of the cured product thus obtained, and good surface properties were exhibited. Further, when the cured product was cut into two and its cross section was observed with a scanning electron microscope, many voids with a diameter of about 30 μm were observed in the center of the cured product.

The main results of the above are summarized in Table 4.

Example 14 With respect to 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 11,
Hydrogenated styrene-butadiene rubber as polymer (B) (“Dyalon 1320 manufactured by Japan Synthetic Rubber Co., Ltd.”
P ”, styrene content 10%, Tg = −50 ° C.) 20 parts, and high-speed stirrer (Homo Mixer manufactured by Tokushu Kako Co., Ltd.)
Was stirred at 10,000 rpm for 10 minutes. The resulting dispersion was opaque and had a particle size measuring device ("NICOMP370" manufactured by Pacific Scientific Co., Ltd.).
Then, the particle size of the dispersed phase was measured and found to be 50 nm to 100 μm.
Met. Furthermore, the same curing agent, filler, and thickener as in Example 1 were added to this dispersion liquid. This allows
A (meth) acrylic resin composition according to the present invention was obtained.

The obtained (meth) acrylic resin composition was
After aging at 40 ° C for 1 day, the obtained thickened product was cured in the same manner as in Example 1. The volume shrinkage at that time was measured and found to be 4.0%. No pinholes or gloss were found on the surface of the cured product thus obtained, and good surface properties were exhibited. Further, when the cured product was cut into two and its cross section was observed with a scanning electron microscope, many voids with a diameter of about 30 μm were observed in the center of the cured product.

The main results of the above are summarized in Table 4.

Example 15 With respect to 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 11,
Maleic anhydride-modified styrene / ethylene / butylene / styrene copolymer as polymer (B) (“Tuftec M1943” manufactured by Asahi Kasei Corporation, styrene content 20%, T
g = -55 ° C.) 20 parts was added, and the mixture was stirred at 10,000 rpm for 10 minutes using a high-speed stirrer (Homo Mixer manufactured by Tokushu Kako Co., Ltd.). The resulting dispersion was opaque and had a particle size measuring device (“N Scientific Co., Ltd.
ICOMP370 "), the particle size of the dispersed phase was measured and found to be 50 nm to 100 µm. Furthermore, the same curing agent, filler, and thickener as in Example 1 were added to this dispersion liquid. Thus, the (meth) acrylic resin composition according to the present invention was obtained.

The obtained (meth) acrylic resin composition was
After aging at 40 ° C for 1 day, the obtained thickened product was cured in the same manner as in Example 1. The volume shrinkage at that time was measured and found to be 4.2%. No pinholes or gloss were found on the surface of the cured product thus obtained, and good surface properties were exhibited. Further, when the cured product was cut into two and its cross section was observed with a scanning electron microscope, many voids with a diameter of about 30 μm were observed in the center of the cured product.

Table 4 shows a summary of the above main results.

Example 16 To 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 11,
Styrene-butadiene rubber as polymer (B) (“Niponol NS112” manufactured by Nippon Zeon Co., Ltd., Tg
(= −68 ° C.) 20 parts were added, and the mixture was stirred at 10,000 rpm for 10 minutes using a high-speed stirrer (Homo Mixer manufactured by Tokushu Kako Co., Ltd.). The resulting dispersion was opaque and had a particle size measuring device (“NI Scientific Instruments“ NI
The particle size of the dispersed phase was measured by COMP370 ") and was found to be 50 nm to 100 µm. Furthermore, the same curing agent, filler, and thickener as in Example 1 were added to this dispersion liquid. Thus, the (meth) acrylic resin composition according to the present invention was obtained.

The obtained (meth) acrylic resin composition was
After aging at 40 ° C for 1 day, the obtained thickened product was cured in the same manner as in Example 1. The volume shrinkage at that time was measured and found to be 4.0%. No pinholes or gloss were found on the surface of the cured product thus obtained, and good surface properties were exhibited. Further, when the cured product was cut into two and its cross section was observed with a scanning electron microscope, many voids with a diameter of about 30 μm were observed in the center of the cured product.

The main results of the above are summarized in Table 4.

Example 17 With respect to 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 11,
Nitrile butadiene rubber as polymer (B) (“Niponol DN-214” manufactured by Nippon Zeon Co., Ltd., T
(g = -22 ° C) 20 parts was added, and the mixture was stirred at 10,000 rpm for 10 minutes using a high-speed stirrer (Homomixer manufactured by Tokushu Kako Co., Ltd.). The resulting dispersion was opaque and had a particle size measuring device (“N Scientific Co., Ltd.
ICOMP370 "), the particle size of the dispersed phase was measured and found to be 50 nm to 100 µm. Furthermore, the same curing agent, filler, and thickener as in Example 1 were added to this dispersion liquid. Thus, the (meth) acrylic resin composition according to the present invention was obtained.

The obtained (meth) acrylic resin composition was
After aging at 40 ° C for 1 day, the obtained thickened product was cured in the same manner as in Example 1. The volume shrinkage at that time was measured and found to be 4.0%. No pinholes or gloss were found on the surface of the cured product thus obtained, and good surface properties were exhibited. Further, when the cured product was cut into two and its cross section was observed with a scanning electron microscope, many voids with a diameter of about 30 μm were observed in the center of the cured product.

The main results of the above are summarized in Table 4.

[0162]

[Table 4]

[Comparative Example 6] 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 11 was used, and polymethylmethacrylate beads (weight average molecular weight: 950,0) were used.
00) 20 parts was added, and the mixture was stirred for 10 minutes at 10,000 rpm using a high-speed stirrer (Homomixer manufactured by Tokushu Kika Co., Ltd.), and the obtained mixed solution became a transparent solution. The same curing agent, filler, and thickener as in Example 1 were added to this mixed solution. Thereby, a (meth) acrylic resin composition for comparison was obtained.

The obtained (meth) acrylic resin composition for comparison was aged at 40 ° C. for 1 day, and then the obtained thickened product was cured in the same manner as in Example 1. The volumetric shrinkage at that time was measured and found to be 9.5%, and gloss was found on the surface of the obtained cured product. Further, when the thus obtained cured product was cut into two and the cross section thereof was observed by a scanning electron microscope, no void was observed.

The main results of the above are summarized in Table 5.

[Comparative Example 7] 20 parts of polystyrene beads (weight average molecular weight 200,000) were added to 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 11, and a high-speed stirrer (special Using a homomixer manufactured by Kikako Co., Ltd.) and stirring at 10,000 rpm for 10 minutes, the obtained mixed liquid became a transparent solution. In this mixed solution,
The same curing agent, filler, and thickener as in Example 1 were added. Thereby, a (meth) acrylic resin composition for comparison was obtained.

The obtained (meth) acrylic resin composition for comparison was aged at 40 ° C. for 1 day, and then the obtained thickened product was cured in the same manner as in Example 1. The volumetric shrinkage at that time was measured and found to be 9.5%, and gloss was found on the surface of the obtained cured product. Further, when the thus obtained cured product was cut into two and the cross section thereof was observed by a scanning electron microscope, no void was observed.

The main results of the above are summarized in Table 5.

Comparative Example 8 To 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 11, 20 parts of polyvinyl acetate beads (weight average molecular weight 400,000) were added, and a high-speed stirrer was used. After stirring for 10 minutes at 10,000 rpm using (Homo Mixer manufactured by Tokushu Kika Co., Ltd.), the obtained mixed solution became a transparent solution. The same curing agent, filler, and thickener as in Example 1 were added to this mixed solution. Thereby, a (meth) acrylic resin composition for comparison was obtained.

The obtained (meth) acrylic resin composition for comparison was aged at 40 ° C. for 1 day, and then the obtained thickened product was cured in the same manner as in Example 1. The volumetric shrinkage at that time was measured and found to be 9.5%, and gloss was found on the surface of the obtained cured product. Further, when the thus obtained cured product was cut into two and the cross section thereof was observed by a scanning electron microscope, no void was observed.

The main results of the above are summarized in Table 5.

[0172]

[Table 5]

Example 18 In a separable flask equipped with a cooler, a thermometer, a nitrogen gas introducing tube and a stirrer,
After charging 182 parts of t-butyl methacrylate as a (meth) acrylic acid ester and 16 parts of methacrylic acid as a carboxyl group-containing monomer, the flask was purged with nitrogen, and n-dodecyl mercaptan as a chain transfer agent was charged. 17 copies,
Then, 0.03 part of 2,2′-azobisisobutyronitrile as a polymerization initiator was added, and the temperature was raised to 80 ° C. to carry out polymerization. Then, when the solid content concentration of the reaction liquid in the flask reached 50%, 13.2 parts of glycidyl methacrylate as an unsaturated epoxy compound, 0.05 part of benzyltriphenylphosphonium chloride as an esterification catalyst, and as a polymerization inhibitor. Add 0.02 parts of hydroquinone,
After quenching, the temperature was raised to 100 ° C., and the esterification reaction was carried out in an air atmosphere for 15 hours. Thereby, the (meth) acrylic syrup (A) according to the present invention was obtained. The obtained (meth) acrylic syrup (A) has a viscosity at 25 ° C of 25.
Poise, acid value is 20, solid content concentration is 50%, (meta)
The weight average molecular weight of the thermosetting (meth) acrylic polymer in the acrylic syrup (A) was 8,300.

Also, the double bond equivalent of the thermosetting (meth) acrylic polymer in the (meth) acrylic syrup (A) was measured. That is, first, when the acid value of the thermosetting (meth) acrylic polymer in the syrup before and after the reaction with glycidyl methacrylate was measured, the difference was 26.5. From this difference in acid value, the number of moles of the disappeared carboxyl group per 1 g of the thermosetting (meth) acrylic polymer was calculated, and this was calculated as the polymerizable double number in 1 g of the thermosetting (meth) acrylic polymer. The number of moles of bond was used. Then, this value was multiplied by the weight average molecular weight of the thermosetting (meth) acrylic polymer to calculate the double bond equivalent. As a result, in this (meth) acrylic syrup (A), the double bond equivalent was about 2000.

Obtained (meth) acrylic syrup (A)
For 80 parts, cellulose acetate butyrate (“CAB-551-0.01” manufactured by Eastman Chemicals Japan Co., Tg = 40 ° C.) as polymer (B) 20
Parts were added, and the mixture was stirred at 10,000 rpm for 10 minutes using a high-speed stirrer (Homo Mixer manufactured by Tokushu Kako Co., Ltd.). The resulting dispersion was opaque and had a particle size measuring device ("NICOMP37" manufactured by Pacific Scientific Co., Ltd.).
0 ”), the particle size of the dispersed phase was measured to be 100 nm-
It was 500 μm. Furthermore, the same curing agent, filler, and thickener as in Example 1 were added to this dispersion liquid. Thus, the (meth) acrylic resin composition according to the present invention was obtained.

The obtained (meth) acrylic resin composition was
After aging at 40 ° C for 1 day, the obtained thickened product was cured in the same manner as in Example 1. The volume shrinkage at that time was measured and found to be 4.5%. No pinholes or gloss were found on the surface of the cured product thus obtained, and good surface properties were exhibited. Further, when the cured product was cut into two and its cross section was observed with a scanning electron microscope, many voids with a diameter of about 30 μm were observed in the center of the cured product.

The main results of the above are summarized in Table 6.

Example 19 For 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 18,
Ethylene / vinyl acetate copolymer as polymer (B) ("Ultrasen 625" manufactured by Tosoh Corporation, Tg =-
(20 ° C.) 20 parts was added, and the mixture was stirred at 10,000 rpm for 10 minutes using a high-speed stirrer (Homo Mixer manufactured by Tokushu Kako K.K.). The resulting dispersion was opaque and had a particle size measuring device (“NI Scientific Instruments“ NI
The particle size of the dispersed phase was measured by COMP370 ") and found to be 100 nm to 500 µm. Furthermore, the same curing agent, filler, and thickener as in Example 1 were added to this dispersion liquid. Thus, the (meth) acrylic resin composition according to the present invention was obtained.

The obtained (meth) acrylic resin composition was
After aging at 40 ° C for 1 day, the obtained thickened product was cured in the same manner as in Example 1. The volume shrinkage at that time was measured and found to be 4.5%. No pinholes or gloss were found on the surface of the cured product thus obtained, and good surface properties were exhibited. Further, when the cured product was cut into two and its cross section was observed with a scanning electron microscope, many voids with a diameter of about 30 μm were observed in the center of the cured product.

Table 6 shows a summary of the above main results.

Example 20 For 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 18,
Vinyl chloride / vinyl acetate copolymer as the polymer (B) ("Luron TC-806" manufactured by Tosoh Corporation, Tg
(= 60 ° C.) was added, and the mixture was stirred at 10,000 rpm for 10 minutes using a high-speed stirrer (Homo Mixer manufactured by Tokushu Kika Kako Co., Ltd.). The resulting dispersion was opaque and had a particle size measuring device (“NI Scientific Instruments“ NI
The particle size of the dispersed phase was measured by COMP370 ") and was found to be 50 nm to 100 µm. Furthermore, the same curing agent, filler, and thickener as in Example 1 were added to this dispersion liquid. Thus, the (meth) acrylic resin composition according to the present invention was obtained.

The obtained (meth) acrylic resin composition was
After aging at 40 ° C for 1 day, the obtained thickened product was cured in the same manner as in Example 1. The volume shrinkage at that time was measured and found to be 3.5%. No pinholes or gloss were found on the surface of the cured product thus obtained, and good surface properties were exhibited. Further, when the cured product was cut into two and its cross section was observed with a scanning electron microscope, many voids with a diameter of about 30 μm were observed in the center of the cured product.

Table 6 shows a summary of the above main results.

Example 21 For 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 18,
Hydrogenated styrene-butadiene rubber as polymer (B) (“Dyalon 1320 manufactured by Japan Synthetic Rubber Co., Ltd.”
P ”, styrene content 10%, Tg = −50 ° C.) 20 parts, and high-speed stirrer (Homo Mixer manufactured by Tokushu Kako Co., Ltd.)
Was stirred at 10,000 rpm for 10 minutes. The resulting dispersion was opaque and had a particle size measuring device ("NICOMP370" manufactured by Pacific Scientific Co., Ltd.).
Then, the particle size of the dispersed phase was measured and found to be 50 nm to 100 μm.
Met. Furthermore, the same curing agent, filler, and thickener as in Example 1 were added to this dispersion liquid. This allows
A (meth) acrylic resin composition according to the present invention was obtained.

The resulting (meth) acrylic resin composition was
After aging at 40 ° C for 1 day, the obtained thickened product was cured in the same manner as in Example 1. The volume shrinkage at that time was measured and found to be 3.5%. No pinholes or gloss were found on the surface of the cured product thus obtained, and good surface properties were exhibited. Further, when the cured product was cut into two and its cross section was observed with a scanning electron microscope, many voids with a diameter of about 30 μm were observed in the center of the cured product.

Table 6 shows a summary of the above main results.

Example 22 For 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 18,
Maleic anhydride-modified styrene / ethylene / butylene / styrene copolymer as polymer (B) (“Tuftec M1943” manufactured by Asahi Kasei Corporation, styrene content 20%, T
g = -55 ° C.) 20 parts was added, and the mixture was stirred at 10,000 rpm for 10 minutes using a high-speed stirrer (Homo Mixer manufactured by Tokushu Kako Co., Ltd.). The resulting dispersion was opaque and had a particle size measuring device (“N Scientific Co., Ltd.
ICOMP370 "), the particle size of the dispersed phase was measured and found to be 50 nm to 100 µm. Furthermore, the same curing agent, filler, and thickener as in Example 1 were added to this dispersion liquid. Thus, the (meth) acrylic resin composition according to the present invention was obtained.

The obtained (meth) acrylic resin composition was
After aging at 40 ° C for 1 day, the obtained thickened product was cured in the same manner as in Example 1. The volume shrinkage at that time was measured and found to be 4.0%. No pinholes or gloss were found on the surface of the cured product thus obtained, and good surface properties were exhibited. Further, when the cured product was cut into two and its cross section was observed with a scanning electron microscope, many voids with a diameter of about 30 μm were observed in the center of the cured product.

Table 6 shows a summary of the above main results.

Example 23 To 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 18,
Styrene-butadiene rubber as polymer (B) (“Niponol NS-112” manufactured by Nippon Zeon Co., Ltd., T
(g = -68 ° C.) (20 parts) was added, and the mixture was stirred at 10,000 rpm for 10 minutes using a high-speed stirrer (Homo Mixer manufactured by Tokushu Kako Co., Ltd.). The resulting dispersion was opaque and had a particle size measuring device (“N Scientific Co., Ltd.
ICOMP370 "), the particle size of the dispersed phase was measured and found to be 50 nm to 100 µm. Furthermore, the same curing agent, filler, and thickener as in Example 1 were added to this dispersion liquid. Thus, the (meth) acrylic resin composition according to the present invention was obtained.

The resulting (meth) acrylic resin composition was
After aging at 40 ° C for 1 day, the obtained thickened product was cured in the same manner as in Example 1. The volume shrinkage at that time was measured and found to be 4.0%. No pinholes or gloss were found on the surface of the cured product thus obtained, and good surface properties were exhibited. Further, when the cured product was cut into two and its cross section was observed with a scanning electron microscope, many voids with a diameter of about 30 μm were observed in the center of the cured product.

The main results of the above are summarized in Table 6.

Example 24 For 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 18,
Nitrile-butadiene rubber as polymer (B) (“Niponol DN214” manufactured by Nippon Zeon Co., Ltd., Tg
(= -22 ° C) was added, and the mixture was stirred at 10,000 rpm for 10 minutes using a high-speed stirrer (Homo Mixer manufactured by Tokushu Kika Kako Co., Ltd.). The resulting dispersion was opaque and had a particle size measuring device (“NI Scientific Instruments“ NI
The particle size of the dispersed phase was measured by COMP370 ") and was found to be 50 nm to 100 µm. Furthermore, the same curing agent, filler, and thickener as in Example 1 were added to this dispersion liquid. Thus, the (meth) acrylic resin composition according to the present invention was obtained.

The obtained (meth) acrylic resin composition was
After aging at 40 ° C for 1 day, the obtained thickened product was cured in the same manner as in Example 1. The volume shrinkage at that time was measured and found to be 4.0%. No pinholes or gloss were found on the surface of the cured product thus obtained, and good surface properties were exhibited. Further, when the cured product was cut into two and its cross section was observed with a scanning electron microscope, many voids with a diameter of about 30 μm were observed in the center of the cured product.

Table 6 shows a summary of the above main results.

Example 25 With respect to 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 18,
Styrene / ethylene / propylene / styrene copolymer as the polymer (B) (“Septon 20 manufactured by Kuraray Co., Ltd.
63 ", styrene content 13%, Tg = -50 ° C) 20 parts, and 4 parts of styrene-vinyl acetate copolymer (NOF Corporation" MODIPA S-501 ") as a dispersion stabilizer were added, The mixture was stirred at 10,000 rpm for 10 minutes using a high-speed stirrer (Homo Mixer manufactured by Tokushu Kika Co., Ltd.). The resulting dispersion was opaque and had a particle size measuring device ("NICOMP37" manufactured by Pacific Scientific Co., Ltd.).
0 ”), the particle size of the dispersed phase was measured and found to be 50 nm to 1
It was 00 μm. Furthermore, the same curing agent, filler, and thickener as in Example 1 were added to this dispersion liquid. Thus, the (meth) acrylic resin composition according to the present invention was obtained.

The obtained (meth) acrylic resin composition was
After aging at 40 ° C for 1 day, the obtained thickened product was cured in the same manner as in Example 1. The volume shrinkage at that time was measured and found to be 3.5%. No pinholes or gloss were found on the surface of the cured product thus obtained, and good surface properties were exhibited. Further, when the cured product was cut into two and its cross section was observed with a scanning electron microscope, many voids with a diameter of about 30 μm were observed in the center of the cured product.

Table 6 shows a summary of the above main results.

[0199]

[Table 6]

Comparative Example 9 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 18 was used and beads of polymethylmethacrylate (weight average molecular weight of 950,0).
00) 20 parts was added, and the mixture was stirred for 10 minutes at 10,000 rpm using a high-speed stirrer (Homomixer manufactured by Tokushu Kika Co., Ltd.), and the obtained mixed solution became a transparent solution. The same curing agent, filler, and thickener as in Example 1 were added to this mixed solution. Thereby, a (meth) acrylic resin composition for comparison was obtained.

The obtained (meth) acrylic resin composition for comparison was aged at 40 ° C. for 1 day, and then the obtained thickened product was cured in the same manner as in Example 1. The volumetric shrinkage at that time was measured and found to be 9.5%, and gloss was found on the surface of the obtained cured product. Further, when the thus obtained cured product was cut into two and the cross section thereof was observed by a scanning electron microscope, no void was observed.

The main results of the above are summarized in Table 7.

Comparative Example 10 With respect to 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 18,
20 parts of polystyrene beads (weight average molecular weight 200,000) were added, and the mixture was stirred at 10,000 rpm for 10 minutes using a high-speed stirrer (Homo Mixer manufactured by Tokushu Kako Co., Ltd.), and the resulting mixed solution became a transparent solution. It was The same curing agent, filler, and thickener as in Example 1 were added to this mixed solution. Thereby, a (meth) acrylic resin composition for comparison was obtained.

The obtained (meth) acrylic resin composition for comparison was aged at 40 ° C. for 1 day, and then the obtained thickened product was cured in the same manner as in Example 1. The volumetric shrinkage at that time was measured and found to be 9.5%, and gloss was found on the surface of the obtained cured product. Further, when the thus obtained cured product was cut into two and the cross section thereof was observed by a scanning electron microscope, no void was observed.

Table 7 shows a summary of the above main results.

[Comparative Example 11] With respect to 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 18,
20 parts of polyvinyl acetate beads (weight average molecular weight 40,000) was added, and the mixture was stirred at 10,000 rpm for 10 minutes using a high-speed stirrer (Homo Mixer manufactured by Tokushu Kako Co., Ltd.), and the resulting mixture was a transparent solution. Became. The same curing agent, filler, and thickener as in Example 1 were added to this mixed solution. Thereby, a (meth) acrylic resin composition for comparison was obtained.

The obtained (meth) acrylic resin composition for comparison was aged at 40 ° C. for 1 day, and then the obtained thickened product was cured in the same manner as in Example 1. The volumetric shrinkage at that time was measured and found to be 9.5%, and gloss was found on the surface of the obtained cured product. Further, when the thus obtained cured product was cut into two and the cross section thereof was observed by a scanning electron microscope, no void was observed.

The main results of the above are summarized in Table 7.

[0209]

[Table 7]

[Example 26] 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 1 was added to styrene / ethylene / propylene / polymer (B).
Styrene copolymer (Kuraray Co., Ltd. “Septon 200
5 ", styrene content 20%, Tg = -53 ° C) 20 parts, added, high speed stirrer (Homo Mixer manufactured by Tokushu Kika Co., Ltd.)
Was stirred at 10,000 rpm for 10 minutes. The resulting dispersion was opaque and had a particle size measuring device ("NICOMP370" manufactured by Pacific Scientific Co., Ltd.).
Then, the particle size of the dispersed phase was measured and found to be 50 nm to 100 μm.
Met. Furthermore, 1,1-bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane as a curing agent was added to this dispersion (“Perhexa TMH” manufactured by NOF Corporation, 10
Time half-life temperature 86.7 ° C) 1 part, aluminum hydroxide as filler (Showa Denko KK "Hijilite H-3"
20 ") 100 parts, magnesium oxide 1.67 as thickener
Parts and 4 parts of zinc stearate as a release agent were mixed to obtain a compound.

Then, the compound was applied to the surface of the polyethylene film so as to have a constant thickness, and glass fibers (chopped strands having a length of 1 inch) as a reinforcing material were evenly spread on the applied material. did. Then, a coating material obtained by applying the compound to the surface of the polyethylene film so as to have a constant thickness was superimposed thereon. That is, the glass fiber was sandwiched between the compounds. Thereby, SMC as a (meth) acrylic resin composition was obtained. The ratio of the glass fiber in the SMC was adjusted to be 25%. After that, the obtained S
MCs were wrapped in cellophane film and aged at 40 ° C for 1 day.

Next, the above SMC was heated and pressed.
That is, a mold having a size of 300 mm × 300 mm was used, the temperature of the upper mold was set to 110 ° C., and the temperature of the lower mold was set to 100 ° C. And SMC cut into 150mm x 150mm size
Was filled in the above mold, clamped at a pressure of 6 MPa, and heated and pressed for 10 minutes to give a molded product having a thickness of 3
A mm shaped plate was created.

The molded plate thus obtained had good surface properties without pinholes or gloss unevenness on both front and back surfaces. The main results of the above are summarized in Table 8.

[Example 27] 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 1 was added to styrene / ethylene / propylene / polymer as the polymer (B).
Styrene copolymer (Kuraray Co., Ltd. “Septon 200
5 ", styrene content 20%, Tg = -53 ° C) 20 parts, added, high speed stirrer (Homo Mixer manufactured by Tokushu Kika Co., Ltd.)
Was stirred at 10,000 rpm for 10 minutes. The resulting dispersion was opaque and had a particle size measuring device ("NICOMP370" manufactured by Pacific Scientific Co., Ltd.).
Then, the particle size of the dispersed phase was measured and found to be 50 nm to 100 μm.
Met.

Furthermore, 1,1-
Bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane ("Perhexa TMH" manufactured by NOF CORPORATION,
10 hours 10 minutes half-life temperature 86.7 ° C) 1 part, aluminum hydroxide as a filler (Showa Denko KK "Hijilite H-
320 ") 350 parts, magnesium oxide as thickener 1.
67 parts, 4 parts of zinc stearate as a release agent, and glass fiber (1/4 inch in length chopped strands) as a reinforcing material were mixed, and then this mixture was kneaded using a double-arm kneader. did. Thus, BMC as a (meth) acrylic resin composition was obtained. The proportion of the glass fiber in the BMC was adjusted to be 5%. Thereafter, the obtained BMC was wrapped with a vinylon film and aged at 40 ° C. for 1 day.

Next, the above BMC was heated and pressed.
That is, a mold having a size of 300 mm × 300 mm was used, the temperature of the upper mold was set to 110 ° C., and the temperature of the lower mold was set to 100 ° C. Then, the above-mentioned BMC is filled in the above-mentioned mold, and the pressure 6
A mold plate having a thickness of 3 mm, which is a molded product, was prepared by clamping the mold with MPa and heating and pressing for 10 minutes.

The molded plate thus obtained had good surface properties without pinholes or gloss unevenness on both front and back surfaces. The main results of the above are summarized in Table 8.

Example 28 First, 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 1 was subjected to the same operation as in Example 26 to obtain a compound.

Next, the compound was poured into a resin tank, glass fibers (glass roving and continuous mat) as a reinforcing material were set, and a mold temperature of 80
Pultrusion molding was performed at a temperature of 30 ° C. and a drawing speed of 30 cm / min. The glass fiber was set so that the glass roving was the core and the continuous mat was the surface. The glass fiber content was adjusted to 60%. Thereby, a flat plate molded product was obtained.

The molded plate thus obtained had good surface properties without pinholes or gloss unevenness on both front and back surfaces. The main results of the above are summarized in Table 8.

Example 29 First, with respect to 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 1, the same operation as in Example 27 was carried out to obtain a (meth) acrylic resin composition. BMC as a product was obtained. Thereafter, the obtained BMC was wrapped with a vinylon film and aged at 40 ° C. for 1 day.

Next, the above BMC was injection molded. That is, a mold having a size of 100 mm × 200 mm × 3 mm was used and the mold temperature was set to 110 ° C. Then, the BMC was filled in the mold with a plunger, clamped at a pressure of 6 MPa, and heated and pressed for 10 minutes to form a molded plate having a thickness of 3 mm.

The molded plate thus obtained had good surface properties without pinholes or gloss unevenness on both front and back surfaces. The main results of the above are summarized in Table 8.

Example 30 First, 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 1 was subjected to the same operation as in Example 26 to obtain a compound.

Next, the compound was poured into a resin tank of a resin transfer molding machine, and a glass mat as a reinforcing material was added.
The resin was set in a mold having a size of 00 mm × 300 mm × 3 mm, and the resin was transferred and molded at a mold temperature of 80 ° C for 1 hour. The glass fiber content was adjusted to 30%. As a result, a molded plate having a thickness of 3 mm, which is a molded product, was obtained.

The obtained molded plate had good surface properties without pinholes or gloss unevenness on both front and back surfaces. The main results of the above are summarized in Table 8.

[0227]

[Table 8]

[Comparative Example 12] 80 parts of the comparative (meth) acrylic syrup (A) synthesized in the same manner as in Comparative Example 1 was subjected to the same operation as in Example 26 to obtain a comparative SMC.
I got Then, the obtained comparative SMC was wrapped with a cellophane film and aged at 40 ° C. for 1 day.

Next, the above-mentioned SMC for comparison was used in Example 2.
By heating and pressurizing in the same manner as 6, the thickness is 3 mm.
A molded plate for comparison was prepared.

A lot of gloss unevenness was generated on the surface of the obtained molded plate for comparison. The main results of the above are summarized in Table 9.

Comparative Example 13 Example 26 was repeated except that the styrene / ethylene / propylene / styrene copolymer was not used for 80 parts of the (meth) acrylic syrup (A) synthesized in the same manner as in Example 1. A similar operation was performed to obtain a SMC for comparison. After that, the obtained SMC for comparison was
It was wrapped with cellophane film and aged at 40 ° C. for 1 day. Next, the comparative SMC was heat-pressed in the same manner as in Example 26 to prepare a comparative molded plate having a thickness of 3 mm.

In the obtained molded plate for comparison, a lot of gloss unevenness was generated on the lower (low temperature side) surface of the mold, and a good molded product could not be obtained. The main results of the above are summarized in Table 9.

Comparative Example 14 Example 27 was repeated except that the styrene / ethylene / propylene / styrene copolymer was not used for 80 parts of the (meth) acrylic syrup (A) synthesized in the same manner as in Example 1. The same operation as above was performed to obtain a BMC for comparison. After that, the obtained BMC for comparison was
It was wrapped with a vinylon film and aged at 40 ° C for 1 day.
Next, the comparative BMC was heat-pressed in the same manner as in Example 27 to prepare a comparative molded plate having a thickness of 3 mm.

In the obtained molded plate for comparison, a lot of gloss unevenness was generated on the lower (low temperature side) surface of the mold, and a good molded product could not be obtained. The main results of the above are summarized in Table 9.

[Comparative Example 15] 80 parts of (meth) acrylic syrup (A) synthesized in the same manner as in Example 1 was replaced with beads of polymethyl methacrylate instead of the styrene-ethylene-propylene-styrene copolymer. The same operation as in Example 27 was carried out except using (weight average molecular weight 950,000) to obtain a BMC for comparison. Then, the obtained BMC for comparison was wrapped in a vinylon film and aged at 40 ° C. for 1 day. Next, the above-mentioned BMC for comparison was heated and pressed in the same manner as in Example 27 to give a thickness of 3
A mm shaped comparative plate was made.

In the obtained molded plate for comparison, a lot of gloss unevenness was generated on the lower (low temperature side) surface of the mold, and a good molded product could not be obtained. The main results of the above are summarized in Table 9.

Comparative Example 16 Example 28 was repeated except that the styrene / ethylene / propylene / styrene copolymer was not used for 80 parts of the (meth) acrylic syrup (A) synthesized in the same manner as in Example 1. The same operation was carried out to obtain a compound for comparison. Next, the comparative compound was subjected to pultrusion molding in the same manner as in Example 28 to prepare a comparative molded plate having a thickness of 3 mm.

The surface of the comparative molded plate thus obtained had a shark skin, and a good molded product could not be obtained. The main results of the above are summarized in Table 9.

Comparative Example 17 Example 27 was repeated except that the styrene / ethylene / propylene / styrene copolymer was not used for 80 parts of the (meth) acrylic syrup (A) synthesized in the same manner as in Example 1. The same operation as above was performed to obtain a BMC for comparison. After that, the obtained BMC for comparison was
It was wrapped with a vinylon film and aged at 40 ° C for 1 day.
Next, the comparative BMC was injection-molded in the same manner as in Example 29 to prepare a comparative molded plate having a thickness of 3 mm.

On the obtained molded plate for comparison, a lot of gloss unevenness was generated and a good molded product could not be obtained. The main results of the above are summarized in Table 9.

Comparative Example 18 Example 28 was repeated except that the styrene / ethylene / propylene / styrene copolymer was not used for 80 parts of the (meth) acrylic syrup (A) synthesized in the same manner as in Example 1. The same operation was carried out to obtain a compound for comparison. Next, the comparative compound was subjected to resin transfer molding in the same manner as in Example 30 to prepare a comparative molded plate having a thickness of 3 mm.

On the obtained molded plate for comparison, a lot of gloss unevenness occurred, and a good molded product could not be obtained. The main results of the above are summarized in Table 9.

[0243]

[Table 9]

As is clear from Tables 1 to 9, the (meth) acrylic resin composition according to this example has a low volume shrinkage ratio upon curing. Further, it can be seen that the cured product obtained by curing the (meth) acrylic resin composition according to the present example has no pinholes or gloss unevenness and is excellent in surface smoothness and surface properties such as gloss.

[0245]

EFFECT OF THE INVENTION According to the (meth) acrylic resin composition of the present invention, it is possible to obtain a cured product having a low volume shrinkage ratio upon curing and excellent surface smoothness and surface properties such as gloss. Play.

Further, according to the method for producing a (meth) acrylic resin composition of the present invention, it is possible to produce a (meth) acrylic resin composition having a low volume shrinkage ratio upon curing,
By curing the (meth) acrylic resin composition, it is possible to obtain a cured product having excellent surface properties such as surface smoothness and gloss.

Claims (3)

[Claims] 1. A (meth) acrylic syrup (A) composed of a thermosetting (meth) acrylic polymer and a vinyl monomer, and at least one selected from the group consisting of a thermoplastic resin, a thermoplastic elastomer and a rubber. A (meth) acrylic resin composition containing one type of polymer (B), wherein the polymer (B) is dispersed in the (meth) acrylic syrup (A). 2. The (meth) acrylic resin composition according to claim 1, wherein the polymer (B) is a styrene thermoplastic elastomer. 3. A (meth) acrylic syrup (A) comprising a thermosetting (meth) acrylic polymer and a vinyl monomer.
And at least one polymer (B) selected from the group consisting of thermoplastic resin, thermoplastic elastomer, and rubber
A method for producing a (meth) acrylic resin composition, comprising: