JPS62220508A - Methacrylate resin having excellent heat-resistance and impact-resistance - Google Patents

Abstract

PURPOSE:To obtain a methacrylate resin having excellent heat-resistance and impact-resistance while keeping various characteristics of original resin such as optical properties, weather resistance, hardness, etc., by polymerizing a polymerizable syrup composed of a reactive elastomer, an aromatic vinyl monomer, maleic anhydride, etc. CONSTITUTION:The objective resin can be produced by polymerizing a polymerizable syrup composed of (A) 0.5-50(wt)% reactive elastomer (e.g. carboxyl-modified polybutadiene), (B) 1-50% aromatic vinyl monomer (e.g. styrene, isoprophenylstyrene, etc.), (C) 1-25% maleic anhydride, (D) 40-97.5% methyl methacrylate and (E) 0-40% other monomer copolymerizable with the above monomers (e.g. methyl acrylate, N-cyclohexyl maleimide, etc.) (the sum of the components A-E is 100%).

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a methacrylic resin with excellent heat resistance and impact resistance, and more specifically to a reactive elastomer, an aromatic vinyl monomer, maleic anhydride, and methacrylic acid. This invention relates to a methacrylic resin obtained by polymerizing a polymerizable syrup consisting of methyl and other monomers copolymerizable with these.

<Prior art and problems to be solved by the invention> Generally, methacrylic resin is used for signboards, glazing materials, interiors, automobile parts, electrical equipment parts, etc. due to its excellent optical properties, weather resistance, hardness, etc. Widely used in various products.

However, on the other hand, it has a serious drawback in that its heat resistance and WJ impact resistance are not necessarily sufficient.

If the impact resistance of methacrylic resin is improved, it will be possible to reduce the inconvenience of handling methacrylic resin products during transportation and various processing, and it will also be possible to make the products thinner. That is, those skilled in the art are eager to reduce raw material costs, transportation costs, etc. by reducing the weight of products. Furthermore, with regard to heat resistance, there are persistent demands for improvement in fields where shape stability at high temperatures is required.

Many proposals have been made so far as methods for obtaining methacrylic resins with excellent heat resistance or impact resistance. For example, to improve heat resistance, a method of copolymerizing methyl methacrylate and N-arylmaleimide (
Special Publication No. 43-9753), methyl methacrylate, α-
A method of blending a copolymer of methyl styrene and maleic anhydride with a methyl methacrylate polymer (Japanese Patent Laid-Open No. 5
9-122536), and for improving impact resistance, there is a method of polymerizing methyl methacrylate and an acrylic acid alkyl ester to form a soft polymer in multiple stages (Japanese Patent Laid-Open No. 59-202213). However, these methods have the problem that mechanical properties such as impact resistance deteriorate if heat resistance is not improved, and heat resistance decreases if impact resistance is not improved. No material has been found that combines strength and impact resistance. In addition, as a method for obtaining a methacrylic resin that has both heat resistance and impact resistance, a copolymer consisting of methyl methacrylate, an aromatic vinyl monomer, and maleic anhydride, a monomer that gives a hard polymer, and a soft polymer A method of blending a graft copolymer obtained by multi-step polymerization of monomers that provide coalescence (
JP 60-60150, JP 60-63247, JP 60-63248, JP 171111 [60-
No. 69151, JP-A No. 69-69152, JP-A No. 69-Sho 60
-69153, JP-A No. 60-69154), a terpolymer consisting of α-methylstyrene, methyl methacrylate, and acrylonitrile is added to a graft copolymer obtained by graft copolymerizing styrene or acrylonitrile to a diene rubber. How to blend (Special Hrli57 7014
No. 3) and the like have been disclosed, but the reality is that heat resistance and impact resistance must be balanced at low levels because they require flow processability as a thermoplastic resin.

<Means and effects for solving problem 1> In view of these circumstances, the present inventors have developed a method for improving heat resistance without reducing the excellent optical properties, weather resistance, hardness, and other properties of methacrylic resin. As a result of intensive research to obtain a methacrylic resin with excellent properties and impact resistance, we developed a polymerizable syrup containing a reactive elastomer, aromatic liquid vinyl monomer, maleic anhydride, and methyl methacrylate in specific ranges. The present invention was completed by discovering that the intended purpose could be fully achieved by polymerization.

That is, in the present invention, reactive elastomer (A) 0.5 to
50% by weight, aromatic vinyl monomer (B) 1 to 50% by weight
, maleic anhydride &1 (C) 1 to 25% by weight, methyl methacrylate (D) 40 to 97.5% by weight, and other monomers copolymerizable with these (E) 0 to 40% by weight (however,
(A), (B), (C).

The sum of components (D) and (E) is 100%. )
This invention relates to a methacrylic resin with excellent heat resistance and impact resistance obtained by polymerizing a polymerizable syrup consisting of:

As used herein, the term "reactive elastomer" refers to a "reactive elastomer that can cause or participate in a so-called radical reaction" under the action of heat, ultraviolet light, electron beams, free radical generating agents, etc. Refers to an elastomer having an unsaturated group in its side chain. Generally, an elastomer is mixed into a composition containing a monomer as a means of imparting W impact resistance to a cured polymer obtained from the composition. However, in such cases, although the impact resistance of the cured polymer is improved, it often results in a decrease in transparency and surface hardness, and further a significant decrease in heat resistance.

The significance of using the reactive elastomer (A) in the present invention is to eliminate the above-mentioned disadvantages.

That is, in the polymerizable syrup used in the present invention, the reactive elastomer (A) in the syrup is converted into aromatic vinyl monomer (B), maleic anhydride M (C), and 1-methyl methacrylate ([) during the polymerization and curing process. ) to form a cured matrix in which the two are integrated, methacrylic resin has improved impact resistance and heat resistance while maintaining transparency and surface hardness. can give.

Several proposals have been made as a method for obtaining a reactive elastomer (A) by introducing a reactive unsaturated group into an elastomer.

The first method utilizes an esterification reaction, for example, the reaction of an elastomer containing a free carboxyl group with an unsaturated hydroxy compound or an unsaturated glycidyl compound, or the reaction of an elastomer containing a hydroxyl group or a glycidyl group with an unsaturated glycidyl compound. It is a reactive elastomer obtained by a method utilizing a reaction with a saturated carboxylic acid compound.

Examples of reactive elastomers obtained by this method include elastomers obtained by copolymerizing allyl alcohol with droxyethyl acrylate, hydroxyethyl methacrylate, glycidyl methacrylate, etc., and acrylic acid, methacrylic acid, crotonic acid, vinyl benzoic acid, etc. There are reactants with acids, unsaturated basic acids such as cinnamic acid, etc. Conversely, an elastomer obtained by copolymerizing the unsaturated basic acid or an unsaturated dibasic acid such as maleic acid, fumaric acid, itaconic acid, etc. or maleic anhydride, or its acid anhydride, and allyl alcohol, hydroxyethyl Reactants with unsaturated hydroxy compounds such as acrylate and hydroxyethyl methacrylate, and unsaturated glycidyl compounds such as glycidyl methacrylate are also examples that can be used in the present invention. Among these, the industrially advantageous ones utilize the reaction between hydroxyl groups and glycidyl groups.

In this case, as a means to reduce the danger of 01 reaction light such as the polymerization reaction of unsaturated groups during the reaction, a polymerization inhibitor such as hydroquinone, methoquinone, or dopanol (r (manufactured by 1 company)) may be added to the reaction system. Measures such as introducing an acid and relaxing reaction conditions by using an esterification catalyst such as amines can be applied.

The second method is a method that utilizes a urethane reaction, in which the hydroxyl groups in the elastomer copolymerized with the unsaturated hydroxy compound and the hydroxyl groups of the unsaturated hydroxy compound are combined with the respective isocyanate groups in the diisocyanate compound to form a urethane reaction. It is obtained by bonding through a reaction and adding an unsaturated group to the elastomer.

As the diisocyanate compound, toluene diisocyanate, 4,4'-diphenylmethane diisocyanate, naphthalene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, etc. can be used. This unsaturated group addition reaction uses a well-known organotin compound as a catalyst. In addition, in order to react with good selectivity the hydroxyl group in the elastomer and the unsaturation, the hydroxyl group of the droxy compound, and the isocyanate group of one side of the diisocyanate compound and the isocyanate group of the other side, the reactions are carried out sequentially. It is preferable. In this case as well, it is preferable to add the above-mentioned polymerization inhibitor. Further, when this reaction is utilized, an unsaturated hydroxy compound can be reacted with an elastomer into which isocyanate groups have been introduced.

The third method involves the reaction of an elastomer containing a free carboxyl group with an unsaturated aziridine compound (a) having one aziridine group and at least one radically reactive unsaturated group in one molecule. It uses This third method is a preferred embodiment of the present invention. The unsaturated aziridine compound (a) used in this method is divided into unsaturated basic aziridine compounds and unsaturated active aziridine compounds depending on the characteristics of the aziridine group. An unsaturated basic aziridine compound is a compound in which the nitrogen atom of the aziridine group in the molecule exhibits basicity. ~4 alkyl group, R5 represents hydrogen or a methyl group).

On the other hand, an unsaturated active aziridine compound is a compound in which the nitrogen atom of the aziridine group in the molecule does not exhibit basicity.
5 is the same as above. ) can be mentioned.

The reason for classifying the unsaturated aziridine compound (a) as described above is as follows.

In the present invention, the reaction between the free carboxyl group in the elastomer and the aziridine group in the unsaturated aziridine compound (a) proceeds by an esterification reaction. When an unsaturated basic aziridine compound is used in this esterification reaction, in the reaction, the carboxyl group and the aziridine group once form a salt, and as the esterification reaction progresses, a basic amino group is formed, and the reaction occurs outside the system. Unless acid is added from
This basic amino group forms a salt with other carboxyl groups in the elastomer, and the esterification reaction does not proceed ((), and the esterification reaction remains at about 50% of its theoretical value. In the case of an aziridine compound, no basic amine groups are generated, and theoretically all m of carboxyl groups in the elastomer can be reacted.

The unsaturated aziridine compound (a) that can be used in the present invention is illustrated below. Representative unsaturated basic aziridine compounds are as follows.

CH20-Go-CH-CH2 CH20-Co-C(CH3)=CH2CH20-Co
-C(CH3)=CH2 Representative unsaturated active aziridine compounds are as follows.

CH2=CH+5O2-N.

CH2-C(CH3)-C)-802-N (CH2=
CH-CΣNHCO-NgCH2-C(CH3)+NHCO-NgCH2=CH-
C0NH Tsuhe 2-NgCH2-C(CH3)-CONH(ySO2-N off CH
2-CH-Coo-CH2CH2-Nhco-Nq In the present invention, when an unsaturated basic aziridine compound is used, as the esterification reaction progresses, a basic amino group is generated and the esterification reaction progresses. This sometimes becomes a drawback.The present inventors also provide a method for improving such a drawback.

That is, when reacting an elastomer containing a free carboxyl group with an unsaturated basic aziridine compound, at least one kind selected from the group consisting of monoisocyanate compounds, monothioisocyanate compounds, ketene compounds, and ketene dimers is used. This objective can be achieved by using compound (b) in combination. Compound (0
) quickly reacts with the basic amino group produced by the esterification reaction and has the effect of reducing its basicity. The compound (b) includes monoisocyanates R6-NGO, monothioisocyanates R6-NC
8, Ketenes C-C-0 and ketene dimers R7' -C-O (wherein, R6 has 1 to 12 carbon atoms, preferably 1 to 8 carbon atoms)
an alkyl group, a cycloalkyl group, an aryl group,
Further, R7 and R7' are hydrogen, an alkyl group having 1 to 8 carbon atoms, preferably 1 to 6 carbon atoms, a cycloalkyl group, an aryl group, and an aryl group. ), preferably monoisocyanates and ketenes.

Examples of typical compounds (b) include methyl isocyanate, ethyl isocyanate, propyl isocyanate, phenyl isocyanate, ketene, and ketene dimer.

In the third method for obtaining the reactive elastomer (A) used in the present invention, generally 0.05 to 1.2 of the unsaturated aziridine compound (A) is added to 1.0 mol of free carboxyl groups in the elastomer. React in proportions in the molar range. In a preferred embodiment of the present invention, when an unsaturated basic aziridine compound is used, the amount is 0.1 to 0.5 mol per 1.0 mol of free carboxyl groups in the elastomer, and an unsaturated active aziridine compound is used. When the unsaturated basic aziridine compound and the compound (b) are used in combination, the amount is 0.1 to 1.0 mol.
The amount of the unsaturated basic aziridine compound is 0.1 to 1.0 mol, and the ratio of compound (b) to 1.0 mol of the unsaturated basic aziridine compound is 0.8 to 1.2 mol. The temperature of this reaction is preferably 40 to 130°C, although it proceeds at room temperature.

Elastomers containing free carboxyl groups can be obtained using conventionally well-known reactions.

Such elastomers include monomers that provide elastomeric properties, such as acrylic acid, methacrylic acid,
Elastomer obtained by copolymerizing one or more free carboxyl group-containing polymerizable monomers such as crotonic acid, itaconic acid, maleic acid, fumaric acid, etc. according to a conventionally known method; Polymers containing free carboxyl groups by hydrolyzing homopolymers or copolymers obtained by polymerizing saturated monomers by conventionally known methods: Known polymerization initiators and chains containing free carboxyl groups. Examples include polymers containing free carboxyl groups using transfer agents, polymerization terminators, and the like.

In addition, the main structural unit of the elastomer capable of expressing its elastomeric properties is a known monomer having a relatively low glass transition point, such as ethylene, butadiene, ethyl, butyl, or 2-ethylhexyl ester of acrylate. They are monomers. In addition, other known monomers may be copolymerized with the monomer giving the elastomer properties and the unsaturated monomer containing a free carboxyl group, as long as the elastomer properties are not lost.

Specific examples of these free carboxyl group-containing elastomers include carboxy-modified polybutadiene, carboxy-modified butadiene elastomers such as SBR or NOR, ethyl acrylate-(meth)acrylic acid copolymer, butyl acrylate- Examples include carboxy-modified acrylic elastomers such as (meth)acrylic acid copolymers and 2-ethylhexyl acrylate-(meth)acrylic acid copolymers.

Ta of the reactive elastomer (A) must be 20°C or less. If Tg is higher than 20°C, the [111] resistance of the resulting methacrylic resin will not be improved. More preferably, To is 0°C or lower. Tg may be measured in practice, or as described by Fox, Bull, AtPhysi.
cs Soc,” Vol. 1. No.

3, P123 (1956).

Further, the number average molecular weight of the elastomer (A) is 10,
Preferably, the value is OO0 or more. Number average molecular weight is 10.
If less than OO0 is used, it is difficult to improve the impact resistance of the methacrylic resin. More preferably, the number average molecular weight is 40. It is OO0 or more. The upper limit of the amount of Hideko is not particularly limited, but considering solubility in other components in the polymerizable syrup, workability, etc., the upper limit is 1,000,000.

The concentration of unsaturated groups in the elastomer (A) is 0.01 to 5.
milliequivalent/g. If it is less than o, oi per milliliter/g, the unsaturated group concentration will not reach a substantially effective amount, and the resulting methacrylic resin will have substantially no hardened graft formation and will have low impact resistance and transparency. becomes. In addition, when a methacrylic resin having a concentration exceeding 5 millimeters of ffi/g is used, the resulting methacrylic resin will only be hard and brittle, although sufficient transparency can be obtained. Therefore, the concentration of unsaturated groups in the elastomer (A) is 0.01 to 5 milliequivalents/
g, more preferably 0.05 to 2 mm/g
The range is 1/Q.

The amount of reactive engineered elastomer (A) used by blending into the polymerizable syrup is 0.5 to 50% by weight in the polymerizable syrup.
This is the ratio of The elastomer (A) in polymerizable syrup
If the amount is less than 0.5117%, it is not a substantially effective amount, and the resulting methacrylic resin will not have improved impact resistance.

In addition, if the amount of the elastomer (A) exceeds 50% by weight, the viscosity of the polymerizable syrup becomes high, making blending and cast polymerization difficult, and the resulting methacrylic resin is also soft and has poor surface hardness and heat resistance. becomes. The elastomer (
A> is more preferably used in a range of 5 to 30%.

The aromatic vinyl monomer (B) and maleic anhydride (C) used in the present invention are components mainly for imparting heat resistance and hardness, such as improving thermal decomposition temperature and heat distortion temperature.

Examples of the aromatic vinyl monomer (B) include styrene, α-methylstyrene, paramethylstyrene, isopropenylstyrene, chlorstyrene, etc., and one or more of these can be used. . In the polymerizable syrup, the aromatic vinyl monohedron (B) is used in a proportion of 1 to 50% by weight, and the maleic anhydride (C) is used in a proportion of 1 to 25% by weight. If the amount of aromatic vinyl monomer (B) or maleic anhydride (C) used is less than 1%, it will not be possible to impart sufficient heat resistance and hardness to the resulting resin, and the aromatic vinyl When the amount of monomer (B) used is more than 50% by weight and when the amount of anhydrous maleic 1 (C) used is more than 25% by weight, the impact resistance of the resulting resin decreases, which is not preferable.

Methyl methacrylate (D) used in the present invention is used in a proportion of 40 to 97.5 ffl% by weight, preferably 50 to 85% by weight in the polymerizable syrup. Use Φ
If the amount is less than 40% by weight, the resulting resin will not be able to maintain the optical properties, weather resistance, and mechanical properties inherent to the methacrylic resin, and if the amount is more than 97.51%, the resulting resin will not retain the original optical properties, weather resistance, and mechanical properties. Both are unfavorable because heat resistance and impact resistance decrease.

Examples of the monomer (E) used as necessary in the present invention include methyl acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, cyclohexyl (meth)acrylate, vinyl acetate, Ethylene glycol di(
meth)acrylate, trimethylolpropane tri(meth)acrylate, maleimide, N-methylmaleimide.

Examples include N-phenylmaleimide and N-cyclohexyl'maleimide.

The monomer (E) contains 0 to 40% by weight of t in the polymerizable syrup.
! It may be used in a surrounding area, but the amount used is 40% by weight.
If the amount is too large, the resulting resin will have poor weather resistance, heat resistance, and resistance to 17
This is not preferable because the balance of s properties, etc. (shifting) causes performance to deteriorate.

In the present invention, curing agents used to polymerize the polymerizable syrup include azo compounds and organic peroxides as polymerization initiators. Azo compounds include 2.2'-azobisisobutyonitrile, 2.2'-azobis-2
, 4-dimethylvaleronitrile, 1-azobis-1-cyclohexanecarbonitrile and dimethyl-2,2'
-Azobisisobutyrate and the like.

Examples of the organic peroxide include benzoyl peroxide, methyl ethyl ketone peroxide, methyl isobutyl ketone peroxide, cumyl hydroperoxide, and cyclohexanone peroxide. It is also possible to use a combination of an organic peroxide and an accelerator for curing at low temperatures.

Tertiary amines and quaternary ammonium salts are used as accelerators.

Examples include soluble gold B salts such as cobalt, manganese, iron, copper, and calcium.

The ratio of curing agent to polymerizable syrup is usually 0, OO
1 to 2% by weight, and if necessary, an accelerator may be used in combination with O, OO in an amount of 1 to 0.05% by weight in the case of an organic peroxide.

As the polymerization method, all well-known polymerization techniques can be applied by those skilled in the art. For example, after adding a curing agent to a polymerizable syrup and mixing it well, it is poured into a mold made of two glass or metal plates sandwiching a gasket such as a vinyl chloride resin tube, and the polymerization is carried out at room temperature or under heating. In the cell-casting method, a molding space is formed by two stainless steel endless belts that run opposite each other and a pair of continuous soft-M polyvinyl chloride gaskets that run at the same speed on both sides of the belt. There is a continuous casting method, in which a polymerizable syrup that has been thoroughly mixed and degassed is continuously injected into the molding space, and polymerization is proceeded under heating.

It should be noted that known coloring agents, mold release agents, flame retardants, fillers, reinforcing agents, etc. that are normally used in the polymerization of methacrylic resins may be blended at will.

<Effects of the Invention> The methacrylic resin of the present invention maintains the excellent optical properties, weather resistance, hardness, and other properties originally possessed by methacrylic resin, and also has excellent properties in heat resistance and impact resistance. It is. Therefore, the methacrylic resin of the present invention can be used for signboards,
It can be effectively used in various applications such as glazing materials, interiors, automobile parts, and electrical equipment parts.

<Examples> The present invention will be specifically described below with reference to Examples, but the present invention is not limited thereto.

In addition, "parts" in the examples are by weight unless otherwise specified.

Reference Example 1 The following raw material mixture was charged into a reactor equipped with a stirrer, a cooler, a thermometer, a nitrogen inlet, and a dropping funnel, and polymerized for 5 hours at the reflux temperature of benzene while stirring under a nitrogen stream, and then under reduced pressure. At the bottom, benzene and unreacted monolayer were distilled off to synthesize a carboxyl group-containing acrylic elastomer.

Butyl acrylate 85 parts Methyl methacrylate 5 parts Styrene
Part 5 Acrylic II!
5 parts 2.2' -Azobisisobutyronitrile 2 parts Benzene 50 parts This elastomer has a molecular weight (weight average) of approximately 90°000.
The carboxyl fund m was 0.58 meq/g and the Tg was about -42°C. In a reactor similar to that used in the above reaction, 30 parts of the carboxyl group-containing acrylic elastomer obtained by the above reaction and 70 parts of methyl methacrylate were charged and dissolved with stirring at 70°C. Next, 2 parts of N-methacryloylaziridine was added over 30 minutes, and the mixture was further maintained at the same temperature for 4 hours to obtain a methyl methacrylate solution of the reactive elastomer. 70 parts of methyl methacrylate, 20 parts of α-methylstyrene and 110 parts of maleic anhydride were added to the resulting solution, and a polymerizable syrup (1
) was obtained.

Reference Example 2 In Reference Example 1, 1.4 parts of 2-(1-aziridinyl)ethyl methacrylate and 1.4 parts of cyclohexyl isocyanate were used instead of 2 parts of N-methacryloylaziridine.
Polymerizable syrup (2) was obtained by repeating the method of Reference Example 1, except that 1 part of α-methylstyrene was used and 20 parts of α-methylstyrene was replaced with paramethylstyrene.

Reference Example 3 A reactor similar to that used in Reference Example 1 was charged with the following raw material mixture, and a carboxyl group-containing acrylic elastomer was synthesized in the same manner as in Reference Example 1.

Butyl acrylate 86 parts Methyl methacrylate 6 parts Styrene
Part 6 acrylic FM
2 parts 2.2' -Azobisinbutyronitrile 2 parts Benzene 50 parts This elastomer has a molecular [1 (weight average)
The carboxyl group content was 0.23 milliequivalent m/g, and the Tg was about -43°C. 30 parts of the carboxyl group-containing acrylic elastomer obtained by the above reaction, 70 parts of methyl methacrylate, and 30 parts of styrene were charged into a similar reactor and dissolved with stirring at 70°C. Then, N
- After adding 2 parts and 8 parts of methacryloyl aziridine and further maintaining the same temperature for 5 hours, 120 parts of anhydrous maleic W and 50 parts of methyl methacrylate were added to obtain a polymerizable syrup (3).

Reference Example 4 In Reference Example 3, 0.6 part of 2-(1-aziridinyl)ethyl acrylate and 0 part of isopropylisocyanate were used instead of 0.8 part of N-methacryloylaziridine.
．． Repeat the method of Reference Example 3 except for using 4 parts,
A polymerizable syrup (4) was obtained.

Reference Example 5 The method of Reference Example 3 was followed except that 1.2 parts of glycidyl methacrylate and 0.02 parts of benzyldimethylamine (catalyst) were used instead of 0.8 parts of N-methacryloylaziridine. By turning the mixture, a polymerizable syrup (5) was obtained.

Reference Example 6 The method of Reference Example 3 was repeated except that 3.6 parts of 2-hydroxyethyl methacrylate was used instead of 2 parts of acrylic acid to obtain an acrylic elastomer having a hydroxyl group. This elastomer 3
0 parts, 70 parts of methyl methacrylate, and 30 parts of styrene were placed in a similar reactor and dissolved at 60°C with stirring. Next, 2 parts of isophorone diisocyanate was added and the temperature was maintained for 1 hour, then the temperature was raised to 80°C, 1.2 parts of 2- and droxyethyl methacrylate were added, and the temperature was maintained for an additional 2 hours. As a result, a methyl methacrylate solution of a reactive elastomer was obtained.

Subsequently, 20 parts of anhydrous maleiso M and 50 parts of methyl methacrylate were added to this solution to prepare polymerizable syrup (6).
I got it.

Reference Example 7 Ni with a free carboxyl group of 0.71 mm/g was placed in a reactor equipped with a stirrer, a cold water vessel, a thermometer, and a dropping funnel.
1) 30 parts of 01-1072B (carboxylated acrylonitrile-butadiene rubber, manufactured by Nippon Zeon Co., Ltd.) and 70 parts of methyl methacrylate were charged, and after swelling day and night, the rubber was dissolved at 70°C with stirring. Next, 2.5 parts of N-methacryloylaziridine was added over 30 minutes, and the mixture was further maintained at the same temperature for 4 hours to obtain a methyl methacrylate solution of the reactive elastomer. 30 parts of methyl methacrylate, 40 parts of paramethylstyrene, and 30 parts of maleic anhydride were added to the obtained solution to obtain a polymerizable syrup (γ).

Comparative Reference Example 1 30 parts of a carboxyl group-containing acrylic elastomer synthesized by the same method as Reference Example 1 and 14 parts of methyl methacrylate
0 parts, 20 parts of α-methylstyrene and 1 part of maleic anhydride
0 part was dissolved under stirring to obtain comparative syrup (1).

Comparative Reference Example 2 In Reference Example 1, additionally mixed methyl methacrylate 7
0 parts, 20 parts of α-methylstyrene and 1 part of maleic anhydride
The comparative syrup (
2) was obtained.

Comparative Reference Example 3 120 parts of carboxyl group-containing acrylic elastomer synthesized in the same manner as Reference Example 1, 5 parts of methyl methacrylate
After dissolving 20 parts of α-methylstyrene and 20 parts of α-methylstyrene in 70″C3 with stirring, 8 parts of N-methacryloylaziridine was added, and after further holding at the same temperature for 5 hours, 10 parts of maleic anhydride was added. However, a comparative syrup (3) was obtained in which the amount of reactive elastomer was outside the range of the present invention.

Examples 1 to 7 and Comparative Examples 1 to 3 Polymerizable syrups obtained in each reference example and comparative reference example (
1) to (7) and comparative syrups (1) to (3), each containing 0.2 parts as a hardening agent per 100 parts of the syrup.
2.2 parts of azobisisobutyronitrile was added, mixed well, and defoamed under reduced pressure to obtain a casting syrup. Each of the obtained casting syrups was poured between two glass plates sandwiching a vinyl chloride resin gasket, left to stand in warm water at 60°C to polymerize for 5 hours, and then placed under hot air at 110°C for 1 hour. hold to complete curing,
The mixture was cooled and demolded to obtain a sheet-like methacrylic resin having a thickness of 3#I. The physical properties of these resins were as shown in Table 1. The physical properties were measured in accordance with the following standards.

Claims (1)

[Claims] 1. Reactive elastomer (A) 0.5-50% by weight, aromatic vinyl monomer (B) 1-50% by weight, maleic anhydride (C) 1-25% by weight, methacryl Methyl acid (D) 40 to 97.5% by weight and other monomers (E) copolymerizable with these 0 to 40% by weight (However, (A), (B), (C), (D) A methacrylic resin with excellent heat resistance and impact resistance obtained by polymerizing a polymerizable syrup consisting of 100% by weight of components (E) and (E).