JPS6099114A - Impact-resistant methacrylic resin composition - Google Patents

Abstract

PURPOSE:The titled composition slightly being influenced by molding conditions, having improved properties of acrylic resin such as transparency, etc. of its own and improved impact resistance, obtained by polymerizing monomers consisting essentially of methyl methacrylate in the presence of a specific acrylic elastomer having multi-layer construction. CONSTITUTION:In the presence of (A) 100pts.wt. acrylic elastomer having multi- layer construction comprising (i) 5-50pts.wt. rigid crosslinked resin having >=80 wt% methyl methacrylate unit in the interior of particles and (ii) an outer layer having 95-50pts.wt. crosslinked acrylic acid ester copolymer obtained by polymerizing 69.9-89.9wt% 1-8C alkyl group-containing acrylic acid alkyl ester with 30-10wt% styrene, 0.1-10wt% substance shown by the formula, and 0- 5wt% another polyfunctional monomer containing plural C=C bonds, (B) 10- 100pts.wt. monomer (mixture) consisting of (iii) 80-100wt% methyl methacrylate, (iv) 0-20wt% 1-8C alkyl group-containing acrylic acid lakyl ester, and (v) 0- 10wt% another vinyl monomer is polymerized, to give the desired composition having multi-layer construction.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a methacrylic resin composition, and more specifically,
The present invention relates to a methacrylic resin composition that does not impair the inherent properties of methacrylic resin such as transparency, surface appearance, weather resistance, and flow processability, is less susceptible to molding conditions, and has excellent impact resistance.

[Technical background of the invention and its problems]

Methacrylic resin has excellent transparency and optical properties among plastic materials, and is also extremely excellent in surface gloss, weather resistance, dye and pigment colorability, and moldability. Taking advantage of these characteristics, lighting, signboards, window materials,
It is used in many fields such as optical lenses, 8 displays for vehicle parts, etc.

However, methacrylic resin has the problem of insufficient impact resistance, and its improvement is strongly desired in each application field.

For information on how to impart impact resistance to methacrylic resin,
Although many proposals have been made for a long time, the reality is that no impact-resistant methacrylic resin material has yet emerged that possesses the original characteristics of methacrylic resin, such as transparency, appearance, weather resistance, and moldability. .

Many of these methods consist of dispersing a rubbery elastomer in a methacrylic resin at room temperature. Examples of the rubbery elastic body include an unsaturated rubbery elastic body mainly composed of butadiene, an acrylic ester copolymer mainly composed of butyl acrylate, 2-ethylhexyl acrylate, etc., or an ethylene/vinyl acetate copolymer. Saturated rubber-like elastomers such as coalesces are used.

Although the introduction of an unsaturated rubber-like elastic material is excellent in terms of impact resistance, there is a problem of poor weather resistance due to the unsaturated bonds in the polymer main chain.On the other hand, the introduction of a saturated rubber-like elastic material Although it has excellent weather resistance, the elastic modulus and elastic recovery of the rubber component itself are low, and it also has poor graft polymerizability with hard resin components, so it has good impact resistance and transparency.

There are also problems with the surface appearance, such as poor surface gloss and a flowing pattern. In general, when synthesizing an impact-resistant resin consisting of a two-component system in which these rubber elastic bodies are uniformly dispersed as particulate discontinuous phases in a continuous phase of hard resin such as methacrylic resin, an important factor is The particle size of the elastic body, the degree of crosslinking, the graft polymerizability of the hard resin phase to the rubber phase, the molecular weight of the hard resin phase, etc. are listed. In fact, the quality and balance of the resin properties of the final resin composition are greatly influenced by these factors.

In other words, the smaller the particle size of the rubber-like elastic body, the better the transparency, but the poorer the effect of developing impact resistance. Although it has excellent surface gloss, it has the disadvantage of poor impact resistance.

Similarly, the degree of graft polymerization of the hard resin phase to the rubbery elastomer is similar to that of the rubbery elastomer to the continuous resin phase.

Compatibility 2 largely controls dispersibility, impact resistance, and transparency.

Stress whitening resistance 9 affects many properties such as surface gloss and flow processability, and when using a saturated rubber-like elastomer,
Graft polymerizability is generally low and special consideration must be taken. A larger molecular weight of the hard resin phase is more effective in terms of impact resistance, but it is conversely inferior in terms of moldability and surface appearance of the final resin composition.

In recent years, impact-resistant resin compositions or impact-resistant methacrylic resin compositions in which the rubber phase is made of acrylic acid ester-based elastic materials that have deteriorated in weather resistance have been studied. , a method of incorporating a hard resin core inside rubber particles has been proposed for the purpose of improving stress whitening resistance or pearl-like luster 2 caused by deformation of rubber particles during the molding process (Japanese Patent Publication No. 1973- No. 30996 and JP-A No. 48-55233, U.S. Patent No. 3°661
．． No. 994, U.S. Pat. No. 3,793,402), although these methods are certainly effective, when viewed as a methacrylic resin material, it is still quite inferior in terms of transparency and surface gloss, and these characteristics are There is a problem in the molding process that the amount varies depending on the molding conditions.

In addition, in order to improve the graft polymerizability of the hard resin phase to the acrylic ester-based elastomer, specific species having multiple double bonds with different reactivities, such as allyl methacrylate and diallyl maleate, are added to the rubber-like elastomer phase. A formulation has been proposed in which a monomer (referred to as a graft-crossover monomer) is introduced by copolymerization. (Japanese Patent Application Laid-open No. 48-55233, US Pat. No. 3,793,402). These methods certainly tend to improve graft polymerizability, but this type of monomer is widely used as a crosslinking agent, and the graft polymerizability is Both moieties that contribute to polymerization are present, and it is extremely difficult to control the effects on these two reactions. For these reasons, these methods are also far from perfect.

[Purpose of the invention]

The object of the present invention is to eliminate the above-mentioned drawbacks, namely:
To provide a methacrylic resin composition which does not impair the original properties of methacrylic resin such as transparency, surface appearance, weather resistance and flow processability, is not affected by molding conditions, and has excellent impact resistance.

[Summary of the invention]

As a result of extensive studies to achieve the above-mentioned object, the present inventors discovered that when polymerizing an acrylic acid alkyl ester containing a hard crosslinked resin mainly composed of methyl methacrylate inside the particles, a special structure was found. A specific amount of a crosslinking monomer having the following is used as a copolymerization component, and a monomer containing methyl methacrylate as a main component or a mixture thereof is graft-polymerized to form a hard resin. It was discovered that the original objective could be achieved by blending and dispersing it in ivy resin, and the present invention was completed.

That is, the methacrylic resin composition of the present invention comprises a hard crosslinked resin (A
) 5 to 50 parts by weight inside the particles, 69.9 to 89.9 i% by weight of at least one acrylic acid alkyl ester whose alkyl group has 1 to 8 carbon atoms, styrene alone or a mixture of styrene and its derivatives 30 to 10% by weight and at least 0.1 to 10% by weight of at least one substance represented by the following formula: A multilayer structure acrylic whose outer layer is composed of 95 to 50 parts by weight of a crosslinked acrylic acid ester copolymer (B) obtained by polymerizing a monomer mixture consisting of 0 to 5% by weight of other polyfunctional monomers. In the presence of 100 parts by weight of system elastic body CI), 80 to 100% by weight of methyl methacrylate,
A monomer or monomer consisting of O to 20% by weight of at least one acrylic acid alkyl ester having 1 to 8 carbon atoms and 0 to 10% by weight of another vinyl monomer copolymerizable therewith. It is obtained by polymerizing 10 to 1000 parts by weight of polymer mixture (C), and further contains 80 to 100 weight % of methyl methacrylate and 0 to 20 weight % of other vinyl or vinylidene monomers. % methacrylic resin, which is a monomer or a mixture thereof [
(2)] and 0.5 to 70% by weight of the multilayered acrylic elastic body [I] is contained in the composition.

As mentioned above, the most important feature of the present invention is that during the polymerization of a crosslinked acrylic acid alkyl ester copolymer containing a hard crosslinked resin core, a substance having a special structure represented by the above formula is produced. The point is that a specific amount is used as a crosslinking agent.

The hard crosslinked resin phase (A) used in the present invention, the non-crosslinked hard resin phase, and the methacrylic resin (I[
In [), in order to provide good transparency, the monomer composition except for the auxiliary agents and crosslinking monomer components that are individually required at each polymerization step should be the same or very similar. is desirable. In addition, cross-linked acrylic ester polymers (
It is also preferable that the refractive index of B) is made very similar to that of the hard resin segment.

Furthermore, in a resin composition obtained by dispersing rubber particles in a continuous resin phase, it is necessary to consider the diameter of the dispersed rubber particles in order to balance transparency, surface appearance, and impact resistance performance. In the composition of the present invention, in order to obtain a composition excellent in both transparency and impact resistance, at the time when the polymerization of the crosslinked acrylic acid ester polymer (B) is substantially completed, , more preferably 0.2-0
．． A particle size range of 35 μm is preferable.

The multilayer structure acrylic elastic body CI) in the present invention has a hard crosslinked resin (A) containing 80% by weight or more of methyl methacrylate units inside the particles, and a crosslinked acrylic ester polymer (B) in the outer layer. It consists of a structure with

The hard crosslinked resin (A) in the present invention is methyl methacrylate alone or 80 to 100% by weight of methyl methacrylate and other copolymer vinyl or vinylidene monomer 0 to 20% by weight.
To 100 parts by weight of a monomer or monomer mixture consisting of,
A copolymer obtained by adding 0.1 to 10 parts by weight, more preferably 0.5 to 5 parts by weight, of a crosslinking monomer is added to a multilayer acrylic elastomer (13,100 parts by weight). It is necessary to contain 5 to 50 parts by weight, more preferably 10 to 40 parts by weight.If the amount is less than 5 parts by weight, the effect of developing impact resistance will be small and the transparency will also decrease. If the amount exceeds 1 part by weight, the surface gloss tends to decrease and the impact resistance also tends to decrease.

The vinyl or vinylidene monomer copolymerizable with methyl methacrylate used in the polymerization of the hard crosslinked resin (A) includes styrene, acrylonitrile, and alkyl groups having 1 to 1 carbon atoms.
8, acrylic acid alkyl esters, and the like.

Further, the crosslinkable monomer used in the polymerization of the hard crosslinked resin (A) is not particularly limited as long as it is copolymerized with methyl methacrylate, and commonly used ethylene glycol dimethacrylate, ethylene glycol diacrylate, Bifunctional monomers such as 1,3-butylene dimethacrylate and tetraethylene glycol diacrylate, or trifunctional monomers such as trimethylolpropane triacrylate, triallyl cyanurate, triallyl isocyanunate, or penta Tetrafunctional monomers such as erythritol tetraacrylate can be used alone or in combination.

The crosslinked acrylic ester copolymer (B) is preferably at least one of n-butyl acrylate and 2-ethylhexyl acrylate among the acrylic alkyl ester group having an alkyl group having 1 to 8 carbon atoms.69. 9-89.
9% by weight and 10-30% by weight of styrene alone or a mixture of styrene and its derivatives, and 0.1-10% by weight of at least one substance represented by the general formula: It is a copolymer and is polymerized into the outer layer in the presence of the hard crosslinked resin (A). The composition ratio of the acrylic acid ester monomer and styrene or a mixture of styrene and its derivatives is one of the important factors for imparting transparency, and transparency decreases outside the above composition range. The substance represented by the above general formula is one of the most important parts of the factors constituting the present invention, and thereby achieves the object of the present invention. Although the details of its effect are not clear, it is inferred that this is because the degree of crosslinking of the crosslinked acrylic ester copolymer (B) and the graft polymerizability with methyl methacrylate are controlled in a well-balanced manner. The appropriate amount of addition differs depending on whether it is used alone or in combination, but the amount is 0.1 to 1
o The range of weighted background % is appropriate. In addition to the substances represented by the general formula, a known polyfunctional monomer can also be used in an amount of 0 to 5 M%. Further, this polyfunctional monomer does not need to be particularly limited and is one commonly used. As specific compounds, ethylene glycol di(meth)acrylate-1-, L3 butylene di(meth)acrylate, tetraethylene glycol di(meth)acrylate, divinylbenzene, etc. can be used.

The multilayer structure methacrylic resin composition (II) of the present invention is obtained by polymerizing a monomer or a monomer mixture (C) in the presence of a multilayer structure acrylic elastic body (1). The component composition is methyl methacrylate 8O-10
0i weight %, at least one type of acrylic acid alkyl ester having an alkyl group of 1 to 8 carbon atoms, O to 20 weight %, and 0 to 10 weight % of other vinyl monomers copolymerizable therewith.
It consists of the following:

If the content of methyl methacrylate in the i-mer or monomer mixture (c) is 80% by weight, the properties such as transparency and heat resistance will be poor, and the acrylic acid copolymerized with the glue will deteriorate. Examples of alkyl esters include methyl acrylate, ethyl acrylate, butyl acrylate, and the like. Other vinyl monomers that can be used as copolymerization components include styrene, acrylonitrile, and methacrylic acid. If the amount of acrylic ester exceeds 20% by weight in the monomer or monomer mixture (C), it is not preferable in terms of heat resistance and transparency of the final composition (and other copolymerizable vinyl monomers). If the amount exceeds 10% by weight, it is unfavorable in terms of transparency, heat resistance, water resistance, etc.

The monomer or monomer mixture (C) must be polymerized in an amount of 10 to 1000 parts by weight based on 100 parts by weight of the multilayered acrylic elastic body (1). If it is less than 10 parts by weight, it is not preferable because impact resistance may be poor or surface gloss may be reduced. On the other hand, if it exceeds 1000 parts by weight, productivity decreases, which is not preferable. For the monomer or monomer mixture (C), a polymerization degree regulator such as mercaptan may be used as necessary to adjust the molecular weight as necessary. Examples of the polymerization degree regulator that can be used include alkyl mercaptans, thioglycolic acid and its esters, β-mercaptopropionic acid and its esters, and aromatic mercaptans such as thiophenol and thiocresol.

The invention of - of the present invention consists of the above-mentioned multilayer structure methacrylic resin composition CI [ It is made by blending the system elastic body (1).

The methacrylic resin CI) of the present invention can be used for other thermoplastic resins,
Preferably 80-100% by weight of methyl methacrylate and 0
It is a polymer with ~20% by weight of other vinyl or vinylidene monomers, such as acrylic esters having alkyl groups of 1 to 4 carbon atoms.

Another invention of the present invention is a composition in which a multilayer structure methacrylic resin composition (II) is mixed with a methacrylic resin [■] to contain 0.5 to 70% by weight of a multilayer structure acrylic elastic body CI). .

Since it is particularly preferable to manufacture the multilayered methacrylic resin composition of the present invention by emulsion polymerization, an example in which emulsion polymerization is used will be described.

After adding salt ion water and an emulsifier if necessary to a reaction vessel, the monomer mixture constituting the hard crosslinked resin (A) is polymerized, and then the monomer mixture constituting the crosslinked acrylic ester copolymer (B) is polymerized. The polymer mixture is polymerized, and then the monomer or monomer mixture (C) is polymerized.

Polymerization temperature is 30-120°C, more preferably 50-10°C
It is 0°C.

The polymerization time varies depending on the type and amount of the polymerization initiator and emulsifier, the polymerization temperature, etc., but generally speaking, the polymerization time for each polymerization step (A),
(B) and (C) each takes 0.5 to 7 hours.

The ratio of polymer to water is preferably monomer/water - 1/20 to 1/1.

The polymerization initiator and emulsifier can be added to either or both of the aqueous monomer phase.

The monomers in the polymerization steps (A), (B), and (C) can be charged all at once or in portions, but the method of charging in portions is more preferable from the viewpoint of heat generation during polymerization.

The emulsifier is not particularly limited as long as it can be used as a current-carrying agent, and examples of emulsifiers that can be used include long-chain alkyl carboxylates, sulfonic acid alkyl ester salts, and alkylbenzene sulfonates.

There is no need to particularly limit the type of polymerization initiator, and redox can be initiated by using a water-soluble inorganic initiator such as persulfate or perborate alone or in combination with sulfite, thiosulfate, etc., which requires a current-carrying agent. It can also be used as an agent. Further, redox initiation systems such as organic hydrogen dosodium sulfoxylate, benzoyl peroxide, azobisisobutyronitrile, and other initiation systems can also be used.

The polymer latex obtained by the emulsion polymerization method is coagulated and dried by a known method.

When blending and dispersing the obtained multi-structure methacrylic resin composition into other methacrylic resins, a melt-mixing method is ideal. Prior to melt mixing, if necessary in addition to the resin composition, stabilizers, lubricants 7 plasticizers, dyes and pigments 5 fillers, etc. are added as appropriate and mixed using a V-type blender or Henschel mixer, followed by mixing rolls or screw type extrusion. The mixture is melt-kneaded at 150°C to 300°C using a machine or the like.

By molding the resulting composition using an extrusion molding machine, an injection molding machine, etc., it is possible to obtain a molded product having excellent transparency (9), surface gloss, and high impact resistance.

〔Effect of the invention〕

As detailed above, the methacrylic resin composition of the present invention does not impair the inherent properties of methacrylic resin such as transparency, surface appearance, weather resistance, and flow processability, and is not easily affected by molding conditions. Moreover, it has excellent impact resistance, and its industrial value is extremely large.

The present invention will be explained in more detail below based on Examples. In the examples, parts represent parts by weight, and % represents weight %.

[Embodiments of the invention]

Examples 1 to 2 (1) Production details of hard crosslinked resin (A) First, the following raw materials (A) were charged in various proportions into a 11100J2 stainless steel reaction vessel, and nitrogen was blown in with stirring to substantially eliminate oxygen. After making it unaffected, 7
The temperature was raised to 0° C., the following raw materials (b) were added, and polymerization was carried out for 2 hours to obtain a hard crosslinked resin latex.

(a) Raw material boric acid 100g Soda carbonate 10g (BDMA) (B) Raw material deionized water 1 kg Potassium persulfate (KPS) 30g *1) MMA of latex of N-acyl sarcosinate (product of Nikko Chemicals Co., Ltd.) The polymerization rate was 98.5% and the particle size was 0.16 μm.

(2) Production of multilayered acrylic elastomer CI) by polymerization of crosslinked acrylic ester copolymer (B) The solid content after the polymerization in (1) above is substantially completed is 1.5 k
In the above container containing the hard crosslinked resin latex of g,
After adding the following aqueous solution of sodium formaldehyde sulfoxylate (hereinafter referred to as longaliisoto) and sarcosinate N, and raising the temperature to 80°C, an acrylic acid ester monomer mixture having the composition ratio shown in Table 1 was added. 5k
Tertiary butyl hydroperoxide (TB
H) 38g was added continuously over 150 minutes. After the addition was completed, polymerization was continued for another 3 hours,
A latex of a multilayer structure acrylic elastic body (1) containing the hard crosslinked resin (A) inside the particles was obtained.

Sarcosinate LN 2Qg Rongalisoto 32g Deionized water 1kg In all of the above cases, the polymerization yields of BA and ST were 97% and 99.5% or more, respectively, and the particle size of the obtained latex was 0.26-0. It was 28 μrn.

(3) Production of multilayer methacrylic resin composition (II) by polymerization of monomer mixture (C) Solid content of multilayer acrylic elastomer (1) obtained in the above polymerization (2): 10k
After adding 25 g (0.25 parts) of sarcosinate LN and 1 kg (10 parts) of deionized water into the above container containing 1 kg (100 parts) of latex and stirring, the following monomer mixture ( C) was added continuously over 2.5 hours. Thereafter, polymerization was continued for an additional hour to obtain a multilayered methacrylic resin composition (n) in the form of latex.

The polymerization yield of MMA in the monomer mixture (C) was 99.5% or more in all cases.

Monomer mixture (C) (n Ca S H) TBH90g (0.9 parts) This latex is solidified by the method described below.

After washing and drying, the multilayered methacrylic resin composition (III
of powder was obtained.

Pour 140 kg of 1.0% sulfuric acid water into a stainless steel container and raise the temperature to 80°C while stirring to obtain 70 kg of latex produced earlier.
g was added continuously over 20 minutes, and then the internal temperature was raised to 95°C and held for 5 minutes. After cooling to room temperature, the polymer was filtered off and washed with deionized water to obtain a white creamy polymer, which was dried at 70° C. for 24 hours to obtain a white powdery polymer.

Next, this powder was transferred to a screw type extruder with an outer diameter of 40 mm (
Nippon Steel Shinsei Co., Ltd., P-40-26AB-V type, L
/D=26), cylinder temperature 235-255
℃, the molding conditions were changed to 50 to 70℃, and the multilayered acrylic elastic body (1) was melted and kneaded to form pellets.
An impact-resistant methacrylic resin composition having a content of 25% was obtained.

This was injection molded under the following conditions, and the evaluation results shown in Table 2 were obtained from the obtained test pieces.

Injection molding machine: V-17-65 type screw complete automatic injection molding machine manufactured by Japan Steel Works, Ltd. Injection molding conditions: Cylinder temperature 259°C.

Injection pressure 700 kg/cJA Test piece size: 110 dragons x 110 dragons x 2 cranes (thickness) 70 dragons x 12.5 dragons x 6.21 (thickness) As is clear from the above results, the methacrylic resin of the present invention It was confirmed that even when the composition was molded under different molding conditions, the properties and impact resistance inherent to the methacrylic resin were not impaired at all.

Examples 3 to 5; Comparative Examples 1 to 3 (1) Production of hard crosslinked resin (A) Into a stainless steel reaction vessel with an internal volume of 5ON, the following raw materials (A) were first put in various proportions, and nitrogen was added under stirring. After blowing into the mixture to make it substantially free from the influence of oxygen, the temperature was raised to 70°C, the following raw materials (b) were added, and polymerization was carried out for 2 hours to obtain a hard crosslinked resin latex.

(a) Raw material boric acid 100g Soda carbonate log (b) Raw material deionized water 1 kg Potassium persulfate (KPS) 30g *1) N-acyl sarcosinate (product of Nikko Chemicals Co., Ltd.) The polymerization rate of MMA in this latex is At 98.5%, the particle size was 0.16 μm.

(2) Production of multilayered acrylic elastomer CI) by polymerization of crosslinked acrylic ester copolymer (B) The solid content after the polymerization in (1) above is substantially completed is 1.5 k
The following aqueous solutions of sodium formaldehyde sulfoxylate (hereinafter referred to as Rongalit) and Sarcosine (Sarcosine) LN were added to the container containing an amount of hard crosslinked resin latex equivalent to 32 g of tertiary butyl hydroperoxide (TBH) was added continuously to 8.5 kg of an acrylic acid ester monomer mixture having the composition ratio shown in Table 3 over a period of 150 minutes. After the addition was completed, polymerization was continued for another 3 hours to obtain a latex of a multi-layered acrylic elastic body (1) containing the hard crosslinked resin (A) inside the particles.

Sarcosinate LN 30g Rongalite 32g Deionized water 500g The polymerization rate of BA in this polymerization in Example-3 was 9
The polymerization rate of ST was 99%, and the particle size of the obtained latex was 0.25 μm.

(3) Production of multi-layered methacrylic resin composition (II) by polymerization of monomer mixture (C) (multi-layered acrylic elastomer CI obtained in (2) above)
A latex equivalent to 10 kg of solid content was placed in a separate reaction vessel, and 500 g of deionized water and 25 g of sarcosinate LN were added thereto and stirred.Then, the temperature was raised to 80°C, and 4 kg of the following monomer mixture (C) was added. The additions were made continuously at a rate of 1/2 hours. Thereafter, polymerization was continued for an additional hour.

A multilayered methacrylic resin composition (II) was obtained in the form of latex. The polymerization rate of monomer mixture (C) is 99.5
% or more.

Monomer mixture (C) TBH40g This latex is solidified by the method described below.

After washing and drying, a powder of the multilayered methacrylic resin composition [■] of the present invention was obtained.

120 kg of 1.0% sulfuric acid water was placed in a stainless steel container, and the temperature was raised to 70°C while stirring to form the latex 60 produced earlier.
kg was added continuously over 15 minutes, and then the internal temperature was raised to 90°C and held for 5 minutes. After cooling to room temperature, the polymer was filtered and washed with deionized water to obtain a white creamy polymer, which was dried at 70° C. for 24 hours to obtain a white powdery polymer.

Next, 250 parts of the powder of the multilayered methacrylic resin composition CHI obtained in (3) above and 250 parts of acrylic resin [■] (Acrypet VH, a product of Mitsubishi Rayon Co., Ltd.) were mixed using a Henschel mixer. After that, Example 1~
Using the screw type extruder used in 2, the cylinder temperature was 200 to 270°C and the temperature was 260°C to melt and knead the pellets to obtain the original multilayered methacrylic resin. Evaluation was conducted in the same manner, and the results shown in Table 4 were obtained.

From the above results, acrylic ester copolymer (B)
It was confirmed that by using the substance represented by formula (1) used in the present invention during polymerization, it is possible to improve impact resistance while maintaining the original characteristics of methacrylic resin.

Examples 6-7. Comparative Examples 4-7. Among the series of production methods of Examples 3 to 5, only the monomer composition of the parts shown in Table 5 was changed to obtain a multilayer structure methacrylic resin composition (II),
Evaluations were made in exactly the same manner as in Examples 3 to 5, and the results shown in Table 6 were obtained.

As is clear from the above results, when the substance of the general formula; Even if it is added, it is outside the scope of use of the present invention (Comparative Example 6.7)
), and further when the core of the hard crosslinked resin (A) is not contained inside even if the amount added is within the usage range of the present invention (Comparative Example 8)
), it can be seen that the object of the present invention cannot be achieved.

Claims (1)

[Scope of Claims] 1. Acrylic acid alkyl ester containing 5 to 50 parts by weight of a hard crosslinked resin (A) containing 80% by weight or more of methyl methacrylate units inside the particles, and in which the alkyl group has 1 to 8 carbon atoms. (69.9 to 89.9% by weight of each type; 30 to 10% of styrene alone or a mixture of styrene and its derivatives)
0.1 to 10% by weight of at least one of the substances represented by the general formula: % formula %; and other substances that can be copolymerized with these substances and have two or more carbon-carbon double bonds in one molecule. A multilayer structure acrylic elastomer whose outer layer is composed of 95 to 50 parts by weight of a crosslinked acrylic ester copolymer (B) obtained by polymerizing a monomer mixture consisting of 0 to 5% by weight of a polyfunctional monomer. CI) in the presence of 100 parts by weight, 80 to 100 weight % of methyl methacrylate; 0 to 20 weight % of at least one acrylic acid alkyl ester having an alkyl group having 1 to 8 carbon atoms; and copolymerizable with this. Monomer or monomer mixture (C) consisting of 0 to 10% by weight of other vinyl monomers (C) 10 to 100%
An impact-resistant methacrylic resin composition comprising a multilayer structure methacrylic resin composition (n) obtained by polymerizing 0 parts by weight. 2. At least one type of acrylic acid alkyl ester containing 5 to 50 parts by weight of a hard crosslinked resin (A) containing 80% by weight or more of methyl methacrylate units inside the particles, and having an alkyl group having 1 to 8 carbon atoms 69. 9 to 89.9% by weight; styrene alone or a mixture of styrene and its derivatives 30 to 10
0.1 to 10% by weight of at least one of the substances represented by the general formula: % formula %; and 0.1 to 10% by weight of at least one substance represented by the general formula: A multilayered acrylic elastomer whose outer layer is composed of 95 to 50 parts by weight of a 1M crosslinked acrylic ester copolymer (B) obtained by polymerizing a monomer mixture consisting of 0 to 5% by weight of a polyfunctional monomer. CI) In the presence of 100 parts by weight, 80 to 100 i weight % of methyl methacrylate, 0 to 20 weight % of at least one type of acrylic acid alkyl ester having an alkyl group having 1 to 8 carbon atoms, and others copolymerizable with this. A multilayer structure methacrylic resin composition (n) obtained by polymerizing 10 to 1000 parts by weight of a monomer or monomer mixture (C) consisting of 0 to 10]iii% of a vinyl monomer; Methacrylic resin (III) which is a polymer of a monomer or a mixture thereof consisting of 80 to 100% by weight of methyl acid and 0 to 20% by weight of other vinyl or vinylidene monomers
An impact-resistant methacrylic resin composition comprising 0.5 to 70% by weight of a multilayered acrylic elastic body CI'l. 3. The impact-resistant methacrylate according to claim 1 or 2, wherein the substance represented by the general formula ○ 1 C6H4 (-C-0-CH2-CH=CH,!) 2 is diallyl isophthalate. Resin composition. 4. The impact-resistant methacrylic resin composition according to claim 1 or 2, wherein the substance represented by the general formula (0% formula %) is diallyl terephthalate.