JPH0198653A - Methacrylic resin composition - Google Patents

Abstract

PURPOSE:To obtain the title composition excellent in impact and solvent resistances, by mixing a methacrylic resin with a specified multi-structure graft copolymer. CONSTITUTION:20-200pts.wt. mixture comprising 80-100% methyl methacrylate and 20-0% other copolymerizable vinyl or vinylidene monomers is copolymerized in the presence of 100pts.wt. rubberlike copolymer obtained by copolymerizing 74.8-84.9wt.% (1-8C) alkyl acrylate with 15-25% at least one macromonomer selected from styrene and vinyltoluene each having a polymerizable functional group on one end, 0.1-5% crosslinking monomer having at least two C-C double bonds and 0-20% other vinyl or vinylidene monomers to obtain a multi-structure graft copolymer (B) containing 0.1-50% rubberlike polymer. A methacrylic resin (A) obtained by polymerizing methyl methacrylate or copolymerizing this monomer with other copolymerizable vinyl or vinylidene monomers is blended with component B.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a methacrylic resin composition having excellent impact resistance and solvent resistance, and more specifically, a methacrylic resin composition containing methacrylate methacrylate as a main component. and a multi-structure graft copolymer having a specific structure, and a methacrylic resin composition that has excellent transparency and surface gloss, and also exhibits excellent impact resistance and solvent resistance in low temperature range and room temperature range. .

[Conventional technology]

Among polymer materials, methacrylic resin has excellent optical properties such as transparency and surface gloss, mechanical properties, and weather resistance, and also has excellent moldability. Taking advantage of these characteristics, lighting equipment, signboards,
It is used in many fields such as window materials, optical lenses, vehicle parts, and various displays.

However, since methacrylic resin lacks impact resistance, its improvement is strongly desired in many application fields, and the method of imparting impact resistance without impairing the original properties of methacrylic resin is outdated. It is being considered since. The present inventors also previously polymerized a monomer mixture of acrylic acid alkyl ester, styrene monomer, and diary isophthalate in the presence of an acrylic μ yarn elastic material, which contained methiμ methacrylate as the main component. A resin composition in which a graft copolymer obtained by graft copolymerizing a monomer or a mixture thereof and a methacrylic resin (Japanese Patent Application No. 1983-99115), and a resin composition containing methyl methacrylate as a main component A crosslinkable monomer and a non-crosslinkable monomer are polymerized in the presence of a double-structure acrylic elastic body containing a hard crosslinked resin inside and a crosslinked acrylic acid ester copolymer forming the outer layer. Resin composition (U.S.P.
No. 4.433.103, Japanese Unexamined Patent Application Publication No. 1987, No. 67712), etc.

In addition to these methods, many methods have been proposed in which acrylic acid alkyl esters and styrene monomers are used as rubbery elastomer components.

[Problem that the invention seeks to solve]

However, the glass transition point of the copolymer of acrylic acid alkyl ester and styrene monomer is
Glass transition point of Kip ester homopolymer (-50 to -6
%, 0 to -20°C, compared to 0°C), which had the disadvantage of affecting the elastomer properties in the low temperature range and reducing the ability to develop impact resistance.

[Means for solving problems]

In view of the above-mentioned problems, the present inventors have developed a method that provides impact resistance and solvent resistance that do not depend on temperature changes, without sacrificing the inherent properties of methacrylic resin such as transparency, surface gloss, moldability, and weather resistance. As a result of intensive studies to obtain a methacrylic resin composition that has been imparted with properties, we have combined acrylic acid alkyl ester μ, which is a component that imparts impact resistance, and styrene, which is a component that imparts transparency, into a block-shaped methacrylic resin composition. The present invention was accomplished by discovering that by polymerizing diacrylic acid acryl ester, transparency can be imparted while maintaining the low glass transition point.

That is, the present invention provides a methacrylic resin (
I) and at least one monomer (a) selected from acrylic acid aμyl esters having an alkyl group having 1 to 8 carbon atoms 74
．． 9 to 84.9% by weight, at least one selected from styrene and vinyltoluene having a polymerizable functional group at one end
15 to 25% by weight of a macromer (b) consisting of seeds, 1 to 5% by weight of a crosslinkable monomer α having two or more carbon-carbon double bonds, and 0 of other copolymerizable vinyl or vinylidene monomers. In the presence of 100 parts by weight of a rubbery copolymer (n) obtained by copolymerizing a monomer mixture (c) consisting of ~20 parts by weight, 80 to 100 parts by weight of methyl methacrylate and other copolymerizable Monomer mixture (d) consisting of 0 to 20 parts by weight of vinyl/L/l or vinylidene monomer (II)
I), wherein the rubbery copolymer (II) component of the multi-structure graft copolymer (m) is present in the entire composition.
The first invention is a methacrylic resin composition characterized by containing 1 to 50% by weight of IL. methacrylic resin CI) obtained by polymerizing the mixture, methyl methacrylate in an amount of 80 to 100% by weight based on the total weight of the rubbery copolymer (U), and other copolymerizable vinyl. Acrylic acid containing inside the particle a hard resin component obtained by polymerizing a monomer mixture consisting of A/or vinylidene monomer 0 to 20% by weight, and having an acrylic acid group having 1 to 8 carbon atoms. At least one selected from acyl esters
Macromer (b) consisting of 74.9 to 84.9% by weight of seed monomer (a) and at least one selected from styrene and vinyltoluene having a polymerizable functional group at one end
In the presence of a rubbery copolymer (n) obtained by copolymerizing a monomer mixture (c) consisting of 5 to 25% by weight and 0 to 20% by weight of carbon-carbon dimers, A multilayer structure graft obtained by polymerizing 20 to 200 parts by weight of a monomer mixture (d) consisting of 80 to 100 parts by weight of methyl methacrylate and 0 to 20 parts by weight of other copolymerizable vinyl or vinylidene monomers. copolymer (II), wherein the entire composition contains a multi-structure graft copolymer (m
) rubber-like copolymer (containing 11 to 50% by weight of force component) @2
invention.

The methacrylic resin (I) used in the present invention can be obtained by polymerizing methacrylic methacrylate alone or a mixture of methyl methacrylate and other copolymerizable vinyl/I/j or vinylidene monomers. It preferably contains 80% by weight or more of methyl methacrylate. Other copolymerizable vinyl/l/ or vinylidene monomers are preferably alkyl acrylates having 1 to B carbon atoms such as methyl acrylate, ethyl acrylate, butyl acrylate, and 2-ethylhexyl acrylate Vlv. Examples include ester, styrene, and acrylonitrium.

Next, the multi-structure graft copolymer (m) is composed of at least one monomer (6,) selected from acrylic acid alkyl p esters in which the alkyl group has 1 to 8 carbon atoms. ~8
4.991G, 15 to 25% by weight of a macromer (b) consisting of at least one selected from styrene and vinyltoluene having a polymerizable functional group at one end, and a crosslinkable monomer having two or more carbon-carbon double bonds. mass α1-5fold jtchi,
Other copolymerizable vinyl μ or vinylidene monomers 0 to 2
In the presence of 100 parts by weight of a rubbery copolymer (n) obtained by copolymerizing a monomer mixture (c) consisting of 0% by weight, methymethacrylate/L/80 to 100% by weight and other copolymers It is obtained by polymerizing 20 to 200 parts by weight of a monomer mixture (d) consisting of 0 to 20 parts by weight of a vinyl or vinylidene monomer.

As the monomer (a), acrylic acid butyμ, acrylic acid 2
-Ethylhexy μ is particularly preferred.

Further, the macromer (b) preferably has a (meth)acryloyloxy group at one end as a polymerizable functional group. Furthermore, the molecular weight is preferably in the range of 1.000 to 10.000; if the molecular weight is less than 1,000, the glass transition point of the rubbery copolymer (II) will increase, and the impact resistance at low temperatures will not be improved. On the other hand, when the molecular weight exceeds 10,000, stable polymerization cannot be carried out, especially in the case of emulsion polymerization, and a decrease in transparency is observed due to the formation of giant particles.

From the viewpoint of transparency, the monomer (-) and macromer (b) are used in a proportion of 74% each in the rubbery copolymer (II).
．． It is necessary that the amount is 9 to 84.9 weight percent and 15 to 25 weight percent.

Next, the proportion of the crosslinkable monomer having two or more carbon-carbon double bonds used in producing the rubbery copolymer (TI) is 11 to 5% by weight.

The crosslinkable monomer is not particularly limited, and includes ethylene glyco-μ di(meth)acrylate, 1,3-butylene di(meth)acrylate, and polyethylene glyco-μ di(meth)acrylate.
Acrylate, trimethylolpropane tri(meth)acrylate, Ari A/(meth)acrylate, Metali/
L/(meth)acrylate, aryl psobate, allyl cinnamate, triallyl cyanurate, triallyl iso V anurate, diallyl phthalate, diallyl isophthalate, diallyl maleate, diallyl fumarate, triallyl trimer Examples include tate, and these can be used alone or in combination of two or more.

In addition, other copolymerizable vinyl or vinylidene monomers can be used in an amount of 500 parts by weight, such as methyl methacrylate, ethyl methacrylate, buty-methacrylate, 2-ethyl hexyl methacrylate, etc. Carbon number 1 such as VJv
-8 methacrylic acid esters, styrene, acrylonitrile esters, and the like.

Furthermore, inside the rubbery copolymer (n), if necessary, methyl methacrylic acid fi/80 to 100% by weight as a core, based on the total weight of the rubbery copolymer (n), and other copolymerizable materials. It is also possible to contain a hard resin component obtained by polymerizing a monomer mixture consisting of 0 to 20 weight portions of vinyl Iv or vinylidene monomers. In this case, other copolymerizable vinyl/I/ or vinylidene monomers include acrylic acid esters having 1 to 8 carbon atoms, such as methacrylate, butyl acrylate, and 2-ethymuhexyl acrylate. Examples include μkiμ ester, styrene, acrylonitriμ, and the like. Furthermore, the aforementioned crosslinkable monomer having two or more carbon-carbon double bonds can also be used.

In addition, it is preferable that the rubbery copolymer (If) has a particle diameter of α05 to CL45 μm at the time of completion of polymerization. If the particle size is less than (LO5 μm), impact resistance will be poor, while if it exceeds (LO145 μm), transparency, surface gloss, etc. will tend to be poor.

Next, the multi-structure Gofuft copolymer (g) of the present invention is obtained by polymerizing the monomer mixture (d) in the presence of the rubbery copolymer (n), and the constituent components thereof are The composition consists of methi methacrylate/L/80 to 100 weight by weight and other copolymerizable vinyl or vinylidene monomers from 0 to 20 weight. If the amount of methyl methacrylate is less than 80% by weight, the resulting methacrylic resin composition tends to have poor heat resistance. Other copolymerizable vinyl or vinylidene monomers include methyl acrylate and butylacrylate.
, acrylic acid alkyl esters having 1 to 8 carbon atoms such as 2-ethylhexyl acrylate μ, styrene, acrylonitrile, and the like. Furthermore, the above-mentioned carbon 2
Crosslinkable monomers having two or more heavy bonds can also be used. The amount of monomer mixture used is rubbery copolymer (II
) 20 to 200 parts by weight per 100 parts by weight,
If it is less than 20 parts by weight, impact resistance and surface gloss will be poor.
If it exceeds 200 parts by weight, the multi-structure graft copolymer (■
) productivity tends to decline.

Furthermore, it is also possible to add a polymerization degree regulator such as mercaptans during the polymerization of the monomer mixture (d). Examples of mercaptans include various alkyl mercaptans, thioglyco-acid and its esters, β-me-captopropionic acid and its esters, thiopheno-μ, thiocresol, and the like.

As a method for producing the multilayer graft copolymer Cm> of the present invention, an emulsion polymerization method is particularly preferred.

Hereinafter, a production example using the emulsion polymerization method will be explained.

First, after adding deionized water and an emulsifier if necessary into a reaction vessel, the monomer mixture (c) constituting the rubbery copolymer (n) is added and polymerized, and then the rubbery copolymer (
In the presence of If), the monomer mixture (d) of @shi is added to carry out polymerization.

Polymerization temperature is 30-120°C, preferably 50-100°C
It is. The polymerization time varies depending on the type and amount of the polymerization initiator and emulsifier used and the polymerization temperature, but is usually (L5 to 15 hours).

The ratio of polymerizable component to water is polymerizable component/water%, /20 to 1.
A range of /1 is preferred.

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

The method of charging each monomer in each polymerization stage is the batch charging method,
Alternatively, a split preparation method can be used.

The emulsifier is not particularly limited as long as it is a commonly used emulsifier, and examples thereof include long-chain alkyl carboxylates, cyano-kyle sulfosuccinic acid salts, alkylbenzene sulfonates, and the like.

The type of polymerization initiator is not particularly limited, and for example, inorganic initiators such as water-soluble persulfates and perborates are used alone or in combination with sulfites, thiosulfates, etc. as redox initiators. You can also do that. Also, redox initiation systems such as organic hydroperoxide-ferrous salts, organic hydroperoxide V dosodium sulfoxylates,
Initiators such as benzoyl peroxide and azobisisobutyronitrile can also be used.

Multi-structure graft copolymer obtained by emulsion polymerization method (
III) is obtained as a powdery polymer by coagulating, recovering, washing and drying a polymer latex by a known method.

The multi-structure graft copolymer (I) obtained as described above
II) is blended with the methacrylic resin (I) to form the methacrylic resin composition of the present invention. In addition, in the methacrylic resin composition, the rubbery copolymer (n) component of the multilayer graft copolymer (m) is (L1
It is necessary that the content is ~50% by weight, and if it is less than α1% by weight, the effect of solvent resistance and impact resistance will be poor.
On the other hand, if it exceeds 50% by weight, heat resistance tends to be poor.

Methacrylic resin CI) and multi-structure graft copolymer (m
) is preferably blended by melt mixing. Prior to melt mixing, add stabilizers, lubricants, softeners, etc., if necessary.
After blending coloring agents, fillers, etc. using a V-type tumbler or Henschel mixer, it is mixed using a mixing glow, screw type extruder, etc.
Melt mixing can be performed at 50°C.

[Example] Hereinafter, the present invention will be explained in more detail with reference to Examples. In the examples, "parts" and "-" represent "parts by weight" and "% by weight," respectively.

Examples 1-5, Comparative Examples 1-2, Reference Example (1) Production of multi-structure graft copolymer (III) (1)
%,) Production of Rubbery Copolymer (II)Into a stainless steel reaction vessel with an internal volume of SOZ, the raw materials for the manure (1) and the raw materials for (11) shown in Table 1 were placed in various proportions, and the mixture was stirred. After blowing nitrogen gas into the room to make it virtually unaffected by oxygen,
The temperature was raised to 65°C, and the following CIll) raw materials were added.
The temperature was further raised to 80°C and polymerization was continued for 90 minutes. After that, 9 pieces of raw material 1015YU with the same composition as shown in (11) were added.
The polymerization was continued for 120 minutes to obtain a rubbery copolymer (n) in the form of a latex.

(1) Raw material methano-N soog boric acid
100g sodium carbonate
10g (IH) Raw material deionized water 500g Lysium formaldehyde phoxylate 509 jar 1) N-Aeta-SeV phosphate (Nikko Chemicals Co., Ltd. product) The particle size of the obtained latex is determined by the absorbance. As a result of measurement according to the method, it was 115 μm.

(1-2) Production of multi-structure graft copolymer d■) Next, the obtained rubbery copolymer (II) 10 kP (
A reaction vessel containing latex containing 100 parts of
Deionized water (SOOG 8-LN 259 ) was added while stirring while maintaining the temperature at °C, and the following raw material (IV) (60 parts) was further added continuously over 90 minutes for polymerization.

Thereafter, polymerization was continued for another 60 minutes to obtain a multilayer graft copolymer (m) in the form of latex.

Methyl methacrylate (MMA) (96)
57609 Acrylic acid ethyl/I/(g people) (4-)
zao9 normal octyl mercaptan (n-
C, SR) 159 cumene hydroperoxide (cHP) 18 g This latex was coagulated, washed and dried by the method described below.

Pour 50 kg of 1.0% sulfuric acid water into a stainless steel container, raise the temperature to 85°C while stirring, and mix the latex 2 prepared earlier.
9 was continuously added to 5 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 separated and washed with deionized water to obtain a white creamy polymer, which was dried at 70°C for 36 hours to obtain a white powdery polymer. .

(2) Production of methacrylic resin (I) As methacrylic resin (I), methacrylic acid methacrylate μ/methacrylic acid methacrylate
A bead-shaped copolymer having a ratio of 99/1 and a reduced viscosity of 1060 (A/g) in chloroform was produced by a known suspension polymerization method.

(3) Production of Metac VtV resin composition (1) above,
The methacrylic resin CI) obtained in (2) and the multi-structure graft copolymer (m) are shown in Table 2, and the proportions are 10 kg,
and triphenylphosphite 309 with an internal volume of 20
1 super mixer (manufactured by Tsukihi Seisakusho Co., Ltd., 8MV-
20 type) and blended for 5 minutes at a stirring speed of 180 rpm.

The obtained pressed product was transferred to a screw extruder with an outer diameter of 40 mφ (P-40-26AB-V manufactured by Nippon Steel Co., Ltd.).
mold, L/D-26), V cylinder temperature 200~
After melt-kneading to form pellets at 260°C and a die temperature of 250°C, the test pieces obtained by injection molding under the following conditions were evaluated, and the results shown in Table 2 were obtained.

Injection molding machine: Nippon Steel Shinsei Co., Ltd., V%, 7-65 type screw complete set automatic injection molding machine Injection molding conditions: V cylinder temperature 230-260°C, mold temperature 55°C Examples 6-8 Examples An experiment was carried out in the same manner as in Example 1, except that the multi-structure graft copolymer Cm) used in Example 1 was manufactured by the method described below. The results are shown in Table 4.

(1) Production of rubbery copolymer (n) First, the following raw materials (1) were placed in a stainless steel reaction vessel with an internal volume of 50 tons, and nitrogen gas was blown into the container while stirring to create a state substantially free from the influence of oxygen. Thereafter, the temperature was raised to 70°C, the following raw materials (1) were added, and polymerization was carried out for 2 hours to obtain a latex of a hard crosslinked resin body.

(1) Raw material deionized water 20 to 9S-LN
16g boric acid
sag carbonated soda
81MMA C97%)
1vaa9HA (1%)
2091.3-butylene dimethacrylate (2%)
4090) Raw material deionized water 500g Potassium persulfate (KPS) 249 Into the above container containing the hard crosslinked resin latex in an amount equivalent to 2 to 9 (20 parts) of the solid content after the above polymerization has substantially completed. ,the below described(
After adding the raw material (IV) and raising the temperature to 80°C, the raw material (IV) shown in Table 3 (80 parts) was added continuously over 150 minutes, and after the addition was completed, polymerization was continued for an additional 180 minutes to form a hard material. A rubbery copolymer (II) containing a resin component inside the particles was obtained in the form of a latex. As a result of measuring the particle size of the obtained latex by an absorbance method, it was found to be 128
It was a μ wing.

(lit) Raw material deionized water 500g Methanol-A
/ soogB-LN
509 Sodium phopolymer μdehyde spoxy V-) 529(2) Production of multi-structure graft copolymer (I After adding and stirring the raw material (V) below into the above container, the raw material (vl) below was continuously added over 150 minutes. Thereafter, polymerization was continued for an additional hour to obtain a multilayer graft copolymer (Ill) in the form of a latex.

(V) Raw material deionized water soogB-LN
20g (vl) Raw material MMA (96chi) 4800gHA
(4%) 1009n-C,8H
12,5Jil tertiary butyl hydroxy peroxide
5I The obtained latex was coagulated, washed, and dried in the same manner as in Example 1 to obtain a multilayer graft copolymer (■).
After obtaining the powder, it was mixed with methacrylic resin BvJ (I) at the ratio shown in Table 4 and evaluated.

Table 3 ■ *1) is as described above.

〔Effect of the invention〕

As described above, the methacrylic resin composition of the present invention has excellent impact resistance and solvent resistance in the low temperature range and room temperature range, and therefore has excellent industrial effects.

Claims (1)

[Scope of Claims] 1) A methacrylic resin (I) obtained by polymerizing methyl methacrylate alone or a mixture of methyl methacrylate and other copolymerizable vinyl or vinylidene monomers, and an alkyl group. At least one monomer selected from acrylic acid alkyl esters having 1 to 8 carbon atoms (a) 74.9 to 84.9% by weight, selected from styrene and vinyltoluene having a polymerizable functional group at one end 15 to 25% by weight of a macromer (b) consisting of at least one type of carbon-carbon double bond, 0.1 to 5% by weight of a crosslinkable monomer having two or more carbon-carbon double bonds, and other copolymerizable vinyl or vinylidene. A monomer mixture (c
) in the presence of 100 parts by weight of rubbery copolymer (II), 80 to 100% by weight of methyl methacrylate.
and other copolymerizable vinyl or vinylidene monomers 0~
A multilayer structure graft copolymer obtained by polymerizing 20 to 200 parts by weight of a monomer mixture (d) consisting of 20% by weight (
III), wherein the rubbery copolymer (II) component of the multi-structure graft copolymer (III) is 0 in the entire composition.
．． A methacrylic resin composition containing 1 to 50% by weight. 2) The methacrylic resin composition according to claim 1, wherein the polymerizable functional group at one end of the macromer (b) is a (meth)acryloyloxy group. 3) A methacrylic resin (I) obtained by polymerizing methyl methacrylate alone or a mixture of methyl methacrylate and other copolymerizable vinyl or vinylidene monomers, and a rubbery copolymer (II). Made by polymerizing a monomer mixture consisting of 80 to 100% by weight of methyl methacrylate and 0 to 20% by weight of other copolymerizable vinyl or vinylidene monomers in a range of up to 50% by weight based on the total weight. At least one selected from acrylic acid alkyl esters containing a hard resin component inside the particles and having an alkyl group having 1 to 8 carbon atoms.
Macromer (b) consisting of 74.9 to 84.9% by weight of seed monomer (a) and at least one selected from styrene and vinyltoluene having a polymerizable functional group at one end 15
~25% by weight, 0.1 to 5% by weight of a crosslinking monomer having two or more carbon-carbon double bonds, and 0 to 20% by weight of other copolymerizable vinyl or vinyl monomers. In the presence of 100 parts by weight of rubbery copolymer (II) obtained by copolymerizing polymer mixture (c), 80 to 100 parts by weight of methyl methacrylate and other copolymerizable vinyl or vinylidene monomers. A composition consisting of a multi-structured graft copolymer (III) obtained by polymerizing 20-200 parts by weight of a monomer mixture (d) of 0 to 20% by weight, wherein the multi-structure graft copolymer (III) is obtained by polymerizing 20 to 200 parts by weight of a monomer mixture (d) of 0 to 20% by weight, wherein the multistructured graft copolymer (III) is The rubbery copolymer (II) component of the graft copolymer (III) is 0.
．． A methacrylic resin composition containing 11 to 50% by weight. 4) The methacrylic resin composition according to claim 3, wherein the polymerizable functional group at one end of the macromer (b) is a (meth)acryloyloxy group.