JPH1072543A - Impact-resistant methacrylic resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a composition excellent in moldability and processability by using a mixture comprising a specified multilayer structure polymer and a specified two-layered structure polymer. SOLUTION: This composition is obtained by mixing a multilayer structure polymer comprising a combination of a flexible polymer layer obtained by emulsion-polymerizing a 1-8C alkyl acrylate (A) with a polyfunctional cross- linking and/or grafting monomer (e.g. allyl methacrylate) in a specified ratio and/or obtained by emulsion-polymerizing a conjugated diolefin with a rigid polymer layer obtained by emulsion-polymerizing a 1-4C alkyl methacrylate (B) and having a rigid polymer layer prepared by emulsion-polymerizing component B as the outermost layer with a two-layered structure polymer composed of an inner layer prepared by emulsion-polymerizing a mixture containing components A and B in a specified ratio in the presence of a specified amount of a chain transfer agent and an outer layer prepared by emulsion-polymerizing component B in the presence of a specified amount of a chain transfer agent in a specified mixing ratio and optionally mixing the resulting mixture with a rigid thermoplastic polymer and a methacrylic resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an impact-resistant methacrylic resin composition excellent in injection moldability, sheet moldability and processability.

[0002]

2. Description of the Related Art Methacrylic resin is excellent in transparency, has a beautiful appearance and weather resistance, and is easy to mold. Therefore, electric parts such as louvers, tail lamps, lenses, tableware, vehicle parts, optical parts, Although widely used for decorative articles, miscellaneous goods, signboards, etc., the strength against impact is not always sufficient, and many improvements and modifications thereof have been studied and commercialized as impact-resistant methacrylic resins. However, although commercially available impact-resistant methacrylic resins satisfy the intended impact resistance to some extent, the impact-resistant multi-layered polymer fine particles are not completely compatible with the surrounding molten resin phase. Injection molding may cause surface defects such as cloud on the gate part of the molded product, depending on the molding conditions, mold gate shape, etc. In processing, unevenness of plate thickness or surface roughness may occur.

[0003]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above problems and to provide an impact-resistant methacrylic resin composition excellent in moldability and workability.

[0004]

The present inventors have conducted intensive studies on impact-resistant methacrylic resins having excellent injection moldability, sheet moldability, workability, and the like. The inventors have found that the above object of the present invention can be solved by obtaining a polymer mixture composed of a plastic polymer and a two-layer structure polymer, and then mixing the polymer mixture with a methacrylic resin, thereby completing the present invention.

[0005] That is, according to the present invention, the above-mentioned object is achieved by 30 to 99% by weight of a multilayer polymer [1] shown below,
Polymer mixture 1 consisting of 0 to 69% by weight of hard thermoplastic polymer [2] and 1 to 20% by weight of two-layer polymer [3]
It can be achieved by an impact-resistant methacrylic resin composition comprising 00 parts by weight and 0 to 900 parts by weight of a methacrylic resin.

Multilayer polymer [1]: 50 to 99.9% by weight of at least one alkyl acrylate having 1 to 8 carbon atoms in an alkyl group, a polyfunctional crosslinkable monomer and / or
Or a soft polymer obtained by emulsion polymerization of a monomer mixture comprising 0.1 to 5% by weight of a polyfunctional graft monomer and 0 to 49.9% by weight of another unsaturated monomer copolymerizable therewith. 20 to 100% by weight of a layer and a conjugated diolefin, 0 to 80% by weight of at least one alkyl acrylate having an alkyl group having 1 to 8 carbon atoms, a polyfunctional crosslinkable monomer and / or a polyfunctional graft monomer 0 to 5% by weight of a body and 0 to 50% by weight of another unsaturated monomer copolymerizable therewith
At least one soft polymer layer selected from soft polymer layers obtained by emulsion polymerization of a monomer mixture comprising: and 50 to 100 weight parts of at least one alkyl methacrylate having 1 to 4 carbon atoms in the alkyl group. %, A polyfunctional crosslinking monomer and / or a polyfunctional graft monomer 0 to 5% by weight,
And other unsaturated monomers copolymerizable therewith.
At least one alkyl methacrylate having an alkyl group having 1 to 4 carbon atoms, wherein the outermost layer is a combination of at least one hard polymer layer obtained by emulsion polymerization of a monomer mixture consisting of 100% by weight. To 100% by weight and 50 to 0% by weight of another unsaturated monomer copolymerizable therewith
A multilayer polymer comprising a hard polymer layer obtained by emulsion polymerization of

Hard thermoplastic polymer [2]: 50 to 100% by weight of at least one alkyl methacrylate having an alkyl group having 1 to 4 carbon atoms and 50 to 50% of another unsaturated monomer copolymerizable therewith. A hard thermoplastic polymer obtained by emulsion polymerization of a monomer mixture consisting of 0% by weight.

Two-layer polymer [3]: 40 to 90% by weight of at least one alkyl methacrylate having an alkyl group having 1 to 4 carbon atoms and at least one alkyl methacrylate having an alkyl group having 1 to 8 carbon atoms. Alkyl acrylate 10-60
% To a monomer mixture consisting of 0 to 20% by weight of another unsaturated monomer copolymerizable therewith, and further 0.1 to 2% by weight of a chain transfer agent based on the total amount of these monomers is added. 10 to 50% by weight of an inner layer obtained by emulsion polymerization, 80 to 100% by weight of at least one alkyl methacrylate having 1 to 4 carbon atoms in an alkyl group, and 1 to 100% by weight of an alkyl group.
At least one alkyl acrylate that is
To a monomer mixture consisting of 20% by weight and 0 to 20% by weight of another unsaturated monomer copolymerizable therewith, a chain transfer agent of less than 0.1% by weight based on the total amount thereof is added and emulsified. A two-layer polymer comprising 90 to 50% by weight of an outer layer obtained by polymerization.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. The multilayer polymer [1] used in the present invention comprises at least one soft polymer layer and at least one hard polymer layer, and the outermost layer is a hard polymer layer. The soft polymer layer in the multilayer polymer has at least one alkyl acrylate having an alkyl group having 1 to 8 carbon atoms of 50 to 99.000 from the viewpoint of impact resistance and the like.
9% by weight, 0.1 to 5% by weight of a polyfunctional crosslinking monomer and / or a polyfunctional graft monomer and 0 to 49.9% by weight of another unsaturated monomer copolymerizable therewith. The monomer mixture is obtained by emulsion polymerization, or the conjugated diolefin is 20 to 100% by weight, and the alkyl group has 1 to 8 carbon atoms.
At least one alkyl acrylate from 0 to 80
% Of a polyfunctional crosslinkable monomer and / or 0 to 5% by weight of a polyfunctional graft monomer and 0 to 50% by weight of another unsaturated monomer copolymerizable therewith. It can be obtained by emulsion polymerization. Further, from the viewpoint of transparency and weather resistance, the hard polymer layer in the multilayer structure polymer is 50 to 100% by weight of at least one alkyl methacrylate having an alkyl group of 1 to 4 and a polyfunctional crosslinkable monomer. 0 to 5% by weight of a monomer and / or a polyfunctional graft monomer, and 0% of another unsaturated monomer copolymerizable therewith.
It can be obtained by emulsion polymerization of a monomer mixture consisting of ５０50% by weight.

Examples of the alkyl acrylate used for the flexible polymer layer include methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, and benzyl acrylate. These may be used alone or in combination of two or more. Examples of the conjugated diolefin include 1,3-butadiene, 2,3-butadiene, isoprene, and chloroprene, and one or more of these can be used. Examples of the alkyl methacrylate used for the hard polymer layer include methyl methacrylate, ethyl methacrylate, and butyl methacrylate, and it is preferable to use methyl methacrylate.

Examples of the polyfunctional crosslinking monomer include ethylene glycol di (meth) acrylate (meaning ethylene glycol diacrylate and ethylene glycol dimethacrylate; the same applies hereinafter), 1,3-butylene glycol di ( (Meth) acrylate, polyethylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, divinylbenzene and the like. Polyfunctional graft monomers include allyl methacrylate, allyl acrylate, allyl maleate , Allyl fumarate, diallyl fumarate, triallyl cyanurate and the like, but are not limited thereto. These may be used alone or in combination of two or more.

The other copolymerizable unsaturated monomer is not particularly restricted but includes, for example, 1,3-butadiene, 2,3-butadiene and 2,3-butadiene.
Diene compounds such as butadiene and isoprene; vinyl aromatic compounds such as styrene, α-methylstyrene and vinyltoluene; acrylates such as methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate and benzyl acrylate (However, excluding the case of the soft polymer layer); methacrylates such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, and benzyl methacrylate (but excluding the case of the hard polymer layer), acrylonitrile, methacrylonitrile, etc. And the like. These may be used alone or in combination of two or more.

The outermost layer of the multi-layered polymer needs to be composed of a hard polymer layer in view of compatibility with methacrylic resin and the like. Is 10% by weight or more, preferably 20 to 5%.
It is desirably 0% by weight. From the viewpoints of transparency and weather resistance, the monomer constituting the outermost layer is composed of at least one alkyl methacrylate having an alkyl group having 1 to 4 carbon atoms in an amount of 50 to 100% by weight and another copolymerizable with the alkyl methacrylate. A monomer mixture consisting of 50 to 0% by weight of unsaturated monomer. As the alkyl methacrylate and other copolymerizable unsaturated monomers, those mentioned above can be used. Further, when polymerizing the monomer constituting the outermost layer, it is possible to add a chain transfer agent such as n-octyl mercaptan or n-dodecyl mercaptan from the viewpoint of compatibility with the methacrylic resin to be melt-kneaded. desirable.

As a method for producing the above-mentioned multilayer structure polymer,
For example, a method in which a monomer mixture for each layer is successively emulsion-polymerized to obtain a polymer latex is preferably employed. The multilayer structure polymer thus obtained is
It plays a role of imparting impact resistance, and can have a polymer layer structure of, for example, soft / hard, hard / soft / hard, soft / hard / hard, and the particle size is usually 0.05 to 0.
5 μm.

The rigid thermoplastic polymer [2] used in the present invention is used in combination with the above-mentioned multilayer-structured polymer in order to uniformly disperse the multilayer-structured polymer particles, prevent occurrence of dust, etc., and improve the surface appearance. Is preferred. From the viewpoint of transparency and weather resistance, the monomer constituting the rigid thermoplastic polymer is mixed with 50 to 100% by weight of at least one alkyl methacrylate having an alkyl group having 1 to 4 carbon atoms, and It is a monomer mixture comprising 50 to 0% by weight of another polymerizable unsaturated monomer. As the alkyl methacrylate and the other copolymerizable unsaturated monomer, the monomers mentioned in the above-mentioned multilayer polymer can be used. As the alkyl methacrylate, methyl methacrylate is particularly preferably used. In the polymerization of the hard thermoplastic polymer, it is preferable to add a chain transfer agent such as n-octyl mercaptan or n-dodecyl mercaptan from the viewpoint of compatibility with the multilayer structure polymer and the methacrylic resin. As the weight average molecular weight of the plastic polymer,
Although slightly different depending on the composition of the hard thermoplastic polymer, 7
It is preferably in the range of from 000 to 200,000.

The hard thermoplastic polymer can be obtained as a polymer latex by emulsion-polymerizing the above monomer mixture. The particle size of the hard thermoplastic polymer is not particularly limited, but is preferably 0.05 to 0.3 μm, and more preferably smaller than the particle size of the multilayer structure polymer. The addition amount of the hard thermoplastic polymer is 0 to 69% by weight, preferably 10 to 50% by weight, and if it exceeds 69% by weight, it is not preferable in terms of productivity.

Further, the two-layered polymer [3] used in the present invention is entangled with the above-mentioned rigid thermoplastic polymer and a matrix resin which forms a molten phase such as a methacrylic resin to be described later to change and control the flow behavior. Since it can exert the effect of causing the mixture to flow, it is composed of a combination of an inner layer that starts flowing at a lower temperature and an outer layer that forms stronger entanglement. That is, the two-layer polymer has at least one alkyl methacrylate having an alkyl group of 1 to 4 carbon atoms of 40 to 9;
0% by weight, 10 to 60% by weight of at least one alkyl acrylate having an alkyl group having 1 to 8 carbon atoms, and 0 to 20% by weight of another unsaturated monomer copolymerizable therewith. 0.1 to 2% by weight, preferably 0.1 to 1% by weight, more preferably 0.2 to 1% by weight of a chain transfer agent is added to the body mixture, and emulsion polymerization is carried out. 10 to 50% by weight of the inner layer, 80 to 100% by weight of at least one type of alkyl methacrylate having 1 to 4 carbon atoms in the alkyl group, and 1 to 100% by weight of carbon atoms in the alkyl group.
At least one alkyl acrylate from 0 to 2
0% by weight and 0 to 20% by weight of other unsaturated monomers copolymerizable therewith, in a monomer mixture of less than 0.1% by weight, preferably 0 to 0. 05
Outer layer 90-% by weight of a chain transfer agent and emulsion polymerization
10% by weight. As the alkyl methacrylate, alkyl acrylate and other copolymerizable unsaturated monomers, the monomers mentioned in the above-mentioned multilayer structure polymer can be used, and as the alkyl methacrylate, methyl methacrylate is particularly preferable. . The chain transfer agent is not particularly limited, but n-octyl mercaptan, n-dodecyl mercaptan and the like are preferably used.

The inner layer of the two-layer polymer preferably has better fluidity than the hard thermoplastic polymer and / or methacrylic resin used and has a weight average molecular weight of 4
0000-150,000, preferably 50,000-
It is desirable that the temperature is in the range of 100,000 and the Tg is 0 ° C. or higher, preferably 25 to 75 ° C. The weight ratio of the inner layer is 10 to 50% by weight, preferably 20 to 45% by weight of the polymer having a two-layer structure, since it plays an auxiliary role of the outer layer. On the other hand, the outer layer is composed of a hard thermoplastic polymer and / or
Or from the role of forming a better entanglement with the methacrylic resin and imparting excellent injection moldability, sheet workability, etc., it is necessary to flow but have a higher molecular weight than the inner layer, and the amount of chain transfer agent is Less than 0.1% by weight;
The weight average molecular weight is 300,000 or more, preferably 50
In the range of 0000 to 2,000,000 and Tg of 7
It is desirable that the temperature be 5 ° C. or higher, preferably 80 to 110 ° C. The particle diameter of the two-layer polymer used in the present invention is not particularly limited, but is preferably 0.05 to 0.3 μm, and more preferably smaller than the particle diameter of the multilayer polymer. The addition amount of the two-layer polymer is 1 to
The content is 20% by weight, preferably 2 to 8% by weight, and if it exceeds 20% by weight, the fluidity decreases, which is not preferred.

The emulsion polymerization method for obtaining the multilayer structure polymer, the rigid thermoplastic polymer and the two-layer structure polymer of the present invention is not particularly limited, and a known method can be used. The type and amount of the emulsifier used in the emulsion polymerization are selected depending on the stability of the polymerization system, the intended particle size, and the like, but known emulsifiers such as anionic surfactants, cationic surfactants, and nonionic surfactants are used. One or more kinds can be used, and an anionic surfactant is particularly preferably used. The polymerization initiator used for the emulsion polymerization is not particularly limited, and a persulfate-based or redox-based initiator is used. A chain transfer agent such as an alkyl mercaptan is used as needed. In emulsion polymerization, a monomer, an emulsifier, a polymerization initiator, a chain transfer agent, and the like are added by any method such as a batch addition method, a division addition method, and a continuous addition method. The method for precipitating and coagulating the polymer latex obtained by emulsion polymerization is not particularly limited, and a salting out method,
Acid precipitation, spraying, freezing and the like are possible.

The polymer mixture used in the present invention contains 30 to 99% by weight, preferably 42 to 9% by weight of the multilayer polymer [1].
8% by weight, 0 to 69% by weight of rigid thermoplastic polymer [2]
And the amount of the two-layer polymer [3] is 1 to 20% by weight, and it can be usually obtained by mixing the obtained polymer after precipitation and coagulation of each latex of the above polymer and drying. Alternatively, these polymer latexes can be obtained by uniformly mixing in a latex state, then coagulating and separating by an arbitrary coagulation method and drying.

The impact-resistant methacrylic resin composition of the present invention comprises a mixture of 100 parts by weight of the above polymer mixture and 0 to 900 parts by weight, preferably 20 to 400 parts by weight of a methacrylic resin. Or in a state where these are melt-mixed to form pellets or the like. The obtained impact-resistant methacrylic resin composition can be used as a molding material for injection molding or the like and processed as it is into a sheet and a film by an extruder.
The methacrylic resin is not particularly limited as long as it can be melt-mixed with the polymer mixture, and is a commercially available hard methacrylic resin mainly composed of methyl methacrylate and containing a small amount of methyl acrylate or the like. Bead-shaped or pellet-shaped molding materials are preferably used. Hard methacrylic resin is usually methyl methacrylate
And a copolymer monomer unit such as methyl acrylate and ethyl acrylate of 20% by weight or less, and has a weight average molecular weight of about 70,000 to 300,000. The impact-resistant methacrylic resin composition of the present invention can contain an ultraviolet absorber, an antioxidant, a lubricant, a dye, a pigment and the like usually used for methacrylic resins within a range that does not hinder the purpose of the present invention.

[0022]

EXAMPLES Next, the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples.
In the examples, “%” and “parts” are “% by weight”.
And "parts by weight", and the monomers, polymerization initiators, chain transfer agents and the like used are represented by the following abbreviations. Methyl methacrylate: MMA Methyl acrylate: MA Ethyl acrylate: EA n-butyl acrylate: BA Styrene: ST Butadiene: BD Allyl methacrylate: ALMA 1,3-butylene glycol dimethacrylate: BGDMA n-octyl mercaptan: n-OM

The physical properties of the resin composition and the like were measured and evaluated according to the following methods. (1) Particle size The obtained latex is diluted with pure water to 0.1 to 0.2%
The resulting solution was put into an aluminum tray so as to have a thickness of about 1 mm, dried at 80 ° C., and dried with a scanning electron microscope [Model JSM-6300 manufactured by JEOL Ltd.]
F], and the particle diameter was measured. (2) Molecular weight Using chloroform as a solvent, the intrinsic viscosity at 25 ° C. was measured and calculated.

(3) Glass transition temperature: determined by the equation of Tg Fox. In addition, Tg of each monomer is described in Polymer Handbook / Wiley intersiece.
The value of nce was used. (4) Izod impact strength (with notch) Measured in accordance with ASTM-D256. (5) Heat deformation temperature: Measured according to HDT ASTM-D648 (264 psi). (6) Total light transmittance, haze Measured according to ASTM-D1003 (5 mm thickness).

<Evaluation of moldability> The moldability and processability of the resin composition were determined by pelletizing the resin composition and measuring 3 m with an injection molding machine.
The evaluation was performed by molding a m-mirror flat plate and by manufacturing a 3 mm extruded plate with a 90φ sheet extruder equipped with three mirror-finished rolls, and then heating and pushing up the extruded plate.

Example 1 (1) Production of Multilayered Polymer (A-1) Latex 150 parts of ion-exchanged water was placed in a reactor equipped with a reflux condenser.
0.3 parts of sodium stearate and 0.05 parts of sodium lauryl sarcosinate were charged and heated to 80 ° C. while stirring under a nitrogen atmosphere, and then 24 parts of MMA, 1 part of EA, A
A monomer mixture consisting of 0.05 parts LMA, and 1% K
Charge 2.5 parts of PS (potassium persulfate) aqueous solution
The polymerization was completed by reacting for 1 minute. Subsequently, after charging 5 parts of a 1% KPS aqueous solution, 41.3 parts of BA and ST8.7 were added.
Parts and 1 part of ALMA were dropped continuously for 60 minutes, and the whole amount was charged. After that, the mixture was held for 60 minutes to complete the polymerization. Then, after charging 2.5 parts of 1% KPS aqueous solution,
A monomer mixture consisting of 24 parts of MMA, 1 part of MA, and 0.05 part of n-OM was continuously dropped in its entirety over 40 minutes, and after dropping, the polymerization was completed by holding for 60 minutes to complete the multilayer structure polymer (A
-1) A latex was obtained. After the polymerization of each layer was completed, the latex was sampled, and it was confirmed by electron microscopic observation that no new particles were generated and that the sequential polymerization was performed. The particle size of the obtained latex was 0.24 μm. The composition of this latex is shown in Table 1 (A-1).

(2) Production of Rigid Thermoplastic Polymer (B-1) Latex 150 parts of ion-exchanged water was placed in a reaction vessel equipped with a reflux condenser.
1.2 parts of sodium stearate and 0.5 parts of sodium lauryl sarcosinate were charged, and heated to 75 ° C. while stirring under a nitrogen atmosphere, and then 47 parts of MMA, 3 parts of MA, and n-
A monomer mixture consisting of 0.13 parts of OM, and 1% KP
5 parts of an aqueous S solution was charged and reacted for 60 minutes to complete the polymerization. Subsequently, after charging 5 parts of a 1% KPS aqueous solution, M
A monomer mixture consisting of 47 parts of MA, 3 parts of MA, and 0.13 part of n-OM was continuously dropped for 60 minutes, and the whole amount was charged.
Hold for 0 minutes to complete the polymerization. The particle size of the obtained latex was 0.12 μm. The composition of this latex is shown in Table 1 (B-1).

(3) Production of latex polymer (C-1) latex 150 parts of ion-exchanged water was placed in a reaction vessel equipped with a reflux condenser.
After charging 1.2 parts of sodium stearate and 0.5 parts of sodium lauryl sarcosinate, the mixture was heated to 75 ° C. while stirring under a nitrogen atmosphere, and then 15 parts of MMA, 10 parts of EA, n
A monomer mixture consisting of 0.12 parts of OM and 1% K
2.5 parts of PS aqueous solution was charged and reacted for 60 minutes to complete the polymerization. Next, when 7.5 parts of a 1% KPS aqueous solution was charged, 75 parts of MMA was continuously added dropwise for 100 minutes, and after charging the whole amount, the mixture was held for 60 minutes to complete the polymerization. The particle size of the obtained latex was 0.14 μm. The composition of this latex is shown in (C-1) of Table 1.

Each polymer latex thus obtained was converted into a polymer having a multilayer structure (A-1)
60 parts, 35 parts of the rigid thermoplastic polymer (B-1) and 5 parts of the two-layered polymer (C-1) are uniformly mixed in a latex state, and then a 2% aqueous magnesium sulfate solution is added to carry out salting out coagulation. After washing with water and drying, a polymer powder was obtained. 100 parts of the obtained polymer powder and parapet EH beads, a hard methacrylic resin [manufactured by Kuraray Co., Ltd .: Extrusion molding grade, hereinafter abbreviated as (D-1). And 100 parts were uniformly mixed, and an extruded plate was manufactured using a sheet extruder, and various physical properties were measured and evaluated. Table 2 shows the results.

Example 2 (1) Production of Multilayered Polymer (A-2) Latex 150 parts of ion-exchanged water was placed in a reactor equipped with a reflux condenser.
After charging 0.2 parts of sodium dioctylsulfosuccinate and heating to 85 ° C. while stirring under a nitrogen atmosphere,
A monomer mixture composed of 33 parts of A, 2 parts of MA, 0.15 part of ALMA, and 3.5 parts of a 1% KPS aqueous solution were charged and reacted for 60 minutes to complete polymerization. Then 1% KPS
After charging 4.5 parts of aqueous solution, 36.5 parts of BA, ST
A monomer mixture consisting of 8.5 parts and 1 part of ALMA was continuously added dropwise for 60 minutes, and the whole amount was charged. Thereafter, the mixture was held for 60 minutes to complete the polymerization. Next, after charging 2 parts of a 1% KPS aqueous solution, a monomer mixture consisting of 19 parts of MMA, 1 part of MA, and 0.05 part of n-OM was continuously dropped over 40 minutes,
After the dropping, the mixture was held for 60 minutes to complete the polymerization, thereby obtaining a multilayer polymer (A-2) latex. After the polymerization of each layer was completed, the latex was sampled, and it was confirmed by electron microscopic observation that no new particles were generated and that the sequential polymerization was performed. The particle size of the obtained latex was 0.16 μm. The composition of the latex is shown in Table 1 (A-2).

(2) Production of Rigid Thermoplastic Polymer (B-2) Latex 150 parts of ion-exchanged water was placed in a reactor equipped with a reflux condenser.
0.6 parts of sodium dioctyl sulfosuccinate was charged, and the temperature was raised to 80 ° C. while stirring under a nitrogen atmosphere.
A18 parts, EA2 parts, n-OM0.05 parts, and 1%
Two parts of the KPS aqueous solution was charged and reacted for 40 minutes to complete the polymerization. Subsequently, when 8 parts of a 1% KPS aqueous solution was charged, a monomer mixture composed of 72 parts of MMA, 8 parts of EA, and 0.2 part of n-OM was continuously dropped for 90 minutes, and the entire amount was charged, followed by polymerization for 60 minutes. Was completed. The particle size of the obtained latex was 0.07 μm. The composition of this latex is shown in Table 1 (B-2).

(3) Production of polymer having two-layer structure (C-2) latex 150 parts of ion-exchanged water was placed in a reaction vessel equipped with a reflux condenser.
0.5 part of sodium dioctylsulfosuccinate was charged and heated to 75 ° C. while stirring under a nitrogen atmosphere.
A monomer mixture consisting of 20 parts of A, 10 parts of EA, 0.2 parts of n-OM, and 3 parts of a 1% KPS aqueous solution were charged and charged to 60 parts.
The polymerization was completed by reacting for 1 minute. Next, when 7 parts of a 1% KPS aqueous solution was charged, 66 parts of MMA, 4 parts of EA, n
A monomer mixture consisting of 0.04 parts of -OM was continuously dropped for 100 minutes, and after the entire amount was charged, the mixture was maintained for 60 minutes to complete the polymerization. The particle size of the obtained latex is 0.12 μm
Met. The composition of this latex and the like are shown in Table 1 under (C-
See 2).

Each of the polymer latexes thus obtained was converted into a polymer having a multilayer structure (A-2).
After uniformly mixing 80 parts, 10 parts of the hard thermoplastic polymer (B-2) and 10 parts of the two-layer polymer (C-2) in a latex state, the mixture was freeze-coagulated at −40 ° C. for 3 hours, and then 75%.
The ice was melted in warm water at ℃, then dehydrated and dried to obtain a polymer powder. 100 parts of the obtained polymer powder and parapet HR-L, a hard methacrylic resin [manufactured by Kuraray Co., Ltd .: grade for injection molding, hereinafter abbreviated as (D-2)]
100 parts were uniformly mixed and pelletized, and injection molding evaluation and various physical properties were evaluated. Table 2 shows the results.

Example 3 (1) Production of Multilayered Polymer (A-3) Latex 140 parts of ion-exchanged water was placed in a reactor equipped with a reflux condenser.
After charging 1 part of sodium lauryl sarcosinate and purging with nitrogen, 30 parts of BA, 0.15 part of cumene hydroperoxide, 0.4 part of sodium pyrophosphate, 0.005 part of ferrous sulfate, and 0.2 part of dextrose Department and BD
20 parts were charged, the temperature was increased to 70 ° C. under pressure, and polymerization was performed for 2 hours. Next, the obtained latex was cooled to 55 ° C., and 1%
After charging 5 parts of KPS aqueous solution, 48 parts of MMA, MA2
Parts and 0.1 part of n-OM were continuously added dropwise over 60 minutes, and after the addition, the mixture was maintained for 60 minutes to complete the polymerization to obtain a multilayer polymer (A-3) latex.
After the polymerization of each layer was completed, the latex was sampled, and it was confirmed by electron microscopic observation that no new particles were generated and that the sequential polymerization was performed. The particle size of the obtained latex was 0.08 μm. The composition of this latex,
This is shown in (A-3) of Table 1.

(2) Production of rigid thermoplastic polymer (B-3) latex 150 parts of ion-exchanged water was placed in a reaction vessel equipped with a reflux condenser.
0.6 parts of sodium dioctyl sulfosuccinate was charged, and the temperature was raised to 80 ° C. while stirring under a nitrogen atmosphere.
A39 parts, EA1 part, n-OM 0.16 part, and 1%
Two parts of the KPS aqueous solution was charged and reacted for 40 minutes to complete the polymerization. Subsequently, when 8 parts of a 1% KPS aqueous solution was charged, 58.5 parts of MMA, 1.5 parts of EA, and 0.2 parts of n-OM 0.2
The monomer mixture consisting of 4 parts was dropped continuously for 90 minutes, and the whole amount was charged. After that, the mixture was held for 60 minutes to complete the polymerization. The particle size of the obtained latex was 0.18 μm. The composition of this latex is shown in Table 1 (B-3).

(3) Production of latex polymer having two layers (C-3) 150 parts of ion-exchanged water was placed in a reaction vessel equipped with a reflux condenser.
0.5 part of sodium dioctylsulfosuccinate was charged and heated to 75 ° C. while stirring under a nitrogen atmosphere.
A monomer mixture consisting of 15 parts of A, 10 parts of BA, and 0.1 part of n-OM, and 3 parts of a 1% KPS aqueous solution were charged, and 60 parts were charged.
The polymerization was completed by reacting for 1 minute. Next, when 7 parts of a 1% KPS aqueous solution was charged, 75 parts of MMA and n-OM0.
A monomer mixture consisting of 01 parts was continuously dropped for 100 minutes,
After charging the entire amount, the mixture was held for 60 minutes to complete the polymerization.
The particle size of the obtained latex was 0.09 μm.
The composition of this latex is shown in Table 1 (C-3).

Each of the polymer latexes thus obtained was converted into a polymer having a multilayer structure (A-3).
80 parts, 15 parts of the hard thermoplastic polymer (B-3) and 5 parts of the two-layer polymer (C-3) were uniformly mixed in a latex state, and then freeze-coagulated at −40 ° C. for 3 hours to give 75 parts. ° C
Was melted in warm water, followed by dehydration and drying to obtain a polymer powder. 100 parts of the obtained polymer powder and 100 parts of parapet HR-L which is a hard methacrylic resin were uniformly mixed and pelletized, and injection molding evaluation and various physical properties were evaluated. Table 2 shows the results.

Examples 4 to 8 In the same manner as in Example 1, multilayer polymers (A-4) to (A-6) having different numbers of layers, different compositions and different particle sizes, and two-layer polymer ( C-4) A latex was obtained. Table 1 shows the number of layers, composition, particle size, and the like of these polymers. Except that the mixing ratio of each polymer in the latex and emulsion blend and the mixing ratio with the hard methacrylic resin at the time of molding are shown in Table 2, the obtained injection molded flat plate and extruded plate were measured in the same manner as in Example 1. evaluated. The results are shown in Table 2.

Comparative Examples 1 to 3 In each of the examples, the multilayered polymer latex, the hard thermoplastic polymer latex and the two-layered polymer latex were used. If the value deviated from the scope of the claims, the occurrence of defects was found, and satisfactory results could not be obtained. Table 2 shows the results.

[0040]

[Table 1] [In the table, a horizontal line (-) is used to indicate a monomer used to form the same layer, and a hatched line (/) is used to indicate that the layers are different. ]

[0041]

[Table 2]

[0042]

As described above, since the impact-resistant methacrylic resin composition of the present invention is excellent in moldability and processability, it can supply an injection-molded article having a good appearance and can form a film or sheet. In this method, a wide range of extrusion conditions can be obtained, and a product having a high uniformity can be supplied with less deviation of the sheet thickness during sheet processing.

Continued on the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical display location C08F 265/06 MQM C08F 265/06 MQM 285/00 MQX 285/00 MQX

Claims (1)

[Claims] 1. A multilayer polymer [1] 3 shown below:
100 parts by weight of a polymer mixture consisting of 0 to 99% by weight, 0 to 69% by weight of a hard thermoplastic polymer [2] and 1 to 20% by weight of a two-layer polymer [3];
An impact-resistant methacrylic resin composition comprising 900 parts by weight. Multilayer polymer [1]: at least one alkyl acrylate having 1 to 8 carbon atoms in the alkyl group, 50 to 9
9.9% by weight, 0.1 to 5% by weight of a polyfunctional crosslinking monomer and / or a polyfunctional graft monomer and 0 to 49.9% by weight of another unsaturated monomer copolymerizable therewith. A soft polymer layer obtained by emulsion-polymerizing a monomer mixture comprising: 20 to 100% by weight of a conjugated diolefin; 0 to 80% by weight of at least one alkyl acrylate having 1 to 8 carbon atoms in an alkyl group; Emulsion polymerization of a monomer mixture comprising 0 to 5% by weight of a polyfunctional crosslinking monomer and / or a polyfunctional graft monomer and 0 to 50% by weight of another unsaturated monomer copolymerizable therewith. At least one soft polymer layer selected from soft polymer layers comprising: 50 to 100% by weight of at least one alkyl methacrylate having an alkyl group having 1 to 4 carbon atoms; a polyfunctional crosslinkable monomer; /
Or at least one layer of a hard polymer obtained by emulsion polymerization of a monomer mixture comprising 0 to 5% by weight of a polyfunctional graft monomer and 0 to 50% by weight of another unsaturated monomer copolymerizable therewith. And at least one alkyl methacrylate having an alkyl group having 1 to 4 carbon atoms in an amount of 50 to 100% by weight and another unsaturated monomer copolymerizable therewith with 50 to 0%. A multilayer structure polymer which is a hard polymer layer obtained by emulsion polymerization of weight%. Rigid thermoplastic polymer [2]: alkyl group having 1 to 1 carbon atom
At least one alkyl methacrylate 50 which is 4
A hard thermoplastic polymer obtained by emulsion polymerization of a monomer mixture consisting of 100% by weight and 50% by weight of another unsaturated monomer copolymerizable therewith. Two-layer polymer [3]: at least one type of alkyl methacrylate having an alkyl group of 1 to 4 carbon atoms of 40 to 9
0% by weight, 10 to 60% by weight of at least one alkyl acrylate having an alkyl group having 1 to 8 carbon atoms, and 0 to 20% by weight of another unsaturated monomer copolymerizable therewith.
And a chain transfer agent in an amount of 0.1 to 2% by weight based on the total amount thereof, and 10 to 50% by weight of an inner layer obtained by emulsion polymerization.
At least one alkyl methacrylate 80 to
100% by weight, 0 to 20% by weight of at least one alkyl acrylate having 1 to 8 carbon atoms in the alkyl group, and 0 to 20% by weight of another unsaturated monomer copolymerizable therewith. A two-layer polymer comprising an outer layer formed by adding a chain transfer agent in an amount of less than 0.1% by weight to the total amount of the body mixture and emulsion-polymerizing the resulting mixture.