JP2022183689A - Coagulated powder including acrylic cross-linked rubber particle, production method of the same, resin composition, and molded product - Google Patents

Abstract

To provide a coagulated powder including an acrylic cross-linked rubber particle excellent in dispersibility in a matrix resin (base resin), and excellent in impact resistance.SOLUTION: A coagulated powder includes an acrylic cross-linked rubber particle having an inner layer composed of a cross-linked rubber including an acrylic acid ester unit, an outermost layer composed of a thermoplastic resin including a (meth)acrylic acid unit and graft-bonding to the inner layer, and having an average particle size of 0.08-0.3 μm, where the consumed shear energy E necessary for dispersing the acrylic cross-linked rubber particle to monomodality of a dispersed particle size of 1 μm or under is 180 MJ/m3 or less in a 0.1 mass% acetone dispersion of a melt-kneaded composition of the coagulated powder and the (meth)acrylic resin when melt-kneading 60 pts.mass of a (meth)acrylic resin having an MFR at 230°C, 37.3 N of 8±1 g/10 min. and 40 pts. mass of the coagulated powder, as measured by a kneading extrusion molding evaluation testing machine with a consumed shear energy measuring device at 230°C.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a coagulated powder containing acrylic crosslinked rubber particles, a method for producing the same, a resin composition, and a molded product.

Methacrylic resin has excellent transparency, and its moldings have a beautiful appearance and weather resistance. , and is used in a variety of applications, including medical materials. However, a molded product made of methacrylic resin has insufficient impact resistance, and has a problem that cracks and chips are likely to occur when subjected to stress such as dropping, collision, and vibration.

For improving the impact strength of methacrylic resins, a method of adding multilayer structure polymer particles having a rubber component layer inside and a thermoplastic resin component layer as the outermost layer is preferably used. This method is currently the most widely practiced industrially.

However, in conventional methacrylic impact resistant resins in which multi-layer structure polymer particles are blended in methacrylic resins, although the impact resistance is improved, aggregates of particles are formed on the surface of molded articles obtained therefrom. is observed on the surface, and there is a problem that an appearance defect accompanied by unevenness occurs. In Patent Document 1, a multilayer structure polymer obtained by emulsion polymerization and a rigid thermoplastic polymer are uniformly mixed in a latex state, and then solidified and taken out. A production method has been disclosed that has good dispersibility in mixing and can significantly improve the occurrence of lumps. Poor impact resistance to weight. In Patent Document 2, after dispersing a multilayer structure polymer in an organic solvent, an aqueous phase is separated to obtain an aggregate, and an organic solvent is added to the aggregate to obtain a dispersion, which is a polymerizable organic A manufacturing method is disclosed in which the dispersion state of the multilayer structure polymer is improved by mixing with a compound, but the resin that can be added is limited to a polymerizable organic compound having a reactive group such as an epoxy resin.

Patent No. 3145864 WO2005/028546

An object of the present invention is to provide a coagulated powder containing acrylic crosslinked rubber particles excellent in dispersibility in a matrix resin (base resin) and in impact resistance.

In order to achieve the above objects, the present invention provides a coagulated powder containing crosslinked acrylic rubber particles that satisfies the following conditions, a method for producing the same, a resin composition containing the coagulated powder, and a molded article.
[1]
It has an inner layer containing crosslinked rubber containing alkyl acrylate units and an outermost layer made of a thermoplastic resin containing methyl methacrylate units and graft-bonded to the inner layer, wherein the thermoplastic resin of the outermost layer has a glass transition A coagulated powder containing acrylic crosslinked rubber particles having a temperature of 60 to 85° C., a weight average molecular weight of 40,000 to 80,000, and an average particle size of 0.08 to 0.3 μm,
60 parts by mass of methyl methacrylate resin having a melt flow rate of 8±1 g/10 minutes at 230° C. and 37.3 N and 40 parts by mass of the solidified powder were kneaded and extruded using a kneading/extrusion evaluation test apparatus equipped with a shear energy consumption measuring device. , when melt-kneading at a temperature of 230 ° C.,
Until the acrylic crosslinked rubber particles are unimodally dispersed with a dispersed particle diameter of 1 μm or less in a 0.1% by mass acetone dispersion of the melt-kneaded composition of the coagulated powder and the methyl methacrylate resin. A solidified powder whose consumption shear energy E required for the above is 180 MJ/m ³ or less.
[2]
The coagulated powder according to [1], wherein the acrylic crosslinked rubber particles have an average particle size of 0.2 to 0.3 μm.
[3]
a polymerization step of producing a latex containing acrylic crosslinked rubber particles by an emulsion polymerization method;
aggregating step of aggregating the latex at 35-65°C;
The method for producing a coagulated powder according to [1] or [2], further comprising a granulation step of granulating at 100 to 130°C.
[4]
A resin composition comprising the coagulated powder according to [1] or [2] and a matrix resin.
[5]
The resin composition according to [4], wherein the thermoplastic resin is a methacrylic resin.
[6]
A molded article containing the resin composition according to [4] or [5].

According to the present invention, it is possible to provide a coagulated powder containing acrylic crosslinked rubber particles that are excellent in dispersibility in a matrix resin (base resin) such as a thermoplastic resin and have excellent impact resistance.

Figure 2 shows the measurement results of dispersed particle size distribution of solidified powder in acetone.

<Acrylic crosslinked rubber particles>
The acrylic crosslinked rubber particles constituting the coagulated powder of the present invention are particles containing an acrylic crosslinked rubber polymer obtained by an emulsion polymerization method. It is a multi-layered rubber particle containing a crosslinked rubber polymer (Q) in contact with and covered with the outermost layer. The multi-layered rubber particles have, for example, a two-layer structure (QP) in which the core is a crosslinked rubber polymer (Q) and the outer shell (outermost layer) is a thermoplastic polymer (P), and the core is a crosslinked polymer (R). -Inner shell is a crosslinked rubber polymer (Q) -Outer shell (outermost layer) is a three-layer structure (RQP) of a thermoplastic polymer (P), core is a crosslinked rubber polymer (Q) -First A four-layer structure (QRQP) of a crosslinked polymer (R) for the inner shell, a crosslinked rubber polymer (Q) for the second inner shell, and a thermoplastic polymer (P) for the outer shell (outermost layer). and the like.

A layer other than the outermost layer in the acrylic crosslinked rubber particle (hereinafter, the layer other than the outermost layer may be referred to as an “inner layer”; for example, the above Q, R+Q, and Q+R+Q respectively correspond to the inner layer) and the outermost layer The mass ratio of inner layer/outermost layer is preferably 60/40 to 95/5, more preferably 70/30 to 90/10. The ratio of the layer containing the crosslinked rubber polymer (Q) in the inner layer is preferably 20 to 70% by mass, more preferably 30 to 50% by mass.

The average particle size of the acrylic crosslinked rubber particles is 0.08 to 0.3 μm, preferably 0.2 to 0.3 μm. By using acrylic crosslinked rubber particles having an average particle size within such a range, particularly an average particle size of 0.2 to 0.3 μm, it is possible to express toughness with a small amount of compounding. without compromising the rigidity and surface hardness of the The average particle size in the present specification is the average value (volume average particle size) in the volume-based particle size distribution measured by the light scattering method, or the average value of the particle sizes measured from the electron micrograph. .
In one embodiment of the present invention, the thermoplastic resin of the outermost layer has a glass transition temperature of 60-85°C, preferably 65-80°C. If the glass transition temperature of the thermoplastic resin is within this range, it is preferable in terms of reducing shear energy consumption during melt-kneading with the matrix resin.
In another embodiment of the present invention, the thermoplastic resin of the outermost layer has a weight average molecular weight (Mw) of 40,000 to 80,000, preferably 50,000 to 70,000. If the weight average molecular weight of the thermoplastic resin is within this range, it is preferable in terms of impact resistance and dispersibility.

The thermoplastic polymer (P) constituting the outermost layer is preferably a methacrylic acid alkyl ester having an alkyl group having 1 to 8 carbon atoms (hereinafter sometimes referred to as "methacrylic acid C _1-8 alkyl ester"). It is a polymer containing units and optionally monofunctional monomer units other than the methacrylic acid alkyl ester. The thermoplastic polymer (P) preferably does not contain polyfunctional monomer units.

The amount of methacrylic acid alkyl ester units having an alkyl group having 1 to 8 carbon atoms constituting the thermoplastic polymer (P) is preferably 75 to 100% by mass with respect to the mass of the thermoplastic polymer (P), More preferably, it is 80 to 95% by mass.

As the methacrylic acid alkyl ester having an alkyl group having 1 to 8 carbon atoms (hereinafter sometimes referred to as methacrylic acid C _1-8 alkyl ester), for example, methyl methacrylate (MMA) is preferable.

The amount of monofunctional monomer units other than methacrylic acid C _1-8 alkyl ester constituting the thermoplastic polymer (P) is preferably 0 to 25% by mass with respect to the mass of the thermoplastic polymer (P). , more preferably 5 to 20% by mass.
Monofunctional monomers other than C _1-8 alkyl methacrylate are preferably acrylic esters such as methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate and propyl acrylate, and styrene. Aromatic vinyl compounds may be mentioned.

The outermost layer may be a single layer composed of one type of thermoplastic polymer (P), or may be a multiple layer composed of two or more types of thermoplastic polymers (P).

In one preferred embodiment of the present invention, the inner layer has an intermediate layer made of the crosslinked rubber polymer (Q) and a core made of the crosslinked polymer (R) and covered in contact with the intermediate layer (inner layer = R + Q).

The crosslinked polymer (R) consists of methyl methacrylate units, monofunctional monomer units other than methyl methacrylate, and polyfunctional monomer units.

The amount of methyl methacrylate units constituting the crosslinked polymer (R) is preferably 40 to 98.5% by mass, more preferably 80 to 95% by mass, based on the mass of the crosslinked polymer (R).

The amount of monofunctional monomer units other than methyl methacrylate constituting the crosslinked polymer (R) is 1 to 59.5% by mass, preferably 5 to 20% by mass, based on the mass of the crosslinked polymer (R). %.
Monofunctional monomers other than methyl methacrylate are preferably acrylic acid esters such as methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate and propyl acrylate, and aromatic vinyl compounds such as styrene. can be mentioned.

The amount of the polyfunctional monomer unit constituting the crosslinked polymer (R) is preferably 0.05 to 0.4% by mass, more preferably 0.1 to 0.1%, based on the mass of the crosslinked polymer (R). It is 0.3% by mass.

The amount of the crosslinked polymer (R) is preferably 5 to 40% by mass, more preferably 7 to 35% by mass, still more preferably 10 to 30% by mass, based on the amount of the multi-layered rubber particles.

The crosslinked rubber polymer (Q) comprises an acrylic ester unit having an alkyl group of 1 to 8 carbon atoms, a monofunctional monomer unit other than the acrylic ester, and a polyfunctional monomer unit.

The acrylic acid ester unit having an alkyl group having 1 to 8 carbon atoms in the crosslinked rubber polymer (Q) is preferably 10 to 90% by mass, more preferably 20 to 90% by mass, based on the mass of the crosslinked rubber polymer (Q). 85% by mass.
Monofunctional monomer units other than acrylic acid ester in the crosslinked rubber polymer (Q) are preferably 10 to 90% by mass, more preferably 15 to 80% by mass, based on the mass of the crosslinked rubber polymer (Q). is.

The polyfunctional monomer unit in the crosslinked rubber polymer (Q) is preferably 0.01 to 3% by mass, more preferably 0.1 to 2% by mass, based on the mass of the crosslinked rubber polymer (Q). be.

Examples of acrylic acid esters used in the thermoplastic polymer (P), the crosslinked rubber polymer (Q), and the crosslinked polymer (R) include methyl acrylate (MA), ethyl acrylate, n-propyl acrylate, n- Mention may be made of acrylic acid alkyl esters such as butyl acrylate (BA), s-butyl acrylate, t-butyl acrylate, n-butylmethyl acrylate, n-heptyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate. These acrylic acid esters can be used singly or in combination of two or more. Among these, methyl acrylate and/or n-butyl acrylate are preferred.

Examples of polyfunctional monomer units used in the crosslinked rubber polymer (Q) and crosslinked polymer (R) include ethylene glycol dimethacrylate, propylene glycol dimethacrylate, triethylene glycol dimethacrylate, hexanediol dimethacrylate, and ethylene glycol. Diacrylates, propylene glycol diacrylate, triethylene glycol diacrylate, allyl methacrylate (ALMA), triallyl isocyanurate and the like can be mentioned.
A monofunctional monomer unit other than methyl methacrylate in the crosslinked polymer (R) and a monofunctional monomer unit other than an acrylic acid ester in the crosslinked rubber polymer (Q) are covalent with a methacrylic acid ester or an acrylic acid ester. Any polymerizable vinyl-based monomer may be used, for example, aromatic vinyl monomers such as styrene, p-methylstyrene, o-methylstyrene, vinylnaphthalene, and unsaturated nitrile-based monomers such as acrylonitrile. , ethylene, propylene and other olefinic monomers, vinyl chloride, vinylidene chloride, vinylidene fluoride and other vinyl halide monomers, acrylic acid, methacrylic acid, maleic anhydride and other unsaturated carboxylic acid monomers , vinyl acetate, N-propylmaleimide, N-cyclohexylmaleimide, No-chlorophenylmaleimide and other maleimide monomers, and these compounds can be used alone or in combination of two or more. .

<Polymerization process>
An outermost layer composed of a thermoplastic polymer (P), an inner shell composed of a crosslinked rubber polymer (Q) in contact with and covered with the outermost layer, and optionally further composed of a crosslinked polymer (R). The latex of acrylic crosslinked rubber particles containing the core can be produced according to a conventional method by polymerizing in multiple stages using a monomer mixture, a polymerization initiator, an emulsifier, and the like.
A polymerization initiator used in each polymerization is not particularly limited. Polymerization initiators include, for example, water-soluble inorganic initiators such as potassium persulfate and ammonium persulfate; redox initiators obtained by combining inorganic initiators with sulfites or thiosulfates; and organic peroxides. A redox initiator that uses a ferrous salt or sodium sulfoxylate in combination may be used. The polymerization initiator may be added to the reaction system all at once at the start of the polymerization, or may be added to the reaction system at the start of the polymerization and during the polymerization in consideration of the reaction rate. The amount of the polymerization initiator to be used can be appropriately set, for example, so that the average particle size of the granules contained in the acrylic crosslinked rubber particles is within the range described above.

The emulsifier used in each polymerization is not particularly limited. Examples of emulsifiers include anionic emulsifiers such as long-chain alkylsulfonates, alkyl sulfosuccinates, and alkylbenzenesulfonates; nonionic emulsifiers such as polyoxyethylene alkyl ethers and polyoxyethylene nonylphenyl ethers; polyoxyethylene polyoxyethylene nonylphenyl ether sulfates such as sodium nonylphenyl ether sulfate; polyoxyethylene alkyl ether sulfates such as sodium polyoxyethylene alkyl ether sulfate; alkyl ether carboxylates such as sodium polyoxyethylene tridecyl ether acetate; Examples include nonionic and anionic emulsifiers. The amount of the emulsifier to be used can be appropriately set, for example, so that the average particle size of the granules contained in the acrylic crosslinked rubber particles is within the range described above.

A preferred method for producing the coagulated powder of the present invention includes a polymerization step of producing a latex containing acrylic crosslinked rubber particles by an emulsion polymerization method, an aggregation step of aggregating the latex at 35 to 65° C. to obtain a slurry, and a A granulation step of granulating at 100 to 130°C.

The coagulated powder can be produced from the latex containing the crosslinked acrylic rubber particles of the present invention by a freezing coagulation method, a salting out coagulation method, an acid precipitation coagulation method, or the like. Among these, the salting-out coagulation method is preferable because it is possible to adjust the cohesive force of the coagulated powder and to continuously produce a high-quality coagulate.

<Aggregation process>
The agglomeration step is a slow agglomeration reaction, in which the emulsified latex and the coagulant solution are mixed in a heated state, and in order to improve the dispersibility of the acrylic crosslinked rubber particles during subsequent melt-kneading, agglomeration takes place at a slow rate. It is what makes progress.

The coagulant that can be used in the present invention may be an aqueous solution of an inorganic acid or a salt thereof, or an organic acid or a salt thereof that has the property of coagulating and coagulating the emulsion polymerized latex.

Specific inorganic acid solutions, inorganic acid salt solutions, organic acid solutions or organic acid salt solutions include, for example, sodium chloride, potassium chloride, lithium chloride, sodium bromide, potassium bromide, lithium bromide, iodine Alkali metal halides such as potassium chloride and sodium iodide; Alkali metal sulfates such as potassium sulfate and sodium sulfate; Ammonium sulfate; Ammonium chloride; Alkali metal nitrates such as sodium nitrate and potassium nitrate; Aqueous solutions of inorganic salts such as calcium acetate, zinc sulfate, copper sulfate, barium chloride, ferrous chloride, ferric chloride, magnesium chloride, ferric sulfate, aluminum sulfate, potassium alum, and iron alum, either alone or in combination of two or more. can be mentioned. Among these, aqueous solutions of salts of monovalent or divalent inorganic acids such as sodium chloride, potassium chloride, sodium sulfate, ammonium chloride, calcium chloride, magnesium chloride, magnesium sulfate, barium chloride and calcium acetate can be preferably used. The method of adding the coagulant is not particularly limited, and batch addition, divided addition, or continuous addition can be used.

The polymer concentration of the emulsified latex in the aggregation step is preferably 5-25% by mass, more preferably 7.5-22.5% by mass, still more preferably 10-20% by mass. The lower the polymer concentration of the emulsified latex, the more difficult it is for aggregation to proceed.

The concentration of the coagulant added in the aggregation step is preferably 0.1 to 10 parts by mass, more preferably 0.5 to 7.5 parts by mass, still more preferably 1.5 parts by mass, with respect to 100 parts by mass of the polymer in the emulsified latex. 0 to 7.0 parts by mass. If the concentration of the coagulant added is low, aggregation will not proceed easily, and if the concentration is high, aggregation will proceed more easily, but the hot water resistance or boiling water whitening resistance of the resulting coagulant tends to deteriorate.

The residence time in the aggregation step is preferably 0.25 to 2.0 hours, more preferably 0.5 to 1.75 hours, still more preferably 0.75 to 1.6 hours. The shorter the residence time, the smaller the particle size of the obtained coagulum due to insufficient aggregation.

<Granulation process>
In the granulation step, the slurry obtained in the first coagulation (aggregation step) is further heated to reduce fine particles that are not completely aggregated and increase the bulk density of the coagulate.

The residence time in the granulation step is preferably 0.5 to 3 hours, more preferably 0.75 to 2.75 hours, still more preferably 1.0 to 2.5 hours. The shorter the residence time, the smaller the particle size of the obtained coagulum due to insufficient granulation.

Washing and dehydration of the slurry can be performed using, for example, a filter press, a belt press, a Guina centrifuge, a screw decanter centrifuge, or the like. From the viewpoint of productivity and washing efficiency, it is preferable to use a screw decanter centrifuge. Washing and dewatering of the slurry are preferably performed at least twice. The greater the number of times of washing and dehydration, the lower the residual amount of water-soluble components. However, from the viewpoint of productivity, the number of times of washing and dehydration is preferably 3 or less.

The moisture content of the coagulum after dehydration is preferably 5 to 50% by mass, more preferably 5 to 45% by mass, still more preferably 5 to 40% by mass. The higher the moisture content, the more difficult it is to dry sufficiently, making it difficult to obtain a coagulum with a suitable moisture content after drying.
The turbidity of waste water discharged during dehydration is preferably 1000 or less, more preferably 700 or less, and even more preferably 400 or less. If the turbidity of the waste water is high, it indicates that the solid-liquid separation property is insufficient, which not only lowers the product yield, but also causes problems such as clogging of the strainer of the discharge pump, making stable operation difficult.

Drying of the coagulum is carried out so that the moisture content is preferably less than 0.2% by weight, more preferably less than 0.1% by weight. The higher the water content, the more the crosslinked acrylic rubber particles undergo an ester hydrolysis reaction during melt extrusion molding, which tends to generate a carboxyl group in the molecular chain.

The coagulated powder of the present invention comprises 60 parts by mass of methyl methacrylate resin having a melt flow rate of 8±1 g/10 min according to JIS K7210 at 230° C. and 37.3 N, and 40 parts by mass of the coagulated powder. It is defined by a series of melt-kneaded compositions that are melt-kneaded at a temperature of 230° C. and 40 rpm with a kneading/extrusion molding evaluation test device equipped with a shear energy consumption measuring device and sampled every minute. The methyl methacrylate resin has a weight average molecular weight in the range of 70,000 to 120,000 and a mass ratio of methyl methacrylate units to methyl acrylate units of 90:10 to 100:0. The series of melt-kneaded compositions were stirred in acetone at a rate of 0.1% by mass for 2 hours at room temperature to dissolve the soluble matter and disperse the insoluble matter. / Measure the particle size distribution with a scattering type particle size distribution analyzer. A sample with a short melt-kneading time has a multimodal or broad particle size distribution, and a sample with an advanced melt-kneading has a unimodal distribution.
In the coagulated powder of the present invention, the consumed shear energy E required for the first unimodal distribution of the acrylic crosslinked rubber particles to have a dispersed particle diameter of 1 μm or less in a series of melt-kneaded compositions sampled every minute is 180 MJ/m ³ or less, preferably 150 MJ/m ³ or less.
The coagulated powder of the present invention, in which the consumed shear energy E is equal to or less than the upper limit, is excellent in the dispersibility of the acrylic crosslinked rubber particles when melt-kneaded into the methacrylic resin, and the composition with the methacrylic resin is an aggregate. Reduced defects and excellent impact resistance.

<Resin composition>
Examples of the matrix resin contained in the resin composition of the present invention include methacrylic resins, polyethylene, polypropylene, polybutene-1, poly- Olefin resins such as 4-methylpentene-1 and polynorbornene, ethylene ionomers, polystyrene, styrene-maleic anhydride copolymers, high impact polystyrene, AS resins, ABS resins, AES resins, AAS resins, ACS resins, and styrene resins such as MBS resins, methyl methacrylate-styrene copolymers, ester resins such as polyethylene terephthalate and polybutylene terephthalate, amide resins such as nylon 6, nylon 66, and polyamide elastomers, polyphenylene sulfide, polyether Etherketone, polysulfone, polyphenylene oxide, polyimide, polyetherimide, polycarbonate, polyvinyl chloride, polyvinylidene chloride, polyvinylidene fluoride, polyvinyl alcohol, ethylene-vinyl alcohol copolymer, polyacetal, phenoxy resin, etc., and methacrylic based resins are preferred. Matrix resins can be used alone or in combination of two or more.

The resin composition of the present invention may contain various additives as necessary. Additives include antioxidants, heat deterioration inhibitors, UV absorbers, light stabilizers, lubricants, release agents, polymer processing aids, antistatic agents, flame retardants, dyes/pigments, light diffusing agents, gloss erasing agents, anti-sticking agents, impact modifiers, phosphors, and the like. The content of these additives can be appropriately set within a range that does not impair the effects of the present invention. The content of the agent is 0.01 to 3 parts by mass, the content of the light stabilizer is 0.01 to 3 parts by mass, the content of the lubricant is 0.01 to 3 parts by mass, and the content of the dye/pigment is 0.01 to 3 parts by mass. 01 to 3 parts by mass, and the anti-adhesion agent is preferably 0.001 to 1 part by mass. Other additives can also be added in the range of 0.01 to 3 parts by weight.

Antioxidants are effective by themselves to prevent oxidation deterioration of resins in the presence of oxygen. Examples include phosphorus antioxidants, phenolic antioxidants, sulfur antioxidants, and amine antioxidants. Among them, from the viewpoint of preventing deterioration of optical properties due to coloring, phosphorus antioxidants and phenolic antioxidants are preferable, and phenolic antioxidants are used alone or in combination with phosphorus antioxidants and phenolic antioxidants. Combined use is more preferred. When a phosphorus antioxidant and a phenolic antioxidant are used in combination, it is preferable to use the phosphorus antioxidant/phenolic antioxidant at a mass ratio of 0.2/1 to 2/1, and 0.2/1 to 2/1. It is more preferable to use 5/1 to 1/1.

Phosphorus-based antioxidants include 2,2-methylenebis(4,6-di-t-butylphenyl)octyl phosphite (manufactured by ADEKA Co., Ltd. "ADEKA STAB HP-10"), tris (2,4-di-t -butylphenyl) phosphite ("IRGAFOS168" manufactured by BASF Japan Ltd.), and 3,9-bis(2,6-di-t-butyl-4-methylphenoxy)-2,4,8,10-tetraoxa- 3,9-diphosphaspiro[5.5]undecane (“ADEKA STAB PEP-36” manufactured by ADEKA Co., Ltd.) and the like are preferable.

Phenolic antioxidants include pentaerythrityl-tetrakis [3-(3,5-di-t-butyl-4-hydroxyphenyl) propionate] (manufactured by BASF Japan Ltd. "IRGANOX1010"), and octadecyl-3- (3,5-Di-t-butyl-4-hydroxyphenyl) propionate (“IRGANOX1076” manufactured by BASF Japan Ltd.) and the like are preferred.
Preferred sulfur-based antioxidants include dilauryl 3,3'-thiodipropionate, distearyl 3,3'-thiodipropionate, pentaerythritol tetrakis(3-laurylthiopropionate), and the like.
As the amine-based antioxidant, octylated diphenylamine and the like are preferable.

The thermal degradation inhibitor can prevent thermal degradation of the resin by capturing polymer radicals generated when exposed to high temperatures under substantially oxygen-free conditions. As the heat deterioration inhibitor, 2-t-butyl-6-(3'-t-butyl-5'-methyl-hydroxybenzyl)-4-methylphenyl acrylate ("Sumilizer GM" manufactured by Sumitomo Chemical Co., Ltd.), and 2,4-di-t-amyl-6-(3′,5′-di-t-amyl-2′-hydroxy-α-methylbenzyl)phenyl acrylate (“Sumilizer GS” manufactured by Sumitomo Chemical Co., Ltd.), etc. preferable.

A UV absorber is a compound that is said to have an ability to absorb UV rays and mainly has the function of converting light energy into heat energy. Examples of UV absorbers include benzophenones, benzotriazoles, triazines, benzoates, salicylates, cyanoacrylates, oxalic acid anilides, malonic acid esters, and formamidines. Among them, benzotriazoles and triazines are preferred. 1 type(s) or 2 or more types can be used for an ultraviolet absorber.

A photostabilizer is a compound that is said to have a function of scavenging radicals generated mainly by oxidation by light. Suitable light stabilizers include hindered amines such as compounds having a 2,2,6,6-tetraalkylpiperidine backbone. Examples thereof include bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate ("ADEKA STAB LA-77Y" manufactured by ADEKA Co., Ltd.).

A lubricant is a compound that is said to have the effect of adjusting the slippage between a resin and a metal surface and preventing adhesion or sticking to improve releasability, processability, and the like. Examples include higher alcohols, hydrocarbons, fatty acids, fatty acid metal salts, fatty amides, and fatty acid esters. Among them, from the viewpoint of compatibility with the resin composition of the present invention, aliphatic monohydric alcohols and aliphatic amides having 12 to 18 carbon atoms are preferred, and aliphatic amides are more preferred. Aliphatic amides are classified into saturated aliphatic amides and unsaturated aliphatic amides, and unsaturated aliphatic amides are more preferable because they are expected to have a slip effect due to adhesion prevention. Examples of unsaturated aliphatic amides include N,N'-ethylenebisoleic acid amide ("Slipax O" manufactured by Nippon Kasei Co., Ltd.) and N,N'-dioleyladipate amide ("Slipax ZOA" manufactured by Nippon Kasei Co., Ltd.). ”) and the like.

Release agents include higher alcohols such as cetyl alcohol and stearyl alcohol; glycerin higher fatty acid esters such as stearic acid monoglyceride and stearic acid diglyceride; In the present invention, it is preferable to use higher alcohols and glycerin fatty acid monoester in combination as the release agent. When higher alcohols and glycerin fatty acid monoesters are used in combination, the ratio is not particularly limited, but the amount of higher alcohols used: the amount of glycerin fatty acid monoesters used is in a mass ratio of 2.5:1 to 3.5. 5:1 is preferred, and 2.8:1 to 3.2:1 is more preferred.
A polymer processing aid is a compound that exerts an effect on thickness accuracy and thinning when molding a resin composition. Polymeric processing aids are typically polymer particles having a particle size of 0.05 to 0.5 μm, which can be produced by emulsion polymerization methods.

Antistatic agents include sodium heptylsulfonate, sodium octylsulfonate, sodium nonylsulfonate, sodium decylsulfonate, sodium dodecylsulfonate, sodium cetylsulfonate, sodium octadecylsulfonate, sodium diheptylsulfonate, heptylsulfonic acid Potassium, potassium octylsulfonate, potassium nonylsulfonate, potassium decylsulfonate, potassium dodecylsulfonate, potassium cetylsulfonate, potassium octadecylsulfonate, potassium diheptylsulfonate, lithium heptylsulfonate, lithium octylsulfonate, nonylsulfonate Alkyl sulfonates such as lithium oxide, lithium decylsulfonate, lithium dodecylsulfonate, lithium cetylsulfonate, lithium octadecylsulfonate, and lithium diheptylsulfonate.

Examples of flame retardants include magnesium hydroxide, aluminum hydroxide, hydrated aluminum silicate, hydrated magnesium silicate, metal hydrates having hydroxyl groups or water of crystallization such as hydrotalcite, and phosphoric acids such as amine polyphosphate and phosphate esters. trimethyl phosphate, triethyl phosphate, tripropyl phosphate, tributyl phosphate, tripentyl phosphate, trihexyl phosphate, tricyclohexyl phosphate, triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, dimethylethyl Phosphate flame retardants such as phosphate, methyldibutyl phosphate, ethyldipropyl phosphate and hydroxyphenyldiphenyl phosphate are preferred.

Dyes and pigments include red organic pigments such as para red, fire red, pyrazolone red, thioindicole red, and perylene red; blue organic pigments such as cyanine blue and indanthrene blue; and green organic pigments such as cyanine green and naphthol green. Pigments may be mentioned, and one or more of these may be used.
Light diffusing agents and matting agents include fine glass particles, polysiloxane-based crosslinked fine particles, crosslinked polymer fine particles, talc, calcium carbonate, barium sulfate, and the like. The copolymer of the present invention preferably does not contain an acid generator.

Anti-adhesion agents include fatty acids such as stearic acid and palmitic acid; fatty acid metal salts such as calcium stearate, zinc stearate, magnesium stearate, potassium palmitate and sodium palmitate; polyethylene wax, polypropylene wax, montanic acid wax and the like. waxes; Low molecular weight polyolefins such as low molecular weight polyethylene and low molecular weight polypropylene; Acrylic resin powder; Polyorganosiloxane such as dimethylpolysiloxane; powder, fluororesin powder such as tetrafluoroethylene resin, molybdenum disulfide powder, silicone resin powder, silicone rubber powder, silica and the like.
Examples of impact modifiers include core-shell modifiers containing diene rubber as a core layer component; modifiers containing a plurality of rubber particles, and the like.
Examples of phosphors include fluorescent pigments, fluorescent dyes, fluorescent white dyes, fluorescent whitening agents, and fluorescent bleaching agents.

When the resin composition of the present invention contains a matrix resin and/or an additive, it may be added during polymerization of the matrix resin and/or the acrylic crosslinked rubber particles. may be added at the time of mixing, or may be added after mixing the matrix resin and/or acrylic crosslinked rubber particles.

The resin composition of the present invention can be molded using a molding method and molding apparatus generally used for matrix resins. For example, a molded product can be produced by a molding method involving heating and melting such as injection molding, extrusion molding, compression molding, blow molding, calendar molding, vacuum molding, or a solution casting method.

The resin composition of the present invention is also useful as a film, and can be processed well by, for example, usual melt extrusion methods such as inflation method, T-die extrusion method, calendering method, and solution casting method. In addition, if necessary, by simultaneously contacting both sides of the film with a roll or a metal belt, in particular, by simultaneously contacting a roll or a metal belt heated to a temperature higher than the glass transition temperature, the film has a better surface property. It is also possible to obtain In addition, depending on the purpose, it is also possible to modify the film by laminate molding or biaxial stretching.

A film obtained from the resin composition of the present invention can be used by being laminated on metal, plastic, or the like. Examples of lamination methods include wet lamination in which an adhesive is applied to a metal plate such as a steel plate and then a film is placed on the metal plate, dried, and laminated, dry lamination, extrusion lamination, hot melt lamination, and the like.

As a method of laminating a film on a plastic part, the film is placed in a mold and filled with resin by injection molding, such as film insert molding, laminate injection press molding, or preforming the film and then placing it in the mold. Examples include film in-mold molding in which a film is arranged and resin is filled by injection molding.

The resin composition of the present invention and molded articles containing it can be used as members for various uses. Specific applications include, for example, signboard parts and marking films; display parts; lighting parts; interior parts; Transportation equipment parts such as automotive exterior parts such as bumpers; Electronic equipment parts; Medical equipment parts; Mechanical parts; optical-related parts such as; traffic-related parts; and other various surface materials.
On the other hand, laminate laminates of films obtained from the resin composition of the present invention include interior and exterior materials for automobiles, daily necessities, wallpaper, paint substitute applications, housings for furniture and electrical equipment, housings for OA equipment such as facsimiles, It can be used for flooring, parts of electrical or electronic devices, bathroom fixtures and the like.

Production examples and examples according to the present invention and comparative examples will be described below.

[Evaluation items and evaluation methods]
Evaluation items and evaluation methods in Production Examples, Examples and Comparative Examples are as follows.
(Weight average molecular weight (Mw))
The weight average molecular weight (Mw) of the resin was determined by the GPC method. Tetrahydrofuran was used as the eluent. As a column, two TSKgel SuperMultipore HZM-M manufactured by Tosoh Corporation and SuperHZ4000 connected in series were used. As a GPC apparatus, HLC-8320 (product number) manufactured by Tosoh Corporation equipped with a differential refractive index detector (RI detector) was used. A sample solution was prepared by dissolving 4 mg of the resin to be measured in 5 mL of tetrahydrofuran. The temperature of the column oven was set to 40° C., the eluent flow rate was 0.35 mL/min, 20 μL of the sample solution was injected into the device, and the chromatogram was measured. Ten points of standard polystyrene having a molecular weight in the range of 400 to 5,000,000 were subjected to GPC measurement to prepare a calibration curve showing the relationship between retention time and molecular weight. Based on this calibration curve, the Mw of the resin to be measured was determined.

(Volume average particle size)
The volume-average particle size of the latex containing the acrylic crosslinked rubber particles was determined by a light scattering method using a laser diffraction/scattering particle size distribution analyzer LA-950V2 manufactured by Horiba, Ltd.

(Shear energy consumed)
60 parts by mass of methyl methacrylate resin (Parapet G manufactured by Kuraray Co., Ltd.) having a melt flow rate of 8 g/10 minutes at 230 ° C. and 37.3 N is kneaded and extruded with a shear energy consumption measuring device (Toyo Seiki Lab. After kneading for 3 minutes at 230° C. and 80 rpm using a sigma mixer in Plastomill 4C150), 40 parts by mass of coagulated powder was added and further kneaded at 40 rpm. A melt-kneaded composition with different shear energy consumption was obtained by sampling every minute during kneading. 0.10 parts by mass of each of the resulting melt-kneaded compositions was dissolved in 100 parts by mass of acetone for 2 hours, and the dispersion was subjected to light scattering using a laser diffraction/scattering particle size distribution analyzer LA-950V2 manufactured by Horiba, Ltd. The volume average dispersed particle size of the acrylic crosslinked rubber particles dispersed in the methacrylic resin was measured by the method. When the range of 1 μm or less and one distribution peak (unimodal) appeared, it was considered to be dispersed in primary particles, and the shear energy consumption of the resin composition was adopted as the shear energy consumption of the solidified powder. .

(Charpy impact value)
The impact value (notched) of the press-molded sample was measured by a method according to JIS-K7111 under the conditions of a temperature of 23° C. and a relative humidity of 50%. Measurement was performed five times, and the average value was adopted as the Charpy impact value.

(number of defects)
For the pellets of the acrylic resin composition obtained in Examples or Comparative Examples, using an extruder ME-20/26V2 and a winder CR-8 attached to the polymer quality inspection device manufactured by OCS, the cylinder temperature is 240 to 250 ° C. , and a T-die temperature of 260° C. with a width of 150 mm. Defects of 40 μm or more were measured on the obtained film using the polymer quality inspection apparatus FSA-100, and the number of defects per 1 m ² was adopted as the number of different defects (number of defects).

(Production example 1)
In a reactor equipped with a stirrer, a thermometer, a nitrogen gas inlet tube, a monomer inlet tube and a reflux condenser, 750 parts by mass of ion-exchanged water, 0.14 parts by mass of sodium polyoxyethylene tridecyl ether acetate and sodium carbonate were added. 0.1 part by mass was charged, and the inside of the reactor was sufficiently replaced with nitrogen gas. The internal temperature was then raised to 80°C. 0.10 parts by mass of potassium persulfate was added thereto and stirred for 5 minutes. To this, 262.5 parts by mass of a monomer mixture consisting of 93.8% by mass of methyl methacrylate (MMA), 6.0% by mass of methyl acrylate (MA) and 0.2% by mass of allyl methacrylate (ALMA) was added. It was added dropwise continuously over 45 minutes. After completion of dropping, the polymerization reaction was further carried out for 60 minutes so that the polymerization conversion rate was 98% or more (first layer (R)).
Next, 0.10 parts by mass of potassium persulfate was put into the same reactor and stirred for 5 minutes. After that, 337.5 parts by mass of a monomer mixture consisting of 80.6% by mass of butyl acrylate (BA), 17.4% by mass of styrene (St) and 2% by mass of allyl methacrylate (ALMA) was added continuously over 60 minutes. dropwise. After the completion of dropping, the polymerization reaction was further carried out for 80 minutes so that the polymerization conversion rate was 98% or more (first layer (R) + second layer (Q)). Next, 0.10 parts by mass of potassium persulfate was put into the same reactor and stirred for 5 minutes. After that, 150 parts by mass of a monomer mixture consisting of 80.0% by mass of methyl methacrylate (MMA) and 20.0% by mass of methyl acrylate (MA) and 0.3 parts by mass of n-octyl mercaptan were added continuously over 25 minutes. dropwise. After completion of the dropwise addition, the polymerization reaction was further carried out for 60 minutes so that the polymerization conversion rate was 98% or higher. Through the above operations, a latex containing acrylic crosslinked rubber particles was obtained (first layer (R) + second layer (Q) + third layer (P)). The volume average particle size of the acrylic crosslinked rubber particles in the latex was 0.26 μm.

(Production example 2)
A latex containing a crosslinked rubber polymer was obtained in the same manner as in Production Example 1 up to the first and second layers.
Next, 0.10 parts by mass of potassium persulfate was put into the same reactor and stirred for 5 minutes. After that, 150 parts by weight of a monomer mixture consisting of 94.0% by weight of methyl methacrylate and 6.0% by weight of methyl acrylate and 0.3 parts by weight of n-octyl mercaptan were continuously added dropwise over 25 minutes. After completion of the dropwise addition, the polymerization reaction was further carried out for 60 minutes so that the polymerization conversion rate was 98% or higher. Through the above operations, a latex containing acrylic crosslinked rubber particles (three-layer structure: RQP) was obtained. The volume average particle size of the acrylic crosslinked rubber particles in the latex was 0.23 μm.

(Production example 3)
A latex containing a crosslinked rubber polymer was obtained in the same manner as in Production Example 1 up to the first and second layers.
Next, 0.10 parts by mass of potassium persulfate was put into the same reactor and stirred for 5 minutes. Thereafter, 150 parts by mass of a monomer mixture consisting of 94.0% by mass of methyl methacrylate and 6.0% by mass of methyl acrylate and 1.125 parts by mass of n-octylmercaptan were continuously added dropwise over 25 minutes. After completion of the dropwise addition, the polymerization reaction was further carried out for 60 minutes so that the polymerization conversion rate was 98% or higher. Through the above operations, a latex containing acrylic crosslinked rubber particles (three-layer structure: RQP) was obtained. The volume average particle size of the acrylic crosslinked rubber particles in the latex was 0.29 μm.

(Production example 4)
A latex containing a crosslinked rubber polymer was obtained in the same manner as in Production Example 1 up to the first and second layers.
Next, 0.10 parts by mass of potassium persulfate was put into the same reactor and stirred for 5 minutes. Thereafter, 150 parts by weight of a monomer mixture consisting of 86.0% by weight of methyl methacrylate and 14.0% by weight of butyl acrylate and 0.3% by weight of n-octyl mercaptan were continuously added dropwise over 25 minutes. After completion of the dropwise addition, the polymerization reaction was further carried out for 60 minutes so that the polymerization conversion rate was 98% or higher. Through the above operations, a latex containing acrylic crosslinked rubber particles (three-layer structure: RQP) was obtained. The volume average particle size of the acrylic crosslinked rubber particles in the latex was 0.29 μm.

(Production example 5)
A latex containing a crosslinked rubber polymer was obtained in the same manner as in Production Example 1 up to the first and second layers.
Next, 0.10 parts by mass of potassium persulfate was put into the same reactor and stirred for 5 minutes. Thereafter, 150 parts by mass of a monomer mixture consisting of 86.0% by mass of methyl methacrylate and 14.0% by mass of butyl acrylate and 1.125 parts by mass of n-octylmercaptan were continuously added dropwise over 25 minutes. After completion of the dropwise addition, the polymerization reaction was further carried out for 60 minutes so that the polymerization conversion rate was 98% or higher. Through the above operations, a latex containing acrylic crosslinked rubber particles (three-layer structure: RQP) was obtained. The volume average particle size of the acrylic crosslinked rubber particles in the latex was 0.29 μm.

[Example 1]
The latex obtained in Production Example 1 was coagulated under the following conditions. 484.8 parts of deionized water and 5.25 parts of magnesium sulfate were added to 210 parts of latex, and the liquid temperature was raised to 40° C. while stirring. Stirring was continued for 1.1 hours while maintaining the liquid temperature at 40° C. to obtain an aggregated slurry. Further, the temperature of this slurry was raised to 115° C., and stirring was continued for 1.6 hours while maintaining the temperature to obtain a granulated slurry. The resulting granulated slurry was washed and dewatered using a screw decanter centrifuge, and dried to obtain a coagulated powder. The volume average particle size of the coagulated powder was 239 μm.
40 parts by mass of the solidified powder obtained and 60 parts by mass of methacrylic resin were melt-kneaded at a cylinder temperature of 170 to 235° C. with a single-screw extruder of Φ40 mm. Thereafter, the molten resin composition was extruded to obtain a pellet-shaped acrylic resin composition, and the number of defects was measured by the method described above.
Further, 40 parts by mass of the solidified powder obtained and 60 parts by mass of methacrylic resin were kneaded at 230° C. for 3 minutes in a Laboplastomill (4C150 manufactured by Toyo Seiki Co., Ltd.) to obtain an acrylic resin composition. The dispersed particle size distribution in acetone indicated was measured. Further, a molded article having a thickness of 3 mm was obtained by hot press molding at 230° C. for 4 minutes and 30 seconds, and the Charpy impact value was measured. Table 2 shows the physical property evaluation results.

[Examples 2 to 4]
A coagulated powder was obtained in the same manner as in Example 1, except that the temperature shown in Table 2 and the acrylic crosslinked rubber particles were changed. In each example, in the same manner as in Example 1, the obtained coagulated powder was used to obtain a molded product. Table 2 shows the physical property evaluation results in each example.

[Comparative Examples 1 to 6]
A coagulated powder was obtained in the same manner as in Example 1, except that the temperature, the acrylic crosslinked rubber particles, and the particles for dispersion were changed as shown in Table 3. In each comparative example, the same procedure as in Example 1 was carried out to obtain a molded product using the obtained coagulated powder. Table 3 shows the physical property evaluation results in each comparative example. Further, 40 parts by mass of the coagulated powder obtained in Comparative Example 1 and 60 parts by mass of methacrylic resin were kneaded at 230° C. for 3 minutes in a Laboplastomill to obtain an acrylic resin composition, and the acetone shown in FIG. The dispersed particle size distribution was measured in

The molded articles obtained in Examples 1 to 4, which were made of the coagulated powder containing the acrylic crosslinked rubber particles of the present invention, had good dispersibility and impact resistance.

On the other hand, the molded articles obtained in Comparative Examples 1 and 2, which consist of coagulated powder containing acrylic crosslinked rubber particles with a high third layer glass transition temperature, have a large number of defects compared to the examples. The impact resistance strength was poor.

The molded article obtained in Comparative Example 3, which is composed of the coagulated powder containing acrylic crosslinked rubber particles produced by increasing the aggregation temperature in the step of obtaining the coagulated powder, has a large number of defects as compared with the examples. , the impact resistance strength was poor.

The molded article obtained in Comparative Example 4, which is composed of a coagulated powder containing acrylic crosslinked rubber particles having a low molecular weight in the outermost layer, had poor impact strength as compared with Examples.

The molded article obtained in Comparative Example 5, which is made of the coagulated powder containing acrylic crosslinked rubber particles produced by lowering the molecular weight of the outermost layer and increasing the granulation temperature in the step of obtaining the coagulated powder, Compared to , the number of defects was large, and the impact resistance strength was poor.

The molded article obtained in Comparative Example 6, which is composed of the coagulated powder containing the acrylic crosslinked rubber particles obtained by adding the dispersing particles, has a lower rubber content as a whole, and is more durable than the examples. The impact strength was poor.

Claims (6)

It has an inner layer containing crosslinked rubber containing alkyl acrylate units and an outermost layer made of a thermoplastic resin containing methyl methacrylate units and graft-bonded to the inner layer, wherein the thermoplastic resin of the outermost layer has a glass transition A coagulated powder containing acrylic crosslinked rubber particles having a temperature of 60 to 85° C., a weight average molecular weight of 40,000 to 80,000, and an average particle size of 0.08 to 0.3 μm,
60 parts by mass of methyl methacrylate resin having a melt flow rate of 8±1 g/10 minutes at 230° C. and 37.3 N and 40 parts by mass of the solidified powder were kneaded and extruded using a kneading/extrusion evaluation test apparatus equipped with a shear energy consumption measuring device. , when melt-kneading at a temperature of 230 ° C.,
Until the acrylic crosslinked rubber particles are unimodally dispersed with a dispersed particle diameter of 1 μm or less in a 0.1% by mass acetone dispersion of the melt-kneaded composition of the coagulated powder and the methyl methacrylate resin. A solidified powder having a required shear energy consumption E of 180 MJ/m ³ or less. The coagulated powder according to claim 1, wherein the acrylic crosslinked rubber particles have an average particle size of 0.2 to 0.3 µm. a polymerization step of producing a latex containing acrylic crosslinked rubber particles by an emulsion polymerization method;
aggregating step of aggregating the latex at 35-65°C;
The method for producing a coagulated powder according to claim 1 or 2, further comprising a granulation step of granulating at 100 to 130°C. A resin composition comprising the coagulated powder according to claim 1 or 2 and a matrix resin. 5. The resin composition according to claim 4, wherein the matrix resin is a methacrylic resin. A molded article comprising the resin composition according to claim 4 or 5.

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