JP2011153291A - Multilayered polymer particle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To comprise multilayer polymer particles capable of achieving both excellent stress whitening resistance and elongation (tensile strength) when incorporated in a film, a methacrylic resin composition containing the same, and the methacrylic resin composition Provide film.
[Solution]
Multilayer polymer particles comprising the following elastic polymer layer (A) and hard polymer layer (B) in this order from the center of the particle toward the outer surface.
Elastic polymer layer (A): alkyl acrylate 50-99.9 parts by weight (hereinafter referred to as part), predetermined monofunctional monomer 0-49.9 parts, and predetermined polyfunctional monomer 0.1 A polymer layer obtained by polymerizing 10 parts and polymerizing while the weight parts of the polyfunctional monomer continuously increase from the inside.
Hard polymer layer (B): A polymer layer formed by polymerizing 50 to 100 parts of alkyl methacrylate, 0 to 50 parts of a predetermined monofunctional monomer, and 0 to 3 parts of a predetermined polyfunctional monomer.
[Selection figure] None

Description

  The present invention relates to a (meth) acrylic multilayer polymer particle useful for, for example, an impact modifier for films, a methacrylic resin composition containing the multilayer polymer particle and a methacrylic resin, and the composition. The present invention relates to films useful for automobile interior materials, home appliance exterior materials, building materials (exterior), and the like.

  (Meth) acrylic multilayer polymers are used as impact resistance improvers for films. For example, Patent Documents 1 to 5 include acrylic elastic polymer layers, alkyl methacrylates, and the like. A hard polymer layer formed by polymerizing a smaller amount of butyl acrylate or methyl acrylate, and the two layers of layers formed by forming the hard polymer layer in close contact with the outside of the acrylic elastic polymer layer A multilayer polymer containing a coalesced layer is described.

JP 2009-13318 A JP-A-3-39350 JP 2003-73520 A JP 2004-137299 A JP 2009-24112 A

  However, in a film-like methacrylic resin composition obtained by blending the above-mentioned conventional multilayer polymer with a methacrylic resin, it is difficult to have both physical properties of both stress whitening resistance and elongation.

  Accordingly, the present invention provides multilayer polymer particles capable of achieving both excellent stress whitening resistance and elongation (tensile strength) when incorporated in a film, a methacrylic resin composition containing the same, and the methacrylic resin composition It is an object to provide a film made of an object.

  As a result of intensive studies to solve the above problems, the present inventors have completed the present invention.

That is, this invention consists of the following structures.
(1) Multilayer polymer particles comprising the following elastic polymer layer (A) and hard polymer layer (B) in this order from the center of the particle toward the outer surface.
Elastic polymer layer (A): 50-99.9 parts by weight of alkyl acrylate, 0-49.9 parts by weight of monofunctional monomer having one double bond capable of radical polymerization, and double radical capable of radical polymerization A polymer layer obtained by polymerizing 0.1 to 10 parts by weight of a polyfunctional monomer having two or more bonds, and polymerizing while continuously increasing the weight part of the polyfunctional monomer from the inside.
Hard polymer layer (B): 50-100 parts by weight of alkyl methacrylate, 0-50 parts by weight of monofunctional monomer having one radical polymerizable double bond, and two radical polymerizable double bonds A polymer layer formed by polymerizing 0 to 3 parts by weight of the polyfunctional monomer.
(2) The multilayer weight according to (1), wherein the elastic polymer layer (A) is 30 to 95 parts by weight relative to 100 parts by weight of the total of the elastic polymer layer (A) and the hard polymer layer (B). Coalesced particles.
(3) A methacrylic resin composition containing 1 to 99 parts by weight of the multilayer polymer particles according to (1) or (2) and 99 to 1 part by weight of a methacrylic resin (C).
(4) The methacrylic resin composition (C) according to (3), wherein 70 to 100 parts by weight of an alkyl methacrylate and 0 to 30 parts by weight of a monomer copolymerizable therewith are polymerized. .
(5) A film comprising the methacrylic resin composition according to (3) or (4).

  According to the multilayer polymer particle of the present invention, when this multilayer polymer is incorporated into a methacrylic resin composition to form a film, a film having both excellent stress whitening resistance and elongation (tensile strength) physical properties is obtained. For example, it can be suitably used for interior materials for automobiles, exterior materials for household electrical appliances, construction materials (exterior), and the like.

It is a schematic diagram showing an example of the aspect of the power feed method which supplies each monomer component to a polymerization reactor.

The multilayer polymer particle of the present invention comprises an elastic polymer layer (A) and a hard polymer layer (B) in this order from the center of the particle toward the outer surface.
The elastic polymer layer (A) used herein is composed of 50 to 99.9 parts by weight of alkyl acrylate, 0 to 49.9 parts by weight of a monofunctional monomer having one radical-polymerizable double bond, and radical polymerization. 0.1 to 10 parts by weight of a polyfunctional monomer having two or more possible double bonds is polymerized, and the weight part of the polyfunctional monomer is continuously increased from the inside of the multilayer polymer particle. The hard polymer layer (B) is a polymer layer formed by polymerization while the alkyl methacrylate is 50 to 100 parts by weight and the monofunctional monomer having one radical-polymerizable double bond is 0 to 50 parts by weight. And 0 to 3 parts by weight of a polyfunctional monomer having two or more double bonds capable of radical polymerization.

  The elastic polymer layer (A) contains 0.1 to 10 polyfunctional monomers containing alkyl acrylate in a range of 50 to 99.9 parts by weight and having two or more double bonds capable of radical polymerization. Monomer component which is contained in the range of 0 part by weight and may contain a monofunctional monomer having one radical-polymerizable double bond in the range of 0 to 49.9 parts by weight The total amount of the body component is 100 parts by weight), and the weight of the polyfunctional monomer is polymerized while continuously increasing from the inside of the multilayer polymer particles. The content of alkyl acrylate is preferably 55 to 80 parts by weight, and the content of the polyfunctional monomer is preferably 0.2 to 8 parts by weight. The monofunctional monomer is a component that can be optionally contained, and the content thereof is preferably 20 to 45 parts by weight. When the content of the polyfunctional monomer in the monomer component constituting the elastic polymer layer (A) is less than 0.1 parts by weight, sufficient stress whitening resistance is obtained when it is contained in the film. On the other hand, if it is 10% by weight or more, sufficient elongation cannot be obtained when it is contained in the film.

  As an alkyl acrylate for obtaining an elastic polymer layer (A), what has a C1-C8 alkyl group can be normally used. Among them, those having an alkyl group having 4 to 8 carbon atoms such as butyl acrylate and 2-ethylhexyl acrylate are preferable. In addition, these alkyl acrylates may be only 1 type, and 2 or more types may be sufficient as them.

The polyfunctional monomer having two or more radical polymerizable double bonds for obtaining the elastic polymer layer (A) functions as a so-called crosslinking agent.
Examples of the polyfunctional monomer include unsaturated carboxylic acid diesters of glycols such as ethylene glycol dimethacrylate and butanediol dimethacrylate; unsaturated carboxylic acids such as allyl acrylate, allyl methacrylate, and allyl cinnamate. Alkenyl esters of acids; polyalkenyl esters of polybasic acids such as diallyl phthalate, diallyl maleate, triallyl cyanurate, triallyl isocyanurate; unsaturated carboxylic acid esters of polyhydric alcohols such as trimethylolpropane triacrylate Divinylbenzene and the like. Of these, alkenyl esters of unsaturated carboxylic acids and polyalkenyl esters of polybasic acids are particularly preferred. In addition, these polyfunctional monomers may be only 1 type, and 2 or more types may be sufficient as them.

  Examples of the monofunctional monomer having one radical-polymerizable double bond for obtaining the elastic polymer layer (A) include methacrylic acid esters such as methyl methacrylate, butyl methacrylate, and cyclohexyl methacrylate; Aromatic vinyl compounds such as styrene; vinylcyan compounds such as acrylonitrile; and the like. In addition, these monofunctional monomers may be only 1 type, and 2 or more types may be sufficient as them.

The elastic polymer layer (A) is polymerized while continuously increasing the weight part of the polyfunctional monomer.
This is because polymerization proceeds while the weight part of the polyfunctional monomer continuously increases from the inner side (center side of the multilayer polymer particle) to the outer side (outer surface side of the multilayer polymer particle) of the polymer layer. It is a site. As a specific example, the polyfunctional monomer unit is continuously increased from 0 to 5.0 parts by weight from the inner side to the outer side of the polymer layer, but is not limited thereto. It is not a thing.

  The hard polymer layer (B) contains 50 to 100 parts by weight of alkyl methacrylate and 0 to 3 parts by weight of a polyfunctional monomer having two or more double bonds capable of radical polymerization. May be contained in the range of 0 to 50 parts by weight of a monofunctional monomer having one radical polymerizable double bond (wherein the total amount of monomer components) Is 100% by weight). The content of alkyl methacrylate is preferably 60 to 98 parts by weight. Further, the polyfunctional monomer is a component that can be optionally contained, but if the content exceeds 3 parts by weight, there is a possibility that sufficient extensibility may not be obtained when it is contained in the film, The content is preferably 1 part by weight or less. The monofunctional monomer is a component that can be optionally contained, and the content thereof is preferably 2 to 40 parts by weight.

  As the alkyl methacrylate for obtaining the hard polymer layer (B), those having an alkyl group having about 1 to 8 carbon atoms are usually used. For example, methyl methacrylate, ethyl methacrylate, butyl methacrylate, Examples include 2-ethylhexyl methacrylate and cyclohexyl methacrylate. These alkyl methacrylates may be only one kind or two or more kinds.

  The polyfunctional monomer having two or more radically polymerizable double bonds for obtaining the hard polymer layer (B) functions as a so-called crosslinking agent. Specifically as this polyfunctional monomer, the thing similar to the polyfunctional monomer for obtaining the elastic polymer (A) mentioned above can be illustrated. For example, unsaturated carboxylic acid diesters of glycols such as ethylene glycol dimethacrylate, butanediol dimethacrylate; alkenyl esters of unsaturated carboxylic acids such as allyl acrylate, allyl methacrylate, allyl cinnamate; diallyl phthalate; Examples thereof include polyalkenyl esters of polybasic acids such as diallyl maleate, triallyl cyanurate and triallyl isocyanurate; unsaturated carboxylic acid esters of polyhydric alcohols such as trimethylolpropane triacrylate; divinylbenzene and the like. Of these, unsaturated carboxylic acid diesters of glycols, alkenyl esters of unsaturated carboxylic acids, and polyalkenyl esters of polybasic acids are particularly preferred. In addition, these polyfunctional monomers may be only 1 type, and 2 or more types may be sufficient as them.

  Examples of the monofunctional monomer having one radical polymerizable double bond for obtaining the hard polymer layer (B) include methyl acrylate, ethyl acrylate, butyl acrylate, and cyclohexyl acrylate. Acrylic esters; aromatic vinyl compounds such as styrene; vinylcyan compounds such as acrylonitrile. These monofunctional monomers may be used alone or in combination of two or more.

  In the multilayer polymer particle of the present invention, the weight ratio of the elastic polymer layer (A) and the hard polymer layer (B) (weight ratio of monomer components constituting each layer) is within the range where the effects of the present invention are exhibited. For example, the elastic polymer layer (A) may be 30 to 95 parts by weight with respect to a total of 100 parts by weight of the elastic polymer layer (A) and the hard polymer layer (B). The amount is preferably 40 to 80 parts by weight. When the total amount of the elastic polymer layer (A) is less than the above ratio, there is a possibility that sufficient stress whitening resistance and elongation cannot be obtained when the resulting multilayer polymer particles are contained in the film. On the other hand, when the ratio is higher than the above ratio, the uniform dispersibility of the multilayer polymer in the film may be lowered.

  Next, the manufacturing method of the multilayer polymer particle of this invention is demonstrated. The multilayer polymer particles of the present invention can be produced as a latex containing the multilayer polymer particles by an emulsion polymerization method, and further, through a subsequent purification operation, the particulate multilayer polymer is converted into a powder. Obtainable. Here, although the production method of the multilayer polymer particle which consists of two layers provided with an elastic polymer layer (A) and a hard polymer layer (B) is mentioned as an example, this invention is not limited to this. .

First, a method for producing the elastic polymer layer (A) will be described.
Under an inert gas atmosphere such as nitrogen, an alkyl acrylate, a polyfunctional monomer having two or more double bonds capable of radical polymerization in an aqueous medium containing an emulsifier, a polymerization initiator, etc., and if necessary, a radical By supplying a monofunctional monomer having one polymerizable double bond (for example, alkyl methacrylate, styrene, etc.), they are polymerized. Here, the polyfunctional monomer is supplied while its weight part is continuously increased.
Examples of such a supply method include a method referred to as a so-called power feed method, in addition to a method of supplying the polyfunctional monomer from different supply paths while changing the supply rate.
As shown in FIG. 1, the power feed method referred to here is first a container 2A containing an alkyl acrylate and the monofunctional monomer, an alkyl acrylate, the monofunctional monomer, and the polyfunctional monomer. A container 2B containing the monomer, a line 3A and a pump 4A for transferring the monomer component from the container 2A to the polymerization reactor 1, and a line 3B and a pump for transferring the monomer component from the container 2B to the container 2A 4B is prepared. Next, the alkyl acrylate and monofunctional monomer contained in the container 2A are transferred to the polymerization reactor 1 by the pump 4A through the line 3A, and the alkyl acrylate, monofunctional monomer, multi-functional monomer contained in the container 2B are transferred. The functional monomer is transferred to the container 2A by the pump 4B through the line 3B. Here, the alkyl acrylate and monofunctional monomer contained in the container 2A and the alkyl acrylate, monofunctional monomer and polyfunctional monomer transferred from the container 2B are contained in the container 2A. Mixed. In addition, it can be made to mix uniformly by stirring the container 2A in this case. Subsequently, the mixed liquid of alkyl acrylate, monofunctional monomer and polyfunctional monomer contained in the container 2A is transferred to the polymerization reactor 1 by the pump 4A through the line 3A, and the acrylic contained in the container 2B. The acid alkyl, monofunctional monomer, and polyfunctional monomer are transferred to the container 2A by the pump 4B through the line 3B. By repeating such an operation, the polyfunctional monomer part by weight in the mixed solution in the container 2A is gradually increased, and accordingly, the polyfunctional monomer part by weight transferred to the polymerization reactor 1 is also gradually increased. Therefore, it is possible to polymerize them while continuously increasing the weight parts of the polyfunctional monomer. The power feed method in the case where the monofunctional monomer is added to the container 2A and the container 2B has been described, but the present invention is not limited thereto. You may superpose | polymerize, you may superpose | polymerize without putting in either.

Next, in order to form the hard polymer layer (B) outside the elastic polymer layer (A), for example, a raw material constituting the hard polymer layer (B) (outer layer) in latex containing the polymer particles. An alkyl methacrylate, a monofunctional monomer having one radical-polymerizable double bond and / or a polyfunctional monomer having two or more radical-polymerizable double bonds, if necessary. These are polymerized. Thereby, the hard polymer layer (B) is formed in close contact with the outside of the elastic polymer layer (A), and a latex containing polymer particles having a two-layer structure can be obtained.
When a hard polymer layer is further formed on the outside of the hard polymer layer (B), the latex containing the polymer particles having the two-layer structure is used as a raw material for further forming the hard polymer layer. A monomer may be added for polymerization.

  Examples of the aqueous medium include water and a mixed solvent of water and a water-miscible solvent. The aqueous medium is preferably added all at once, in a divided manner or continuously so as to have a ratio of about 50 to 300 parts by weight with respect to 100 parts by weight of the total amount of each monomer as a raw material for the multilayer polymer particles.

  The emulsifier is not particularly limited, and examples thereof include an anionic emulsifier. Examples of the anionic emulsifier include linear or branched sodium alkylbenzene sulfonate such as sodium dodecylbenzene sulfonate. The emulsifier is preferably added in a lump, divided or continuously so as to have a ratio of about 0.01 to 5 parts by weight with respect to 100 parts by weight of the total amount of each monomer as a raw material of the multilayer polymer particles. .

  Examples of the polymerization initiator include persulfuric acid compounds such as potassium persulfate and ammonium persulfate. The polymerization initiator is added all at once, divided or continuously so that the ratio is about 0.01 to 1 part by weight with respect to 100 parts by weight of the total amount of each monomer as the raw material of the multilayer polymer particles. Is preferred. Moreover, you may use pH adjusters, such as sodium carbonate, as needed. The polymerization temperature is usually about 60 to 90 ° C.

In order to control the molecular weights of the elastic polymer layer (A) and the hard polymer layer (B), a known chain transfer agent can be used.
Examples of such chain transfer agents include primary, secondary and tertiary mercaptans having phenyl groups or substituted alkyl groups such as methyl mercaptan, ethyl mercaptan, n-butyl mercaptan, sec-dodecyl mercaptan, t-butyl mercaptan, and phenyl. Aromatic mercaptans such as mercaptans, thioglycolic acid and its esters, ethylene glycol and the like can be mentioned.

Further, the particle diameter of the multilayer polymer particles can be adjusted by adjusting the amount of the emulsifier added and the amount of each monomer used. The particle diameter is a weight average particle diameter of 30 to 200 nm, preferably 50 to 150 nm, and more preferably 60 to 120 nm. If it is less than 30 nm, sufficient elongation may not be obtained in a film-like methacrylic resin composition containing the particles. On the other hand, when it exceeds 200 nm, sufficient stress whitening resistance and transparency may not be obtained in a film-like methacrylic resin composition containing the particles.
In the multilayer polymer particle of the present invention, the diameter of the elastic polymer layer (A) in the central part when the central part is the elastic polymer layer (A) is not particularly limited, but is a weight average particle diameter, It is preferable that it is 10-120 nm.

Thus, a latex containing the multilayer polymer particles of the present invention can be obtained. As a method of recovering the multilayer polymer particles from this latex, a conventionally known method can be employed, for example, a method of coagulating by salting out, aciding out, freezing, etc., followed by filtration and then washing, The method of collect | recovering by a spray-drying process is mentioned.
The particle diameter of the multilayer polymer particles and the particle diameter of each layer can be adjusted by adjusting the amount of monomer components constituting each layer, the amount of emulsifier used at that time, and the like.

  The multilayer polymer particles of the present invention can be used alone after being formed into a film, but like a film of the present invention described later, a methacrylic resin composition mixed with a methacrylic resin is formed into a film. It is preferably used.

[Methacrylic resin composition]
The methacrylic resin composition of the present invention includes the multilayer polymer particles of the present invention described above and a methacrylic resin (C). At this time, the content ratio of both is normally multilayer polymer particles: methacrylic resin (C) (weight ratio) = 1: 99 to 99: 1. Preferably, multilayer polymer particles: methacrylic resin (C) (weight ratio) = 20: 80 to 80:20.

The methacrylic resin (C) contains an alkyl methacrylate in a range of 70 wt% to 100 wt%, and a monomer copolymerizable with the alkyl methacrylate in an amount of 30 wt% or less. A (co) polymer obtained by polymerizing a good monomer component is preferred.
As alkyl methacrylate here, what has a C1-C8 alkyl group is used normally, for example, methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, methacrylic acid. Examples include cyclohexyl.
Examples of the monomer copolymerizable with alkyl methacrylate include acrylic acid esters such as methyl acrylate, ethyl acrylate, butyl acrylate, and cyclohexyl acrylate; aromatic vinyl such as styrene. Compound; vinylcyan compounds such as acrylonitrile are listed. In addition, when transparency is required for the methacrylic resin composition to be obtained, each monomer constituting the multilayer polymer particle is made so that the refractive indexes of the multilayer polymer particle and the methacrylic resin are substantially the same. It is preferable to select the type in consideration.
The methacrylic resin (C) can be obtained, for example, by polymerizing the monomer component by a conventionally known method such as bulk polymerization, suspension polymerization, emulsion polymerization, or solution polymerization.

The methacrylic resin composition of the present invention can be obtained by mixing the multilayer polymer particles and the methacrylic resin (C) and subjecting to processing such as molding as necessary.
For mixing the multilayer polymer particles and the methacrylic resin (C), a conventionally known method such as a kneading machine, a method of melt kneading with a single screw extruder or a twin screw extruder can be employed.

  In the methacrylic resin composition of the present invention, if necessary, additives such as an anti-sticking agent, an ultraviolet absorber, a lubricant, an antioxidant, a plasticizer, an antistatic agent, and a dye do not impair the effects of the present invention. You may make it contain in the range. Among these, ultraviolet absorbers are preferably used for improving weather resistance. Only one type of additive may be used, or two or more types may be used. In addition, when an additive is included in the methacrylic resin composition, it may be added during the polymerization of the multilayer polymer particles, or may be added during mixing of the multilayer polymer particles and the methacrylic resin or during subsequent processing. May be.

Examples of the UV absorber include commonly used benzotriazole UV absorbers, 2-hydroxybenzophenone UV absorbers, and salicylic acid phenyl ester UV absorbers.
Specific examples of the benzotriazole ultraviolet absorber include 2,2′-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazol-2-yl) phenol], 2- (5-methyl-2-hydroxyphenyl) -2H-benzotriazole, 2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole, 2- (3 , 5-Di-tert-butyl-2-hydroxyphenyl) -2H-benzotriazole, 2- (3-tert-butyl-5-methyl-2-hydroxyphenyl) -5-chloro-2H-benzotriazole, 2- (3,5-di-tert-butyl-2-hydroxyphenyl) -5-chloro-2H-benzotriazole, 2- (3,5-di-tert-amino 2-hydroxyphenyl) -2H- benzotriazole, 2- (2'-hydroxy-5'-tert-octylphenyl) -2H- benzotriazole.
Specific examples of the 2-hydroxybenzophenone ultraviolet absorber include 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octyloxybenzophenone, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxy- Examples include 4'-chlorobenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone.
Specific examples of salicylic acid phenyl ester ultraviolet absorbers include p-tert-butylphenyl salicylic acid ester and p-octylphenyl salicylic acid ester.
These ultraviolet absorbers may be used alone or in combination of two or more. When the ultraviolet absorber is contained, the content thereof is usually 0.1% by weight or more, preferably 0.3% by weight or more and 2% by weight or less with respect to the total amount of the methacrylic resin composition. Good.

〔the film〕
The film of this invention consists of the methacryl resin composition of this invention mentioned above.
Such a film of the present invention can be produced by a film forming method such as a melt casting method, a melt extrusion method such as a T-die method or an inflation method, or a calendar method. Among these, the method of forming a film by bringing at least one surface of a film-like product obtained by melt-extruding the methacrylic resin composition from a T die, for example, into contact with a roll or a belt is preferable in that a film having good surface properties can be obtained. . In particular, from the viewpoint of improving the surface smoothness and surface gloss of the film, a method of forming a film by bringing both surfaces of a film-like product obtained by melt extrusion molding the methacrylic resin composition into contact with the roll surface or belt surface. Is preferred.

The film of the present invention may be colored.
As a coloring method, for example, a method in which a pigment or a dye is contained in the methacrylic resin composition itself to color the resin composition itself before film formation, or a film made of a methacrylic resin composition in a liquid in which the dye is dispersed is used. Examples of the coloring method include soaking and coloring, but are not particularly limited.
The film of the present invention is provided with a design layer formed by printing a pattern or the like on at least one surface of the film made of the methacrylic resin composition or by providing a colored layer. Also good. Such a design layer is preferably applied to the side in contact with the base material constituting the interior wall material in order to give a deep appearance.

The film of the present invention is obtained by laminating at least one layer made of a thermoplastic resin other than the methacrylic resin (hereinafter referred to as “thermoplastic resin layer”) on one side of the film made of the methacrylic resin composition. There may be. At this time, as described above, when a design layer such as printing or coloring is provided on one side of the film made of the methacrylic resin composition, the thermoplastic resin layer is laminated on the side on which the design layer is provided. Is good. The thermoplastic resin layer may be one layer or two or more layers. Moreover, when there are two or more thermoplastic resin layers, a part of the layers is preferably a design layer.
Examples of the thermoplastic resin other than the methacrylic resin forming the thermoplastic resin layer include, for example, polycarbonate resin, polyethylene terephthalate resin, polyethylene resin, polypropylene resin, polystyrene resin, polyvinyl chloride resin, and methacrylic resin composition. (Meth) acrylic resins other than methacrylic resins, ABS (acrylonitrile-butadiene-styrene copolymer) resins, and the like. Among these, ABS resin is particularly preferable.

The lamination integral molding method when laminating the thermoplastic resin layer on the film made of the methacrylic resin composition is not particularly limited, for example, the methacrylic resin composition and another thermoplastic resin, Separately forming into a film and laminating continuously between heated rolls, thermocompression using a press, laminating simultaneously with pressure air or vacuum forming, laminating via an adhesive layer (wet lamination) ), A method of laminating one preformed resin film with another resin melt-extruded from a T-die, and the like. In adopting these methods, if necessary, the film made of the methacrylic resin composition formed into a film is subjected to corona treatment or the like on the surface on which the thermoplastic resin layer is bonded. Or an adhesive layer may be provided.
In addition, when the other thermoplastic resin is formed into a film in advance, for example, when the other thermoplastic resin is a resin highly compatible with a methacrylic resin composition such as a polyvinyl chloride resin, The molded film may be directly laminated with the film made of the methacrylic resin composition. When the molded film is a resin incompatible with the methacrylic resin composition such as polyolefin resin, the molded film is dry laminated. What is necessary is just to laminate | stack with the film which consists of the said methacrylic resin composition through an adhesive agent by methods, such as.

For example, the film of the present invention obtained by laminating a colored thermoplastic resin layer on one side of a film made of a colorless and transparent methacrylic resin composition has a base of an interior wall material on the colored surface (thermoplastic resin layer side). If the material is pasted and combined, an excellent decorative member exhibiting a deep colored state will be obtained.
The thickness of the film of the present invention is not particularly limited, but is usually 0.03 to 0.5 mm, preferably 0.05 to 0.15 mm.
Such a film of the present invention can be suitably used, for example, for interior materials for automobiles, exterior materials for home appliances, construction materials (exterior), and the like.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, this invention is not limited only to a following example. In the following, “parts” and “%” mean “parts by weight” and “% by weight” unless otherwise specified.

Example 1
(Production of multilayer polymer particles)
First, a container 2A containing the following monomer raw material (A), a container 2B containing the following monomer raw material (A) in a 5 L glass reactor 1, and a single amount from the container 2A to the polymerization reactor 1 A line 3A and a pump 4A for transferring body components and a line 3B and a pump 4B for transferring monomer components from the container 2B to the container 2A were prepared. Next, the whole amount of the following aqueous medium raw material (c) was put into the polymerization reactor, and the temperature was raised to 80 ° C. with stirring in a nitrogen atmosphere.
Thereafter, the total amount of the monomer raw material (a) placed in the container 2A and the monomer raw material (a) placed in the container 2B is taken as 100 parts, and the monomer component is added from the container 2A to the polymerization reactor by 0.29. And the monomer component is transferred from the container 2B to the container 2A through the line 3B through the line 3B at a speed of 0.14 parts / minute. Monomer components were supplied.
Subsequently, the mixture is aged for 45 minutes at the same temperature with stirring, and is formed of only an elastic polymer layer (A) that continuously changes from the center of the particle to the outside toward a polymerization composition having a high allyl methacrylate ratio. A latex containing coalesced particles was obtained. Then, after adding the following additional initiator raw material (d) to the obtained latex at the same temperature and stirring, the raw material (e) for the hard polymer layer (B) below was added for 60 minutes at the same temperature. By continuously adding and aging at the same temperature for 45 minutes with continuous stirring, the elastic polymer layer (A) was used as an inner layer, and a hard polymer layer (B) serving as an outer layer in close contact with the outside was provided. A latex containing bilayer polymer particles was obtained. In addition, about the latex containing the polymer particle which consists only of an elastic polymer layer (A), and the latex containing the obtained two-layer polymer particle, the weight average particle diameter of the polymer particle contained in each latex is concentrated. When measured using a system particle size analyzer (“FPAR-1000” manufactured by Otsuka Electronics Co., Ltd.), they were 58 nm and 82 nm, respectively.

<Monomer raw material of elastic polymer layer (A) (A)>
Butyl acrylate 5.22 parts Methyl methacrylate 2.26 parts Styrene 1.09 parts <Monomer raw material of elastic polymer layer (A) (I)>
Butyl acrylate 5.22 parts Methyl methacrylate 2.26 parts Styrene 1.09 parts Allyl methacrylate 0.27 parts <Aqueous medium raw material (U)>
Ion-exchanged water 64.8 parts Sodium carbonate 0.04 parts Sodium dodecylbenzenesulfonate 0.16 parts Potassium persulfate 0.013 parts <Additional initiator raw material (E)>
Sodium dodecylbenzenesulfonate 0.16 parts Potassium persulfate 0.013 parts <Raw polymer layer (B) raw material (e)>
Methyl methacrylate 15.65 parts Methyl acrylate 1.74 parts

  Next, after the latex containing the obtained bilayer polymer particles is cooled and aggregated by cooling at −20 ° C. for 24 hours, the aggregate is melted and the obtained melt is filtered to form a bilayer. Polymer particles were isolated. Next, the isolated two-layer polymer particles were subjected to the operation of washing by filtration after being poured into ion-exchanged water 20 times by weight and then filtered, and then the temperature was increased to 60 ° C. It dried with the set vacuum dryer, and obtained the powdery bilayer polymer particle which is the multilayer polymer particle of this invention.

[Production of methacrylic resin composition and production of film]
50 parts of a pellet-like methacrylic resin obtained by bulk polymerization of a monomer component consisting of 95% methyl methacrylate and 5% methyl acrylate, and powdery two-layer polymer particles obtained above 50 parts was mixed with a super mixer and melt kneaded with a twin screw extruder to obtain pellets of a methacrylic resin composition.
Next, the obtained pellets were melted using a single screw extruder (manufactured by Toyo Seiki Co., Ltd.) with a diameter of 20 mm and extruded through a T-shaped die having a set temperature of 260 ° C., both sides were completely applied to two polishing rolls. By cooling so as to be in contact with the film, a film having a thickness of 80 μm made of a methacrylic resin composition was obtained.
The resulting film was evaluated for stress whitening and elongation at the time of tensile fracture by the following methods. The results are shown in Table 1.

<Evaluation of stress whitening>
The obtained film (thickness: 80 μm) was used as a sample, and this was placed on a sample holder of a push-up testing machine (“LF-Plus Universal Test Machine” manufactured by LLOYD INSTRUMENTS LTD.) On two stainless steel plates with 15 mmφ holes. It was fixed horizontally in a state of being sandwiched between. Then, in a 23 ° C. atmosphere, a 10 mmφ dart having a hemispherical tip was pushed down 5 mm downward from the film surface at the center of the hole in the stainless steel plate at a speed of 1200 mm / min. At this time, the stress-whitened state of the film deformed into a hemisphere was visually observed, and was determined to have 5 levels according to the following criteria. In addition, this test was performed 5 times and the average value of 5 determination levels was calculated | required.
Level 0: No whitening is observed.
Level 1: Extremely thin and whitening is observed. (Almost no whitening.)
Level 2: Light whitening is observed. (Slightly whitened.)
Level 3: Whitening is observed.
Level 4: Remarkable whitening is observed.

<Evaluation of elongation at tensile break>
A strip-shaped sample having a width of 10 mm is cut out from the obtained film (thickness 80 μm), and this is used to set a chuck interval of 90 mm and pull using a universal material testing machine (“1122RF55” manufactured by INSTRON). The elongation (%) at tensile fracture was measured at 23 ° C. with a speed of 50 mm / min. It can be said that the higher this value is, the better the elongation is.

(Example 2)
First, a container 2A containing the following monomer raw material (A), a container 2B containing the following monomer raw material (A) in a 5 L glass reactor 1, and a single amount from the container 2A to the polymerization reactor 1 A line 3A and a pump 4A for transferring body components and a line 3B and a pump 4B for transferring monomer components from the container 2B to the container 2A were prepared. Next, the whole amount of the following aqueous medium raw material (c) was put into the polymerization reactor, and the temperature was raised to 80 ° C. with stirring in a nitrogen atmosphere.
Thereafter, the monomer component is transferred from the container 2A to the polymerization reactor by the pump 4A through the line 3A at a rate of 0.26 parts / minute, and the monomer component is transferred from the container 2B to the container 2A at 0.13 parts / minute. The monomer component was fed in 87 minutes in total by the pump 4B through the line 3B.
Subsequently, the mixture is aged for 45 minutes at the same temperature with stirring, and is formed of only an elastic polymer layer (A) that continuously changes from the center of the particle to the outside toward a polymerization composition having a high allyl methacrylate ratio. A latex containing coalesced particles was obtained. Then, after adding the following additional initiator raw material (d) to the obtained latex at the same temperature and stirring, the raw material (e) for the hard polymer layer (B) below was added at the same temperature for 45 minutes. By continuously adding and aging at the same temperature for 45 minutes with continuous stirring, the elastic polymer layer (A) was used as an inner layer, and a hard polymer layer (B) serving as an outer layer in close contact with the outside was provided. A latex containing bilayer polymer particles was obtained. In addition, about the latex containing the polymer particle which consists only of an elastic polymer layer (A), and the latex containing the obtained two-layer polymer particle, the weight average particle diameter of the polymer particle contained in each latex is concentrated. It was 73 nm and 92 nm, respectively, when measured using a system particle size analyzer (“FPAR-1000” manufactured by Otsuka Electronics Co., Ltd.).

<Monomer raw material of elastic polymer layer (A) (A)>
Butyl acrylate 6.80 parts Methyl methacrylate 2.82 parts Styrene 1.42 parts <Monomer raw material of elastic polymer layer (A) (I)>
Butyl acrylate 6.80 parts Methyl methacrylate 2.82 parts Styrene 1.42 parts Allyl methacrylate 0.57 parts <Aqueous medium raw material (U)>
Ion-exchanged water 64.8 parts Sodium carbonate 0.04 parts Sodium dodecylbenzenesulfonate 0.14 parts Potassium persulfate 0.012 parts <Additional initiator raw material (E)>
Sodium dodecylbenzenesulfonate 0.11 part Potassium persulfate 0.012 part <Raw polymer layer (B) raw material (e)>
Methyl methacrylate 10.99 parts Methyl acrylate 1.22 parts

  Next, from the latex containing the obtained bilayer polymer particles, the bilayer polymer particles are isolated by the same operation as in Example 1, washed and dried in the same manner as in Example 1, and the Powdery two-layer polymer particles, which are multilayer polymer particles, were obtained.

[Production of methacrylic resin composition and production of film]
A methacrylic resin composition pellet was obtained in the same manner as in Example 1 except that the powdery two-layer polymer particles obtained above were used.
Next, a film having a thickness of 80 μm made of a methacrylic resin composition was obtained by the same operation as in Example 1 using the obtained pellets.
Evaluation of stress whitening property and elongation at the time of tensile fracture of the obtained film was evaluated in the same manner as in Example 1, and the results are shown in Table 1.

(Comparative Example 1)
First, the entire amount of the following aqueous medium raw material (c) was put into a 5 L glass reactor 1 and heated to 80 ° C. with stirring in a nitrogen atmosphere.
Thereafter, the monomer raw material [(A) + (I)] component of the following elastic polymer layer (A) was supplied to the polymerization reactor at a rate of 0.29 parts / minute in a total of 60 minutes.
Subsequently, the mixture was aged at the same temperature for 45 minutes while stirring to obtain a latex containing polymer particles consisting only of the elastic polymer layer (A) having a uniform allyl methacrylate ratio within the particles. Next, after adding the following additional initiator raw material (D) to the obtained latex at the same temperature and stirring, the following raw material (O) of the hard polymer layer (B) below was applied for 60 minutes at the same temperature. The elastic polymer layer (A) is used as an inner layer by aging for 45 minutes at the same temperature with continuous stirring, and a hard polymer layer (B) that is in close contact with the outer side is provided. A latex containing two-layer polymer particles was obtained. In addition, about the latex containing the polymer particle which consists only of an elastic polymer layer (A), and the latex containing the obtained two-layer polymer particle, the weight average particle diameter of the polymer particle contained in each latex is concentrated. When measured using a system particle size analyzer ("FPAR-1000" manufactured by Otsuka Electronics Co., Ltd.), they were 56 nm and 83 nm, respectively.

<Monomer material of elastic polymer layer (A) (A) + (I)>
Butyl acrylate 10.44 parts Methyl methacrylate 4.52 parts Styrene 2.18 parts Allyl methacrylate 0.27 parts <Aqueous medium raw material (U)>
Ion-exchanged water 64.8 parts Sodium carbonate 0.04 parts Sodium dodecylbenzenesulfonate 0.16 parts Potassium persulfate 0.013 parts <Additional initiator raw material (E)>
Sodium dodecylbenzenesulfonate 0.16 parts Potassium persulfate 0.013 parts <Raw polymer layer (B) raw material (e)>
Methyl methacrylate 15.65 parts Methyl acrylate 1.74 parts

  Next, from the latex containing the obtained bilayer polymer particles, the bilayer polymer particles are isolated by the same operation as in Example 1, washed and dried in the same manner as in Example 1, and the Powdery two-layer polymer particles, which are multilayer polymer particles, were obtained.

[Production of methacrylic resin composition and production of film]
A methacrylic resin composition pellet was obtained in the same manner as in Example 1 except that the powdery two-layer polymer particles obtained above were used.
Next, a film having a thickness of 80 μm made of a methacrylic resin composition was obtained by the same operation as in Example 1 using the obtained pellets.
Evaluation of stress whitening property and elongation at the time of tensile fracture of the obtained film was evaluated in the same manner as in Example 1, and the results are shown in Table 1.

(Comparative Example 2)
First, the entire amount of the following aqueous medium raw material (c) was put into a 5 L glass reactor 1 and heated to 80 ° C. with stirring in a nitrogen atmosphere.
Thereafter, the following monomer raw material [(A) + (I)] component of the following elastic polymer layer (A) was supplied to the polymerization reactor at a rate of 0.29 parts / min for a total of 87 minutes.
Subsequently, the mixture was aged at the same temperature for 45 minutes while stirring to obtain a latex containing polymer particles consisting only of the elastic polymer layer (A) having a uniform allyl methacrylate ratio within the particles. Then, after adding the following additional initiator raw material (d) to the obtained latex at the same temperature and stirring, the raw material (e) for the hard polymer layer (B) below was added at the same temperature for 45 minutes. By continuously adding and aging at the same temperature for 45 minutes with continuous stirring, the elastic polymer layer (A) was used as an inner layer, and a hard polymer layer (B) serving as an outer layer in close contact with the outside was provided. A latex containing bilayer polymer particles was obtained. In addition, about the latex containing the polymer particle which consists only of an elastic polymer layer (A), and the latex containing the obtained two-layer polymer particle, the weight average particle diameter of the polymer particle contained in each latex is concentrated. It was 70 nm and 90 nm, respectively, when measured using a system particle size analyzer (“FPAR-1000” manufactured by Otsuka Electronics Co., Ltd.).

<Monomer material of elastic polymer layer (A) (A) + (I)>
Butyl acrylate 13.60 parts Methyl methacrylate 5.64 parts Styrene 2.84 parts Allyl methacrylate 0.57 parts <Aqueous medium raw material (U)>
Ion-exchanged water 64.8 parts Sodium carbonate 0.04 parts Sodium dodecylbenzenesulfonate 0.14 parts Potassium persulfate 0.012 parts <Additional initiator raw material (E)>
Sodium dodecylbenzenesulfonate 0.11 part Potassium persulfate 0.012 part <Raw polymer layer (B) raw material (e)>
Methyl methacrylate 10.99 parts Methyl acrylate 1.22 parts

  Next, from the latex containing the obtained bilayer polymer particles, the bilayer polymer particles are isolated by the same operation as in Example 1, washed and dried in the same manner as in Example 1, and the Powdery two-layer polymer particles, which are multilayer polymer particles, were obtained.

[Production of methacrylic resin composition and production of film]
A methacrylic resin composition pellet was obtained in the same manner as in Example 1 except that the powdery two-layer polymer particles obtained above were used.
Next, a film having a thickness of 80 μm made of a methacrylic resin composition was obtained by the same operation as in Example 1 using the obtained pellets.
Evaluation of stress whitening property and elongation at the time of tensile fracture of the obtained film was evaluated in the same manner as in Example 1, and the results are shown in Table 1.

(Comparative Example 3)
The same operation as in Example 1 except that the monomer raw material (a) of the elastic polymer layer (A) was put in the container 2B and the monomer raw material (b) of the elastic polymer layer (A) was put in the container 2A. As a result, a latex containing two-layer polymer particles provided with an elastic polymer layer (A) as an inner layer and a hard polymer layer (B) as an outer layer in close contact with the outer layer was obtained. In addition, about the latex containing the polymer particle which consists only of an elastic polymer layer (A), and the latex containing the obtained two-layer polymer particle, the weight average particle diameter of the polymer particle contained in each latex is concentrated. It was 71 nm and 91 nm, respectively, when measured using a system particle size analyzer (“FPAR-1000” manufactured by Otsuka Electronics Co., Ltd.).

  Next, from the latex containing the obtained bilayer polymer particles, the bilayer polymer particles are isolated by the same operation as in Example 1, washed and dried in the same manner as in Example 1, and the Powdery two-layer polymer particles, which are multilayer polymer particles, were obtained.

[Production of methacrylic resin composition and production of film]
A methacrylic resin composition pellet was obtained in the same manner as in Example 1 except that the powdery two-layer polymer particles obtained above were used.
Next, a film having a thickness of 80 μm made of a methacrylic resin composition was obtained by the same operation as in Example 1 using the obtained pellets.
Evaluation of stress whitening property and elongation at the time of tensile fracture of the obtained film was evaluated in the same manner as in Example 1, and the results are shown in Table 1.

1 Polymerization reactor 2A, 2B Container 3A, 3B Line 4A, 4B Pump

Claims (5)

Multilayer polymer particles comprising the following elastic polymer layer (A) and hard polymer layer (B) in this order from the center of the particle toward the outer surface.
Elastic polymer layer (A): 50-99.9 parts by weight of alkyl acrylate, 0-49.9 parts by weight of monofunctional monomer having one double bond capable of radical polymerization, and double radical capable of radical polymerization A polymer layer obtained by polymerizing 0.1 to 10 parts by weight of a polyfunctional monomer having two or more bonds, and polymerizing while continuously increasing the weight part of the polyfunctional monomer from the inside.
Hard polymer layer (B): 50-100 parts by weight of alkyl methacrylate, 0-50 parts by weight of monofunctional monomer having one radical polymerizable double bond, and two radical polymerizable double bonds A polymer layer formed by polymerizing 0 to 3 parts by weight of the polyfunctional monomer.   The multilayer polymer particle according to claim 1, wherein the elastic polymer layer (A) is 30 to 95 parts by weight with respect to 100 parts by weight of the total of the elastic polymer layer (A) and the hard polymer layer (B).   A methacrylic resin composition comprising 1 to 99 parts by weight of the multilayer polymer particles according to claim 1 or 2 and 99 to 1 part by weight of a methacrylic resin (C).   The methacrylic resin (C) is a methacrylic resin composition according to claim 3, wherein 70 to 100 parts by weight of an alkyl methacrylate and 0 to 30 parts by weight of a monomer copolymerizable therewith are polymerized.   A film comprising the methacrylic resin composition according to claim 3 or 4.

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