Composition and resin composition

Abstract

To provide a composition which can suppress bleed-out of a phosphate ester and has the effect of improving impact resistance and flame retardancy, and a resin composition which has good moldability and can achieve both excellent impact strength and flame retardancy.SOLUTION: The composition contains a phosphate ester (B) which is present in an impregnation state in a polymer (A) having a core part containing a rubbery polymer and a graft part containing a constituent unit derived from a (meth)acylate. The resin composition containing the composition and a thermoplastic resin exhibits good moldability and achieves both excellent impact strength and flame retardancy.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a composition, particularly a composition in which a graft copolymer containing a rubber polymer is impregnated with a phosphoric acid ester, and a resin composition using said composition. [Background technology]

[0002] Graft copolymers, in which vinyl monomers are graft-polymerized onto rubbery polymers, can be dispersed in a wide variety of resins while maintaining a predetermined rubber particle size and rubber structure, and are therefore suitable for use as resin modifiers in resins that require impact strength.

[0003] Incidentally, flame retardants are also widely used as resin modifiers, and phosphate esters, which are non-halogen liquid flame retardants, are widely used. Patent Document 1 discloses a resin composition in which triphenyl phosphate, which is a phosphoric acid ester, and melamine cyanurate are blended with polyalkylene terephthalate. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 3-281652 Summary of the Invention [Problem to be solved by the invention]

[0005] However, phosphate esters have low compatibility with crystalline resins such as polyethylene, polypropylene, polyethylene terephthalate, polybutylene terephthalate, polyamide, etc. The inventors of the present invention have found that when a phosphate ester is blended as a flame retardant with a crystalline resin, the phosphate ester bleeds out onto the resin surface, which not only reduces flame retardancy but also makes it difficult to sufficiently knead pellets of the resin composition, making molding itself difficult.

[0006] A primary object of the present invention is to provide a composition that can suppress bleed-out of a phosphate ester and has the effect of improving impact resistance and flame retardancy, and a resin composition that has good moldability and can achieve both excellent impact strength and flame retardancy. [Means for solving the problem]

[0007] The present invention includes the following configurations. [1] A composition containing a polymer (A) and a phosphoric acid ester (B), The polymer (A) has a core portion containing a rubber polymer and a graft portion containing a structural unit derived from a (meth)acrylate, The composition, wherein the phosphate ester (B) is present in a state of being impregnated in the polymer (A). [2] The composition according to [1], wherein the phosphate ester (B) includes a phosphate ester (B1) having a viscosity at 25°C of 100 mPa·s or less. [3] The composition according to [2], wherein the phosphate ester (B1) has a freezing point of 0°C or lower. [4] The composition according to any one of [1] to [3], wherein the content of the (meth)acrylate-derived structural units in the graft portion is 65% by mass or more relative to the total structural units (100% by mass) of the graft portion. [5] The composition according to any one of [1] to [4], wherein the rubbery polymer includes at least one selected from the group consisting of butadiene rubber, silicone rubber, and acrylic rubber. [6] The composition according to any one of [1] to [5], wherein the graft moiety further contains a structural unit derived from an aromatic vinyl monomer. [7] The composition according to any one of [1] to [6], which is a resin modifier. [8] A resin composition comprising the composition according to any one of [1] to [7] and a thermoplastic resin. [9] The resin composition according to [8], wherein the thermoplastic resin is a crystalline resin.

[10] The resin composition according to [8] or [9], wherein the thermoplastic resin is a polyester.

[11] The resin composition according to

[10] , wherein the polyester is polybutylene terephthalate. [Effects of the Invention]

[0008] According to the present invention, there are provided a composition that can suppress bleed-out of a phosphate ester and has the effect of improving impact resistance and flame retardancy, and a resin composition that has good moldability and can achieve both excellent impact strength and flame retardancy. DETAILED DESCRIPTION OF THE INVENTION

[0009] As used herein, the following definitions apply: The term "structural unit" refers to a structural unit derived from a monomer, i.e., a structural unit formed by polymerizing a monomer, or a structural unit in which a portion of the structural unit is converted into a different structure by treating the polymer. "(Meth)acrylate" is a general term for acrylate and methacrylate. "(Meth)acrylic" is a general term for acrylic and methacrylic. The "glass transition temperature" is a value measured by differential scanning calorimetry (DSC) according to a method in accordance with JIS K-7121-1987. A numerical range expressed by "to" means a numerical range that includes the numbers before and after the to as the lower and upper limits. The numerical ranges of the contents, various physical property values, and property values ​​disclosed in this specification can be arbitrarily combined with the lower and upper limits to form new numerical ranges.

[0010] <Composition> The composition according to the embodiment is a composition containing a polymer (A) and a phosphate ester (B), wherein the polymer (A) has a core portion containing a rubber polymer and a graft portion containing a structural unit derived from a (meth)acrylate, and the phosphate ester (B) is present in an impregnated state in the polymer (A). Compositions according to embodiments are particularly useful as resin modifiers that impart impact strength and flame retardancy.

[0011] [Polymer (A)] The polymer (A) is a graft copolymer having a core containing a rubber polymer and a graft portion containing a structural unit derived from (meth)acrylate, i.e., the polymer (A) is a graft polymer having a core-shell structure consisting of a core containing a rubber polymer and a graft portion forming a shell structure.

[0012] (Core part) The core contains a rubbery polymer, which means a polymer having a glass transition temperature of 0°C or lower. To have rubber elasticity, it is sufficient that the polymer has a crosslinked rubber structure. The crosslinked structure is not particularly limited, and may be chemically crosslinked or physically crosslinked. Of these, chemical crosslinking is preferred from the viewpoint of stability during molding. To have a chemically crosslinked structure, the polymer preferably contains structural units derived from a crosslinkable monomer, and more preferably contains 0.01% by mass or more of structural units derived from a crosslinkable monomer relative to the total mass of the polymer (100% by mass).

[0013] The rubber polymer preferably contains at least one selected from the group consisting of butadiene rubber, silicone rubber and acrylic rubber, and more preferably contains acrylic rubber, because it has a high effect of improving impact strength.

[0014] (1) Butadiene rubber The butadiene rubber may be, for example, a copolymer of 1,3-butadiene and one or more vinyl monomers copolymerizable with 1,3-butadiene. Examples of vinyl monomers copolymerizable with 1,3-butadiene include styrene, α-methylstyrene, vinyltoluene, etc. These vinyl monomers may be used alone or in combination of two or more.

[0015] The content of the 1,3-butadiene-derived structural units in the butadiene rubber is preferably 60% by mass or more, more preferably 65% ​​by mass or more, based on the total structural units of the butadiene rubber. When the content of the 1,3-butadiene-derived structural units is equal to or more than the lower limit, the effect of improving impact strength is further enhanced.

[0016] (2) Silicone rubber Examples of silicone rubbers include polymers containing organosiloxane units as constituent units, such as polyorganosiloxane rubbers and polyorganosiloxane composite rubbers. The polyorganosiloxane rubber is obtained by emulsion polymerization of an organosiloxane mixture (monomer component) containing an organosiloxane, a polyorganosiloxane graft crosslinking agent (hereinafter also referred to as "siloxane crosslinking agent"), and a siloxane oligomer having a terminal blocking group. If necessary, a polyorganosiloxane crosslinking agent (hereinafter also referred to as "siloxane crosslinking agent") may be used in the polyorganosiloxane rubber.

[0017] The organosiloxane may be either a chain organosiloxane or a cyclic organosiloxane, with cyclic organosiloxanes being preferred due to their high polymerization stability and high polymerization rate. As the cyclic organosiloxane, a cyclic organosiloxane having a 3- or greater ring is preferred, and a cyclic organosiloxane having a 3- to 6-membered ring is more preferred.

[0018] Examples of cyclic organosiloxanes include hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, trimethyltriphenylcyclotrisiloxane, tetramethyltetraphenylcyclotetrasiloxane, octaphenylcyclotetrasiloxane, etc. One type of cyclic organosiloxane may be used alone, or two or more types may be used in combination.

[0019] The siloxane crosslinking agent is preferably one that can bond with the organosiloxane via a siloxane bond and form a bond with the vinyl monomer. In consideration of reactivity with the organosiloxane, an alkoxysilane compound having a vinyl group is preferred. By using a siloxane crosslinking agent, it is possible to obtain a polyorganosiloxane having a functional group polymerizable with any vinyl monomer.

[0020] Examples of siloxane crosslinking agents include β-methacryloyloxyethyl dimethoxymethylsilane, γ-methacryloyloxypropyl methoxydimethylsilane, γ-methacryloyloxypropyl dimethoxymethylsilane, γ-methacryloyloxypropyl trimethoxysilane, γ-methacryloyloxypropyl ethoxydiethylsilane, γ-methacryloyloxypropyl diethoxymethylsilane, δ-methacryloyloxybutyl diethoxymethylsilane, vinylphenylethyl dimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-mercaptopropyl dimethoxymethylsilane, γ-mercaptopropyl methoxydimethylsilane, γ-mercaptopropyl diethoxymethylsilane, γ-mercaptopropyl ethoxydimethylsilane, γ-mercaptopropyl trimethoxysilane, etc. One type of siloxane crosslinking agent may be used alone, or two or more types may be used in combination.

[0021] The siloxane crosslinking agent preferably has three or four functional groups capable of bonding with organosiloxane. Examples of the siloxane crosslinking agent include trialkoxyalkylsilanes such as trimethoxymethylsilane; trialkoxyarylsilanes such as triethoxyphenylsilane; and tetraalkoxysilanes such as tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, and tetrabutoxysilane. One type of siloxane crosslinking agent may be used alone, or two or more types may be used in combination.

[0022] The siloxane oligomer having a terminal blocking group refers to a siloxane oligomer that has an alkyl group or the like at the end of the organosiloxane oligomer and terminates the polymerization of the polyorganosiloxane. Examples of siloxane oligomers having a terminal blocking group include hexamethyldisiloxane, 1,3-bis(3-glycidoxypropyl)tetramethyldisiloxane, 1,3-bis(3-aminopropyl)tetramethyldisiloxane, methoxytrimethylsilane, etc. These may be used alone or in combination of two or more.

[0023] The content of the organosiloxane-derived structural units in the polyorganosiloxane rubber is preferably 60 to 99.9 mass %, more preferably 70 to 99.9 mass %, based on the total mass of the polyorganosiloxane rubber. The content of the structural units derived from the siloxane crosslinking agent in the polyorganosiloxane rubber is preferably 0.1 to 10% by mass relative to the total mass of the polyorganosiloxane rubber. The content of the structural units derived from the siloxane crosslinking agent in the polyorganosiloxane rubber is preferably 0 to 30% by mass relative to the total mass of the polyorganosiloxane rubber.

[0024] The polyorganosiloxane composite rubber contains a polyorganosiloxane rubber and a vinyl polymer for composite rubber, and preferably contains a polyorganosiloxane rubber and a polyalkyl (meth)acrylate rubber.

[0025] The vinyl polymer for composite rubber can be obtained by polymerizing a vinyl monomer for composite rubber and, if necessary, a crosslinking monomer or an acrylic crosslinking agent. Examples of vinyl monomers for composite rubbers include alkyl acrylates such as methyl acrylate, ethyl acrylate, n-propyl acrylate, and n-butyl acrylate; alkyl methacrylates such as methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, and i-butyl methacrylate; aromatic vinyl monomers such as styrene and α-methylstyrene; and vinyl cyanide monomers such as acrylonitrile and methacrylonitrile. Among these, n-butyl acrylate is preferred because of its high impact strength improving effect. One type of vinyl monomer for composite rubber may be used alone, or two or more types may be used in combination.

[0026] The crosslinkable monomer is a polyfunctional monomer having two or more polymerizable unsaturated bonds. Specific examples include allyl methacrylate, triallyl cyanurate, triallyl isocyanurate, divinylbenzene, ethylene glycol dimethacrylate, propylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,4-butylene glycol dimethacrylate, 1,6-hexanediol diacrylate, and triallyl trimellitate. The crosslinkable monomer may be used alone or in combination of two or more.

[0027] Acrylic crosslinking agents are multifunctional monomers with two or more polymerizable unsaturated bonds of different reactivity. By having groups with different reactivities, they are incorporated into the composite rubber while preserving the unsaturated groups when polymerized with other components, enabling the formation of a graft copolymer. Examples include allyl methacrylate, triallyl cyanurate, and triallyl isocyanurate. One type of acrylic crosslinking agent may be used alone, or two or more types may be used in combination. The acrylic crosslinking agent has two or more polymerizable unsaturated bonds, similar to the crosslinkable monomer, and therefore also functions as a crosslinking agent.

[0028] The content of the polyorganosiloxane rubber in the polyorganosiloxane composite rubber is preferably 0.1 to 99.9 mass %, more preferably 5 to 99.9 mass %, and even more preferably 7 to 99.9 mass %, based on the total mass of the polyorganosiloxane composite rubber. The content of the structural units derived from the crosslinkable monomer in the polyorganosiloxane composite rubber is preferably 0 to 15 parts, more preferably 0.1 to 10 parts, per 100 parts by mass of the structural units derived from the vinyl monomer for the composite rubber. The content of the structural units derived from the acrylic crosslinking agent in the polyorganosiloxane composite rubber is preferably 0 to 15 parts, more preferably 0.1 to 10 parts, per 100 parts by mass of the structural units derived from the vinyl monomer for the composite rubber.

[0029] (3) Acrylic rubber Examples of the acrylic rubber include a homopolymer or copolymer of alkyl (meth)acrylate. Examples of alkyl (meth)acrylates include alkyl acrylates such as methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, ethoxyethoxyethyl acrylate, methoxytripropylene glycol acrylate, and 4-hydroxybutyl acrylate; and alkyl methacrylates such as hexyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, tridecyl methacrylate, and stearyl methacrylate. These alkyl (meth)acrylates may be used alone or in combination of two or more.

[0030] The acrylic rubber may contain a small amount of structural units derived from monomers other than alkyl (meth)acrylate. Examples of other monomers include aromatic alkenyl compounds such as styrene, α-methylstyrene, and vinyltoluene, vinyl cyanide compounds such as acrylonitrile and methacrylonitrile, and methacrylic group-modified silicones. These other monomers may be used alone or in combination of two or more.

[0031] The acrylic rubber may contain at least one of a crosslinking agent and a grafting agent, if necessary. Examples of the crosslinking agent include ethylene glycol dimethacrylate, propylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,4-butylene glycol dimethacrylate, divinylbenzene, polyfunctional methacrylic group-modified silicone, etc. One type of crosslinking agent may be used alone, or two or more types may be used in combination.

[0032] Examples of grafting agents include allyl methacrylate, triallyl cyanurate, and triallyl isocyanurate. Allyl methacrylate can also be used as a crosslinking agent. The grafting agents may be used alone or in combination of two or more.

[0033] The acrylic rubber is preferably an acrylic rubber whose main component is a structural unit derived from n-butyl acrylate, where "main component is a structural unit derived from n-butyl acrylate" means that the proportion of the structural units derived from n-butyl acrylate to the total structural units of the acrylic rubber is 50% by mass or more, preferably 70% by mass or more, and more preferably 90% by mass or more. One example is an acrylic rubber containing 0.1 to 3 parts by mass of structural units derived from allyl methacrylate per 100 parts by mass of structural units derived from n-butyl acrylate, and an acrylic rubber containing 0.1 to 0.7 parts by mass of structural units derived from allyl methacrylate per 100 parts by mass of structural units derived from n-butyl acrylate is preferred.

[0034] The content of the core portion in the polymer (A) is preferably 30% by mass or more, more preferably 40% by mass or more, and even more preferably 50% by mass or more, relative to the total mass (100% by mass) of the polymer (A), since this enhances the effect of imparting impact strength. Furthermore, the content of the core portion in the polymer (A) is preferably 99% by mass or less, more preferably 95% by mass or less, and even more preferably 90% by mass or less, relative to the total mass (100% by mass) of the polymer (A), since this improves the dispersibility of the composition in thermoplastic resins.

[0035] The glass transition temperature of the rubbery polymer constituting the core is typically 0° C. or lower, and is preferably −10° C. or lower, more preferably −20° C. or lower, because this enhances the effect of imparting impact strength. When the rubbery polymer has two or more glass transition temperatures, it is preferable that all of the glass transition temperatures are lower than the upper limit value.

[0036] The method for producing the rubbery polymer is not particularly limited, and the rubbery polymer can be produced by a known method, for example, emulsion polymerization, suspension polymerization, solution polymerization, interfacial polymerization between two phases, etc. Among these, emulsion polymerization is preferred because it is easy to introduce a graft moiety into the rubbery polymer. When producing a rubbery polymer by combining two or more monomer components, either a method of simultaneously polymerizing two or more monomer components or a method of polymerizing two or more monomer components in stages may be used.

[0037] As the emulsifier, an anionic emulsifier or a nonionic emulsifier is preferred. Examples of anionic emulsifiers include sodium alkylbenzenesulfonate, sodium alkyldiphenyletherdisulfonate, sodium alkylsulfate, sodium polyoxyethylene alkylsulfate, and sodium polyoxyethylene nonylphenylether sulfate. Examples of nonionic emulsifiers include polyoxyethylene alkyl ethers, polyoxyethylene alkylene alkyl ethers, polyoxyethylene distyrenated phenyl ethers, polyoxyethylene tribenzyl phenyl ethers, and polyoxyethylene polyoxypropylene glycols. The emulsifier may be used alone or in combination of two or more kinds.

[0038] The polymerization initiator used for the polymerization is not particularly limited, and any known polymerization initiator can be used, such as persulfates, peroxides, azo initiators, redox initiators in which persulfates are combined with a reducing agent, and redox initiators in which an organic peroxide is combined with a reducing agent. The polymerization initiator may be used alone or in combination of two or more kinds.

[0039] Examples of peroxides include inorganic peroxides such as hydrogen peroxide, potassium persulfate, and ammonium persulfate; and organic peroxides such as diisopropylbenzene hydroperoxide, p-menthane hydroperoxide, cumene hydroperoxide, t-butyl hydroperoxide, succinic acid peroxide, t-butyl peroxyneodecanoate, t-butyl peroxyneoheptanoate, t-butyl peroxypivalate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, and t-butylperoxy-2-ethylhexanoate. The peroxides may be used alone or in combination of two or more.

[0040] Examples of the azo initiator include oil-soluble azo initiators such as 2,2'-azobisisobutyronitrile, dimethyl 2,2'-azobis(2-methylpropionate), 2,2'-azobis(2,4-dimethylvaleronitrile), and 2,2'-azobis(2-butyronitrile); and water-soluble azo initiators such as 4,4'-azobis(4-cyanovaleric acid), 2,2'-azobis[N-(2-carboxymethyl)-2-methylpropionamidine]hydrate, 2,2'-azobis-(N,N'-dimethyleneisobutylamidine) dihydrochloride, and 2,2'-azobis[2-(2-imidazolin-2-yl)propane] dihydrochloride. The azo initiators may be used alone or in combination of two or more.

[0041] When an organic peroxide is combined with a reducing agent to form a redox initiator, it is preferable to use the above organic peroxide in combination with a reducing agent such as sodium formaldehyde sulfoxylate, L-ascorbic acid, fructose, dextrose, sorbose, or inositol, and ferrous sulfate·ethylenediaminetetraacetic acid disodium salt. The reducing agent may be used alone or in combination of two or more kinds.

[0042] The amount of emulsifier used is preferably 0.05 to 10 parts by mass, more preferably 0.1 to 5 parts by mass, even more preferably 0.5 to 5 parts by mass, and particularly preferably 1 to 2.5 parts by mass, relative to 100 parts by mass of the monomer components used in the rubber polymer. The rubber particle size can be adjusted to a desired value by adjusting the amount of emulsifier used. The amount of the polymerization initiator used is preferably 0.01 to 1 part by mass relative to 100 parts by mass of the monomer component used in the rubber polymer. When a peroxide is used as the polymerization initiator, the amount of the peroxide used is preferably, for example, 0.01 to 1 part by mass per 100 parts by mass of the monomer component used in the rubber polymer. From the viewpoint of outgassing resistance, the amount of the reducing agent used is preferably 0.01 to 1 part by mass per 100 parts by mass of the monomer component used in the rubber polymer.

[0043] The polymerization temperature is not particularly limited and can be set to, for example, 30 to 100°C. The polymerization time is not particularly limited and can be, for example, 3 to 30 hours.

[0044] (graft area) The graft portion of the polymer (A) contains a structural unit derived from a (meth)acrylate. As the (meth)acrylate, alkyl (meth)acrylate is preferred because it has excellent impregnation properties with the phosphate ester (B), alkyl (meth)acrylate having an alkyl group with 1 to 4 carbon atoms is more preferred, and methyl methacrylate is particularly preferred. Specific examples of alkyl (meth)acrylates other than methyl methacrylate include ethyl methacrylate, n-butyl methacrylate, methyl acrylate, and n-butyl acrylate. The (meth)acrylate may be used alone or in combination of two or more kinds.

[0045] The graft portion of the polymer (A) may contain, in addition to a structural unit derived from a (meth)acrylate, a structural unit derived from a monomer other than a (meth)acrylate. Examples of the other monomer include an aromatic vinyl monomer, a vinyl cyanide monomer, a (meth)acrylic group-modified silicone monomer, etc. These other monomers may be used alone or in combination of two or more.

[0046] Examples of aromatic vinyl monomers include styrene, alkyl-substituted styrenes (p-methylstyrene, m-methylstyrene, o-methylstyrene, 2,4-dimethylstyrene, 2,5-dimethylstyrene, 3,4-dimethylstyrene, 3,5-dimethylstyrene, p-ethylstyrene, m-ethylstyrene, o-ethylstyrene, etc.), alkyl-substituted isopropenylbenzenes (isopropenylbenzene (α-methylstyrene), isopropenyltoluene, isopropenylethylbenzene, isopropenylpropylbenzene, isopropenylbutylbenzene, isopropenylpentylbenzene, isopropenylhexylbenzene, isopropenioctylbenzene, etc.), and 1,1-diphenylethylene. Examples of vinyl cyanide monomers include acrylonitrile and methacrylonitrile.

[0047] Specific examples of the graft moiety include a graft moiety containing only structural units derived from (meth)acrylate, and a graft moiety containing structural units derived from (meth)acrylate and structural units derived from an aromatic vinyl monomer, and preferred are graft moieties containing only structural units derived from methyl methacrylate, and graft moieties containing structural units derived from methyl methacrylate and structural units derived from an aromatic vinyl monomer.

[0048] Because of the excellent impregnation property of the phosphate ester (B), the content of the (meth)acrylate-derived structural units in the graft portion is preferably 65% ​​by mass or more, more preferably 75% by mass or more, and even more preferably 85% by mass or more, based on the total structural units (100% by mass) constituting the graft portion. The upper limit of the content of the (meth)acrylate-derived structural units can be set to 100% by mass.

[0049] Because of the excellent impregnation property of the phosphate ester (B), the content of the methyl methacrylate-derived structural units in the graft portion is preferably 65% ​​by mass or more, more preferably 75% by mass or more, and even more preferably 85% by mass or more, based on the total structural units (100% by mass) constituting the graft portion. The upper limit of the content of the methyl methacrylate-derived structural units can be set to 100% by mass.

[0050] The content of structural units derived from other monomers in the graft portion is preferably 35% by mass or less, more preferably 25% by mass or less, even more preferably 15% by mass or less, and particularly preferably 5% by mass or less, relative to all structural units constituting the graft portion (100% by mass). The content of the aromatic vinyl monomer-derived structural units in the graft moiety is preferably 35% by mass or less, more preferably 25% by mass or less, even more preferably 15% by mass or less, and particularly preferably 5% by mass or less, based on the total structural units constituting the graft moiety (100% by mass). When the content of the aromatic vinyl monomer-derived structural units is equal to or less than the upper limit, the impregnation property of the phosphate ester (B) becomes better.

[0051] The content of the graft moiety in the polymer (A) is preferably 1% by mass or more, more preferably 5% by mass or more, and even more preferably 10% by mass or more, relative to the total mass (100% by mass) of the polymer (A), since this improves the dispersibility of the composition in the thermoplastic resin. Furthermore, the content of the graft moiety in the polymer (A) is preferably 70% by mass or less, more preferably 60% by mass or less, and even more preferably 50% by mass or less, relative to the total mass (100% by mass) of the polymer (A), since this further enhances the effect of imparting impact strength.

[0052] The content of the methyl methacrylate-derived structural units in the polymer (A) is preferably 15% by mass or more, more preferably 20% by mass or more, and even more preferably 25% by mass or more, relative to the total mass (100% by mass) of the polymer (A). The upper limit is preferably 80% by mass or less, more preferably 70% by mass or less, and even more preferably 60% by mass or less. When the content of the methyl methacrylate-derived structural units is equal to or greater than the lower limit, the impregnation of the phosphate ester (B) becomes more excellent, and the effect of suppressing bleed-out of the phosphate ester (B) when blended into a resin composition tends to be greater. When the content of the methyl methacrylate-derived structural units is equal to or less than the upper limit, the content of the rubbery polymer becomes relatively high, and the effect of improving impact strength tends to be greater.

[0053] The content of the (meth)acrylate-derived structural units in the polymer (A) is preferably 15% by mass or more, more preferably 20% by mass or more, and even more preferably 25% by mass or more, relative to the total mass (100% by mass) of the polymer (A). The upper limit is preferably 80% by mass or less, more preferably 70% by mass or less, and even more preferably 60% by mass or less. When the content of the (meth)acrylate-derived structural units is equal to or greater than the lower limit, the impregnation of the phosphate ester (B) becomes more excellent, and the effect of suppressing bleed-out of the phosphate ester (B) when blended into a resin composition tends to be greater. When the content of the (meth)acrylate-derived structural units is equal to or less than the upper limit, the content of the rubbery polymer becomes relatively high, and the effect of improving impact strength tends to be greater.

[0054] From the viewpoints of improving dispersibility in thermoplastic resins and preventing blocking, the glass transition temperature of the polymer constituting the graft moiety is preferably 30° C. or higher, more preferably 50° C. or higher, and even more preferably 60° C. or higher. Furthermore, in order to enhance the effect of imparting impact strength, the glass transition temperature of the polymer constituting the graft moiety is preferably 150° C. or lower, more preferably 140° C. or lower, and even more preferably 120° C. or lower.

[0055] In order to improve dispersibility in thermoplastic resins, the weight-average molecular weight of the polymer constituting the graft moiety is preferably 5,000 or more, more preferably 10,000 or more, and even more preferably 20,000 or more. In order to enhance the effect of imparting impact strength, the weight-average molecular weight of the polymer constituting the graft moiety is preferably 2,000,000 or less, more preferably 1,000,000 or less, and even more preferably 500,000 or less. The weight average molecular weight of the polymer constituting the graft moiety can be measured by gel permeation chromatography (GPC) using a component soluble in an organic solvent such as tetrahydrofuran (THF).

[0056] The grafted portion can be formed by graft polymerizing a monomer component containing a (meth)acrylate in the presence of a rubbery polymer. The graft polymerization can be carried out by a known method, and emulsion polymerization is preferred. For example, after obtaining a rubber polymer latex by emulsion polymerization, a monomer component containing a (meth)acrylate for forming a graft moiety is added to the rubber polymer latex and emulsion polymerization is carried out to produce polymer (A). In this case, an emulsifier and a polymerization initiator can be added as necessary.

[0057] The emulsifier used in the polymerization of the graft portion may be the same as the emulsifiers exemplified in the description of the rubber polymer, and anionic emulsifiers and nonionic emulsifiers are preferred. The polymerization initiator used for the polymerization of the graft portion may be the same as the polymerization initiators exemplified in the description of the rubber polymer, and azo-based initiators and redox-based initiators are preferred.

[0058] The polymerization temperature for the graft polymerization is not particularly limited, and can be, for example, 30 to 100°C. The polymerization time for the polymerization of the graft portion is not particularly limited, and can be, for example, 3 to 30 hours.

[0059] The number average particle size of the polymer (A) is preferably 10 nm or more, more preferably 30 nm or more, even more preferably 50 nm or more, and particularly preferably 70 nm or more, because this improves dispersibility in the thermoplastic resin. Also, the number average particle size of the polymer (A) is preferably 1000 nm or less, more preferably 800 nm or less, and even more preferably 600 nm or less, because this improves impregnation with the phosphate ester.

[0060] The number average particle size is measured, for example, by the following method. A sample prepared by diluting a latex of polymer (A) with deionized water to a concentration of approximately 3% by mass is used to measure the number-based particle size distribution using a capillary particle size distribution analyzer (Model CHDF2000 particle size distribution analyzer manufactured by MATEC Corporation, USA), and the median diameter is taken as the number-average particle size.

[0061] The solvent-insoluble content of the polymer (A) is preferably 90% by mass or more, more preferably 92% by mass or more, and even more preferably 95% by mass or more, since this will further enhance the effect of imparting impact strength. The solvent used for measuring the solvent-insoluble content is not particularly limited as long as it does not chemically alter the polymer (A) and has sufficient solubility for the non-crosslinked polymer in the polymer (A). Acetone is preferred as the solvent because it is highly volatile and can be easily removed by distillation. However, since acetone has low solubility in polymers whose main component is styrene, tetrahydrofuran (THF) is preferred when the polymer (A) contains structural units derived from styrene.

[0062] The solvent-insoluble content is measured by preparing a solution containing 1% by mass of the polymer (A) and 99% by mass of a solvent, and carrying out the following operations (1) to (4). (1) The solution is centrifuged at 20,000 rpm for 30 minutes. (2) Extract the supernatant and place it in a flask. (3) The flask containing the supernatant from (2) is placed in a thermostatic bath at 56°C, and the volatile matter is removed from the supernatant using an evaporator. (4) The residue in the flask is dried at 120°C for 3 hours to obtain a "dried sample." The mass of the dried sample (solvent-soluble content) is measured, and the solvent-insoluble content is calculated using the following formula. wais=(wc1-was) / wc1×100 wc1: mass of polymer (A) subjected to measurement was: mass of solvent soluble matter wais: mass of solvent insoluble matter In the above operation, the "free polymer" is extracted as a solvent-soluble component.

[0063] The swelling degree of the polymer (A) in toluene solvent is preferably from 3 to 50 times, more preferably from 5 to 40 times, and even more preferably from 10 to 30 times, since this will enhance the effect of imparting impact strength.

[0064] The degree of swelling of the polymer (A) in a toluene solvent is calculated by the following method. The dried polymer (A) is weighed accurately and placed in a test tube. An excess amount of toluene (approximately 100 times the mass of the dried polymer (A)) is added to the test tube, and the tube is left to stand in a thermostatic water bath at 30°C for 48 hours. The resulting toluene solution is then filtered through a 100-mesh wire screen, and the mass W1 (g) of the resulting filtrate is measured. The filtrate is then dried to completely remove the toluene, and the mass W2 (g) of the dried product is measured, and the swelling degree is calculated using the following formula (1). Swelling degree = (W1 - W2) / W2 (1)

[0065] [Phosphate ester (B)] As the phosphate ester (B), a phosphate ester that is widely used as a non-halogen liquid flame retardant can be used, and it is preferable that the viscosity at 25°C is 100 mPa s or less because it has excellent impregnation ability into the polymer (A).

[0066] The viscosity of the phosphate ester (B) at 25°C is preferably 100 mPa·s or less, more preferably 80 mPa·s or less, and even more preferably 60 mPa·s or less. When the viscosity of the phosphate ester (B) is equal to or less than the above upper limit, the impregnation ability into the polymer (A) is improved, and when the phosphate ester (B) is blended into a resin composition, the effect of suppressing bleed-out is easily obtained. The lower limit of the viscosity of the phosphate ester (B) at 25°C is not particularly limited, and may be, for example, 10 mPa·s or more. The viscosity of the phosphate ester (B) is a value measured at 25°C using a rotational viscometer in accordance with JIS Z-8803-2011.

[0067] The freezing point of the phosphate ester (B) is preferably 0°C or lower, more preferably -10°C or lower, even more preferably -20°C or lower, and particularly preferably -30°C or lower. When the freezing point of the phosphate ester (B) is equal to or lower than the upper limit, the impregnation into the polymer (A) is more excellent, and when the phosphate ester (B) is blended into a resin composition, the effect of suppressing bleed-out is more likely to be obtained. The lower limit of the freezing point of the phosphate ester (B) is not particularly limited, and may be, for example, -50°C or higher. The freezing point of the phosphate ester (B) is a value measured by differential scanning calorimetry (DSC).

[0068] (Phosphate ester (B1)) The phosphate ester (B) preferably contains a phosphate ester (B1) having a viscosity at 25° C. of 100 mPa·s or less, and more preferably consists of only the phosphate ester (B1). The viscosity of the phosphate ester (B1) at 25°C is preferably 100 mPa·s or less, more preferably 80 mPa·s or less, and even more preferably 60 mPa·s or less. The lower limit of the viscosity of the phosphate ester (B1) at 25°C is not particularly limited, and may be, for example, 10 mPa·s or more.

[0069] The freezing point of the phosphate ester (B1) is preferably 0° C. or lower, more preferably −10° C. or lower, even more preferably −20° C. or lower, and particularly preferably −30° C. or lower. There are no particular restrictions on the lower limit of the freezing point of the phosphate ester (B1), and it can be, for example, −50° C. or higher.

[0070] The phosphorus content of the phosphate ester (B1) is preferably 5% or more, more preferably 8% or more. When the phosphorus content of the phosphate ester (B1) is equal to or more than the above lower limit, the flame retardancy is excellent. The upper limit of the phosphorus content of the phosphate ester (B1) is not particularly limited and can be, for example, 30% or less, preferably 25% or less, and more preferably 15% or less. The phosphorus content of the phosphate ester (B1) is, for example, preferably 5 to 25%, more preferably 8 to 15%.

[0071] Examples of the phosphate ester (B1) include tricresyl phosphate (phosphorus content: 8.4% by mass, viscosity (25°C): 58 mPa·s, freezing point: −20°C or lower) and cresyl diphenyl phosphate (phosphorus content: 9.1% by mass, viscosity (25°C): 36 mPa·s, freezing point: −30°C). Of these, tricresyl phosphate and cresyl diphenyl phosphate are preferred because of their excellent impregnation properties into the polymer (A). The phosphate ester (B1) may be used alone or in combination of two or more kinds.

[0072] (Other phosphate esters (B2)) The viscosity of the phosphate ester (B) may be adjusted to an appropriate range by mixing the phosphate ester (B1) with a phosphate ester (B2) other than the phosphate ester (B1). As other phosphate esters (B2), phosphate esters that are widely used as non-halogen flame retardants can be used for adjusting the phosphorus content, etc.

[0073] The phosphorus content of the other phosphate ester (B2) is preferably 5 to 25%, more preferably 8 to 15%. When the phosphorus content is equal to or greater than the lower limit, the flame retardancy is excellent. The upper limit of the phosphorus content is not particularly limited, and is, for example, 30% or less.

[0074] Other examples of the phosphate ester (B2) include triphenyl phosphate (phosphorus content: 9.5% by mass, melting point: 50°C), trixylenyl phosphate (phosphorus content: 7.6% by mass, viscosity (25°C): 172 mPa·s, freezing point: -15°C), and CR-733S (manufactured by Daihachi Chemical Industry, product name: CR-733S, phosphorus content: 10.9% by mass, viscosity (40°C): 800 mPa·s, freezing point: -1 3°C), CR-741 (manufactured by Daihachi Chemical Industry, product name: CR-741, phosphorus content: 8.9% by mass, viscosity (40°C): 2380 mPa·s, freezing point: 4°C), PX-110 (manufactured by Daihachi Chemical Industry, product name: PX-110, phosphorus content: 7.8% by mass, viscosity (25°C): 1400 mPa·s), PX-200 (manufactured by Daihachi Chemical Industry, product name: PX-200, phosphorus content: 9.0% by mass, melting point: 95°C). The other phosphate esters (B2) may be used singly or in combination of two or more.

[0075] When the phosphate ester (B1) and the other phosphate ester (B2) are used in combination as the phosphate ester (B), the content of the other phosphate ester (B2) relative to 100% by mass of the phosphate ester (B) is preferably 1 to 90% by mass, more preferably 10 to 80% by mass, and more preferably 20 to 70% by mass. When the content of the other phosphate ester (B2) is equal to or greater than the lower limit, flame retardancy and hydrolysis resistance are excellent. On the other hand, when the content of the other phosphate ester (B2) is equal to or less than the upper limit, impregnation into the polymer (A) is excellent.

[0076] In the composition according to this embodiment, the phosphate ester (B) is present in a state of being impregnated in the polymer (A). The amount of phosphate ester (B) contained in polymer (A) is preferably 50 to 200 parts by mass, more preferably 75 to 150 parts by mass, and even more preferably 90 to 110 parts by mass, per 100 parts by mass of polymer (A). When the amount of phosphate ester (B) contained in polymer (A) is equal to or greater than the lower limit, the effect of improving flame retardancy when blended into a resin composition is high. When the amount of phosphate ester (B) contained in polymer (A) is equal to or less than the upper limit, it is advantageous because the thermoplastic resin is not excessively plasticized.

[0077] The method for impregnating the polymer (A) with the phosphate ester (B) is not particularly limited. For example, the phosphate ester (B) may be added dropwise to a powder of the polymer (A) and stirred. If necessary, the viscosity of the phosphate ester (B) may be adjusted by heating.

[0078] [Other ingredients] The composition according to the embodiment may contain components other than the polymer (A) and the phosphoric acid ester (B). The other components are not particularly limited, but examples thereof include compounds remaining in the production of the composition according to the embodiment and various additives.

[0079] Examples of compounds remaining in the composition include emulsifiers, polymerization initiators, chain transfer agents, catalysts, pH adjusters, coagulants, coagulation aids, residual monomer components, etc., which are present when the polymer (A) is produced by emulsion polymerization. The content of these compounds is preferably 5% by mass or less, more preferably 3% by mass or less, and even more preferably 1% by mass or less, relative to the total mass (100% by mass) of the composition, in order to improve the physical properties and appearance of the molded article.

[0080] The additives are not particularly limited and include, for example, antioxidants, powder flowability improvers, etc. When an additive is used, it is preferable to blend the additive after impregnating the polymer (A) with the phosphate ester (B). In order to maintain better physical properties and appearance of the molded body, the content of the additives is preferably 5% by mass or less, more preferably 3% by mass or less, and even more preferably 1% by mass or less, relative to the total mass (100% by mass) of the composition.

[0081] <Resin composition> The resin composition according to the embodiment includes the composition according to the embodiment and a thermoplastic resin.

[0082] As the thermoplastic resin, either a crystalline resin or an amorphous resin can be used. Examples of the crystalline resin include polyolefin, polyamide, polyester, polyacetal, polyphenylene sulfide, polyaryl ether ketone, and polytetrafluoroethylene. Examples of amorphous resins include polycarbonate, polymethyl methacrylate, polyvinyl chloride, polystyrene, polyethersulfone, polyetherimide, and polyamideimide. The thermoplastic resins may be used alone or in combination of two or more.

[0083] The composition according to the embodiment can sufficiently suppress the bleeding out of the phosphate ester (B) even when a crystalline resin is used as the thermoplastic resin, and therefore the resin composition according to the embodiment is particularly useful when the thermoplastic resin is a crystalline resin. A suitable example of the resin composition includes the composition according to the embodiment and a crystalline resin, and more preferably includes the composition according to the embodiment and a polyester.

[0084] Examples of polyesters include polyethylene terephthalate, polybutylene terephthalate, etc. One type of polyester may be used alone, or two or more types may be used in combination. As the polyester, polybutylene terephthalate is preferred because it has excellent strength, toughness, and electrical properties.

[0085] The content of the composition according to the embodiment in the resin composition is preferably 1 part by mass or more, more preferably 3 parts by mass or more, even more preferably 5 parts by mass or more, and particularly preferably 10 parts by mass or more, relative to 100 parts by mass of the thermoplastic resin. When the content of the composition according to the embodiment is equal to or more than the lower limit, excellent impact resistance and flame retardancy are exhibited. On the other hand, the content of the composition according to the embodiment in the resin composition is preferably 100 parts by mass or less, more preferably 90 parts by mass or less, even more preferably 80 parts by mass or less, and particularly preferably 70 parts by mass or less, relative to 100 parts by mass of the thermoplastic resin. When the content of the composition according to the embodiment is equal to or less than the upper limit, it is easy to suppress a decrease in the flowability and heat distortion temperature of a molded article produced using the resin composition.

[0086] The resin composition may contain other components as long as the effects of the present invention are not impaired. Examples of other components include various well-known additives. Specific examples include anti-drip agents, stabilizers, flame retardants, flame retardant auxiliaries, hydrolysis inhibitors, antistatic agents, foaming agents, dyes, pigments, etc. The resin composition may also contain the additives exemplified in the description of the composition above or compounds remaining during polymer production. The content of other components in the resin composition is, relative to the total mass (100 mass%) of the resin composition, The content is preferably 0.01 to 10% by mass.

[0087] The method for producing the resin composition is not particularly limited. For example, the resin composition can be produced by mixing the composition according to the embodiment with a thermoplastic resin by a known method. The mixing method is not particularly limited, and examples thereof include methods of mixing and kneading using a tumbler, a V-type blender, a super mixer, a Nauta mixer, a Banbury mixer, a kneading roll, an extruder, or the like.

[0088] By molding the resin composition according to the embodiment, a desired molded article can be produced. The molding method is not particularly limited, and examples thereof include injection molding, extrusion molding, blow molding, and calendar molding. The molding temperature is not particularly limited, but is typically 150 to 500°C.

[0089] The uses of the molded article obtained by molding the resin composition according to the embodiment are not particularly limited, and examples thereof include the automotive field, the office automation equipment field, home appliances, the electrical and electronic field, the construction field, the lifestyle and cosmetics field, and the medical product field. More specifically, examples include personal computer housings, mobile phone housings, personal digital assistant housings, portable game machine housings, interior and exterior components for printers, copiers, etc., conductive coating materials, automobile interior and exterior components, light reflecting plates, building exterior components, resin window frame components, flooring materials, piping components, etc.

[0090] <Action and effect> The composition of the present invention contains polymer (A), which is a graft copolymer containing a rubber polymer, and can improve impact resistance by blending it with a matrix resin. Also, the composition of the present invention contains phosphate ester (B), and can improve flame retardancy by blending it with a matrix resin. Furthermore, in the composition of the present invention, the phosphate ester (B) is present in an impregnated state in the polymer (A), which prevents the phosphate ester (B) from bleeding out when the composition is blended with a matrix resin. In particular, the polymer (A) having a graft moiety containing a (meth)acrylate-derived structural unit exhibits excellent impregnation properties for the low-viscosity phosphate ester (B) with a viscosity of 100 mPa s or less at 25°C. The resin composition of the present invention, in which the composition of the present invention is blended with a thermoplastic resin, exhibits good moldability, and molded articles obtained using the resin composition have both excellent impact resistance and flame retardancy. [Example]

[0091] The present invention will be specifically described below with reference to examples, but the present invention is not limited to the following descriptions. In the following description, "parts" and "%" mean "parts by mass" and "% by mass" unless otherwise specified.

[0092] (Production Example 1) Production of Polymer (A-1) A separable flask equipped with a condenser, thermometer, and stirrer was charged with 250 parts of deionized water and 1 part (solids equivalent) of sodium dodecylbenzenesulfonate (Kao Corporation, product name: Neopelex G-15). The atmosphere inside the separable flask was replaced with nitrogen by passing a nitrogen stream through the flask. 49 parts of n-butyl acrylate, 1 part of allyl methacrylate, and 0.2 parts of t-butyl hydroperoxide were added, and the liquid temperature was raised to 55°C. When the liquid temperature reached 55°C, an aqueous solution containing 0.001 parts of ferrous sulfate, 0.003 parts of ethylenediaminetetraacetic acid disodium salt, and 0.24 parts of sodium formaldehyde sulfoxylate dissolved in 5 parts of deionized water was added to initiate radical polymerization. The liquid temperature was then maintained at 70°C for 60 minutes.

[0093] Further, a mixed liquid of 50 parts of methyl methacrylate and 0.2 parts of t-butyl hydroperoxide was added dropwise to the separable flask, and the liquid temperature was kept at 70°C ± 2°C for 60 minutes to obtain a latex of polymer (A-1).

[0094] Next, 420 parts of a 1.8% aqueous calcium acetate solution was heated to 85°C, and 350 parts of the polymer (A-1) latex was gradually added dropwise to the aqueous solution while stirring to coagulate the polymer (A-1). The coagulated product was filtered, washed, dehydrated, and then dried to obtain a powder of polymer (A-1).

[0095] (Production Examples 2 to 6) Production of Polymers (A-2) to (A-6) Powders of polymers (A-2) to (A-6) were obtained in the same manner as in Production Example 1, except that the components were changed as shown in Table 1.

[0096] The oil impregnation ability of the powders of polymers (A-2) to (A-6) obtained in each production example was evaluated. The results are shown in Table 1.

[0097] (impregnation) 100 parts of the polymer powder obtained in each example was added to a beaker, and 50 parts of tricresyl phosphate (manufactured by Daihachi Chemical Industry Co., Ltd., product name: TCP, phosphorus content: 8.4% by mass, viscosity (25°C): 58 mPa·s, freezing point: -20°C or lower) was added dropwise as a phosphate ester. The mixture was mixed uniformly using a medicine spoon and visually evaluated according to the following criteria. Another 50 parts of phosphate ester was added dropwise and mixed, and visual evaluation was performed again. This process was repeated until the evaluation resulted in an X rating. The amount of phosphate ester (phr) per 100 parts of polymer powder when the initial evaluation resulted in a B or X rating was recorded and evaluated according to the following evaluation criteria. The impregnation was also evaluated in the same way when cresyl diphenyl phosphate (manufactured by Daihachi Chemical Industry Co., Ltd., product name: CDP, phosphorus content: 9.1 mass%, viscosity (25°C): 36 mPa·s, freezing point: −30°C) was used as the phosphate ester. <Judgment criteria> A rating: Powder properties are maintained. B rating: The powder shows a slight tendency to aggregate (block). X: The powder is strongly blocked and cannot be loosened by shaking. Or, the liquid component does not fully soak into the powder, and it clearly adheres to the container wall.

[0098] [Table 1]

[0099] The abbreviations in Table 1 have the following meanings: BA: n-butyl acrylate St: styrene AMA: Allyl methacrylate MMA: Methyl methacrylate TCP: Tricresyl phosphate (manufactured by Daihachi Chemical Industry Co., Ltd., product name: TCP) CDP: Cresyl diphenyl phosphate (manufactured by Daihachi Chemical Industry Co., Ltd., product name: CDP)

[0100] Example 1 100 parts of polymer (A-1) was added to the tank of a Super Mixer Piccolo (Kawata Corporation, SMP-2), and while stirring at 100 rpm, 100 parts by mass of tricresyl phosphate (manufactured by Daihachi Chemical Industry Co., Ltd., product name: TCP) as a phosphate ester was added dropwise over 30 to 60 seconds, followed by stirring at 300 to 500 rpm for 3 minutes to obtain composition (C-1) in which the phosphate ester was impregnated in polymer (A-1). As a crystalline resin, 70 parts of polybutylene terephthalate (PBT, manufactured by Mitsubishi Engineering Plastics Corporation, product name: Novaduran 5010R5), 30 parts of composition (C-1) (polymer (A-1): 15 parts, TCP: 15 parts), and 0.8 parts of an anti-drip agent (A-3750, manufactured by Mitsubishi Chemical Corporation, product name: Metablen A-3750) were blended, and the mixture was fed into a twin-screw extruder (manufactured by Ikegai Corporation, PCM-30, screw diameter 30 mm, L / D = 28.5) and melt-kneaded at a kneading temperature of 250 ° C. The mixture was discharged in the form of a strand, passed through a cooling bath, and then cut with a strand cutter to obtain a pellet-shaped resin composition. The resulting resin composition was dried overnight at 80°C and then fed into a 100-ton injection molding machine (manufactured by Sumitomo Heavy Industries, Ltd., product name: SE-100DU) and injection-molded at a cylinder temperature of 250°C and a mold temperature of 80°C to obtain molded articles measuring 1 / 16 inch (length 127 mm, width 12.7 mm, thickness 1.6 mm). The resulting molded articles were subjected to a combustion test and an evaluation of bleeding properties. The results are shown in Table 2.

[0101] Examples 2 to 4 Compositions (C-2) to (C-4) were obtained in the same manner as in Example 1, except that the polymers and phosphate esters used were changed as shown in Table 2. Next, pellet-shaped resin compositions were obtained in the same manner as in Example 1, except that compositions (C-2) to (C-4) were used to obtain the formulations shown in Table 2. Molded articles were then produced in the same manner as in Example 1, and a combustion test and an evaluation of bleeding properties were carried out. The results are shown in Table 2.

[0102] (Comparative Example 1) A pellet-shaped resin composition was obtained in the same manner as in Example 1, except that the phosphate ester was not impregnated into the polymer (A-1) and instead the crystalline resin, the phosphate ester and the anti-drip agent were blended. The resulting resin composition was dried overnight at 80°C, and the liquid component was clearly bleeding from the pellet surface. When this resin composition was fed into a molding machine, the resin composition could not be fed due to bridging, and a molded product could not be produced.

[0103] (Comparative Example 2) A pellet-shaped resin composition was obtained in the same manner as in Example 1, except that the crystalline resin, polymer (A-5), phosphate ester, and anti-drip agent were blended without performing the step of pre-mixing the polymer and phosphate ester using a super mixer. The resulting resin composition was dried overnight at 80°C, and the liquid component was clearly bleeding from the pellet surface. When this resin composition was fed into a molding machine, the resin composition could not be supplied due to bridging, and a molded product could not be produced.

[0104] (Comparative Example 3) A pellet-shaped resin composition was obtained in the same manner as in Example 1, except that neither the phosphate ester nor the polymer was used. The obtained resin composition was dried overnight at 80°C, and then a molded article was produced in the same manner as in Example 1. The obtained molded article was subjected to a combustion test and an evaluation of bleeding properties. The results are shown in Table 2.

[0105] (Combustion test) The molded articles produced in each example were used as test specimens and tested in accordance with the UL-94 standard (vertical test method), and the sum of the burning times (total burning time) of five test specimens in a single flame contact was measured.

[0106] (Evaluation of bleeding properties) The molded body produced in each example was used as a test specimen, and the test specimen was left to stand in an oven at 80°C for 1 hour. Immediately after removing the test specimen, the surface of the test specimen was wiped with a Kimwipe soaked in acetone, and the wipe marks were visually inspected under LED lighting and evaluated according to the following criteria. <Evaluation criteria> ○: Wiping marks cannot be recognized. ×: Wiping marks are visible.

[0107] [Table 2]

[0108] The abbreviations in Table 2 have the following meanings: TCP: Tricresyl phosphate (manufactured by Daihachi Chemical Industry Co., Ltd., product name: TCP) CDP: Cresyl diphenyl phosphate (manufactured by Daihachi Chemical Industry Co., Ltd., product name: CDP) PBT: Polybutylene terephthalate (Mitsubishi Engineering Plastics Corporation, product name: Novaduran 5010R5) A-3750: Anti-drip agent (Mitsubishi Chemical Corporation, product name: Metablen A-3750)

[0109] As shown in Table 2, the molded articles of Examples 1 to 4, which used compositions in which the phosphate ester (B) was impregnated in the polymer (A), had a longer total burning time in the combustion test and were more flame retardant than Comparative Example 3, which did not use either the polymer (A) or the phosphate ester (B).

Claims

1. A composition containing a polymer (A) and a phosphoric acid ester (B), The polymer (A) has a core portion containing a rubber polymer and a graft portion containing a structural unit derived from a (meth)acrylate, The composition, wherein the phosphate ester (B) is present in a state of being impregnated in the polymer (A).

2. The composition according to claim 1, wherein the phosphate ester (B) comprises a phosphate ester (B1) having a viscosity at 25°C of 100 mPa·s or less.

3. The composition according to claim 2, wherein the phosphate ester (B1) has a freezing point of 0°C or lower.

4. The composition according to claim 1, wherein the content of the (meth)acrylate-derived structural units in the graft portion is 65% by mass or more relative to all structural units (100% by mass) in the graft portion.

5. 2. The composition according to claim 1, wherein the rubbery polymer comprises at least one selected from the group consisting of butadiene rubber, silicone rubber, and acrylic rubber.

6. The composition according to claim 1 , wherein the graft portion further contains a structural unit derived from an aromatic vinyl monomer.

7. The composition of claim 1 which is a resin modifier.

8. A resin composition comprising the composition according to any one of claims 1 to 7 and a thermoplastic resin.

9. The resin composition according to claim 8 , wherein the thermoplastic resin is a crystalline resin.

10. The resin composition according to claim 8 , wherein the thermoplastic resin is a polyester.

11. The resin composition according to claim 10, wherein the polyester is polybutylene terephthalate.

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