TW201718663A - Organic polymer fine particles - Google Patents

Abstract

The present invention provides: organic polymer fine particles having high heat resistance; and a method for producing organic polymer fine particles, by which organic polymer fine particles having high heat resistance are able to be produced by suspension polymerization at reduced cost.

Description

Organic polymer microparticles

This invention relates to organic polymer microparticles.

Conventionally, in order to improve the physical properties such as the anti-adhesive property and the smoothness of the resin molded article, or to further impart properties, there has been proposed a resin composition in which the base resin contains organic or inorganic fine particles. Since the fine particles are often used in combination with the base resin, if the heat resistance of the fine particles is poor, the fine particles are decomposed by heating during the forming process, causing problems such as poor appearance of the molded article (pore, coloring, etc.) or deterioration of mechanical properties. Therefore, it is desired to have fine particles excellent in heat resistance.

The organic polymer fine particles described in Patent Document 1 are obtained by polymerizing a monomer component containing a (meth)acrylic monomer, and the sulfur-based antioxidant is an antioxidant contained in a thioether-based compound, and contains 10 ppm or more (mass basis), an average particle diameter of 0.5 μm to 40 μm, and an initial thermal cracking temperature of 290 ° C or more. When the suspension polymerization is carried out in the aqueous phase, it is known to add a water-soluble polymerization terminator such as sodium nitrite to the system in order to suppress the generation of by-produced fine particles by the emulsion polymerization (see Patent Document 2).

The organic polymer microparticles are produced by seed polymerization or suspension polymerization. In the case of seed polymerization, although particles having a relatively uniform particle size are easily obtained, the production cost is easily improved. In the case of suspension polymerization, although the production cost can be suppressed, fine particles are likely to be generated. Patent Document 3 describes a spherical gap agent produced by seed polymerization. In the examples, a spherical interstitial agent having a particle diameter CV value (coefficient of variation) of 10% or less was obtained, and 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl group was used in the reaction.

In the production of the organic polymer fine particles, it is preferred to use the suspension polymerization to produce organic polymerized fine particles having excellent heat resistance from the viewpoint of low production cost.

[Advanced technical literature] [Patent Literature]

Patent Document 1: International Publication No. 2008/133147

Patent Document 2: Japanese Patent Laid-Open No. Hei 7-316209

Patent Document 3: Japanese Patent Laid-Open No. 2015-72364

Therefore, an object of the present invention is to provide an organic polymer fine particle having high heat resistance and a method for producing an organic polymer fine particle capable of producing cost-effective and high heat-resistant organic polymer fine particles by suspension polymerization.

The present inventors have found that when organic polymer microparticles are produced by suspension polymerization, organic polymer microparticles having high heat resistance can be obtained by suppressing the generation of fine particles. Further, it has been found that by containing a specific compound during suspension polymerization, generation of fine particles can be suppressed, and highly heat-resistant organic polymer fine particles can be produced.

In other words, the organic polymer fine particles of the present invention contain a polymer derived from a constituent unit of a vinyl monomer and a nitroxide radical compound, and have a CV value (variation coefficient) of a particle diameter of 15% or more.

The above nitroxide radical compound is preferably 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl.

The vinyl monomer preferably contains a styrene monomer.

Further, the vinyl monomer preferably contains a maleimide-based monomer.

Further, the vinyl monomer preferably contains a (meth)acrylic monomer. The vinyl monomer preferably contains at least two of the above styrene monomer, maleimide monomer, and (meth)acrylic monomer.

The present invention contains an additive for a thermoplastic resin containing the above organic polymer fine particles, and a release agent for a thermoplastic resin containing the above organic polymer fine particles. Further, the above-described additive containing a thermoplastic resin and a masterbatch of a thermoplastic resin are preferred embodiments of the present invention.

In the method for producing an organic polymer microparticle of the present invention, a vinyl monomer is suspension-polymerized in the presence of a nitroxide radical compound.

The above nitroxide radical compound is preferably 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl.

The vinyl monomer preferably contains a styrene monomer.

Further, the vinyl monomer preferably contains a maleimide-based monomer.

Further, the vinyl monomer preferably contains a (meth)acrylic monomer. The vinyl monomer preferably contains at least two of the above styrene monomer, maleimide monomer, and (meth)acrylic monomer.

The present invention is to add a specific compound during suspension polymerization. Organic polymer microparticles with few fine particles and high heat resistance can be provided. Further, by adding a specific compound during suspension polymerization, it is possible to provide a method for producing an organic polymer fine particle capable of producing a cost-effective and high heat-resistant organic polymer fine particle.

Figure 1 is a scanning electron micrograph of the surface of the biaxially stretched film of Example 1.

Fig. 2 is a TG (Thermo gravity) curve measured by keeping the fine particles and the suspended particles at 280 ° C (the highest reaching temperature) for 2 hours.

Fig. 3 is a TG (Thermo gravity) graph measured under the conditions of holding the organic polymer fine particles of Example 1 and Comparative Example 1 at 230 ° C (maximum reaching temperature) for 2 hours.

Organic polymer microparticles

The organic polymer fine particles of the present invention contain a polymer containing a constituent unit derived from a vinyl monomer and a nitronium radical compound, and the CV value (variation coefficient) of the particle diameter is 15% or more.

1-1 polymer

The polymer contained in the organic polymer fine particles of the present invention contains a constituent unit derived from a vinyl monomer. A polymer containing a constituent unit derived from a vinyl monomer can be obtained by polymerizing a vinyl monomer.

1-1-1 vinyl monomer

The vinyl monomer may specifically be, for example, a (meth)acrylic monomer, a styrene monomer or a maleimide monomer. In addition, in this case, "(A The "acrylic monomer" means an acrylic monomer, a methacrylic monomer, and a mixture thereof, and "(meth)acrylic" means acrylic acid, methacrylic acid, and the like.

The vinyl monomer preferably contains any one of the above styrene monomer, maleimide monomer, and (meth)acrylic monomer, and more preferably contains the above styrene. Any two or more of a monomer, a maleimide-based monomer, and a (meth)acrylic monomer.

1-1-1-1 (meth)acrylic monomer

The (meth)acrylic single system may contain (A) a monofunctional (meth)acrylate monomer, (B) a polyfunctional (meth)acrylate monomer, and (meth) Acrylonitrile and the like.

In the present specification, "(A) monofunctional (meth) acrylate monomer" means a monomer having only one (meth) acryl fluorenyl group in the molecule. (A) a monofunctional (meth) acrylate system, in addition to the above (meth) fluorenyl group, may have a radical polymerizable group other than a vinyl group in other monomers. In addition, when a carboxyl group, a hydroxyl group, an alkoxy group, an isomeric cyanate group, or the like is a group to be reacted (bonded), a condensable reactive group such as an ester bond can be formed. Such a condensable reactive group also functions as a "polymerizable group".

The monofunctional (meth) acrylate system of the above (A) may, for example, be (meth)acrylic acid; methyl (meth)acrylate, ethyl (meth)acrylate or propyl (meth)acrylate. , n-butyl (meth) acrylate, isobutyl (meth) acrylate, amyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, (meth) acrylate Octyl ester, decyl (meth) acrylate, decyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, 2-ethyl (meth) acrylate (meth) acrylate alkyl esters such as hexyl hexyl ester; cyclopropyl (meth) acrylate, cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, cyclooctyl (meth) acrylate , (cyclo)alkyl (meth)acrylate, cyclododecyl (meth)acrylate, isobutyl (meth)acrylate, 4-tert-butylcyclohexyl (meth)acrylate, etc. ( Methyl) acrylate cycloalkyl esters; 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, etc. (methyl Hydroxyalkyl acrylates; phenyl (meth) acrylate, benzyl (meth) acrylate, toluene (meth) acrylate, phenethyl (meth) acrylate, etc. Ester; allyl (meth) acrylate such as allyl (meth) acrylate. These (A) monofunctional (meth) acrylate type single system may be used alone or in combination of two or more. Among these, a (meth) acrylate alkyl ester is preferable, and a methyl (meth) acrylate is more preferable.

The content of the (A) monofunctional (meth) acrylate monomer is preferably from 0 to 40 parts by mass, more preferably from 0 to 30 parts by mass, per 100 parts by mass of the vinyl monomer.

The above (B) polyfunctional (meth) acrylate monomer refers to a monomer having 2 or more (meth) acryl fluorenyl groups in the molecule. The (B) polyfunctional (meth) acrylate system alone is similar to the above (A) monofunctional (meth) acrylate monomer, and may be used in addition to the (meth) acrylonitrile group. When a radical polymerizable group such as a vinyl group is present in other monomers, for example, a carboxyl group, a hydroxyl group, an alkoxy group, an isomeric cyanate group or the like may become a base of a reaction (bonding) object. At the time, a condensable reactive group such as an ester bond can be formed.

Examples of the (B) polyfunctional (meth) acrylate system include ethylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, and 1,6. - hexanediol di(meth) acrylate, 1,9-nonanediol di(meth) acrylate, Alkanediol di(meth)acrylate such as 1,10-nonanediol di(meth)acrylate, di(meth)acrylic acid-1,3-butane diester; diethylene glycol di(methyl) Acrylate, triethylene glycol di(meth)acrylate, decaethylene glycol di(meth)acrylate, pentaethylene glycol di(meth)acrylate, one hundred and fifty ethylene glycol di(a) Polyalkylene glycol di(meth) acrylate, polyethylene glycol di(meth) acrylate, polypropylene glycol di(meth) acrylate, polybutylene glycol di(meth) acrylate Di(meth)acrylates such as acrylates; tris(meth)acrylates such as trimethylolpropane tri(meth)acrylate; tetrakis(methyl) such as pentaerythritol tetra(meth)acrylate Acrylates; hexa(meth)acrylates such as dipentaerythritol hexa(meth)acrylate; tris(propylene oxyethyl) cyanide, isomeric cyanurate Polyethyl amide), alkylene oxide addition of tris(propylene oxyethyloxy), and alkylene oxide addition of tris (methacryloxyethyl) (meth)acrylonitrile-based iso-cyanates; A polyfunctional allyl-containing isocyanurate such as triallyl cyanurate or the like. These (B) polyfunctional (meth) acrylate type single system may be used alone or in combination of two or more. Among these, it is preferable to have 2 or more (meth) acrylonitrile groups in one molecule, and more preferably 3 or more (meth) acryl fluorenyl groups in one molecule. Further, among the (B) polyfunctional (meth)acrylate monomers, alkanediol di(meth)acrylates and tris(meth)acrylates are preferred, and ethylene glycol II is more preferred. (Meth) acrylate, trimethylolpropane tri(meth) acrylate.

1-1-1-2 styrene monomer

The styrene-based single system may, for example, be styrene; an alkyl styrene such as o-methyl styrene, m-methyl styrene, p-methyl styrene, α-methyl styrene or p-tert-butyl styrene; An aromatic ring-containing styrene such as p-phenylstyrene; a halogen-containing styrene such as styrene, m-chlorostyrene or p-chlorostyrene; a hydroxy group-containing styrene such as p-hydroxystyrene; an alkoxystyrene such as p-methoxystyrene; and the like. These styrene-based single systems may be used singly or in combination of two or more. Among these, styrene is preferred.

The content of the styrene-based monomer is preferably from 1 to 95 parts by mass, more preferably from 30 to 90 parts by mass, particularly preferably from 50 to 70 parts by mass, per 100 parts by mass of the vinyl monomer. When the content of the styrene-based monomer is at least 1 part by mass, the heat resistance of the organic polymer fine particles can be further improved, and the aromatic polyester resin tends to have higher affinity and dispersibility. When the content of the styrene monomer exceeds 95 parts by mass, the crosslinkability is liable to lower.

1-1-1-3 maleic acid imide monomer

In the organic polymer fine particles of the present invention, the vinyl monomer preferably contains a maleimide-based monomer. By containing a maleimide-based monomer, the initial thermal cracking temperature of the organic polymer microparticles in a non-oxidizing environment can be further improved. The maleimide-based monosystem can be, for example, represented by the general formula (I):

[In the formula (I), R ¹¹ and R ¹² each independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 15 carbon atoms, an aryl group having 1 to 15 carbon atoms, or an aralkyl having 1 to 15 carbon atoms. The group R ¹³ represents an alkyl group having 1 to 15 carbon atoms, an aryl group having 1 to 15 carbon atoms, or an aralkyl group having 1 to 15 carbon atoms. ]

The alkyl group represented by R ¹¹ to R ¹³ may, for example, be a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a decyl group, a decyl group, an undecyl group or a tetradecyl group. a linear alkyl group such as an alkyl group, a tridecyl group, a tetradecyl group or a pentadecyl group; a branched alkyl group such as an isopropyl group, an isobutyl group or a tributyl group; a cyclopropyl group and a cyclobutyl group; a cyclic alkyl group such as a cyclopentyl group or a cyclohexyl group. Examples of the aryl group represented by R ¹¹ to R ¹³ include a phenyl group and a naphthyl group. Further, the hydrogen atom of the alkyl group or the aryl group may be further substituted with an alkyl group, an aryl group, a halogen atom, a nitro group or the like. Examples of the aralkyl group represented by R ¹¹ to R ¹³ include a benzyl group, a phenethyl group, and a 3-phenylpropyl group.

Specific examples of the above-mentioned maleimide-based monomer include, for example, maleimide, N-methylbutyleneimine, and N-ethylbutylene Amine, N-propyl maleimide, N-butyl maleimide, N-cyclohexyl maleimide, N-lauryl maleimide, etc. N- Alkyl maleimide; N-phenyl maleimide, N-(2-chlorophenyl) maleimide, N-(3-chlorophenyl) cis Acetylimine, N-(4-chlorophenyl)maleimide, N-(4-bromophenyl)maleimide, N-(2,4,6-three Chlorophenyl) maleimide, N-(2,4,6-tribromo)maleimide, N-(2-nitrophenyl)butyleneimine, N-(3-nitrophenyl) maleimide, N-(4-nitrophenyl) maleimide, N-(2,4-dinitrophenyl) cis Butyleneimine, N-(2-hydroxyphenyl) maleimide, N-(3-hydroxyphenyl) maleimide, N-(4-hydroxyphenyl) N-aryl maleimide, such as maleimide, N-(4-phenylphenyl) maleimide, N-naphthyl maleimide; N-(2- Phenyl phenyl) maleimide, N-(3-methylphenyl) maleimide, N-(4-methylphenyl) maleimide, N- (2-butylphenyl) maleimide, N-(3-butylphenyl) maleimide, N-(4-butylphenyl)butylene Amine, N-(2,6-dimethylphenyl)butylene N-alkylaryl maleimide, such as amine; N-(2-methoxyphenyl) maleimide, N-(3-methoxyphenyl)butylene Imine, N-(4-methoxyphenyl) maleimide, N-(4-ethoxyphenyl) maleimide, N-(2-methoxy- 4-Alkylphenyl) alkoxyaryl-butyleneimine such as maleimide; aryloxyaryl group such as N-(4-phenoxyphenyl) maleimide An arylalkyl maleimide such as maleimide or a benzyl maleimide or the like. These maleimide-based mono-systems may be used singly or in combination of two or more. Among these, N-alkyl maleimide (preferably N-cyclic alkyl maleimide) and N-aryl maleimide are preferred. More preferably, it is N-cyclohexylmethyleneimine, N-phenyl maleimide.

The content of the maleimide-based monomer is preferably from 0 to 40 parts by mass, more preferably from 0 to 25 parts by mass, particularly preferably from 1 to 25, based on 100 parts by mass of the vinyl monomer. Parts by mass. When the content of the above-mentioned maleimide-based monomer is 1 part by mass or more, the initial thermal cracking temperature-increasing effect by the maleimide-based monomer can be sufficiently obtained, if it is 30 parts by mass. Hereinafter, the colorlessness (whiteness) of the organic polymer fine particles is enhanced.

1-1-1-4 crosslinker

The vinyl monomer of the organic polymer fine particles of the present invention may contain a crosslinking agent as a constituent component. Among the above (meth)acrylic monomers, those having two or more polymerizable groups can be used as a crosslinking agent. Other examples include aromatic divinyl compounds such as divinylbenzene, divinylnaphthalene, and the like; N,N-divinylaniline, diethylene sulfide, divinylsulfonic acid; divinyl ether, B. Glycol divinyl ether, diethylene glycol divinyl ether, polyethylene glycol divinyl ether, propylene glycol divinyl ether, butyl glycol divinyl ether, hexanediol divinyl ether, bisphenol A alkylene oxide Divinyl ether, bisphenol F alkylene oxide divinyl ether, trimethylolpropane trivinyl ether, bis(trimethylolpropane) tetravinyl ether, glycerol trivinyl ether, pentaerythritol tetravinyl ether, dipentaerythritol pentavinyl ether , dipentaerythritol hexene enol ether, ethylene oxide addition trimethylolpropane trivinyl ether, ethylene oxide addition bis(trimethylolpropane) tetravinyl ether, ethylene oxide addition pentaerythritol tetravinyl ether Polyfunctional vinyl ethers such as ether and ethylene oxide addition dipentaerythritol hexenene ether; ethylene glycol diallyl ether, diethylene glycol diallyl ether, polyethylene glycol diallyl ether, propylene glycol Allyl ether, butyl glycol diallyl ether, hexanediol diallyl ether, bisphenol A alkylene oxide diallyl ether, bisphenol F alkylene oxide diallyl ether, trimethylolpropane three Allyl ether, bis(trimethylolpropane)tetraallyl ether, glycerol allyl ether, pentaerythritol tetraallyl ether, dipentaerythritol pentamethicone, dipentaerythritol hexene propylene ether, ethylene oxide addition three Hydroxymethylpropane triallyl ether, ethylene oxide addition bis(trimethylolpropane) tetraallyl ether, ethylene oxide addition pentaerythritol tetraallyl ether Ethylene oxide adduct of dipentaerythritol hexa polyfunctional allyl ether, allyl ether group and the like. These crosslinking agents may be used alone or in combination of two or more. Further, in the (meth)acrylic monomer, a crosslinking agent can be used, and the (B) polyfunctional (meth)acrylate monomer is preferably used.

The content of the crosslinking agent is preferably from 0.1 to 50 parts by mass, more preferably from 1 to 30 parts by mass, particularly preferably from 5 to 15 parts by mass, per 100 parts by mass of the vinyl monomer. When the content of the crosslinking agent is 50 parts by mass or less, the particles are more excellent in the temperature at which the mass starts to decrease and the initial thermal decomposition temperature. When the content is 50 parts by mass or less, the double bond which is derived from the crosslinking agent and which tends to remain in the polymerization reaction at the time of production is not easily left. Therefore, it is judged that the decomposition starting from the remaining double bond can be suppressed. In addition, when the content is 0.1 part by mass or more, the resin composition can be suppressed or the resin composition can be processed. The organic polymer microparticles are deformed by heating during melting or processing.

1-1-1-5 other monomers

The (meth)acrylic monomer, the styrene monomer, and the maleimide monomer may be used in the organic polymer microparticles of the present invention to the extent that the effects of the present invention are not impaired. And other different monomers other than the above-mentioned crosslinking agent are constituent components. When the other monomer is used, the amount used is preferably 20 parts by mass or less, more preferably 10 parts by mass or less, based on 100 parts by mass of the total vinyl monomer.

1-2 nitroxide free radical compound

The organic polymer microparticles of the present invention contain a nitroxide radical compound. The organic polymer fine particles of the present invention improve heat resistance by containing the above-mentioned niobium radical compound. The above nitroxide radical compound can be exemplified by, for example, 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl, 2,2,6,6-tetramethylpiperidine-1- Oxyl, 4-benzylideneoxy-2,2,6,6-tetramethylpiperidin-1-yloxy, 5,5-dimethyl-1-pyrroline N-oxide, etc., can be used One or two or more of the above. Among the above nitroxide radical compounds, 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-yloxy (4H-TEMPO) represented by the following formula (II) is preferred.

The content of the nitroxide radical compound is preferably from 10 to 1,000 ppm, more preferably from 50 to 700 ppm, and particularly preferably from 70 to 500 ppm, based on the total mass of the vinyl monomer component. If the above-mentioned niobium radical compound When the content is less than 10 ppm, sufficient heat resistance is not easily obtained, and if it exceeds 1000 ppm, the polymerization property may be insufficient.

1-3 particle size

The average particle diameter (volume average particle diameter) of the organic polymer fine particles of the present invention is preferably 0.1 to 100 μm, more preferably 0.3 to 50 μm, and particularly preferably 0.5 to 30 μm. When the average particle diameter is less than 0.1 μm, the anti-adhesive effect and the smoothness-improving effect cannot be sufficiently exhibited, so that a large amount of addition is required, which may impair the mechanical strength of the film. On the other hand, when the average particle diameter is more than 100 μm, the particles are likely to fall off from the film, and there is a possibility that the mechanical strength is lowered. In addition, the "average particle diameter" in this specification means the "volume average particle diameter."

1-4 particle size CV value (coefficient of variation)

The particle diameter CV value (variation coefficient) of the organic polymer fine particles of the present invention is 15% or more, preferably 15 to 70%, more preferably 20 to 65%, and particularly preferably 25 to 60%. If the CV value is less than 15%, when suspension polymerization is carried out to obtain particles, a classification step is required, resulting in an increase in manufacturing cost. Further, when the CV value is too large, the amount of coarse particles increases, and the particles are liable to fall off from the film, which tends to cause a decrease in mechanical strength, which is not preferable.

The CV value (coefficient of variation) of the particle size can be calculated according to the following formula: CV value (%) of the particle diameter = 100 × (standard deviation of particle diameter / volume average particle diameter)

Further, the standard deviation of the particle diameter is a value obtained by using a volume-based particle size distribution.

Since the organic polymer microparticles of the present invention are produced by suspension polymerization, the CV value (variation coefficient) of the particle diameter is 15% or more.

1-5 antioxidant

The organic polymer microparticles of the present invention may also contain an antioxidant. By containing an antioxidant, heat resistance can be further improved. Examples of the antioxidant include a hindered phenol antioxidant, a sulfur antioxidant, a phosphorus antioxidant, a lactone antioxidant, a hydroxylamine antioxidant, and a vitamin E antioxidant. Further, the hindered phenol-based antioxidant means that the structure of the antioxidant has a para-substituted 2,6-di-t-butylphenol structure; the sulfur-based antioxidant means a sulfur-containing element and has an antioxidant function; The antioxidant means that the structure contains a phosphorus atom; and the lactone type antioxidant means a cyclic ester structure. These structures may contain two or more types at the same time. In this case, in the present specification, each of the antioxidants is mainly classified in accordance with a portion exhibiting an antioxidant effect.

It is known that a sulfur-based antioxidant can have an aromatic ring, for example, thiodiethylidene bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 4, 6-bis(dodecylthiomethyl) o-cresol, 4,6-bis(octylthiomethyl)o-cresol, 2,6-di-t-butyl-4-(4,6-double (octylthio)-1,3,5-tri-2-ylamino)phenol, etc.; for those without an aromatic ring, for example, pentaerythritol tetrakis(3-laurylthiopropionate), 3, 3 '-Di(dodecyl ester) thiodipropionate, di(octadecyl ester) 3,3'-thiodipropionate, dimyristyl 3,3-thiopropionate, 3, 3-Thienyl dipropionate ditridecyl ester and the like. Among these, a thioether-based compound (having a C-SC bond) is preferred, and a pentaerythritol tetrakis(3-laurylthiopropionate) is more preferred. Since these sulfur-based antioxidants can be obtained at low cost, they are preferred.

Further, the compound (1) having a structural unit represented by the following formula (1) is also a sulfur-based antioxidant which is preferably used in the present invention.

[Chemical 3]

Further, in the formula (1), n represents an integer of 1 to 5 (preferably n = 2).

In the compound (1), a compound having two or more structural units represented by the above formula (1) in the molecule is preferred. More preferably, it is a compound having 2 to 4 structural units represented by the above formula (1) in the molecule, and more preferably a compound having four structural units represented by the above formula (1) in the molecule.

Further, among the above compounds (1), the compound (2) having a structural unit represented by the following formula (2) is preferred. The compound (2) is more preferably a compound having 2 to 4 structural units represented by the following formula (2) in the molecule, and more preferably a compound having 4 structural units represented by the following formula (2).

Wherein n is an integer of 1 to 5 (preferably n=2); and R ¹ is at least one selected from the group consisting of an alkyl group, an aryl group, an aralkyl group, and an alkenyl group, and R ¹ may have Substituent.

The alkyl group is preferably an alkyl group having 1 to 20 carbon atoms, more preferably 3 to 20 carbon atoms, and particularly preferably an alkyl group having 6 to 18 carbon atoms, from the viewpoint of high heat resistance enhancement effect. For example: propyl, butyl, pentyl, hexyl, octyl, dodecyl (lauryl), tridecyl, myristyl, octadecyl (stearyl) alkyl groups.

Examples of the aryl group include a phenyl group, a hydroxyphenyl group, a tolyl group, and an orthoquinone group. Base. Among these, a phenyl group and a hydroxyphenyl group are preferable.

Examples of the aralkyl group include a benzyl group, a methylbenzyl group, a phenethyl group, a methylphenethyl group, a phenylbenzyl group, and a naphthylmethyl group; and the alkenyl group may, for example, be a vinyl group or an allyl group. Propylene group, 1-butenyl group, 2-butenyl group and the like.

Among these, an alkyl group or an aryl group is preferred, and an alkyl group is more preferred.

The above substituents may, for example, be a hydroxyl group, an amine group, a carboxyl group, an alkyl group, an aryl group, an aralkyl group or an alkenyl group.

The compound (2) having four structural units represented by the above formula (2) is preferably, for example, a pentaerythritol tetrakis(3-alkylthiopropionate) compound. Specifically, for example, pentaerythritol tetrakis(3-methylthiopropionate), pentaerythritol tetrakis(3-ethylthiopropionate), pentaerythritol tetrakis(3-propylthiopropionate), pentaerythritol IV can be exemplified. (3-butylthiopropionate), pentaerythritol tetrakis(3-hexylthiopropionate), pentaerythritol tetrakis(3-octylthiopropionate), pentaerythritol tetrakis(3-laurylthiopropionate) , pentaerythritol tetrakis(3-tridecylthiopropionate), pentaerythritol tetrakis(3-myristylthiopropionate), pentaerythritol tetrakis(3-stearylthiopropionate), pentaerythritol IV (3-phenylthiopropionate) and the like. Among them, those having a carbon number of 3 to 20, more preferably an alkyl group having 6 to 18 carbon atoms, and a particularly preferred alkyl group having 12 to 18 carbon atoms are preferred.

In particular, pentaerythritol tetrakis(3-laurylthiopropionate) having an alkyl group having 12 carbon atoms is preferred because it is industrially easy to obtain.

Further, among the compounds (1), the compound (3) having a structural unit represented by the following formula (3) may be a sulfur-based antioxidant which is preferably used in the present invention.

In the formula (3), n is an integer of 1 to 5 (preferably n = 2).

Among the compounds (3) having a structural unit represented by the above formula (3), a compound having a structural unit represented by the following formula (4) is more preferred.

n is an integer from 1 to 5 (preferably n=2).

In the formula (4), R ² and R ³ are each independently selected, and at least one selected from the group consisting of an alkyl group, an aryl group, an aralkyl group and an alkenyl group; and R ² and R ³ may also be used. Has a substituent. Further, the alkyl group, the aryl group, the aralkyl group, and the alkenyl group are preferably the same as those in the case of R ^{1 of the} above compound (2). Further, R ² and R ^{3 are} preferably an alkyl group or an aryl group, more preferably an alkyl group.

The above substituents may, for example, be an alkyl group, an aryl group, an arylalkyl group, an alkenyl group, a hydroxyl group, an amine group or a carboxyl group.

The compound (3) having a structural unit represented by the formula (4) is preferably, for example, a 3,3'-thiodipropionate dialkyl ester compound. Specifically, for example, dimethyl 3,3′-thiodipropionate, diethyl 3,3′-thiodipropionate, dipropyl 3,3′-thiodipropionate, 3, 3'-dibutyl thiodipropionate, dihexyl 3,3'-thiodipropionate, dioctyl 3,3'-thiodipropionate, 3,3'-thiodipropionic acid Di(dodecyl ester) (dilaurate 3,3'-thiodipropionate), 3,3'-thiodipropionate dimyristyl ester, 3,3'-thiodipropionic acid (Tridecyl ester), 3,3'-thiobispropionate di(octadecyl ester) (3,3'-thiodipropionate distearyl ester) and the like. Among these, those having an alkyl group having 3 to 20 carbon atoms, more preferably a compound having an alkyl group having 6 to 18 carbon atoms, more preferably a compound having an alkyl group having 12 to 18 carbon atoms are preferable.

In particular, 3,3'-thiodipropionic acid having an alkyl group having 12 to 18 carbon atoms Di(dodecyl ester), 3,3'-thiodipropionate dimyristate, 3,3'-thiodipropionate di(tridecyl), 3,3'-thio Dioctadecyl dipropionate is preferred because it is relatively easy to obtain industrially.

The above-mentioned hindered phenol-based antioxidant can be specifically exemplified by pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 3-(3,5-di-third-butadiene). Octadecyl-1-hydroxyphenyl)propionate, N,N'-hexane-1,6-diylbis[3-(3,5-di-t-butyl-4-hydroxyphenyl) Acetamide, phenylpropionic acid, 3,5-bis(1,1-dimethylethyl)-4-hydroxy, C7-C9 side chain alkyl ester, 3,3',3",5, 5',5"-hexa-t-butyl-a, a', a"-(mesitylene-2,4,6-tolyl)tris-cresol, diethylbis[[[3,5- Bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]phosphonic acid] calcium, ethyl bis(oxyethyl) bis[3-(5-tert-butyl-4) -hydroxy-m-tolyl)propionate], hexamethylenebis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 1,3,5-tri ( 3,5-di-t-butyl-4-hydroxybenzyl)-1,3,5-tri-2,4,6(1H,3H,5H)-trione, 1,3,5-tri[( 4-tert-butyl-3-hydroxy-2,6-fluorenyl)methyl]-1,3,5-tri-2,4,6(1H,3H,5H)-trione, N-phenyl Reaction product of aniline with 2,4,4-trimethylbenzene, diethyl[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]phosphonic acid Ester, 2,4-dimethyl-6-(1-methylpentadecyl)phenol, octadecyl-3-(3,5-third -4-hydroxyphenyl) propionate, 2 ', 3-bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propan-acyl] propan-acyl hydrazine.

The phosphorus-based antioxidant may, for example, be tris(2,4-di-t-butylphenyl phosphate) or tris[2-[[2,4,8,10-tetra-tert-butyldibenzo[d] , f][1,3,2]diphosphoheptan-6-yl]oxy]ethyl]amine, bis(2,4-di-t-butylphenyl)pentaerythritol diphosphate, phosphorous Bis[2,4-bis(1,1-dimethylethyl)-6-methylphenyl]ethyl ester, tetrakis(2,4-di-t-butylphenyl)[1,1-biphenyl Base]-4,4'-diylbisphosphonate, and the like.

The lactone-based antioxidant may, for example, be a reaction product of 3-hydroxy-5,7-di-t-butylfuran-2-one and o-xylene (CAS No. 181314-48-7).

Further, for example, a hydroxylamine-based antioxidant such as an oxidation product of an alkylamine ester using the reduced tallow as a raw material; 3,4-dihydro-2,5,7,8-tetramethyl- Vitamin E antioxidants such as 2-(4,8,12-trimethyltridecyl)-2H-benzopyran-6-ol and the like.

Among the above-mentioned antioxidants, at least one selected from the group consisting of hindered phenol-based antioxidants, sulfur-based antioxidants, phosphorus-based antioxidants, and lactone-based antioxidants is preferably used. The particularly hindered phenol-based antioxidant is preferably pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], and the phosphorus-based antioxidant is preferably tris(2,4-phosphate). The di-tert-butylphenyl ester), the lactone-based antioxidant is preferably a reaction product of 3-hydroxy-5,7-di-t-butylfuran-2-one and o-xylene.

The antioxidant is preferably contained in the organic polymer fine particles of the present invention in an amount of about 10 ppm or more, preferably 15 ppm or more, more preferably 50 ppm or more. If the content of the antioxidant is too small, it may be difficult to obtain a heat resistance improving effect. The upper limit is not particularly limited, but is preferably 5% or less, more preferably 3% or less.

2. Method for producing organic polymer microparticles

In the method for producing the organic polymer fine particles of the present invention, the vinyl monomer is subjected to suspension polymerization in the presence of a nitroxide radical compound. In the method for producing the organic polymer microparticles of the present invention, by carrying out the reaction in the presence of a nitronium radical compound, emulsion polymerization which is a side reaction can be suppressed, and generation of fine particles can be suppressed. Therefore, organic polymer fine particles excellent in heat resistance can be obtained in a good yield.

The vinyl system is set to be in a preferred form with the above monomers. with. Further, in addition to the monomer composition, additives such as pigments, plasticizers, polymerization stabilizers, fluorescent whitening agents, magnetic powders, ultraviolet absorbers, antistatic agents, and flame retardants may be added; Starter, dispersion stabilizer, antioxidant, etc. Further, the polymerization reaction is preferably carried out in a solvent. In this case, the monomer composition may be placed in a solvent in a predetermined preparation, or each component, an additive or the like may be separately introduced into a solvent and mixed in a solvent.

Examples of the polymerization solvent include alcohols such as alcohol; alcohols such as methanol, ethanol, and isopropyl alcohol; ketones such as acetone and methyl ethyl ketone; aromatic hydrocarbons such as toluene and xylene; and esters such as ethyl acetate. The polymerization solvent is preferably water.

The "suspension polymerization" is generally carried out by dispersing and suspending a monomer composition containing a monomer component and an additive in a polymerization solvent, and then polymerizing the droplet suspension composition thus obtained to obtain a polymerization solvent. A method of dispersing a dispersion containing organic polymer microparticles. In the preparation of the droplet suspension composition, a means for suspending the monomer composition in the polymerization solvent may be a conventionally known dispersion and suspension method and apparatus. For example, a high-speed mixer such as a T.K. homomixer or a line mixer (for example, Ebara Milder (registered trademark)) can be used.

The suspension polymerization of the present invention is carried out in the presence of a nitroxide radical compound. The nitroxide radical compound may be contained at the beginning of the polymerization reaction, and it is preferred to add the niobium radical compound before the polymerization of the droplet suspension composition. The nitroxide radical compound can be set to be the same as the above preferred embodiment.

The amount of the nitroxide radical compound to be added is preferably 0.05 parts by mass to 0.5 parts by mass, more preferably 0.08 parts by mass to 0.3 parts by mass, based on 100 parts by mass of the total of the vinyl monomer component. Addition amount of nitroxide radical compound When the amount is less than 0.05 parts by mass, the suppression of the generation of fine particles is likely to be insufficient, and when the amount of addition is more than 0.5 parts by mass, the polymerization reaction may be suppressed.

In order to control the droplet size 俾 of the monomer composition to stabilize, it is preferable to coexist the dispersion stabilizer described later in the preparation of the droplet suspension composition. Here, the polymerization initiator (described later) may be present in the suspension composition at the time of the polymerization reaction, and is preferably dispersed and dissolved in the monomer composition when the droplet suspension composition is prepared. In the phase or the polymerization solvent phase, it is particularly preferable to preliminarily dissolve the form in the monomer composition. The polymerization is preferably carried out under stirring. The agitation may be agitation of a known agitating blade such as a blade, a turbine blade, a Burmagin blade, or a propeller blade.

Therefore, the suspension polymerization is preferably constituted by the following steps: (1) a step of preparing a monomer composition by dispersing and dissolving a polymerization initiator, an antioxidant in a monomer component; (2) being dispersed, a step of preparing a droplet suspension composition by suspending the above monomer composition in a solvent in which a dispersion stabilizer (optionally used) is dissolved; (3) adding a nitronium radical compound immediately before the start of the polymerization reaction (4) starting the polymerization reaction of the droplet suspension composition (using heating or the like) to polymerize the droplet-shaped monomer composition, thereby preparing a dispersion composed of the polymer microparticles dispersed in a solvent. The step of the liquid.

The above-mentioned substance can be used for the antioxidant. In the production method of the present invention, the monomer component is subjected to radical polymerization in the presence of an antioxidant, and therefore the antioxidant is preferably dissolved in the monomer component or the polymerization solvent. The blending amount of the antioxidant is preferably set to 0.01 (100 ppm) to 5 mass based on the total amount of the monomer components. %. More preferably, it is 0.05 (500 ppm) to 3% by mass, and particularly preferably 0.1 to 1% by mass. Further, it is preferable to set the range of the above-mentioned blending amount regardless of whether the antioxidant is a sulfur-based antioxidant alone or a combination of a sulfur-based antioxidant and another antioxidant.

In the polymerization reaction, a polymerization initiator may be used, or a method of starting polymerization by using radiation irradiation or applying heat may be employed. As the polymerization initiator, any one which is usually used in radical polymerization can be used, and for example, a peroxide-based initiator, an azo-based initiator, or the like can be used. The peroxide-based initiator may, for example, be benzamidine peroxide, lauric acid peroxide, octyl peroxide, ortho-benzyl benzoyl peroxide, ortho-methoxybenzophenone. Examples of the azo initiator include dimethyl 2,2'-azobisisobutyrate, 2,2'-azobisisobutyronitrile, and 2,2'-azobis (2,4). - dimethyl valeronitrile), 2,2'-azobis(2,3-dimethylbutyronitrile), and the like. The polymerization initiator is preferably used in an amount of from 0.01 part by mass to 20 parts by mass per 100 parts by mass of the vinyl monomer component (more preferably from 0.1 part by mass to 10 parts by mass).

Further, in the polymerization reaction, a dispersion stabilizer (emulsifier) may be used in order to stably carry out the polymerization reaction. As the above dispersion stabilizer, for example, a water-soluble polymer such as polyvinyl alcohol, gelatin, sodium polyacrylate or polymethyl methacrylate; sodium lauryl sulfate or polyoxyethylidene phenyl ether sulfate salt can be used (for example) Anionic surfactants such as polyoxyethylene distyryl phenyl ether sulfate ammonium; cationic surfactants such as alkylamine salts and quaternary ammonium salts; and zwitterionic interfaces such as lauryl dimethylamine oxide Active agent; nonionic surfactant such as polyoxyethylene ethyl ether; others such as: alginate, zein, casein, barium sulfate, calcium sulfate, barium carbonate, magnesium carbonate, phosphoric acid Calcium, talc, clay, diatomaceous earth, bentonite, titanium hydroxide, barium hydroxide, metal oxygen Compound powder, etc.

The above-mentioned dispersion stabilizer may be appropriately adjusted in the amount of the organic polymer fine particles to be used. For example, in the case of obtaining an organic polymer fine particle having an average particle diameter of 1 μm to 20 μm, it is preferably 0.01 parts by mass to 10 parts by mass based on 100 parts by mass of the vinyl monomer component (more preferably 0.05 parts by mass to 5 parts by mass, more preferably 1 part by mass to 2 parts by mass).

The polymerization temperature is preferably 60 ° C ~ 100 ° C (more preferably 65 ° C ~ 95 ° C, particularly good 70 ° C ~ 90 ° C); polymerization is preferably 2 hours ~ 7 hours (more preferably 2.5 hours ~ 5 hours, Very good for 3 hours to 4.5 hours). Further, the polymerization reaction is preferably carried out in the range of pH 4 to pH 10.

Further, the organic polymer fine particles obtained by the polymerization reaction are subjected to solid-liquid separation by dispersing the dispersion liquid contained in the polymerization solvent to obtain organic polymer fine particles. The solid-liquid separation method can be, for example, filtration, centrifugation, or the like.

Further, a coagulant can also be used in the solid-liquid separation. Examples of the coagulant include metal salts such as sodium chloride, magnesium chloride, calcium chloride, sodium sulfate, aluminum sulfate, zinc sulfate, magnesium sulfate, sodium hydrogencarbonate, sodium carbonate, ammonium chloride, and potassium alum; sulfuric acid and hydrochloric acid; Acids such as phosphoric acid, nitric acid, carbonic acid, acetic acid, alcohols such as methanol and ethanol, and the like. These coagulants may be used singly or in combination of two or more.

The amount of the aggregating agent to be added is not particularly limited, and is 0.05 parts by mass to 10 parts by mass based on 100 parts by mass of the organic polymer fine particles in the dispersion. The time required for coagulation is short, usually causing agglomeration within a range of 0.1 minutes to 2 hours. Therefore, it is not preferable to add the coagulant in a hurry, and it is not preferable, and the coagulant is preferably added to the dispersion slowly. Further, the temperature of the dispersion liquid when the coagulant is added is preferably from 30 ° C to 100 ° C.

3. Use

The organic polymer fine particles of the present invention have fewer fine particles than conventional particles, and have a small weight reduction rate at 230 to 280 ° C and excellent heat resistance. Therefore, when the organic polymer fine particles of the present invention are melt-mixed in a non-oxidizing environment such as a nitrogen atmosphere, the decomposition product is less likely to be generated, and resin coloring and residual bubbles are less likely to occur, so that it is suitable as a resin additive. The resin to which the organic polymer microparticles of the present invention are added may be, for example, a thermoplastic resin, and preferably, for example, a polyester resin, a polyolefin resin, a polyamide resin, a polyurethane resin, a (meth)acrylic resin, or a polycarbonate resin. , polystyrene resin, etc. Among these, if the melting point is high, it is necessary to melt and mix the additive of the polyester resin which is applied at a relatively high temperature, and the effect of the present invention can be further exerted by using the organic polymer fine particles of the present invention.

In the additive for a resin, the organic polymer fine particles of the present invention are excellent in heat resistance, can suppress coloring (excellent in color fastness), and can control the refractive index of the organic polymer fine particles in a wide range according to the composition, so that it can be effectively used as a resin. Anti-adhesive agent, light diffusing agent. When the organic polymer fine particles of the present invention are used as an additive for a resin, the organic polymer fine particles may be used singly or in combination with other components.

4. Masterbatch

As described above, the organic polymer fine particles of the present invention can be effectively used as an additive for a resin. Moreover, since the organic polymer fine particles of the present invention are excellent in heat resistance, the melt processing temperature can be increased, and mixing can be performed with lower melt viscosity. Therefore, even if the blending amount of the organic polymer microparticles to the resin is increased, the organic polymer microparticles can be easily dispersed uniformly. Therefore, a masterbatch containing the organic polymer microparticles of the present invention and a resin is also preferred.

The resin used for the master batch is preferably a thermoplastic resin, and more preferably, for example, a polyester resin, a polyolefin resin, a polyamide resin, a polyurethane resin, a (meth)acrylic resin, a polycarbonate resin, or a polyphenylene. Vinyl resin, etc. Among these, if the melting point is high, it is necessary to melt and mix the additive of the polyester resin which is applied at a relatively high temperature, and the effect of the present invention can be further exerted by using the organic polymer fine particles of the present invention. Therefore, the additive for polyester containing the fine particles of the organic polymer of the present invention and the masterbatch of the polyester resin are preferred in the present invention.

The polyester resin is not particularly limited, and is preferably, for example, polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, or polycyclohexylene dimethylene. An aromatic polyester resin such as phthalic acid ester, polyethylene 2,6-naphthalenedicarboxylate or polybutyl 2,6-naphthalene dicarboxylate. These systems may be used alone or in combination of two or more. Among these, a polyethylene terephthalate resin is preferred.

The content of the organic polymer fine particles in the master batch is not particularly limited, and is preferably 0.1 part by mass or more, more preferably 1 part by mass or more, and particularly preferably 5 parts by mass or more based on 100 parts by mass of the resin in the master batch. It is preferably 400 parts by mass or less, more preferably 200 parts by mass or less, more preferably 100 parts by mass or less, and most preferably 80 parts by mass or less.

The method for preparing a masterbatch containing the fine particles of the organic polymer of the present invention may be a method of adding a mixed organic polymer fine particle in a polymerization stage of a synthetic resin, and a method of performing melt mixing using an extruder or the like for the polymerized resin. A method of mixing organic polymer fine particles or the like in a state where the resin is dissolved in a solvent. Among these, the method of melt mixing can clearly exert the effect of using the organic polymer microparticles of the present invention, and it is easy to produce a high concentration dispersion containing organic The resin composition of the polymer microparticles is quite suitable for the production of a masterbatch.

The method of mixing in the polymerization stage of the synthetic resin may, for example, be added to a polyester resin such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN), in the case of When a diol component such as an alcohol is polymerized with a dicarboxylic acid (ester) component, the organic polymer fine particles are dispersed in one component (preferably a diol component), and the polymerization reaction is carried out in the presence of the organic polymer microparticles. .

The method of melt-kneading may be, for example, a method in which a powder or a granular polyester resin is mixed with an organic polymer fine particle (a form dispersed in a powder or a solvent), and the polyester resin is melted while being stirred to perform a mixing treatment; A method of mixing organic polymer fine particles (a form dispersed in a powder or a solvent) in a state where the polyester resin is melted.

The masterbatch prepared is usually processed into a powder or granules. Then, the master batch was added to the same resin as the resin contained in the master batch, and melt-mixing was carried out to prepare a resin composition. By using the organic polymer fine particles of the present invention as an additive, a resin composition capable of suppressing coloration and generation of bubbles can be obtained.

5. Resin composition

A resin composition containing the organic polymer microparticles of the present invention and a resin is also preferred. When the organic polymer fine particles of the present invention are melt-mixed in a non-oxidizing environment such as a nitrogen atmosphere, a decomposition product is less likely to be generated, and thus a resin composition capable of suppressing coloration, residual bubbles, and the like can be obtained.

Further, in the organic polymer fine particles of the present invention, even when the resin composition is subjected to heat molding, the decomposition product is less likely to be generated, and thus a resin molded body which suppresses coloration, residual bubbles, and the like can be obtained. Also, because of the dispersion of the resin Preferably, a resin molded body (for example, a film or the like) having a low haze can be obtained.

The resin composition may be prepared by mixing the above master batch with a resin, or may be directly prepared by mixing the organic polymer microparticles of the present invention with a resin.

The method of forming the resin composition into a film or the like is, for example, hot molding such as injection molding or extrusion molding; the resin composition is diluted with a solvent, and the liquid resin composition is applied onto a support serving as a substrate. Method, etc.

The method of mixing the polyester resin additive with the polyester resin is not particularly limited, and may be added at the polymerization stage of the polyester resin, or may be melt-mixed using an extruder or the like on the polymerized polyester resin. .

[Examples]

Hereinafter, the present invention will be described in more detail by way of examples, but the invention is not limited thereto. In addition, the "parts" described in the following examples represent "parts by mass", and "%" means "mass%".

<Evaluation method>

(1) Volume average particle size

The particle size distribution measuring apparatus ("Coulter Multisizer III type" Beckman Coulter) was used to measure the particle diameter of 30,000 particles, and the volume average particle diameter and the standard deviation of the particle diameter were determined from the volume-based particle size distribution, and according to the following formula The CV value (coefficient of variation) of the particle diameter was calculated.

CV value (%) of particle size = 100 × (standard deviation of particle diameter / volume average particle diameter)

(2) Thermal decomposition evaluation

The thermal decomposition evaluation of the obtained organic polymer microparticles was carried out using a thermal analysis device ("Miscellaneous thermal scale Thermo plus EV02/TG-DTA" Rigaku shares have The company's product was measured under the conditions of a sample amount of 10 mg, a nitrogen atmosphere, a flow rate of 200 ml/min, a temperature increase rate of 10 ° C/min, and 230 ° C or 280 ° C (maximum arrival temperature) for 2 hours. Then, the heat resistance of the organic polymer fine particles was evaluated from the obtained TG (Thermo gravity) curve.

(3) Compound quantification

The quantification of the related 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl radical was carried out using a gas chromatography layer analyzer (6890N (trade name), manufactured by Agilent Technologies, capillary column). DB-1 (trade name); length 30 m × inner diameter 0.25 mm, film thickness 0.25 μm) was measured. The 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl radical contained in 0.2 parts of the obtained organic polymer fine particles was extracted by using 1 part of acetone as an extraction medium. Then use the previously prepared calibration curve to obtain.

(4) The number of tiny particles attached to the surface of the suspended particles

Using a scanning electron microscope (SEM) ("JCM-6000 NeoScope", manufactured by JEOL Ltd.), the organic polymer microparticles were observed at a magnification of 5000 times, and the number of fine particles attached to the surface of the suspended particles was calculated according to the following method. . The fine particles have a diameter of 50 to 300 nm, and the suspended particles have a diameter of 1 μm or more.

Ten suspended particles were observed, and the number of fine particles attached to the surface of each suspended particle was counted, and the average number of fine particles attached to one suspended particle was calculated.

(5) Determination of the amount of fine particles in the filtrate (solid content of the filtrate)

The polymerization liquid which has completed the polymerization reaction was filtered using a filter paper (Quantitative filter paper "No. 5C" manufactured by Advantec Toyo Co., Ltd.) to separate fine particles (filtrate) from suspended particles (residue). 2 g of the filtrate containing fine particles was placed in an aluminum cup, and dried by heating on a hot plate heated to 110 ° C for 1 hour to evaporate water in the filtrate to obtain fine particles. Using the weight before and after drying, according to the following formula The amount (%) of the fine particles (solid content of the filtrate) contained in the filtrate was calculated.

The solid content of the filtrate (%) = [weight (g) of the fine particles obtained after the filtrate is dried] / [filtrate weight (g)] × 100

[Example 1]

Filled in a beaker: 40 parts of N-(phenyl) maleimide (PMI), 100 parts of styrene (St), 40 parts of methyl methacrylate (MMA), trimethylolpropane 20 parts of trimethacrylate (TMPTMA), 1 part of lauryl peroxide (LPO), hindered phenol-based antioxidant (manufactured by Ciba Specialty Chemicals Co., Ltd., trade name "Irganox (registered trademark) 1010", and pentaerythritol IV [3-(3,5-Di-t-butyl-4-hydroxyphenyl)propionate]) 1 part, the solid component was dissolved in a 35 ° C warm bath. In a flask equipped with a stirrer, an inert gas introduction tube, a reflux cooler, and a thermometer, a dissolved polyoxyethylene distyrylphenyl ether sulfate ammonium salt (trade name "HITENOL (registered trademark) NF-08") is charged. (1), 2 parts of deionized water, 2 parts of deionized water, a solution of a beaker was added, and a uniform suspension was formed by stirring at 8000 rpm for 5 minutes using a TK homogenizer (manufactured by Special Machine Chemical Co., Ltd.). 0.2 parts of 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl radical (4H-TEMPO, "POLYSTOP 7010" manufactured by Bodo Co., Ltd.) and 500 parts of deionized water were added.

Next, while blowing nitrogen gas into the flask, the temperature was raised to 65 ° C, and the reaction vessel was kept at 65 °C. When the liquid temperature reached 74 ° C by the self-heating effect, the reaction was started. After stirring at this temperature for 1 hour, the polymerization liquid was further heated to 85 ° C and stirred for 1.5 hours to complete the polymerization reaction. Then, under stirring, 0.6 parts of dissolved aluminum sulfate was added to deionized water at 85 ° C. After stirring at this temperature for 1.5 hours, the reaction liquid was cooled, and the polymerization product was subjected to hot air drying at 80 ° C for 12 hours to obtain organic polymer fine particles.

The obtained organic polymer fine particle system had an average particle diameter of 2.77 μm and a CV value (coefficient of variation) of 40.1%. Further, the obtained organic polymer fine particle system contained 660 ppm of 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl radical (4H-TEMPO). In Table 1, the total of the monomer component and the crosslinking agent is 100 parts by mass, and the ratio of use of each component is described. Further, the evaluation results of the obtained organic polymer fine particles are shown in Table 1. In addition, in Table 1, the particle diameter is a volume average particle diameter. The water content of the organic polymer microparticles is 1% or less.

In addition, the obtained organic polymer fine particles were agglomerated by drying, and thus were crushed at a normal temperature by a crushing pressure of 0.4 MPa using a super jet mill SJ-500 (manufactured by Nissin Engineering Co., Ltd.). Thereby, organic polymer microparticles which are not agglomerated are formed.

Masterbatch production

10 parts of the obtained organic polymer fine particles, 90 parts of polyethylene terephthalate particles (manufactured by SA-8339 PUnitika Co., Ltd.), Irganox (registered trademark) 1010: 0.15 parts of antioxidant, and Irgafos (registered trademark) 168: 0.15 parts, mixed by a co-rotating biaxial kneading extruder (manufactured by HK-25D PARKER CORPORATION), melt-kneaded at 250 ° C, and water-cooled to obtain strands. The obtained strands were appropriately cut to obtain a polyethylene terephthalate masterbatch which was doped with 10% of the organic polymer fine particles.

Cast film production

Using the obtained polyethylene terephthalate masterbatch and polyethylene terephthalate Diester particles were prepared into two three-layer cast films. The structure in which the skin layer of the organic polymer microparticles is added is laminated on both sides of the core layer. In the production of the cast film, extrusion molding was carried out at 280 ° C using a T-die extrusion molding machine (manufactured by Chuangyan Co., Ltd.). The skin layer of the double-layered organic polymer microparticles is 10 parts of the master batch of organic polymer microparticles, 1 part of the polyethylene terephthalate particles, and the core layer is only polyethylene terephthalate. The ester granules were 180 parts. The thickness of the cast film was set to 16 μm in the skin layer to which the organic polymer fine particles were added, and the core layer was set to 288 μm to obtain a cast film having a total thickness of 320 μm.

Production of biaxially stretched film

The obtained cast film was cut into a length × width = 9 cm × 9 cm, and a synchronous biaxial stretching machine (manufactured by Toyo Seiki Co., Ltd.) was used, and the stretching ratio was set to 3 times in the vertical direction and 3 times in the horizontal direction. Biaxially stretched to obtain a biaxially stretched film. The size of the obtained biaxially stretched film was 22 cm x 22 cm. Further, the central portion of the biaxially stretched film system has an average thickness of 10 μm, the film end portion is about 40 μm, and the main film portion of the central portion of 12 cm × 12 cm to 18 cm × 18 cm is about 10 μm thick.

The surface of the central portion of the obtained biaxially stretched film was observed by a scanning electron microscope (SEM) ("JCM-6000 NeoScope", manufactured by JEOL Ltd.) in a 500-fold field of view. It was confirmed that organic polymer fine particles were present on the surface of the biaxially stretched film. The SEM photograph of the surface of the biaxially stretched film is shown in Fig. 1. In addition, the haze of the center portion of the obtained biaxially stretched film was measured by a measuring instrument (NDH 7000, Nippon Denshoku Industries Co., Ltd.) and found to be 0.96.

[Comparative Example 1]

Except 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl free radicals The organic polymer fine particles were produced in the same manner as in Example 1 except for (4H-TEMPO). The evaluation results of the obtained organic polymer fine particles are shown in Table 1.

As shown in Table 1, the organic polymer microparticles of Example 1 containing 4H-TEMPO: 660 ppm were produced using 4H-TEMPO, and observed by scanning electron microscopy, the average particle size of the fine particles was 9 and the filtrate was solid. The share is also 0.93% less. On the other hand, in the case where 4H-TEMPO was not used, the organic polymer fine particles of Comparative Example 1 which did not contain 4H-TEMPO were observed by a scanning electron microscope, and as a result, an average of 114 fine particles were observed. In the state, the solid content of the filtrate was also in a state of 4.91%.

Figure 2 shows the respective thermal decomposition evaluation of suspended particles (residues) and fine particles (solids of the filtrate) in the organic polymer microparticles, in a nitrogen environment, The TG (Thermo gravity) curve measured at 280 ° C (maximum arrival temperature) for 2 hours. The horizontal axis system starts the measurement to be 0 point.

As shown in Fig. 2, it was found that the weight loss rate of the suspended particles from the time of reaching 280 ° C for 120 minutes was less than 3.54 wt%, and the fine particles were in a state of 8.80 wt%.

3 is a thermal decomposition evaluation of the organic polymer microparticles of Example 1 and Comparative Example 1, and a TG (Thermo gravity) curve measured under a nitrogen atmosphere at 230 ° C (maximum reaching temperature) for 2 hours. Table 1 shows the weight reduction rate after a given time. The horizontal axis of Fig. 3 is set to 0 for the start measurement. When the obtained organic polymer fine particles are used as an additive for a thermoplastic resin, if it is decomposed in a relatively low temperature region such as 230 ° C, adverse effects such as opaqueness of the resin and cracking may occur due to bubble generation. Therefore, under the analysis conditions of 230 ° C, the weight reduction rate is low, which is an excellent additive for resins.

As shown in FIG. 3 and Table 1, the weight loss rate of the organic polymer fine particles of Comparative Example 1 after 120 minutes from the time of reaching 230 ° C was 2.20% by weight (Δwt% is 0.44% by weight). In contrast, the organic polymer fine particles of Example 1 exhibited a low heat resistance by a low value of 1.45 wt% (Δwt%, 0.13 wt%) after 120 minutes from reaching 230 ° C.

Accordingly, the organic polymer fine particles containing 4H-TEMPO, having few fine particles and having a small solid content of the filtrate can obtain excellent heat resistance. From the above, it has been found that the heat resistance of the organic polymer fine particles can be improved by suppressing generation of fine particles in the organic polymer fine particles.

[Examples 2 to 11]

In addition to monomer composition, antioxidants, polymerization terminators, 4H-TEMPO and The types of the initiators and the amounts used were changed as shown in Table 2, and the organic polymer fine particles were obtained in the same manner as in Example 1. Table 2 shows the results of thermal decomposition evaluation of the obtained organic polymer fine particles, the number of fine particles (average), the filtration solid content, the average particle diameter, and the CV value. In addition, in Table 2, the particle diameter is a volume average particle diameter.

Further, each of the obtained organic polymer microparticles contained 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl radical (4H-TEMPO) in an amount of 10 ppm or more as in Example 1. .

[Embodiment 12]

In addition to the monomer composition, the crosslinking agent, the antioxidant, and the type of the initiator, the amount of use was changed as shown in Table 2, and 5% by mass of isopropyl ether was added to the monomer, and the TK homogenizer was used at 10,000 rpm. The organic polymer fine particles were obtained in the same manner as in Example 1 except that the mixture was stirred for 13 minutes. Table 2 shows the results of thermal decomposition evaluation of the obtained organic polymer fine particles, the number of fine particles (average), the filtration solid content, the average particle diameter, and the CV value.

Further, each of the obtained organic polymer microparticles contained 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl radical (4H-TEMPO) in an amount of 10 ppm or more as in Example 1. .

[Comparative Example 2~5]

Organic polymer microparticles were obtained in the same manner as in Example 1 except that 4H-TEMPO was not used and the monomer composition was changed to the use ratio shown in Table 3. Comparative Example 2 was substituted for 4H-TEMPO and sodium nitrite was used instead. The evaluation results of the obtained organic polymer microparticles are shown in Table 3. In addition, in Table 3, the particle diameter is a volume average particle diameter.

In Tables 2 and 3, the crosslinking agent DVB570 is DVB570 (manufactured by New Nikko Chemical Co., Ltd., the content of divinylbenzene is 55 to 60% by mass, and the content of ethylvinylbenzene is 35 to 40% by mass); the antioxidant AO-412S, PEP-36 is a sulfur-based antioxidant (manufactured by ADEKA CORPORATION, trade name "ADKSTAB (registered trademark) AO-412S", and trade name "ADKSTAB (registered trademark) PEP-36".

Further, for reference, the organic polymer microparticles of the examples and the comparative examples were kept at 280 ° C (the highest temperature reached) for 2 hours in a nitrogen atmosphere, and the weight reduction rate after a predetermined time was as shown in Table 2. Table 3. In addition, in Table 3, the *1 type resin-like polymer was more than fine particles, and it was not possible to isolate the particles, and it was not evaluated. *2 is unable to obtain data.

[Table 2]

As shown in Table 2 and Table 3, the organic polymer fine particles of the examples produced using 4H-TEMPO were observed by using a scanning electron microscope, and as a result, the number of fine particles was small and the solid content of the filtrate was also small. By using 4H-TEMPO, the yield of suspension polymerization can be increased.

On the other hand, the organic polymer fine particles of the comparative example produced without using 4H-TEMPO were observed by a scanning electron microscope, and it was observed that there were many fine particles, and the solid content of the filtrate was also large. The same applies to Comparative Example 2 in which 4H-TEMPO was replaced with sodium nitrite.

[Industrial availability]

The organic polymer microparticles of the present invention have higher heat resistance than conventional particles. Therefore, the organic polymer fine particles of the present invention are suitably used as additives for resins such as an anti-adhesive agent and a light diffusing agent.

Claims (11)

An organic polymer fine particle containing a polymer derived from a constituent unit of a vinyl monomer and a nitronium radical compound, and having a CV value (coefficient of variation) of a particle diameter of 15% or more. The organic polymer microparticles of claim 1, wherein the nitroxide radical compound is 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl. The organic polymer fine particles according to claim 1 or 2, wherein the vinyl single system contains a styrene monomer. The organic polymer fine particles according to any one of claims 1 to 3, wherein the vinyl single system contains a maleimide-based monomer. An additive for a thermoplastic resin, comprising the organic polymer microparticles according to any one of claims 1 to 4. An anti-adhesive for a thermoplastic resin, comprising the organic polymer microparticles according to any one of claims 1 to 4. A masterbatch comprising: an additive for a thermoplastic resin according to item 5 of the patent application, and a thermoplastic resin. A method for producing an organic polymer microparticle, which comprises subjecting a vinyl monomer to suspension polymerization in the presence of a nitroxide radical compound. The method for producing an organic polymer microparticle according to the eighth aspect of the invention, wherein the nitroxide radical compound is 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl. The method for producing an organic polymer fine particle according to claim 8 or 9, wherein the vinyl single system contains a styrene monomer. The method for producing an organic polymer fine particle according to any one of claims 8 to 10, wherein the vinyl-based single system contains a maleimide-based monomer.