JP5227587B2 - Ultrafine metal particle-containing resin composition and method for producing the composition - Google Patents

Description

  The present invention relates to a resin composition containing ultrafine metal particles. More specifically, the present invention relates to a metal ultrafine particle-containing resin composition obtained by mixing and heating a metal complex having an organic group and a vinyl polymer having a mercapto group at the end, and a method for producing the composition.

  Metal ultrafine particles having a particle diameter of less than 100 nm have characteristics not found in metal particles having a particle diameter of 100 nm or more, and can be used in various applications. For example, gold ultrafine particles have a characteristic of absorbing light having a wavelength of 512 nm (surface plasmon phenomenon). Therefore, the gold ultrafine particle dispersion exhibits a red color which is a complementary color of 512 nm, and the resin or paste containing the gold ultrafine particles can be used as an optical material or a paint. In addition, the ultrafine metal particles of several tens of nm have a low melting point and melt at less than 200 ° C., so that they are applied as a low-temperature fired conductive paste for printed circuit boards of electronic materials.

  As a general method for producing ultrafine metal particles, a gas phase method, a liquid phase method, and a synthesis method by thermal decomposition of a complex are known. The gas phase method is a method in which a metal as a raw material is heated and vaporized in a high vacuum to collect ultrafine metal particles (Patent Document 1).

  However, in order to vaporize the metal, it is necessary to use an expensive apparatus such as plasma, laser, or electron beam. There is also a problem that only a small amount of ultrafine metal particles can be obtained. The liquid phase method is a method in which a metal complex dissolved in a solvent is reduced with a reducing agent to obtain metal ultrafine particles, which is more suitable for mass production than a gas phase method and can produce metal ultrafine particles at a low cost (Non-patent Document 1). .

  However, since the obtained ultrafine metal particles have strong aggregation between the ultrafine particles and low compatibility with the resin, it is difficult to uniformly disperse them in the resin. The method by thermal decomposition of a complex is a method in which a metal complex having a low decomposition temperature is thermally decomposed to synthesize metal ultrafine particles simply (Patent Document 2).

  However, even when trying to combine the synthesized ultrafine metal particles and the resin, a resin composition in which the ultrafine metal particles are uniformly dispersed cannot be obtained due to the difference in polarity and viscosity between the modifier and the resin. It was. In addition, it is conceivable to treat the metal ultrafine particles synthesized by the above method with an organic treatment agent to increase the compatibility with the resin and melt knead the resin. In addition, a resin composition in which ultrafine metal particles are separated and uniformly dispersed cannot be obtained.

As a method for producing a resin composition in which ultrafine metal particles are dispersed, a method of polymerizing a resin from the surface of ultrafine metal particles (Non-Patent Documents 2 and 3), a method of synthesizing ultrafine metal particles in the presence of a resin, etc. 4). However, these methods have problems such as being unsuitable for mass production due to complicated production methods.
JP 60-78635 A Japanese Patent Laid-Open No. 10-183207 K. Matsumoto et al. , "J. Soc. Powder Technol. Jpn.", 2003, Vol. 41, No. 7, p. 489 T.A. K. Mandal et al. , “Nano Lett.”, 2003, Vol. 2, p. S. Hirano et al. , “J. Eur. Ceram. Soc.”, 2001, Vol. 21, p. 1479. S. Ogawa et al. , “Jpn. J. Appl. Phys.”, 1994, Vol. 33, L331.

  A composition in which ultrafine metal particles are uniformly dispersed in a resin without aggregation is useful, but at present, such a resin composition has not been obtained industrially. An object of the present invention is to provide a resin composition containing ultrafine metal particles that can be easily produced in large quantities.

  As a result of intensive studies, the present inventors have completed the present invention.

  That is, the present invention provides an ultrafine metal particle-containing resin composition characterized by heating a mixture of a metal complex having an organic group and a vinyl polymer having a mercapto group at the end to a thermal decomposition temperature of the metal complex or higher. Related to things.

In a preferred embodiment, the metal atom of the metal complex having an organic group is at least one element selected from the group consisting of transition metal elements, Group 3B and Group 4B metal elements, lanthanoids, and actinoids. Ultrafine metal particle-containing resin composition, wherein the metal complex having an organic group is at least one compound selected from the group consisting of organic acid metal salts, organic metal compounds, and metal alkoxides A resin composition containing a metal ultrafine particle, wherein the vinyl polymer having a mercapto group-terminated vinyl polymer is a polymer synthesized by a reversible addition / desorption chain transfer polymerization method,
A resin composition containing ultrafine metal particles, wherein the resin composition is thermoplastic;
A resin composition containing ultrafine metal particles, wherein the heating temperature is a temperature not less than the decomposition start temperature of the metal complex having an organic group and less than the complete decomposition temperature,
The number average particle diameter of the ultrafine metal particles is in the range of 0.1 nm to 100 nm, the ultrafine metal particle-containing resin composition,
A resin composition containing ultrafine metal particles, characterized by thermally decomposing a metal complex having an organic group in the presence of an organic solvent;
Examples thereof include a resin composition containing ultrafine metal particles, which further contains a thermoplastic resin.

  In the present invention, after mixing a metal complex having an organic group and a vinyl polymer having a mercapto group at its terminal, the mixture is heated to a temperature higher than the thermal decomposition temperature of the metal complex to produce ultrafine metal particles. The present invention relates to a method for producing a resin composition containing ultrafine metal particles.

  In the present invention, since ultrafine metal particles are produced in the presence of a vinyl polymer having a mercapto group at the end, a resin composition in which ultrafine metal particles are uniformly dispersed can be easily produced in large quantities. Moreover, by adjusting the compatibility between the polymer having a mercapto group at the terminal and the thermoplastic resin, a resin composition containing ultrafine metal particles having a controlled morphology can be obtained. Furthermore, the particle diameter of the ultrafine metal particles can be controlled by adjusting the molecular weight and the amount of the vinyl polymer having a mercapto group at the terminal. Since the ultrafine metal particles are produced not by the reduction method but by the thermal decomposition method, the applicable range is wide.

  The metal ultrafine particle-containing resin composition of the present invention is obtained by mixing and heating a metal complex having an organic group and a vinyl polymer having a mercapto group at the terminal, and generating metal ultrafine particles by thermal decomposition of the metal complex. It is obtained.

  The metal complex having an organic group used in the present invention is a complex composed of a metal atom and an organic group, and may contain other elements. The metal component may be a metal element excluding alkali metals and alkaline earth metals. Among these metal elements, transition metal elements, Group 3B to Group 4B metal elements, lanthanoids, and actinoids are preferable because complexes containing these metal elements have the property of generating ultrafine metal particles upon heating.

  Among them, Cu, Ag, Au, Zn, In, Si, Ge, Sn, Pd, Fe, Co, Ni, Ru, Rh, Ir, Pt, Mn, and Zr are the characteristics and availability of the ultrafine metal particles obtained. This is more preferable. Although it does not specifically limit as a complex which has an organic group used by this invention, An organic acid metal salt, a metal alkoxide, or an organometallic compound is preferable at the point of availability.

  The organic acid metal salt is a salt of an organic acid and a metal ion and is not particularly limited. For example, an aliphatic carboxylic acid metal salt, an alicyclic carboxylic acid metal salt, an aromatic carboxylic acid metal salt, an aliphatic sulfonic acid metal salt. And alicyclic sulfonic acid metal salts, aromatic sulfonic acid metal salts, aliphatic phosphonic acid metal salts, alicyclic phosphonic acid metal salts, and aromatic phosphonic acid metal salts. Among these, the above-mentioned metal acetates, laurates, oleates, stearates, and acetyl acetates are preferable from the viewpoint of availability.

  Although it does not specifically limit as a metal alkoxide, The methoxide of the said metal, ethoxide, n-propoxide, isopropoxide, n-butoxide, t-butoxide, and phenoxide are preferable at the point of availability. In the present invention, the organometallic compound refers to a compound in which a bond between a metal atom and a carbon atom or a phosphorus atom exists, and is not particularly limited, and examples thereof include an alkylated metal compound, an arylated metal compound, and a phosphinated metal compound. be able to.

  Among such organometallic compounds, methyl metal compounds, ethyl metal compounds, isopropyl metal compounds, n-butyl metal compounds, t-butyl metal compounds, cyclopentadienyl metal compounds, phenyl metal compounds, indenyls are available. Metal compounds, cyclooctadienyl metal compounds, triphenylphosphino metal compounds, tributylphosphino metal compounds, and triethylphosphino metal compounds are preferred.

  The metal complex having an organic group used in the present invention may be used alone or in combination. In the case of using a combination of a plurality, it is possible to use metal ultrafine particles as an alloy. In the present invention, since the metal complex having an organic group is thermally decomposed by heating, the decomposition temperature needs to be equal to or lower than the decomposition temperature of the vinyl-based polymer having a mercapto group. The decomposition temperature is preferably in the range of 100 ° C to 250 ° C.

  The amount of the metal complex having an organic group used in the present invention is desirably 0.1 to 300 parts by weight with respect to 100 parts by weight of the vinyl polymer having a mercapto group at the terminal. More preferably, it is 1-150 weight part. If the amount of the metal complex is less than 0.1 parts by weight, the physical properties of the ultrafine metal particles cannot be expressed. On the other hand, when the amount of the metal complex exceeds 300 parts by weight, the amount of the metal complex is too large and the heat-generated metal particles become coarse.

  The ultrafine metal particles contained in the resin composition of the present invention are synthesized in the presence of a vinyl polymer having a mercapto group at the end. The presence of a vinyl polymer having a mercapto group at the end can prevent the ultrafine metal particles from aggregating and fusing together during the production of the ultrafine metal particles, so the particle size is small and uniformly controlled. It is possible to easily synthesize metal ultrafine particles. Further, by modifying the surface of the ultrafine metal particles with a vinyl polymer having a mercapto group, the compatibility with the resin is improved, so that a composition in which the ultrafine metal particles are uniformly dispersed in the resin composition can be obtained. .

  The vinyl polymer having a mercapto group at the terminal used in the present invention is not particularly limited, and a compound having a structure having a mercapto group at the terminal and ten or more monomer units connected can be used. The polymer structure is not limited to a straight chain, a branch, a dendrimer, a hyperbranch and the like, but a linear polymer is preferable in terms of high efficiency for modifying the nanoparticles. In addition, the primary structure of the polymer is not particularly limited, and any of a homopolymer, a block polymer, a random polymer, a gradient polymer, and the like can be used, such as a syndiotactic polymer, an isotactic polymer, a heterotactic polymer, etc. Stereoregular polymers can also be used.

  Specific examples of such a polymer include polymers obtained by polymerizing vinyl acetate in the presence of thioacetic acid and then hydrolyzing the end groups. Am. Chem. Soc. , 2001, Vol. 123, page 10411, and polystyrene having a mercapto group.

  The vinyl-based polymer having a mercapto group at the terminal used in the present invention can introduce a mercapto group easily and reliably, and can control the molecular weight and molecular weight distribution, so that reversible addition-elimination chain transfer (RAFT) is possible. Most preferred is a polymer that is terminally mercapted with a treating agent after polymerization. In other words, a vinyl monomer is radically polymerized in the presence of a thiocarbonylthio compound to synthesize a polymer having a thiocarbonylthio group, followed by cleavage of the thiocarbonylthio group bond with a treating agent to produce a mercapto group. By doing so, a vinyl polymer having a mercapto group at the terminal can be obtained. The polymer having a mercapto group at the terminal obtained by RAFT polymerization will be described below.

  Although it does not specifically limit as a monomer used for the said RAFT polymerization, For example, the following compounds can be mentioned: Methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, acrylic acid t -Butyl, n-hexyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate, 2-methoxyethyl acrylate, 3-methoxybutyl acrylate, 2-hydroxyethyl acrylate, acrylic acid Such as 2-hydroxypropyl, glycidyl acrylate, 2-acryloyloxypropyldimethoxymethylsilane, 2-acryloyloxypropyltrimethoxysilane, 2,2,2-trifluoroethyl acrylate, and allyl acrylate. Rylic acid ester monomers; methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, t-butyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, methacrylic acid n-octyl, n-decyl methacrylate, n-dodecyl methacrylate, tridecyl methacrylate, stearyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, benzyl methacrylate, 2-methoxyethyl methacrylate, 3-methoxybutyl methacrylate, Methacrylic acid esters such as 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, glycidyl methacrylate, 2,2,2-trifluoroethyl methacrylate, and allyl methacrylate Monomers such as acrylic acid, methacrylic acid, sodium acrylate, potassium acrylate, sodium methacrylate, potassium methacrylate; styrene monomers such as styrene, α-methylstyrene, p-methylstyrene, p-methoxystyrene; acrylonitrile, Vinyl cyanide monomers such as methacrylonitrile; conjugated diene monomers such as butadiene, isoprene and chloroprene; halogen-containing vinyl monomers such as vinyl chloride, vinylidene chloride, tetrafluoroethylene, hexafluoropropylene and vinylidene fluoride; vinyl acetate , Vinyl ester monomers such as vinyl propionate, vinyl pivalate, vinyl benzoate, vinyl cinnamate; maleic anhydride, maleic acid, maleic acid monoester, and maleic acid die Ether, fumaric acid, fumaric acid monoester, unsaturated dicarboxylic acid compounds and derivatives thereof, such as fumaric acid diester; maleimide, methyl maleimide, ethyl maleimide, phenyl maleimide, maleimide compounds such as cyclohexyl maleimide.

  These monomers may be used alone or in combination. What is necessary is just to select the monomer to be used according to the required characteristic of the resin composition containing a metal ultrafine particle finally obtained.

  The RAFT polymerization method applied in the present invention is not particularly limited with respect to its form, and for example, bulk polymerization, solution polymerization, emulsion polymerization, suspension polymerization, fine suspension polymerization, and the like can be applied. The medium (solvent) used in cases other than bulk polymerization is not particularly limited, and those generally used in radical polymerization can be used. From the viewpoints of availability and ease of polymerization, water, toluene, ethyl acetate, butyl acetate, dimethylformamide, and methyl ethyl ketone are preferred.

  The RAFT polymerization may be carried out by a generally known method, but typically it is performed as follows. The above thiocarbonylthio compound, polymerization initiator, monomer, and medium (solvent) as necessary are placed in the reactor, and oxygen in the system is removed by a conventional method, followed by heating and stirring in an inert gas atmosphere. A characteristic of RAFT polymerization is that the molecular weight of the polymer to be obtained is determined according to the monomer / thiocarbonylthio compound charge ratio and the monomer reaction rate, so that a polymer having a desired molecular weight can be obtained.

  In the practice of the present invention, the vinyl polymer having a thiocarbonylthio group obtained by RAFT polymerization is treated with a treating agent to obtain a vinyl polymer having a mercapto group at one end. Although it does not limit as such a processing agent, A basic compound, a reducing agent, or a hydrogen-nitrogen bond containing compound is preferable at a point with high reaction efficiency.

Among the above-mentioned treatment agents, the basic compound is not particularly limited, but metal hydroxide, metal alkoxide, metal hydride, inorganic salt of strong base and weak acid, organometallic reagent, tertiary amine compound, alkali metal, alkaline earth Similar metals can be mentioned. No particular limitation is imposed on the reducing agent of the treatment agent include sodium hydride, lithium hydride, calcium _{hydride, LiAlH 4, NaBH 4, LiBEt} 3 H, hydrogen and the like.

  Among the above-mentioned treatment agents, the hydrogen-nitrogen bond-containing compound is not particularly limited. For example, ammonia, hydrazine, primary amine compound, secondary amine compound, amide compound, amine hydrochloride compound, hydrogen-nitrogen bond-containing compound Examples thereof include polymers and hindered amine light stabilizers (HALS).

  Among these compounds, a compound selected from a base and a hydrogen-nitrogen bond-containing compound is preferable in view of high reaction efficiency, and a hydrogen-nitrogen bond-containing compound is more preferable in view of easy handling. In view of ease of recovery and removal, monomethylamine, monoethylamine, dimethylamine, diethylamine, monobutylamine, dibutylamine, and cyclohexylamine are more preferable.

  The molecular weight of the vinyl polymer having a mercapto group at the end is not limited because the preferred range varies depending on the type of ultrafine particles used, the particle size, the type of polymer used, the amount of particles added, etc., but the progress of the polymerization reaction is easy. The number average molecular weight is preferably in the range of 1,000 to 100,000, more preferably in the range of 2,000 to 50,000 in terms of mercapto group introduction rate.

  The vinyl polymer having a mercapto group at the terminal produced by the RAFT polymerization has a molecular weight distribution (weight average molecular weight / number average molecular weight) of usually 1.5 or less, and generally 1.3 or less. When the molecular weight distribution is narrowed, there are advantages such as improved dispersibility of the ultrafine metal particles and excellent transparency, moldability and mechanical properties of the resin composition.

  The metal ultrafine particle-containing resin composition of the present invention may contain a thermoplastic resin other than a vinyl polymer having a mercapto group. Such a resin component may be mixed in advance when the metal ultrafine particles are synthesized by thermal decomposition, or may be added after the metal ultrafine particles are synthesized. When the metal ultrafine particles are synthesized and added and mixed, a suitable solvent may be used, or melt kneading may be used. The thermoplastic resin used in the present invention is not particularly limited, but it is possible to control the dispersibility and morphology of the metal ultrafine particles by adjusting the compatibility with the polymer having a mercapto group at the terminal. Become. For example, the ultrafine metal particles can be localized only in one phase of the co-continuous structure or the sea-island structure, or the ultrafine metal particles can be localized on the surface of the resin composition.

  Specific examples of the thermoplastic resin used in the present invention are not particularly limited, but aromatic vinyl resins such as polystyrene, vinyl cyanide resins such as polyacrylonitrile, chlorine resins such as polyvinyl chloride, and polymethyl methacrylate. Such as polymethacrylate resin and polyacrylate resin, polyolefin resin such as polyethylene, polypropylene and cyclic polyolefin resin, polyvinyl ester resin such as polyvinyl acetate, polyvinyl alcohol resin and their derivative resins, Obtained by polymerizing polymethacrylic acid resins, polyacrylic acid resins and their metal salt resins, polyconjugated diene resins, polymers obtained by polymerizing maleic acid, fumaric acid and their derivatives, and maleimide compounds. Polymers, polyester Resin, polyamide resin, polycarbonate resin, polysulfone resin, polyalkylene oxide resin, cellulose resin, polyphenylene ether resin, polyphenylene sulfide resin, polyarylate resin, thermoplastic polyimide resin, polyamideimide resin , Polyetherimide resins, polyether ketone resins, polyether ether ketone resins, polyvinyl ether resins, fluorine resins, liquid crystal polymers, and random block graft copolymers of these exemplified polymers. It is done.

  The heating temperature of the present invention is not less than the decomposition start temperature of the metal complex and less than the complete decomposition temperature of the metal complex. At this time, it is desirable that the temperature be lower than the decomposition start temperature of the polymer existing in the reaction system and lower than the boiling temperature of the reaction solvent. The decomposition start temperature of a metal complex refers to the temperature at which the organic component of the metal complex decomposes and weight loss begins, and the complete decomposition temperature refers to the temperature at which the organic component of the metal complex decomposes completely. This temperature can be measured by a method in which a metal complex having a small amount of an organic group is weighed in a container, and the weight change is measured while heating at a constant rate in an inert gas atmosphere using a thermogravimetric analyzer. Is possible.

  The heating time of the present invention can be appropriately selected according to the heating temperature and the like, and is not particularly limited, but is preferably 30 minutes to 2 hours. When the heating time is short, the content of the ultrafine metal particles in the produced resin composition is reduced, and when the heating time is long, the particle size of the ultrafine metal particles is enlarged, or the resin is degraded and the characteristics of the resin are deteriorated. .

  In producing the resin composition containing ultrafine metal particles of the present invention, it is preferable to stir in order to disperse the ultrafine metal particles uniformly. At this time, the stirring speed is not particularly limited, but it is preferable to set the stirring speed so that the inside of the system is uniformly stirred and an appropriate shear force is applied to the generated ultrafine metal particles. When there is a portion that is not uniformly stirred and is not locally stirred, coarse particles may be generated in that portion. In addition, when the stirring speed is very slow and no shear force is applied, the particle diameter of the metal ultrafine particles tends to increase. A specific preferable stirring speed is 100 rpm to 5000 rpm.

  The number average particle diameter of the metal ultrafine particles is not particularly limited, but is preferably in the range of 0.1 to 100 nm, more preferably 0.5 to 50 nm, and more preferably 1 to 20 nm in that the quantum characteristics of the metal ultrafine particles become remarkable. Further preferred.

  The number average particle diameter in the present invention means a number average particle diameter calculated by measuring the particle diameter of at least 100 particles with a ruler using a photograph taken with a transmission electron microscope. However, when the photograph of the particle | grains image | photographed with the electron microscope is not circular, after calculating the area which a particle occupies, it calculates using the circle diameter at the time of replacing with the circle | round | yen which has the same area.

When producing the resin composition containing ultrafine metal particles of the present invention, an appropriate organic solvent may be used. The use of an organic solvent is preferable because the stirring efficiency is improved and the particle size of the ultrafine metal particles and the dispersibility in the resin become uniform. Such an organic solvent is not particularly limited, but an organic solvent that decomposes upon heating or reacts with a compound in the system is not suitable. Desirable organic solvents have a boiling temperature higher than the decomposition temperature of the metal complex having an organic group, can dissolve a vinyl polymer having a mercapto group at its terminal, and have a metal complex having an organic group and a mercapto group as its terminal. It does not react with the vinyl-based polymer.

  Specific examples of such a preferable organic solvent include high-boiling ethers, amines having a long-chain alkyl group, and esters having a long-chain alkyl group, and high-boiling ethers are more preferable because of low reactivity.

  Although it does not specifically limit as a specific example of such a high boiling point ether compound, Dipentyl ether, Dihexyl ether, Diheptyl ether, Dioctyl ether, Hexyl pentyl ether, Diphenyl ether, Di (paratolyl) ether, Di (methallyl) ether, Di ( Orthotolyl) ether, di (2,3-dimethylphenyl) ether, di (2,6-)-dimethylphenyl) ether, di (2,4,6-trimethylphenyl) ether, 2-chloroethylphenylether, 2- Bromoethyl phenyl ether, 1,2-dimethoxybenzene, 1,2,3-trimethoxybenzene, 3,4,5-trimethoxytoluene, 1-methoxynaphthalene, 2-methoxynaphthalene, 1,2-dimethoxynaphthalene, diethylene glycol The Chill ether, diethylene glycol i-propyl ether, diethylene glycol n-butyl ether, dipropylene glycol dimethyl ether, dipropylene glycol di i-propyl ether, dipropylene glycol di n-butyl ether, triethylene glycol dimethyl ether, triethylene glycol methyl vinyl ether, tetraethylene glycol dimethyl ether , Tetraethylene glycol diethyl ether, polyethylene glycol dimethyl ether, polypropylene glycol dimethyl ether, polyethylene glycol diethyl ether, polyethylene glycol divinyl ether, 12-crown-4, 15-crown-5, 18-crown-6, dicyclohexyl-18-crown-6 Etc. Kill.

  Among these, dipentyl ether, dihexyl ether, diheptyl ether, dioctyl ether, hexyl pentyl ether, and diphenyl ether are preferable in terms of availability and high boiling point.

  The amount of the organic solvent of the present invention is not particularly limited as long as the viscosity can be adjusted so that the system can be uniformly stirred. The amount of the organic solvent is 1 to 100,000 parts by weight, and more preferably 100 to 10,000 parts by weight with respect to 100 parts by weight of the resin. When the amount of the organic solvent is less than 1 part by weight, the viscosity of the system is so high that it cannot be uniformly stirred, so that coarse metal particles may be generated. Moreover, it is not economical when the amount of the organic solvent exceeds 100,000 parts by weight.

  The heating atmosphere in the present invention is not particularly limited and can be produced in air, but produced in an inert gas such as nitrogen, argon, helium or carbon dioxide for the purpose of preventing deterioration of the resin component. It is desirable to do.

  In the present invention, a thermosetting resin can also be produced by crosslinking the ultrafine metal particle-containing resin composition. As a crosslinking method, a method in which a crosslinking agent is added to the produced resin composition containing ultrafine metal particles and heated, a method in which an electron beam or UV is irradiated, a crosslinking agent is added during production to produce ultrafine metal particles, and the resin is crosslinked. There are ways to do this. There are no particular restrictions on the crosslinking agent, but there are sulfur, peroxides, metal oxides, sulfur compounds having a disulfide group, quinone oximes, polyfunctional amines, and the like, which can be appropriately selected depending on the vinyl polymer having a mercapto group. it can.

  Furthermore, the resin composition of the present invention may contain a reinforcing filler as long as the characteristics of the present invention are not impaired. Thereby, heat resistance, mechanical strength, etc. can be improved. Such a reinforcing filler is not particularly limited, and examples thereof include fibrous fillers such as glass fiber, carbon fiber, and potassium titanate fiber; glass beads, glass flakes; talc, mica, kaolin, wollastonite, smectite, Silicate compounds such as diatomaceous earth; calcium carbonate, calcium sulfate, barium sulfate and the like. Of these, silicate compounds and fibrous fillers are preferred.

  Further, in order to make the resin composition of the present invention higher performance, only one kind of antioxidants such as phenolic antioxidants and thioether antioxidants; thermal stabilizers such as phosphorus stabilizers, etc. It is preferable to use in combination of two or more. Furthermore, as necessary, lubricants, mold release agents, plasticizers, flame retardants, flame retardant aids, anti-dripping agents, ultraviolet absorbers, light stabilizers, pigments, dyes, antistatic agents, which are generally well known. In addition, additives such as a conductivity imparting agent, a dispersing agent, a compatibilizing agent, and an antibacterial agent can also be used.

  The molding method of the resin composition of the present invention is not particularly limited, and generally used molding methods such as film molding, injection molding, blow molding, extrusion molding, vacuum molding, press molding, calendar molding, and foam molding. Etc. can be used. Moreover, the resin composition of this invention can be used conveniently for various uses.

Hereinafter, examples will be shown to further clarify the features of the present invention.

Measurement of the number average particle diameter of ultrafine metal particles in the resin composition: After making an ultrathin section from the obtained resin composition using an ultramicrotome (Ultracut UCT manufactured by Leica), a transmission electron microscope (TEM) Using (JEOL JEM-1200EX), the dispersion state of the ultrafine metal particles was photographed at a plurality of locations at a magnification of 10,000 to 400,000. The number average particle size of the particles was calculated by measuring the particle size of at least 100 particles in the obtained TEM photograph.

(Production Example 1) Production of polymethyl methacrylate having a mercapto group at one end Cumyldithio as a compound having a thiocarbonylthio group in a reactor equipped with a reflux condenser, a nitrogen gas introduction pipe, a thermometer, and a magnetic stirrer 0.1702 g of benzoate, 50.0 g of methyl methacrylate as a monomer, 100.0 g of toluene as a solvent, 0.021 g of 2,2′-azobisisobutyronitrile as a polymerization initiator, and a system while bubbling nitrogen gas Deoxygenation and nitrogen replacement were performed by a method of reducing the pressure inside. The polymerization was carried out by stirring at 90 ° C. for 5 hours.

  The temperature was lowered to 70 ° C., 0.132 ml of n-butylamine was added dropwise, and the mixture was stirred at 70 ° C. for 5 hours. After cooling, the polymer was deposited by pouring into 400 mL of methanol. Further, it was washed with methanol and dried to obtain 7.4 g of polymethyl methacrylate having a mercapto group at the terminal. GPC measurement of the obtained polymer was performed to determine the molecular weight and molecular weight distribution (Mn = 26000, Mw = 31000, Mw / Mn = 1.20).

(Production Example 2) Production of polystyrene having a mercapto group at one end In a 100 mL reactor equipped with a stirrer, thermometer, nitrogen gas introduction tube, reflux condenser, styrene 27.0 g, azobisisobutyronitrile 9 mg, And 68 mg of benzyldithiobenzoate were added, and the system was purged with nitrogen. The reaction was heated at 60 ° C. with stirring for 20 hours. After cooling the reaction solution to room temperature, it was poured into 200 mL of methanol to obtain 4.3 g of a polymer having Mw = 16200, Mn = 14000, and Mw / Mn = 1.16. As a result of 1H NMR measurement, it was confirmed that the thiocarbonylthio structure was introduced at one end of polystyrene and the introduction rate was 90% on the basis of one end. 2 g of the obtained polystyrene was dissolved in 40 mL of toluene, 0.5 g of Goodrite UV-3034 (manufactured by Goodrich) and 1 g of diethylamine were added at room temperature, and the mixture was stirred at 50 ° C. for 4 hours and then devolatilized under reduced pressure. From the 1H NMR measurement of the obtained polymer, it was confirmed that it was polystyrene having a mercapto group at one end.

Example 1
0.08 g of silver acetylacetonate (manufactured by Sigma Aldrich Japan Co., Ltd.) as a metal complex having an organic group, polymethyl having a mercapto group at one end obtained in Production Example 1 as a vinyl polymer having a mercapto group at its end 2.6 g of methacrylate (Mn = 26,000, Mn / Mw = 1.2), 10 ml of diphenyl ether (manufactured by Sigma-Aldrich Japan) as an organic solvent, 10 minutes at 150 ° C. under nitrogen and 10 minutes at 200 ° C. And heated at 250 ° C. for 20 minutes. After allowing to cool, 50 ml of anhydrous ethanol (Wako Pure Chemical Industries, Ltd.) as a poor solvent was added to the reaction solution to precipitate a black precipitate of the metal ultrafine particle-containing resin, and then centrifuged (6000 rpm, 10 minutes) to remove impurities. The supernatant solution containing was removed by decantation.

  20 ml of toluene (manufactured by Wako Pure Chemical Industries, Ltd.), which is a good solvent, was added to the precipitate of the precipitated resin containing ultrafine metal particles to dissolve the ultrafine metal particle-containing resin. Insoluble matters as impurities were removed by centrifugation (6000 rpm, 10 minutes). Again, 40 ml of absolute ethanol (manufactured by Wako Pure Chemical Industries, Ltd.) was added to the toluene solution of the resin containing ultrafine metal particles, centrifuged (6000 rpm, 10 minutes), and the supernatant solution containing impurities was removed by decantation. . To the precipitate of the ultrafine metal particle-containing resin, 20 ml of toluene (manufactured by Wako Pure Chemical Industries, Ltd.) was added to dissolve the ultrafine metal particle-containing resin, and insoluble matter was removed by centrifugation (6000 rpm, 10 minutes).

  The resin containing ultrafine metal particles dispersed in toluene is dispersed in a good solvent without aggregation and precipitation even after several months. One drop of a toluene solution of a resin containing ultrafine metal particles was dropped on a slide glass, dried, and then observed with an optical microscope (manufactured by Keyence Corporation, digital microscope VHX-100, 175 times). Although the film was brown and transparent, no particle agglomerates of a size that could be observed with an optical microscope were observed. The ultrafine metal particle-containing resin was obtained by drying the dispersion solution in a petri dish (diameter 5 cm). It was measured by observation with a transmission electron microscope that the average particle diameter was 7 nm.

(Example 2)
A zinc ultrafine particle-containing resin composition film was obtained in the same manner as in Example 1 except that 0.10 g of zinc stearate (manufactured by Sigma Aldrich Japan) was used as the metal complex having an organic group. The number average particle diameter of the ultrafine metal particles in the resin composition was about 10 nm.

(Example 3)
A platinum ultrafine particle-containing resin composition film was obtained in the same manner as in Example 1 except that 0.07 g of platinum acetylacetonate (manufactured by Sigma Aldrich Japan) was used as the metal complex having an organic group. The number average particle size of the ultrafine metal particles in the resin composition was about 15 nm.

Example 4
As a metal complex having an organic group, 0.08 g of silver acetylacetonate (manufactured by Sigma Aldrich Japan Co., Ltd.) is used, and the mercapto group obtained in Production Example 2 is used as a vinyl polymer having a mercapto group at one end. A silver ultrafine particle-containing resin composition film was obtained in the same manner as in Example 1 except that 2.6 g of polystyrene was used. The number average particle diameter of the ultrafine metal particles in the resin composition was about 9 nm.

(Example 5)
During the heat synthesis, polymethyl methacrylate (Sumitomo Chemical Co., Ltd., Sumipex LG-21, Mn = 44,000) 10.4 g was further added, and 50 ml of diphenyl ether was used as a solvent in the same manner as in Example 1. Thus, a silver ultrafine particle-containing resin composition film was obtained. The number average particle diameter of the ultrafine metal particles in the resin composition was about 10 nm.

(Comparative Example 1)
Implemented except that 2.6 g of polymethyl methacrylate (Sumitomo Chemical Co., Ltd., Sumipex LG-21, Mn = 44,000) was added in place of the vinyl polymer having a mercapto group at the terminal during the heat synthesis. In the same manner as in Example 1, a toluene solution of a resin containing ultrafine metal particles was obtained. A toluene solution of a resin containing ultrafine metal particles was dropped on a slide glass, dried, and then observed with an optical microscope. As a result, it was found that there were coarse metal particles of several μm.

Claims (9)

A metal complex having an organic group and a vinyl polymer having a mercapto group at the end obtained from a polymer synthesized by a reversible addition / desorption chain transfer polymerization method are dissolved in the vinyl polymer having the mercapto group at the end. A method for producing a resin composition containing ultrafine metal particles , comprising mixing in the presence of an organic solvent capable of heating, and heating the mixture to a temperature equal to or higher than a thermal decomposition temperature of the metal complex in a solution state to produce ultrafine metal particles . 2. The metal atom of the metal complex having an organic group is at least one element selected from the group consisting of transition metal elements, group 3B and group 4B metal elements, lanthanoids, and actinides. The manufacturing method of the metal ultrafine particle containing resin composition of description. The method for producing a resin composition containing ultrafine metal particles according to claim 1 or 2, wherein the metal complex having an organic group is at least one compound selected from the group consisting of an organic acid metal salt, an organic metal compound, and a metal alkoxide. . The method for producing a resin composition containing ultrafine metal particles according to any one of claims 1 to 3, wherein the molecular weight distribution of the vinyl polymer having a mercapto group at the terminal is 1.5 or less. The method for producing a resin composition containing ultrafine metal particles according to any one of claims 1 to 4, wherein the resin composition is thermoplastic. The manufacturing method of the metal ultrafine particle containing resin composition in any one of Claims 1-5 whose heating temperature is the temperature more than decomposition start temperature of the metal complex which has an organic group, and less than complete decomposition temperature. The method for producing a resin composition containing metal ultrafine particles according to any one of claims 1 to 6, wherein the number average particle diameter of the metal ultrafine particles is in the range of 0.1 nm to 100 nm. The production of the ultrafine metal particle-containing resin composition according to any one of claims 1 to 7, wherein the organic solvent capable of dissolving the vinyl polymer having a mercapto group at its terminal is a high-boiling ether compound. Method. The method for producing a resin composition containing ultrafine metal particles according to any one of claims 1 to 8, wherein the organic solvent is used in an amount of 1 to 100,000 parts by weight per 100 parts by weight of the vinyl polymer having a mercapto group at the terminal. .