JPWO2019022151A1 - Method for producing metal fine particle composite - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a more efficient production method for mass production of metal fine particle composites. SOLUTION: The method for producing a metal fine particle composite is represented by the formula [4]: [wherein R1 represents a hydrogen atom or a methyl group, and R2 to R4 are hydrogen atoms, which may be substituted. An alkyl group, an arylalkyl group or the like, two groups of R2 to R4 together represent an alkylene group, or R2 to R4 may form a ring together with a nitrogen atom to which they are bonded, X- represents an anion, n represents an integer of 5 to 100,000, and A1 represents a structure represented by the formula [2]. ##STR00002## (wherein A2 represents an alkylene group, Y1 to Y4 represent a hydrogen atom, an alkyl group, an alkoxy group, etc.)], and a hyperbranched polymer having an ammonium group at a terminal is represented by a reaction system. In the reaction system, a step of adding a metal salt in the presence of a reducing agent, or a step of directly adding metal fine particles into the reaction system is included. Characteristic manufacturing method. [Selection diagram] None

Description

The present invention relates to a production method for efficiently producing a composite of a hyperbranched polymer and metal fine particles.

A composite of a certain kind of hyperbranched polymer having an ammonium group at the molecular end and metal fine particles (hereinafter referred to as a metal fine particle composite), which is useful as an electroless plating material, is known. The hyperbranched polymer having an ammonium group at its terminal can be obtained, for example, by reacting a hyperbranched polymer having a halogen atom at the molecular terminal with an amine compound (Patent Document 1).

International Publication No. 2008/029688 pamphlet

Conventionally, in the process of manufacturing a metal fine particle complex, a step of filtering and isolating an ammonium salt (hyperbranched polymer having an ammonium group at the terminal) was once included in order to confirm the production. There is a problem in that the filterability may be poor, so that it takes time to manufacture the metal fine particle composite itself. Therefore, a more efficient manufacturing method is required for mass production of the metal fine particle composite.

The present inventors have conducted extensive studies to achieve the above object, after reacting a hyperbranched polymer having a halogen group at the terminal and an amine compound to obtain a hyperbranched polymer having an ammonium group at the molecular terminal, Without refining the reaction solution, the metal fine particles were directly added thereto to obtain a metal fine particle composite, and after the hyperbranched polymer having an ammonium group at the molecular end was isolated, it was reacted with the metal fine particles. The present invention has been completed by finding that a metal fine particle composite having the same quality can be obtained when a composite is obtained and when it is used as a gold electroless plating base agent, for example.

That is, the first aspect of the present invention is a method for producing a metal fine particle composite,
Formula [1]:
{In the formula [1], X represents a halogen atom, R ¹ independently represents a hydrogen atom or a methyl group, and A ¹ represents a formula [2]:
(In the formula, A ² represents a linear, branched or cyclic alkylene group having 1 to 30 carbon atoms which may include an ether bond or an ester bond. Y ^{1 to} Y ⁴ are each independently. , A hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a nitro group, a hydroxy group, an amino group, a carboxyl group or a cyano group). n is the number of repeating unit structures and represents an integer of 2 to 100,000. } The hyperbranched polymer having a halogen group at the terminal represented by the formula [3]
{R ^{2 to} R ⁴ are each independently a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, an arylalkyl group having 7 to 20 carbon atoms, or -(CH during ^{_{2 CH 2 O) m R 5}} ( wherein, ^{R 5} represents a hydrogen atom or a methyl group, m represents represents.) any integer from 2 to 100. The alkyl group and arylalkyl group may be substituted with an alkoxy group, a hydroxy group, an ammonium group, a carboxyl group or a cyano group. Also, two groups of R ^{2 to} R ⁴ are taken together to represent a linear, branched or cyclic alkylene group, or R ^{2 to} R ⁴ are together with a nitrogen atom to which they are bonded. May form a ring. } By reacting with an amine compound represented by the formula [4]
(R ¹ , R ^{2 to} R ⁴ , A ¹ and n have the same meanings as described above, and X ⁻ represents an anion of a halogen atom.) A hyperbranched polymer having an ammonium group at the terminal is used as a reaction system. The step of preparing in
Following the preparation process,
In the reaction system, a step of adding a metal salt in the presence of a reducing agent, or
A step of directly adding fine metal particles into the reaction system,
The present invention relates to a method for producing a metal fine particle composite, which comprises:
A second aspect relates to the method for producing a metal fine particle complex according to the first aspect, which includes a step of adding a metal salt in the presence of a reducing agent in the reaction system.
A third aspect relates to the method for producing a metal fine particle composite according to the first aspect or the second aspect, which uses an alcohol solvent as the reducing agent.
A fourth aspect relates to a metal fine particle composite obtained by using the method for producing a metal fine particle composite according to any one of the first to third aspects.

According to the present invention, there is provided an efficient method for producing a metal fine particle composite of a specific hyperbranched polymer and metal fine particles.

FIG. 1 is a diagram showing a ¹ H NMR spectrum of a hyperbranched polymer (HPS-Cl) having a chlorine atom at a molecular end produced in Production Example 1. FIG. 2 is a view showing a TEM image of a complex (Pd[HPS-N(Me) ₂ OctCl]) of a hyperbranched polymer having an ammonium group at a molecular end and Pd particles, which was produced in Example 1 (scale bar). : 20 nm). FIG. 3 is a view showing a TEM image of a complex (Pd[HPS-N(Me) ₂ OctCl]) of a hyperbranched polymer having an ammonium group at a molecular end and Pd particles produced in Example 1 (scale bar). : 5 nm).

In the present invention, the “metal fine particle composite” means that both of them coexist in the state of contacting or in close proximity to the metal fine particles by the action of the terminal ammonium group of the hyperbranched polymer having an ammonium group at the terminal represented by the formula [4]. However, it means that it has a particulate form. In other words, the “metal fine particle composite” is expressed as a composite having a structure in which the ammonium group of the hyperbranched polymer is attached or coordinated to the metal fine particles.
Therefore, the "metal fine particle composite" in the present invention is not limited to the one in which the metal fine particles and the hyperbranched polymer having an ammonium group at the end are bonded to form one composite as described above, And a mode in which the hyperbranched polymer independently exists without forming a binding portion.
Hereinafter, the present invention will be described in detail.

In the production method of the present invention, a hyperbranched polymer having a halogen group at the terminal represented by the formula [1] is reacted with an amine compound represented by the formula [3] to give the terminal represented by the formula [4]. A step of preparing a hyperbranched polymer having an ammonium group in a reaction system, and, following the preparation step, including a step of adding a metal salt in the presence of a reducing agent in the reaction system, or, Subsequent to the preparation step, a step of directly adding metal fine particles into the reaction system is included.

[Step of preparing a hyperbranched polymer having an ammonium group at a terminal represented by the formula [4] in a reaction system]
The hyperbranched polymer having a halogen group at the terminal used in this step is a polymer represented by the following formula [1].
In the above formula [1], R ^1's each independently represent a hydrogen atom or a methyl group.
X represents a halogen atom, n represents the number of repeating unit structures, and represents an integer of 2 to 100,000.
Examples of the halogen atom include chlorine atom, bromine atom, iodine atom and the like.

In the above formula [1], A ¹ represents a structure represented by the following formula [2].
In the above formula [2], A ² represents a linear, branched or cyclic alkylene group having 1 to 30 carbon atoms, which may have an ether bond or an ester bond.
Y ^{1 to} Y ⁴ each independently represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a nitro group, a hydroxy group, an amino group, a carboxyl group or a cyano group. Represent

Specific examples of the alkylene group of A ² include a linear alkylene group such as methylene group, ethylene group, n-propylene group, n-butylene group and n-hexylene group, isopropylene group, isobutylene group, 2-methyl group. Examples include branched alkylene groups such as propylene group. Examples of the cyclic alkylene group include alicyclic aliphatic groups having 3 to 30 carbon atoms, which have a monocyclic, polycyclic or crosslinked cyclic structure. Specific examples thereof include groups having a monocyclo, bicyclo, tricyclo, tetracyclo, or pentacyclo structure having 4 or more carbon atoms. For example, the structural examples (a) to (s) of the alicyclic moiety in the alicyclic aliphatic group are shown below.

Examples of the alkyl group having 1 to 20 carbon atoms represented by Y ^{1 to} Y ^{4 in} the above formula [2] include methyl group, ethyl group, isopropyl group, n-pentyl group, cyclohexyl group and the like. Examples of the alkoxy group having 1 to 20 carbon atoms include methoxy group, ethoxy group, isopropoxy group, n-pentyloxy group and cyclohexyloxy group. As Y ^{1 to} Y ⁴ , a hydrogen atom or an alkyl group having 1 to 20 carbon atoms is preferable.

The A ¹ preferably has a structure represented by the following formula [5].

The hyperbranched polymer having a halogen atom at the molecular end represented by the above formula [1] used in the present invention is a hyperbranched polymer having a dithiocarbamate group at the molecular end as described in WO 2008/029688. It can be manufactured. As the hyperbranched polymer having the dithiocarbamate group at the molecular end, a commercially available product can be used, and Hypertec (registered trademark) HPS-200 manufactured by Nissan Chemical Industries, Ltd. can be preferably used.

In addition, the amine compound used in this step is an amine compound represented by the following formula [3].
In formula [3], R ^{2 to} R ⁴ are each independently a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, or an arylalkyl having 7 to 20 carbon atoms. group, or _{- (CH 2 CH 2 O)} m R 5 ( wherein, ^{R 5} represents a hydrogen atom or a methyl group, m represents any integer of 2 to 100.) represents the.
The alkyl group and arylalkyl group may be substituted with an alkoxy group, a hydroxy group, an ammonium group, a carboxyl group or a cyano group. Also, two groups of R ^{2 to} R ⁴ are taken together to represent a linear, branched or cyclic alkylene group, or R ^{2 to} R ⁴ are together with a nitrogen atom to which they are bonded. May form a ring.

Examples of the linear alkyl group having 1 to 20 carbon atoms in R ^{2 to} R ⁴ include methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, n. -Heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, n-tridecyl group, n-tetradecyl group, n-pentadecyl group, n-hexadecyl group, n -Heptadecyl group, n-octadecyl group, n-nonadecyl group, n-eicosyl group and the like. For example, when the metal fine particle composite obtained by the production method of the present invention is used as an undercoating agent for electroless plating, the grouping agent having 8 or more carbon atoms is preferable because the undercoating agent is difficult to elute in the electroless plating solution. Particularly preferred is an n-octyl group.
Examples of the branched alkyl group include isopropyl group, isobutyl group, sec-butyl group, tert-butyl group and the like.
Examples of the cyclic alkyl group include a group having a cyclopentyl ring and a cyclohexyl ring structure.
Examples of the arylalkyl group having 7 to 20 carbon atoms in R ^{2 to} R ⁴ include a benzyl group and a phenethyl group.
Furthermore, examples of the linear alkylene group in which two groups of R ^{2 to} R ⁴ are combined include a methylene group, an ethylene group, an n-propylene group, an n-butylene group, an n-hexylene group and the like. To be Examples of the branched alkylene group include a methylethylene group (propylene group), butane-1,3-diyl group, 2-methylpropane-1,3-diyl group and the like.
Examples of the cyclic alkylene group include alicyclic aliphatic groups having a monocyclic, polycyclic or crosslinked cyclic structure having 3 to 30 carbon atoms. Specific examples thereof include groups having a monocyclo, bicyclo, tricyclo, tetracyclo, or pentacyclo structure having 4 or more carbon atoms. These alkylene groups may contain a nitrogen atom, a sulfur atom or an oxygen atom in the group.
And in the structure represented by the formula [3], the ring formed by R ^{2 to} R ⁴ together with the nitrogen atom bonded to them contains a nitrogen atom, a sulfur atom or an oxygen atom in the ring. Examples thereof include a pyridine ring, a pyrimidine ring, a pyrazine ring, a quinoline ring and a bipyridyl ring.

Examples of the combination of R ^{2 to} R ⁴ include [methyl group, methyl group, methyl group], [methyl group, methyl group, ethyl group], [methyl group, methyl group, n-butyl group], [methyl group Group, methyl group, n-hexyl group], [methyl group, methyl group, n-octyl group], [methyl group, methyl group, n-decyl group], [methyl group, methyl group, n-dodecyl group], [Methyl group, methyl group, n-tetradecyl group], [methyl group, methyl group, n-hexadecyl group], [methyl group, methyl group, n-octadecyl group], [ethyl group, ethyl group, ethyl group], [N-butyl group, n-butyl group, n-butyl group], [n-hexyl group, n-hexyl group, n-hexyl group], [n-octyl group, n-octyl group, n-octyl group] Among them, a combination of [methyl group, methyl group, n-octyl group], [n-octyl group, n-octyl group, n-octyl group] is preferable.

The amine compounds that can be used in this step include, as primary amines, methylamine, ethylamine, n-propylamine, isopropylamine, n-butylamine, isobutylamine, sec-butylamine, tert-butylamine, n-pentylamine, n. -Hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine, n-undecylamine, n-dodecylamine, n-tridecylamine, n-tetradecylamine, n-pentadecylamine , Aliphatic amines such as n-hexadecylamine, n-heptadecylamine, n-octadecylamine, n-nonadecylamine and n-eicosylamine; cycloaliphatic amines such as cyclopentylamine and cyclohexylamine; benzylamine, phenethylamine and the like Aralkylamines; aniline, pn-butylaniline, p-tert-butylaniline, pn-octylaniline, pn-decylaniline, pn-dodecylaniline, pn-tetradecylaniline and the like. Anilines, naphthylamines such as 1-naphthylamine and 2-naphthylamine, aminoanthracenes such as 1-aminoanthracene and 2-aminoanthracene, aminoanthraquinones such as 1-aminoanthraquinone, 4-aminobiphenyl and 2-aminobiphenyl, etc. Aminobiphenyls, 2-aminofluorene, 1-amino-9-fluorenone, 4-amino-9-fluorenone and other aminofluorenes, 5-aminoindane and other aminoindanes, 5-aminoisoquinoline and other aminoisoquinolines , Aromatic amines such as aminophenanthrenes such as 9-aminophenanthrene. Furthermore, N-(tert-butoxycarbonyl)-1,2-ethylenediamine, N-(tert-butoxycarbonyl)-1,3-propylenediamine, N-(tert-butoxycarbonyl)-1,4-butylenediamine, N -(Tert-butoxycarbonyl)-1,5-pentamethylenediamine, N-(tert-butoxycarbonyl)-1,6-hexamethylenediamine, N-(2-hydroxyethyl)amine, N-(3-hydroxypropyl) ) Amine compounds such as amine, N-(2-methoxyethyl)amine and N-(2-ethoxyethyl)amine.

Examples of the secondary amine include dimethylamine, diethylamine, di-n-propylamine, diisopropylamine, di-n-butylamine, diisobutylamine, di-sec-butylamine, di-n-pentylamine, ethylmethylamine, methyl- n-propylamine, methyl-n-butylamine, methyl-n-pentylamine, ethylisopropylamine, ethyl-n-butylamine, ethyl-n-pentylamine, methyl-n-octylamine, methyl-n-decylamine, methyl- n-dodecylamine, methyl-n-tetradecylamine, methyl-n-hexadecylamine, methyl-n-octadecylamine, ethylisopropylamine, ethyl-n-octylamine, di-n-hexylamine, di-n- Aliphatic amines such as octylamine, di-n-dodecylamine, di-n-hexadecylamine, di-n-octadecylamine; alicyclic amines such as dicyclohexylamine; aralkylamines such as dibenzylamine; diphenylamine and the like. Aromatic amines; nitrogen-containing heterocyclic compounds such as phthalimide, pyrrole, piperidine, piperazine, imidazole and the like can be mentioned. Further, bis(2-hydroxyethyl)amine, bis(3-hydroxypropyl)amine, bis(2-ethoxyethyl)amine, bis(2-propoxyethyl)amine and the like can be mentioned.

Examples of the tertiary amine include trimethylamine, triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine, tri-n-octylamine, tri-n-dodecyl. Amine, dimethylethylamine, dimethyl-n-butylamine, dimethyl-n-hexylamine, dimethyl-n-octylamine, dimethyl-n-decylamine, diethyl-n-decylamine, dimethyl-n-dodecylamine, dimethyl-n-tetradecyl Aliphatic amines such as amine, dimethyl-n-hexadecylamine, dimethyl-n-octadecylamine, dimethyl-n-eicosylamine; pyridine, pyrazine, pyrimidine, quinoline, 1-methylimidazole, 4,4'-bipyridyl, Nitrogen-containing heterocyclic compounds such as 4-methyl-4,4'-bipyridyl are mentioned.

The amount of the amine compound used in this step is 0.1 to 20 molar equivalents, preferably 0.5 to 10 molar equivalents, relative to 1 mole of halogen atoms of the hyperbranched polymer having a halogen atom at the molecular end. It is preferably 1 to 5 molar equivalents.

<Reaction with amine compound>
The reaction between the hyperbranched polymer having a halogen atom at the molecular end and the amine compound can be carried out in water or an organic solvent in the presence or absence of a base. The solvent used is preferably one that can dissolve the hyperbranched polymer having a halogen atom at the molecular end and the amine compound.
The solvent that can be used in this reaction may be any solvent that does not significantly inhibit the progress of this reaction, such as alcohols such as methanol, ethanol, isopropanol; N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc ), amides such as N-methyl-2-pyrrolidone (NMP), and dimethyl sulfoxide (DMSO) can be used. These solvents may be used alone or in combination of two or more. The amount used is 0.2 to 1,000 times by mass, preferably 1 to 500 times by mass, more preferably 5 to 100 times by mass, most preferably the mass of the hyperbranched polymer having a halogen atom at the molecular end. It is preferable to use 5 to 50 times the mass of the solvent.

In this reaction, it is preferable to sufficiently remove oxygen in the reaction system before the reaction is started, and the system may be replaced with an inert gas such as nitrogen or argon. The reaction conditions are appropriately selected from a reaction time of 0.01 to 100 hours and a reaction temperature of 0 to 300°C. The reaction time is preferably 0.1 to 72 hours and the reaction temperature is 20 to 150°C.

When a tertiary amine is used as an amine compound and this is reacted with a hyperbranched polymer having a halogen atom at the molecular end, the hyperbranched polymer represented by the formula [4] (in the above definition, R ^{2 to} R ² Polymers in which any of ⁴ represents a group other than a hydrogen atom) can be obtained.
When a primary amine or a secondary amine compound is used as an amine compound and a hyperbranched polymer having a halogen atom at the molecular end is reacted in the absence of a base, the corresponding secondary end of the hyperbranched polymer is Ammonium group terminal (-N ⁺ H ₂ R, -N ⁺ HRR') in which a primary amine (secondary amino group: -NHR) and a tertiary amine (tertiary amino group: -NRR') are protonated. A hyperbranched polymer of Further, even when the reaction is carried out using a base, by mixing with an aqueous solution of an acid such as hydrogen chloride, hydrogen bromide or hydrogen iodide in an organic solvent, the terminal secondary amine of the corresponding hyperbranched polymer is obtained. Also, an ammonium group-terminated hyperbranched polymer in which a tertiary amine is protonated is obtained.

The hyperbranched polymer having an ammonium group at the terminal has a weight average molecular weight Mw measured by gel permeation chromatography in terms of polystyrene of 1,000 to 5,000,000, preferably 1,000 to 500,000. Yes, more preferably 2,000 to 200,000, and most preferably 3,000 to 100,000. The degree of dispersion Mw (weight average molecular weight)/Mn (number average molecular weight) is 1.0 to 7.0, preferably 1.1 to 6.0, and more preferably 1.2 to 5. It is 0.

Specific examples of such a hyperbranched polymer having an ammonium group at the molecular end include a hyperbranched polymer represented by the following formula [4].
In the formula [4], R ¹ , R ^{2 to} R ⁴ , A ¹ and n have the same meanings as described above, and X ⁻ represents an anion (halide ion) of a halogen atom.

Preferably, the hyperbranched polymer having such an ammonium group at the molecular end has the following formula [6], wherein A ¹ has the structure represented by the above formula [5] and X ⁻ is a chloride ion. The hyperbranched polymer represented by
In the formula [6], R ¹ , R ^{2 to} R ⁴ and n have the same meanings as described above.

[Step of adding a metal salt in the reaction system in the presence of a reducing agent, or step of directly adding fine metal particles into the reaction system]
This step is performed subsequent to the step of preparing the hyperbranched polymer having an ammonium group at the terminal represented by the above formula [4] in the reaction system, and in the reaction system, a metal salt is added in the presence of a reducing agent. Or by directly adding fine metal particles.
That is, in the production method of the present invention, the hyperbranched polymer having an ammonium group at the terminal represented by the above formula [4] (hereinafter, simply referred to as hyperbranched polymer) is obtained by reacting the hyperbranched polymer having a halogen group at the terminal with an amine compound. (Also referred to as a polymer), after the hyperbranched polymer is not isolated from the reaction system, the reaction system (reaction solution) containing the hyperbranched polymer is added to the metal fine particle source (metal salt or metal salt or It is characterized in that metal fine particles) are added.
As will be described later, when a metal salt is added to the system in the presence of a reducing agent, the metal ion generated from the metal salt in the system is reduced by the action of the reducing agent to form a metal of the hyperbranched polymer and the metal fine particles. The fine metal particles will be obtained in the form of a fine particle composite. Further, instead of adding the reducing agent, the metal ions can be reduced by irradiating with ultraviolet rays to obtain a metal fine particle composite.

The amount of the metal salt or the fine metal particles added to the reaction system (reaction solution) containing the hyperbranched polymer having the ammonium group at the molecular end is 100 parts by mass of the hyperbranched polymer having the ammonium group at the molecular end. The amount is preferably 5 to 200 parts by mass (converted to the amount of metal). When the added amount of the metal salt (calculated as the metal amount) and the metal fine particles is less than 5 parts by mass, the organic substance content in the metal fine particle composite increases, and problems such as physical properties are likely to occur. If it exceeds 200 parts by mass, the dispersibility of the metal fine particles (in the case of a metal salt, the form after reduction) is insufficient. More preferably, it is 10 to 100 parts by mass. In practice, a value converted from the amount of the hyperbranched polymer having a halogen group at the terminal as a raw material can be treated as the amount of the hyperbranched polymer having an ammonium group at the molecular end.

The average particle size of the metal fine particles is preferably 1 to 100 nm. The above-mentioned "average particle size of the metal particles" means the average particle size of the metal particles when directly added to the reaction system, and the form of the metal particle composite of the hyperbranched polymer and the metal particles (composite). Both of the average particle diameters of the metal fine particles in the form (stabilized by) are mentioned.
The reason why the average particle diameter is preferably 1 to 100 nm is that when the average particle diameter of the metal fine particles exceeds 100 nm, the surface area decreases and the catalytic activity decreases. The average particle diameter is more preferably 75 nm or less, particularly preferably 1 to 30 nm.

The metal salt and the metal fine particles used in this step are not particularly limited, and as these metal species, iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), palladium (Pd), silver ( Examples thereof include Ag), tin (Sn), platinum (Pt), and gold (Au). These metals may be used alone or in combination of two or more, or may be an alloy. Among them, preferable metal species include palladium.

Examples of the metal salt (also used in the production of metal fine particles described later) include chloroauric acid, silver nitrate, copper sulfate, copper nitrate, copper acetate, tin chloride, platinum chloride, chloroplatinic acid, and Pt(dba) _2. [Dba=dibenzylideneacetone], Pt(cod) ₂ [cod=1,5-cyclooctadiene], Pt(CH ₃ ) ₂ (cod), palladium chloride, palladium acetate (Pd(OC(═O)CH ₃ ) ₂ ), palladium nitrate, Pd ₂ (dba) ₃ ·CHCl ₃ , Pd(dba) ₂ , rhodium chloride, rhodium acetate, ruthenium chloride, ruthenium acetate, Ru(cod)(cot) [cot=cyclooctatriene], Examples include iridium chloride, iridium acetate, Ni(cod) _{2 and the} like.

The metal fine particles are obtained by reducing metal ions by, for example, irradiating an aqueous solution of the above-mentioned metal salt with a high-pressure mercury lamp or adding a compound having a reducing action (so-called reducing agent) to the aqueous solution. Obtained by.
The reducing agent used for producing the metal fine particles is not particularly limited, and various reducing agents can be used, and it is preferable to select the reducing agent according to the metal species used and the like. Examples of the reducing agent that can be used include sodium borohydride, potassium borohydride, and other borohydride metal salts; lithium aluminum hydride, potassium aluminum hydride, cesium aluminum hydride, beryllium aluminum hydride, hydrogenation Aluminum hydride salts such as aluminum magnesium and aluminum calcium hydride; hydrazine compounds; citric acid and its salts; succinic acid and its salts; ascorbic acid and its salts; methanol, ethanol, isopropanol, polyols, etc. primary or secondary Tertiary alcohols; tertiary amines such as trimethylamine, triethylamine, diisopropylethylamine, diethylmethylamine, tetramethylethylenediamine [TMEDA], ethylenediaminetetraacetic acid [EDTA]; hydroxylamine; tri-n-propylphosphine, tri-n- Butylphosphine, tricyclohexylphosphine, tribenzylphosphine, triphenylphosphine, triethoxyphosphine, 1,2-bis(diphenylphosphino)ethane [DPPE], 1,3-bis(diphenylphosphino)propane [DPPP], 1 , 1'-bis(diphenylphosphino)ferrocene [DPPF], 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl [BINAP] and the like.
Further, as the metal fine particles, oxides of the metals listed above as the metal species may be used.

<Formation of metal fine particle composite by direct reduction method>
In the production method of the present invention, a metal fine particle composite of a hyperbranched polymer having an ammonium group at the end (hereinafter, hyperbranched polymer) and metal fine particles is, as described above, in the reaction system in which the hyperbranched polymer is prepared, By the step of adding the metal salt in the presence of the reducing agent, the metal ion generated from the metal salt in the system is reduced by the action of the reducing agent to form the metal fine particle complex. This step is also referred to as a "direct reduction method" because metal ions are directly reduced in the reaction system.

More specifically, in a reaction system containing a hyperbranched polymer, in the presence of the above-mentioned reducing agents, preferably primary or secondary alcohols (alcohol solvent) such as methanol, ethanol, isopropanol and polyol. Then, by adding the above-mentioned metal salt serving as a metal ion source and, if desired, a solvent, and reducing the metal ion with the above-mentioned reducing agent (primary or secondary alcohols), the target metal fine particle complex is obtained. Can be obtained.
In the above [step of preparing a hyperbranched polymer having an ammonium group at the terminal represented by the formula [4] in the reaction system], a primary or secondary alcohol such as methanol, ethanol or isopropanol as a solvent. When the above is used, these can be regarded as they are as the reducing agent in this step, and even in that case, the reducing agent may be added again in this step.
The solvent to be used is not particularly limited as long as it is a solvent capable of dissolving the metal ion (metal ion source) and the hyperbranched polymer at a required concentration or more, but specifically, alcohols such as methanol, ethanol, propanol, and isopropanol. Halogenated hydrocarbons such as methylene chloride and chloroform; Cyclic ethers such as tetrahydrofuran (THF), 2-methyltetrahydrofuran and tetrahydropyran; Nitriles such as acetonitrile and butyronitrile; N,N-dimethylformamide (DMF), N Amides such as methyl-2-pyrrolidone (NMP); sulfoxides such as dimethyl sulfoxide and the like, and a mixed solution of these solvents, preferably alcohols, halogenated hydrocarbons and cyclic ethers. , And more preferably, ethanol, isopropanol, chloroform, tetrahydrofuran and the like.
The temperature of the reduction reaction can be usually used in the range of 0°C to the boiling point of the solvent, and is preferably in the range of room temperature (about 25°C) to 60°C.

As a direct reduction method other than the above, a reaction system containing a hyperbranched polymer, a metal ion source, and optionally a solvent, by reacting in a hydrogen gas atmosphere, the target metal fine particle complex Obtainable.
Examples of the metal ion source used here include the above metal salts, hexacarbonylchromium [Cr(CO) ₆ ], pentacarbonyliron [Fe(CO) ₅ ], octacarbonyldicobalt [Co ₂ (CO) ₈ ]. , A metal carbonyl complex such as tetracarbonyl nickel [Ni(CO) ₄ ] can be used. Further, a zero-valent metal complex such as a metal olefin complex, a metal phosphine complex, and a metal nitrogen complex can be used.
The solvent to be used is not particularly limited as long as it is a solvent capable of dissolving the metal ion (metal ion source) and the hyperbranched polymer in a required concentration or more, and specifically, alcohols such as ethanol and propanol; methylene chloride, Halogenated hydrocarbons such as chloroform; cyclic ethers such as tetrahydrofuran, 2-methyltetrahydrofuran and tetrahydropyran; nitriles such as acetonitrile and butyronitrile; and mixed solutions of these solvents, and preferably tetrahydrofuran. ..
The temperature at which the metal ion source and the hyperbranched polymer are mixed is usually 0°C to the boiling point of the solvent.

As still another direct reduction method, a reaction system containing a hyperbranched polymer, a metal ion source, and optionally a solvent are added, and a thermal decomposition reaction is performed to obtain a target metal fine particle complex. You can
As the metal ion source used here, the above-mentioned metal salts, metal carbonyl complexes, other zero-valent metal complexes, and metal oxides such as silver oxide can be used.
The solvent used is not particularly limited as long as it is a solvent capable of dissolving the metal ion (metal ion source) and the hyperbranched polymer in a required concentration or more, and specifically, methanol, ethanol, n-propanol, isopropanol, ethylene. Alcohols such as glycols; Halogenated hydrocarbons such as methylene chloride and chloroform; Cyclic ethers such as tetrahydrofuran (THF), 2-methyltetrahydrofuran, tetrahydropyran; Nitriles such as acetonitrile and butyronitrile; Aroma such as benzene and toluene Examples thereof include group hydrocarbons and the like, and a mixed solution of these solvents, and toluene is preferable.
The temperature at which the metal ion source and the hyperbranched polymer are mixed can be usually used in the range of 0°C to the boiling point of the solvent, and preferably in the vicinity of the boiling point of the solvent, for example, 110°C (heating under reflux) in the case of toluene.

<Formation of metal fine particle complex by ligand exchange method>
Instead of the above direct reduction method, the metal fine particle composite may be formed by directly adding the metal fine particles into the reaction system.
In this method, specifically, a composite is formed by synthesizing metal fine particles that are stabilized to some extent by a lower ammonium ligand and then exchanging the ligand with a hyperbranched polymer.
In the ligand exchange method, the metal fine particles which have been stabilized to some extent by a lower ammonium ligand as a raw material can be synthesized by the method described in Journal of Organometallic Chemistry 1996, 520, 143-162 or the like. The reaction mixture solution of the obtained metal fine particles and the reaction system containing the hyperbranched polymer are mixed and stirred at room temperature (about 25° C.) or under heating to obtain the target metal fine particle composite.
The solvent to be used is not particularly limited as long as it is a solvent capable of dissolving the metal fine particles and the hyperbranched polymer in a required concentration or more, but specifically, alcohols such as ethanol, n-propanol and isopropanol; methylene chloride, Halogenated hydrocarbons such as chloroform; tetrahydrofuran (THF), cyclic ethers such as 2-methyltetrahydrofuran and tetrahydropyran; nitriles such as acetonitrile and butyronitrile; and a mixed solution of these solvents, and preferably tetrahydrofuran. Are listed.
The temperature at which the reaction mixture of the metal fine particles and the reaction system containing the hyperbranched polymer are mixed can be usually in the range of 0°C to the boiling point of the solvent, and preferably room temperature (about 25°C) to 60°C. Is the range.
In the ligand exchange method, it is possible to previously stabilize the metal fine particles to some extent by using a phosphine-based dispersant (phosphine ligand) in addition to the amine-based dispersant (lower ammonium ligand).

The hyperbranched polymer-metal fine particle composite thus obtained can be made into a solid form such as a powder through a purification treatment such as reprecipitation.

Hereinafter, the present invention will be described more specifically with reference to Examples, but the present invention is not limited to the following Examples.
In the examples, the apparatus and conditions used for sample preparation and physical property analysis are as follows.
(1) GPC (gel permeation chromatography)
Device: Tosoh Corp. HLC-8220GPC
Column: Showa Denko KK Shodex (registered trademark) KF-804L + KF-803L
Column temperature: 40°C
Solvent: Tetrahydrofuran Detector: UV (254 nm), RI
(2) ¹ H NMR spectrum device: JEM-L400 manufactured by JEOL Ltd.
Solvent: CDCl ₃
Internal standard: Tetramethylsilane (0.00ppm)
(3) ICP emission analysis (inductively coupled plasma emission analysis)
Device: Shimadzu Corporation ICPM-8500
(4) TEM (transmission electron microscope) image device: H-8000 manufactured by Hitachi High-Technologies Corporation

The abbreviations used are as follows.
HPS: Hyperbranched polystyrene [Hypertech (registered trademark) HPS-200 manufactured by Nissan Chemical Industries, Ltd.]
IPA: 2-propanol IPE: diisopropyl ether

[Production Example 1] Production of HPS-Cl
Into a 500 mL reaction flask, 27 g of sulfuryl chloride [manufactured by Kishida Chemical Co., Ltd.] and 50 g of chloroform were charged and stirred to uniformly dissolve them. This solution was cooled to 0° C. under a nitrogen stream.
Another 300 mL reaction flask was charged with 15 g of hyperbranched polymer HPS having a dithiocarbamate group at the molecular end and 150 g of chloroform, and stirred under a nitrogen stream until uniform.
From the 300 mL reaction flask in which the HPS/chloroform solution was charged under a nitrogen stream in the sulfuryl chloride/chloroform solution cooled to 0° C. described above, the solution was pumped to the temperature of the reaction solution. Of -5 to 5°C was added over 60 minutes. After the addition was completed, the reaction solution was stirred for 6 hours while maintaining the temperature at -5 to 5°C.
Furthermore, a solution of 16 g of cyclohexene [manufactured by Tokyo Chemical Industry Co., Ltd.] in 50 g of chloroform was added to this reaction liquid so that the temperature of the reaction liquid became -5 to 5°C. After the addition was completed, the reaction liquid was added to 1,200 g of IPA to precipitate a polymer. The white powder obtained by filtering this precipitate was dissolved in 100 g of chloroform, and this was added to 500 g of IPA to reprecipitate the polymer. The precipitate was filtered under reduced pressure and dried in vacuum to obtain 8.5 g of a hyperbranched polymer (HPS-Cl) having a chlorine atom at the molecular end as a white powder (yield 99%).
The ¹ H NMR spectrum of the obtained HPS-Cl is shown in FIG. 1. Since the peaks derived from the dithiocarbamate group (4.0 ppm, 3.7 ppm) disappeared, the obtained HPS-Cl was found to have almost all the dithiocarbamate groups at the ends of the HPS molecule replaced with chlorine atoms. It became clear. The weight average molecular weight Mw of the obtained HPS-Cl measured by GPC in terms of polystyrene was 14,000, and the dispersity Mw/Mn was 2.9.

[Example 1]
The reaction flask was charged with the HPS-Cl (763 mg) produced in Production Example 1 and chloroform (2.5 g), and the mixture was stirred until it became homogeneous. A solution of N,N-dimethyloctylamine (825 mg) in chloroform (1.25 g) prepared separately in a container was added to this solution, and then the inside of the container was charged with chloroform (1.25 g) to prepare the HPS- Rinse into Cl-containing solution. Further, ethanol (1.25 g) was added, and the mixture was heated with stirring at 60° C. for 8 hours under a nitrogen atmosphere. The resulting solution was cooled to room temperature (solution A).

A solution prepared by dissolving palladium acetate (1.43 g) in chloroform (8.45 g) was prepared in a separate container in advance, and this solution was added to the previously prepared solution A, and chloroform (800 mg) was used in the container. Then, the solution A was washed. This solution was heated and stirred at 50° C. for 6 hours under a nitrogen atmosphere, and then cooled to room temperature (solution B).

Solution B was poured into an IPE (185.7 g)/hexane (18.6 g) mixed solution for reprecipitation purification. The precipitated black powder was filtered off, and the powder was vacuum dried at 50° C. to obtain a complex of hyperbranched polymer having an ammonium group at the molecular end and Pd particles (Pd[HPS-N(Me) ₂ OctCl]) 1 0.27 g was obtained as a black powder.
From the result of ICP emission analysis, the Pd content of the obtained Pd[HPS-N(Me) ₂ OctCl] was 42.6% by mass.
TEM images of the obtained composite are shown in FIG. 2 and FIG. 3 (enlarged view of FIG. 2). According to TEM observation, the particle size of the metal fine particles stabilized by the obtained composite is 2 to 5 nm, which means that the metal fine particles are separated from the metal fine particles after isolation of the ammonium salt (hyperbranched polymer having an ammonium group at the end). It was about the same size as the complex prepared by the conventional method by the reaction.

[Reference Example 1] Preparation of electroless nickel plating solution Into a 2 L beaker, 40 mL of Kanigen (registered trademark) Blue Sumer [manufactured by Japan Kanigen Co., Ltd.] was charged, and pure water was added to make the total amount of the solution 200 mL. This solution was stirred to obtain an electroless nickel plating solution.

[Reference Example 2: Use as a base material for electroless plating]
It was dissolved in complexes of the hyperbranched polymer and the Pd particles having an ammonium group obtained in Example 1 at a molecular terminal _{(Pd [HPS-N (Me} ) 2 OctCl]) (100mg) and 1-propyl alcohol (10 g) An electroless plating base material was obtained. The obtained electroless plating base material was applied on a PET film (Toyobo Cosmoshine A-400) by bar coating. This was dried at 80° C. to obtain a PET film having a base layer on one side of the PET film.
This PET film was immersed in the electroless nickel plating solution prepared in Reference Example 1 heated to 90° C. for 2 minutes. When the PET film taken out was visually observed, it was confirmed that a nickel plating layer was obtained on the surface coated with the base agent (catalyst).

As described above, the metal fine particle composite obtained by the production method of the present invention had a particle diameter of about 2 to 5 nm as observed by TEM. Further, the metal fine particle composite obtained by the production method of the present invention is similar to the case of using the composite of the conventional production method obtained by the reaction with the metal fine particles after isolation of the ammonium salt. It was confirmed that a plating layer could be obtained when used as a material, and that it had a catalytic activity equivalent to that of a composite produced by a conventional production method.

Claims (4)

A method for producing a metal fine particle composite,
Formula [1]:
{In the formula [1], X represents a halogen atom, R ¹ independently represents a hydrogen atom or a methyl group, and A ¹ represents a formula [2]:
(In the formula, A ² represents a linear, branched or cyclic alkylene group having 1 to 30 carbon atoms which may include an ether bond or an ester bond. Y ^{1 to} Y ⁴ are each independently. , A hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a nitro group, a hydroxy group, an amino group, a carboxyl group or a cyano group). n is the number of repeating unit structures and represents an integer of 2 to 100,000. } The hyperbranched polymer having a halogen group at the terminal represented by the formula [3]
{R ^{2 to} R ⁴ are each independently a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, an arylalkyl group having 7 to 20 carbon atoms, or -(CH during ^{_{2 CH 2 O) m R 5}} ( wherein, ^{R 5} represents a hydrogen atom or a methyl group, m represents represents.) any integer from 2 to 100. The alkyl group and arylalkyl group may be substituted with an alkoxy group, a hydroxy group, an ammonium group, a carboxyl group or a cyano group. Also, two groups of R ^{2 to} R ⁴ are taken together to represent a linear, branched or cyclic alkylene group, or R ^{2 to} R ⁴ are together with a nitrogen atom to which they are bonded. May form a ring. } By reacting with an amine compound represented by the formula [4]
(R ¹ , R ^{2 to} R ⁴ , A ¹ and n have the same meanings as described above, and X ⁻ represents an anion of a halogen atom.) The reaction system is a hyperbranched polymer having an ammonium group at the terminal. The step of preparing in
Following the preparation step,
In the reaction system, a step of adding a metal salt in the presence of a reducing agent, or
A step of directly adding fine metal particles into the reaction system,
A method for producing a metal fine particle composite, comprising: The method for producing a metal fine particle complex according to claim 1, comprising a step of adding a metal salt to the reaction system in the presence of a reducing agent. The method for producing a metal fine particle complex according to claim 1, wherein an alcohol solvent is used as the reducing agent. A metal fine particle composite obtained by using the method for producing a metal fine particle composite according to claim 1.