Method for producing composite particles

Abstract

The present invention pertains to a method for producing composite particles having a polymer graft chain, the method comprising a step in which step 1 is performed in a powder state. (Step 1) A step for reacting inorganic particles with a silane compound having a polymerization starting group other than a halosulfonyl group to bond the polymerization starting group to the inorganic particles; (Step 2) A step for graft polymerizing a monomer in the presence of the inorganic particles to which the polymerization starting group is bonded. Provided is a production method with which it is possible to obtain composite particles having a graft density equivalent to that of conventional methods in which a solvent is used when a polymerization starting group is introduced, and which has excellent workability during production.

Description

TECHNICAL FIELD

[0001] The present application relates to a method for producing a composite particle. BACKGROUND

[0002] Hitherto, as a technique for bonding a polymer chain to an inorganic particle such as a metal particle, for example, a composite particle obtained by performing radical polymerization in the presence of a core particle mixed with a coupling agent having a polymerizable reactive group, a monomer component, and a polymerization initiator, thereby covering the surface of the core particle with a polymer layer has been known (Patent Document 1). It is known that by bonding an organic polymer chain to an inorganic particle, various functions such as vibration damping properties, antibacterial properties, and the like can be imparted to the particle (Patent Documents 2 and 3).

[0003] However, in the production of the composite particle described in Patent Documents 1 and 2, since a large amount of solvent is used at the time of introducing a polymerization initiation group, the amount of inorganic particles that can be handled per unit volume becomes small, and there is a problem that the production efficiency cannot be improved. In addition, there is a problem that when the amount of solvent used is reduced, a slurry having high viscosity is formed, resulting in difficulty in handling.

[0004] In view of the above, in the production of the composite particle described in Patent Document 3, since the amount of solvent used at the time of introducing a polymerization initiation group is small, handling as a powder is possible after the introduction of the polymerization initiation group, and it is considered that the above problem can be solved.

[0005] However, the present inventors and others have found that in the technology of Patent Document 3, the grafting density of the polymer grafting chain is unexpectedly low, and there is room for improvement. The higher the grafting density of the polymer grafting chain on the surface of the composite particle, the better the dispersibility of the composite particle, and the more functional molecules that can be introduced.

[0006] PRIOR ART DOCUMENTS

[0007] PATENT DOCUMENTS

[0008] Patent Document 1: Japanese Patent Application Publication No. 2005-120365

[0009] Patent Document 2: Japanese Patent Application Publication No. 2020-196877

[0010] Patent Document 3: Japanese Patent Application Publication No. 2010-018535 SUMMARY

[0011] The present application relates to the following 〔1〕 to 〔11〕.

[0012] 〔1〕 A method for producing a composite particle, which is a method for producing a composite particle having a polymer graft chain, the method comprising a process 1 in a powder state.

[0013] (Process 1) a process of bonding a polymerization initiation group to inorganic particles by reacting the inorganic particles with a silane compound having a polymerization initiation group other than a halogenated sulfonyl group,

[0014] (Process 2) a process of graft polymerization of a monomer in the presence of the inorganic particles to which the polymerization initiation group is bonded.

[0015] 〔2〕 The method for producing according to the above 〔1〕, wherein, among the components used in the process 1, the ratio ((A) / (B) [m 2 / g]) of the total (A [m 2 / g]) of the surface areas of the inorganic particles to the total (B [g]) of the masses of substances that are liquid at 25°C under 1 atm is 20 or more.

[0016] 〔3〕 The method for producing according to the above 〔1〕 or 〔2〕, wherein, among the components used in the process 1, the ratio ((A') / (B)) of the total (A' [g]) of the masses of the inorganic particles to the total (B [g]) of the masses of substances that are liquid at 25°C under 1 atm is 2 or more.

[0017] 〔4〕 The method for producing according to any one of the above 〔1〕 to 〔3〕, wherein a process of contacting a monomer with the inorganic particles to which the polymerization initiation group is bonded under active radical polymerization conditions is included.

[0018] 〔5〕 The method for producing according to any one of the above 〔1〕 to 〔4〕, wherein the graft density of the polymer graft chain on the surface of the composite particle is 0.001 chain / nm 2 or more and 5 chain / nm 2 or less.

[0019] 〔6〕 The method for producing according to any one of the above 〔1〕 to 〔5〕, wherein the amount of the silane compound having a polymerization initiation group other than a halogenated sulfonyl group is 0.1 parts by mass or more and 100 parts by mass or less with respect to 100 parts by mass of the inorganic particles.

[0020] 〔7〕 The method for producing according to any one of the above 〔1〕 to 〔6〕, wherein the polymerization initiation group is an α-haloacyl group, a halogenated alkyl group, or a halogenated alkylphenyl group.

[0021] 〔8〕 The production method according to any one of the above items 1 to 7, wherein in the step 1, one or more selected from the group consisting of ethanol, dichloromethane, toluene, acetone, tetrahydrofuran, methanol, butanol and butyl cellosolve is further used.

[0022] 〔9〕 The production method according to any one of the above items 1 to 8, wherein in the step 1, a catalyst is further used.

[0023] 〔10〕 A production method of a resin composition, comprising a step of mixing the composite particles obtained by the production method according to any one of the above items 1 to 9 with a resin.

[0024] 〔11〕 A resin composition comprising the composite particles obtained by the production method of the composite particles having a high molecular graft chain, comprising the step 1 in a powder state, and a resin.

[0025] (Step 1) a step of bonding a polymerization initiation group to inorganic particles by reacting the inorganic particles with a silane compound having a polymerization initiation group other than a halogenated sulfonyl group,

[0026] (Step 2) a step of graft polymerization of a monomer in the presence of the inorganic particles having the polymerization initiation group bonded thereto. DETAILED DESCRIPTION

[0027] The present application relates to a production method which can obtain a composite particle having a graft density equivalent to that of a conventional method using a solvent at the time of introducing a polymerization initiation group, and which is excellent in operability at the time of production.

[0028] According to the present application, it is possible to provide a production method which can obtain a composite particle having a graft density equivalent to or more than that of a conventional method using a solvent at the time of introducing a polymerization initiation group, and which is excellent in operability at the time of production.

[0029] The present inventors have focused on the kind of silane coupling agent at the time of introducing a polymerization initiation group to inorganic particles. It is presumed that the compound having a halogenated sulfonyl group used in Patent Literature 1 as a silane coupling agent has a tendency that the generation frequency of radicals is high, and thus the graft polymerization reaction proceeds too fast, as a result of which the graft density decreases. Thus, various silane coupling agents other than the compound having a halogenated sulfonyl group were investigated, and as a result, at the time of introducing a polymerization initiation group to inorganic particles using the silane coupling agent, the amount of liquid components such as a solvent was reduced as much as possible, whereby not only the operability at the time of production was improved, but also the graft density was unexpectedly improved.

[0030] <Production method of composite particles having a high molecular graft chain>

[0031] The method for producing the composite particles with the high molecular graft chain of the present application is a method for producing the composite particles with the high molecular graft chain, which includes the following step 1, in which the step 1 is performed in a powder state.

[0032] (step 1) a step of bonding the above polymerization initiation group to the inorganic particles by reacting the inorganic particles with a silane compound having a polymerization initiation group other than a halogenated sulfonyl group,

[0033] (step 2) a step of graft polymerization of a monomer in the presence of the inorganic particles to which the above polymerization initiation group is bonded.

[0034] In the present application, the so-called "powder" is a collection of particles, which is not confirmed to be in a liquid phase under visual observation, does not undergo caking, and has fluidity.

[0035] The so-called "fluidity" means that all of the following two points are satisfied.

[0036] • passes through a funnel (a funnel having a diameter of 5 mm at a lower outlet) without hindrance

[0037] • an angle of repose can be measured

[0038] In the present application, the angle of repose of the powder or the particles can be measured using a powder tester PT-R manufactured by HOSOKAWA MICRON Corporation.

[0039] In the present application, the angle of repose of the particles immediately after the completion of step 1 is preferably in the range of 25 degrees or more and 65 degrees or less. Thus, for example, if the angle of repose of the particles immediately after the completion of step 1 is in the range of 25 degrees or more and 65 degrees or less, it can be said that step 1 is performed in a powder state.

[0040] Note that the so-called "liquid" of the present application means a state having fluidity in which a change in volume is sufficiently small with respect to a change in pressure, and the viscosity at 25°C under 1 atm is preferably 10,000 mPa-s or less, more preferably 8,000 mPa-s or less, and further preferably 4,000 mPa-s or less. The above viscosity is a value measured at a prescribed rotation speed and a temperature of 25°C for 1 minute using a B-type viscometer using a rotor corresponding to the measurement range.

[0041] [Composite particles]

[0042] The so-called composite particles of the present application are particles in which a high molecular graft chain is bonded to the surface of inorganic particles.

[0043] [Inorganic particles]

[0044] As the inorganic particles, metal-based particles of metal oxides, metal oxide salts, metal hydroxides, metal carbonates, particles other than metals can be given. For example, one or two or more selected from the group consisting of silica, alumina, titania, zirconia, ferrite, magnesium oxide, silica titania, silicon carbide, silicon nitride, activated carbon, carbon black, carbon nanofiber, carbon nanotube, calcium carbonate, calcium oxide, barium sulfate, diatomite, bentonite, pearlite, mica, talc, and more preferably one or two or more selected from the group consisting of silica and silicates such as mica and talc, and further preferably silica can be given.

[0045] From the viewpoint of improving the reaction rate with the silane compound having a polymerization starting group other than a halogenated sulfonyl group, the inorganic particle surface can also be treated using a known method to increase the amount of hydroxyl groups, amino groups, and the like on the inorganic particle surface.

[0046] The shape of the particles is not particularly limited, and plate-like, granular, needle-like, fibrous, and the like can be given. In the present specification, in the case of being simply referred to as "particles", it refers to the particles used in the production of the composite particles.

[0047] The size of the inorganic particles is not particularly limited, however, from the viewpoint of improving the graft density of the polymer graft chain on the surface of the composite particles, the average particle diameter is preferably 1 nm or more, more preferably 3 nm or more, further preferably 10 nm or more, still further preferably 50 nm or more, yet further preferably 100 nm or more, on the other hand, preferably 100 μm or less, more preferably 10 μm or less, further preferably 1 μm or less, still further preferably 500 nm or less, yet further preferably 300 nm or less.

[0048] The size of the inorganic particles is a value measured using a Coulter counter method using Multisizer 3 (manufactured by Beckman Coulter, using a 20 μm orifice tube).

[0049] [Polymer graft chain]

[0050] As the polymer graft chain, a homopolymer or copolymer of a styrene-based monomer, a nitrile-based monomer, a (meth)acrylic acid-based monomer, an unsaturated olefin, a conjugated diene-based monomer, and the like can be given. A homopolymer or copolymer selected from one or two or more of acrylic acid, methacrylic acid, and derivatives thereof is preferred, a homopolymer or copolymer selected from one or two or more of methacrylic acid and derivatives thereof is more preferred, and polybutyl methacrylate is further preferred.

[0051] Regarding the graft density of the polymer graft chain on the surface of the composite particles, from the viewpoint of embodying functionality, 0.001 chains / nm 2 More preferably, 0.01 chains / nm2 Further preferably, the above is 0.1 chain / nm 2 On the other hand, from the viewpoint of easiness of grafting of the polymer chain, the above is preferably 5 chain / nm 2 More preferably, the above is 3 chain / nm 2 Further preferably, the above is 2 chain / nm 2 Further preferably, the above is 1 chain / nm 2 The graft density is measured by the method described in the Examples below.

[0052] The number average molecular weight of the polymer graft chain in the composite particle is preferably 5,000 or more, more preferably 10,000 or more, and further preferably 15,000 or more, from the viewpoint of controlling the film thickness of the polymer graft chain. Also, from the same viewpoint, it is preferably 1,000,000 or less, more preferably 500,000 or less, and further preferably 200,000 or less.

[0053] The number average molecular weight of the polymer graft chain is measured by the method described in the Examples below.

[0054] The glass transition temperature (Tg) of the polymer graft chain in the composite particle is preferably -30°C or more, more preferably -10°C or more, and further preferably 10°C or more, from the viewpoint of exhibiting functionality. Also, from the same viewpoint, it is preferably 80°C or less, more preferably 50°C or less, and further preferably 40°C or less.

[0055] The glass transition temperature (Tg) of the polymer graft chain in the composite particle can be controlled using the monomer, the molecular weight, and the molecular weight distribution used in the production of the composite particle.

[0056] The glass transition temperature (Tg) is measured by the method described in the Examples below.

[0057] The film thickness of the polymer graft chain in the composite particle is preferably 1 nm or more, more preferably 3 nm or more, and further preferably 5 nm or more, from the viewpoint of exhibiting functionality. Also, from the same viewpoint, it is preferably 1 μm or less, more preferably 100 nm or less, and further preferably 40 nm or less.

[0058] The film thickness of the polymer graft chain is calculated by the method described in the Examples below.

[0059] [Silane compound having a polymerization initiation group other than a halogenated sulfonyl group]

[0060] In the present application, the "polymerization initiation group other than a halogenated sulfonyl group" can be exemplified by an α-halogenated acyl group, a halogenated alkyl group, or a halogenated alkylphenyl group.

[0061] As specific examples of the α-haloacyl group, α-bromoacyl group, α-chloroacyl group can be given, and an α-haloacyl group in which the carbon number of the alkyl group constituting the haloacyl group is preferably 3 to 11 is preferable.

[0062] As specific examples of the haloalkyl group, bromoalkyl group, chloroalkyl group can be given, and a haloalkyl group in which the carbon number of the alkyl group constituting the haloalkyl group is preferably 3 to 11 is preferable.

[0063] As specific examples of the haloalkylphenyl group, bromoalkylphenyl group, chloroalkylphenyl group can be given, and a haloalkylphenyl group in which the carbon number of the alkyl group constituting the haloalkylphenyl group is preferably 3 to 11 is preferable.

[0064] As the "polymerization starting group other than halo sulfonyl group", from the viewpoint of being able to increase the graft density by introducing the polymerization starting group to the surface of the inorganic particle, an α-bromoacyl group is preferable.

[0065] The silane compound having a polymerization starting group other than halo sulfonyl group can be synthesized by reacting the "silane compound" and the "compound having a polymerization starting group" using a publicly known method.

[0066] For example, the silane compound having a bromoacyl group as a polymerization starting group (APTMS-Br) can be synthesized by reacting 3-aminopropyltrimethoxysilane and 2-bromoisobutyryl bromide as described in Synthetic Example 1 described later.

[0067] As the above silane compound which can be used in the present application, in addition to 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-(2-aminoethylamino)propyltrimethoxysilane, 3-(2-aminoethylamino)propyldimethoxysilane, 3-aminopropyldimethoxymethylsilane, [3-(6-aminohexylamino)propyl]trimethoxysilane, 3-aminopropyldiethoxymethylsilane, 3-(2-aminoethylamino)propyltriethoxysilane, trimethoxysilane, dimethoxy(methyl)silane, diethoxymethylsilane, triethoxysilane, tris(trimethylsiloxy)silane, and the like can be given.

[0068] As the above compound having a polymerization starting group which can be used in the present application, in addition to 2-bromoisobutyryl bromide, 2-chloroisobutyryl chloride, 2-bromopropionyl bromide, 2-chloropropionyl chloride, 2-bromo-2-phenylethyl bromide, 2-chloro-2-phenylethyl chloride, 2-bromo-2-methylpropionic acid allyl ester, 1-(2-bromo-2-methyl)propionic acid-5-hexenyl ester, 2-bromoisobutyric acid 10-undecenyl ester can be given.

[0069] A silane compound having a polymerization initiation group other than a halogenated sulfonyl group can also use a commercially available product in the field of the present application as a silane coupling agent, and examples thereof include 3-(trimethoxysilyl)propyl bromo-2-methylpropanoate and the like.

[0070] [Method for producing composite particles]

[0071] The composite particles are obtained by bonding a high molecular graft chain to the surface of the particles.

[0072] As for the method for bonding a high molecular graft chain to the surface of the particles, there is no particular limitation as long as it is a method capable of grafting a high molecular chain, however, an in-situ grafting (Grafting from) method in which a high molecular graft chain is polymerized from a polymerization initiation point on the surface of the particles is preferred.

[0073] As for the polymerization method, there is no particular limitation, however, examples thereof include radical polymerization, anionic polymerization, cationic polymerization and the like. Among them, from the viewpoint of easily controlling the molecular weight and the molecular weight distribution of the high molecular chain and the viewpoint of facilitating the grafting of various copolymers, active radical polymerization, active anionic polymerization, active cationic polymerization are preferred, and from the viewpoint of being applicable to a wide range of monomers, active radical polymerization is further preferred.

[0074] As the active radical polymerization method, an atom transfer radical polymerization method (ATRP method), a reversible addition fragmentation chain transfer polymerization method (RAFT method), an active radical polymerization method mediated by a nitroxide (NMP method) can be used, and from the same viewpoint, an atom transfer radical polymerization method (ATRP method) is preferred.

[0075] More specifically, as the method for producing composite particles, a production method including the following process 1 and process 2 can be exemplified.

[0076] [Process 1]

[0077] Process 1 is a process of bonding the above polymerization initiation group to the inorganic particles by reacting the inorganic particles with a silane compound having a polymerization initiation group other than a halogenated sulfonyl group. Specifically, the inorganic particles, the silane compound having a polymerization initiation group other than a halogenated sulfonyl group, and a catalyst, a solvent and the like used as necessary are added and mixed. A more suitable way is to mix the inorganic particles and the catalyst first, and then add the silane compound having a polymerization initiation group other than a halogenated sulfonyl group and a solvent used as necessary thereto, and mix them uniformly.

[0078] The reaction temperature when the silane compound reacts with the inorganic particles is preferably 25°C to 250°C, more preferably 150°C or lower, and further preferably 120°C or lower.

[0079] From the viewpoint of surface modification efficiency of the inorganic particles, the amount of silane compound having polymerization initiation groups other than halosulfonyl groups relative to 100 parts by mass of the inorganic particles is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, and even more preferably 1.0 parts by mass or more. On the other hand, from the viewpoint of suppressing reactions between silane compounds, it is preferably 100 parts by mass or less, more preferably 50 parts by mass or less, and even more preferably 40 parts by mass or less.

[0080] Regarding the reaction of the silane compound with inorganic particles, step 1 is preferably carried out in the powder state. This is because it increases the amount of inorganic particles that can be processed per unit volume, thereby improving manufacturing efficiency. To carry out step 1 in the powder state, for example, it is sufficient to minimize the amount of substances such as solvents that are liquid at 25°C and 1 atmosphere.

[0081] In this invention, the phrase "minimize as much of the amount of substance that is liquid at 25°C and 1 atmosphere" means that the total surface area (A [m]) of inorganic particles in the components used in step 1 is [missing information]. 2 The ratio of (A) / (B)[m] to the total mass of the substance that is liquid at 25°C and 1 atmosphere (B[g]) 2 The value of / g] is 20 or higher.

[0082] Here, from the viewpoint of performing step 1 in the powder state and from the viewpoint of increasing the grafting density of polymer grafted chains on the surface of composite particles, (A) / (B) [m 2 The value of (A) / (B)[m] is 20 or more, preferably 45 or more, more preferably 50 or more, and even more preferably 70 or more. On the other hand, from the viewpoint of the surface modification efficiency of inorganic particles, (A) / (B)[m] 2 The g / g is preferably 1000 or less, more preferably 800 or less, even more preferably 700 or less, and even more preferably 500 or less.

[0083] The total surface area of ​​the inorganic particles can be calculated using the method described in the embodiments described later.

[0084] Among the components used in step 1, substances that are liquid at 25°C and 1 atmosphere can be exemplified by solvents used in the field of this invention, catalysts that are liquid at 25°C and 1 atmosphere, and silane compounds having polymerization initiation groups other than halosulfonyl groups.

[0085] Examples of solvents that can be used in step 1 include organic solvents and / or solvents containing water. More specifically, examples include organic solvents such as ethanol, dichloromethane, toluene, acetone, tetrahydrofuran, methanol, butanol, and butyl cellosolve, as well as water. Among these, from the viewpoint of improving the dispersibility of the silane coupling agent with inorganic particles and increasing the grafting density of polymer grafted chains on the surface of the composite particles, solvents containing organic solvents are preferred. Specifically, solvents containing ethanol, toluene, tetrahydrofuran, and methanol are preferred, solvents containing ethanol, toluene, and tetrahydrofuran are more preferred, and solvents containing ethanol are even more preferred.

[0086] Regarding the mass ratio of organic solvent to silane coupling agent, from the viewpoint of performing step 1 in the powder state and from the viewpoint of increasing the grafting density of polymer grafted chains on the surface of composite particles, the ratio of organic solvent to silane coupling agent 1 is preferably 0.1 or more, more preferably 0.5 or more, further preferably 1 or more, even more preferably 2 or more, and preferably 10 or less, more preferably 8 or less, and even more preferably 4 or less.

[0087] Furthermore, from the viewpoint of improving the reactivity of silane coupling agents with inorganic particles and increasing the grafting density of polymer grafted chains on the surface of composite particles, the solvent in step 1 preferably includes water.

[0088] Regarding the mass ratio of water to silane coupling agent, from the viewpoint of performing step 1 in the powder state and from the viewpoint of increasing the grafting density of polymer grafted chains on the surface of composite particles, the mass ratio of water to silane coupling agent 1 is preferably 0.01 or more, more preferably 0.05 or more, further preferably 0.1 or more, even more preferably 0.2 or more, and preferably 1 or less, more preferably 0.5 or less, and even more preferably 0.3 or less.

[0089] When organic solvent and water are used together, from the viewpoint of performing step 1 in powder form, the mass ratio of alcohol and water to silane coupling agent is preferably 11 or less, more preferably 8.5 or less, and even more preferably 4.3 or less.

[0090] Examples of catalysts that can be used in step 1 include acids (e.g., acetic acid, trifluoroacetic acid, etc.), bases (e.g., ammonia, triethylamine, diethylamine, etc.), transition metals (e.g., Ti, Ni, Sn, etc.), or metals containing transition metals. Among these, bases are preferred from the viewpoint of good dispersibility with inorganic particles and increasing the grafting density of polymer grafted chains on the surface of composite particles, secondary amines and / or tertiary amines are more preferred, and tertiary amines are even more preferred.

[0091] Secondary amines are compounds formed by replacing two hydrogen atoms of ammonia with hydrocarbon groups. In this invention, dipropylamine, diisopropylamine, and dibutylamine are preferred examples. Tertiary amines are compounds formed by replacing all hydrogen atoms of ammonia with hydrocarbon groups. Diethylmethylamine, triethylamine, ethyldiisopropylamine, tripropylamine, and tributylamine are preferred examples.

[0092] In step 1, a catalyst may or may not be used. When using a catalyst, the amount of catalyst used can be the amount commonly used in the field of this invention, relative to the surface area of ​​the inorganic particles (1 nm). 2 From the viewpoint of surface modification efficiency of inorganic particles, 0.1 mol or more is preferred, more preferably 0.5 mol or more, and even more preferably 1 mol or more. On the other hand, from the viewpoint of suppressing reactions between silane compounds, 1000 mol or less is preferred, more preferably 100 mol or less, and even more preferably 10 mol or less.

[0093] Furthermore, among the components used in step 1, the ratio ((A') / (B)) of the total mass of inorganic particles (A'[g]) to the total mass of the liquid substance at 25°C and 1 atmosphere (B[g]) is preferably 2 or more, more preferably 3 or more, further preferably 5 or more, and even more preferably 10 or more, from the viewpoint of increasing the grafting density of polymer grafted chains on the surface of the composite particles. On the other hand, from the viewpoint of the surface modification efficiency of inorganic particles, (A') / (B) is preferably 100 or less, more preferably 80 or less, and even more preferably 60 or less.

[0094] Furthermore, regarding the total surface area of ​​inorganic particles (A [m]... 2 From the viewpoint of performing step 1 in the powder state, the relationship between (A') and (B) is more preferably that the value of (A') / (B) is within the above range and further satisfies log(A) ≥ -6.2log((A') / (B)) + 2.35.

[0095] After the reaction of the silane compound with the inorganic particles, the unreacted components are removed, thereby obtaining inorganic particles with polymerization initiation groups other than halosulfonyl groups bonded to their surface.

[0096] [Process 2]

[0097] In step 2, the monomer is grafted polymerized in the presence of inorganic particles bonded with polymerization initiation groups. Step 2 is preferably carried out under known conditions for living radical polymerization. The term "living radical polymerization conditions" in this specification refers to polymerization conditions appropriately selected by those skilled in the art for reliably and effectively carrying out living radical polymerization starting from polymerization initiation groups formed on the surface of inorganic particles bonded with polymerization initiation groups.

[0098] Examples of monomers used in step 2 include styrene monomers, nitrile monomers, (meth)acrylic monomers, unsaturated olefins, and conjugated diene monomers. In addition, monomers with specific groups on their side chains can also be used.

[0099] Specifically, examples include butyl methacrylate, butyl acrylate, ethyl methacrylate, ethyl acrylate, methyl methacrylate, methyl acrylate, acrylamide, acrylonitrile, 4-benzoylphenyl acrylate, benzyl methacrylate, cyclohexyl methacrylate, N,N-dimethylmethacrylamide, dodecyl acrylate, dodecyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, glycidyl methacrylate, n-hexyl methacrylate, methacrylamide, methacrylic acid, acrylic acid, octadecyl acrylate, phenyl acrylate, propyl methacrylate, vinyl acetate, methoxylated polyethylene glycol, methoxylated polyalkylene glycol, styrene, p-bromostyrene, 4-tert-butylstyrene, p-chlorostyrene, 4-iodostyrene, p-methoxystyrene, p-methylstyrene, sodium p-styrenesulfonate, vinyl benzyl chloride, etc.

[0100] The amount of monomer used in step 2 is relative to the surface area of ​​the inorganic particles bonded with polymerization initiation groups per m². 2 From the viewpoint of polymer introduction efficiency, it is preferable that the monomer content is 0.00001 mol or more, more preferably 0.0001 mol or more, and even more preferably 0.001 mol or more. On the other hand, from the viewpoint of polymerization control, relative to the unit specific surface area of ​​the inorganic particles bonded with polymerization initiation groups, it is preferable that the monomer content is 10 mol or less, more preferably 1 mol or less, and even more preferably 0.1 mol or less.

[0101] Graft polymerization can be carried out using copper halides such as copper bromide and copper chloride as catalysts.

[0102] There are no particular limitations on the ligand complexes used for copper halides. Examples include tris(2-(dimethylamino)ethyl)amine, N,N,N'',N''-pentamethyldiethylenetriamine, 1,1,4,7,10,10-hexamethyltriethylenetetramine, 1,4,8,11-tetramethyl-1,4,8,11-azacyclotetradecane, and bipyridine.

[0103] The amount of copper halide used as a catalyst is typically 0.1 to 1.0 parts by mass relative to 100 parts by mass of the monomer.

[0104] There are no particular limitations on the solvent used in polymerization, as long as it can dissolve the monomer. Examples include anethole, toluene, tetrahydrofuran, acetonitrile, methanol, 2-propanol, hexane, octane, dodecane, and 2,2,2-trifluoroethanol.

[0105] The reaction temperature is usually 30 to 200°C, preferably 50 to 150°C.

[0106] After graft polymerization, it is preferable to remove unreacted monomers and free polymers that are not bonded to inorganic particles using known methods.

[0107] <Resin Composition and Method for Manufacturing the Resin Composition>

[0108] The resin composition of the present invention comprises composite particles obtained by the manufacturing method described above and a resin.

[0109] [Resin]

[0110] From the viewpoint of processability, thermoplastic resins are preferred, while from the viewpoint of heat resistance, thermosetting resins are preferred.

[0111] Examples of thermoplastic resins include polyolefin resins, polyester resins, polyamide resins, ABS resins, polystyrene resins, polycarbonate resins, vinyl chloride resins, and acrylic resins. From the viewpoint of formability and ease of handling of the resulting resin composition, it is preferable to select one or more resins selected from polyolefin resins, polyamide resins, and ABS resins; more preferably, one or more resins selected from polyolefin resins; and even more preferably, polypropylene resin.

[0112] There is no particular limitation on the mass-average molecular weight of thermoplastic resins; however, thermoplastic resins with a mass-average molecular weight of 5,000 to 500,000 can be used.

[0113] Examples of thermosetting resins include polyurethane resins, urea-formaldehyde resins, phenolic resin foams, unsaturated polyester resins, alkyd resins, melamine resins, epoxy resins, silicone resins, and modified polyphenylene ether resins. Among these, modified polyphenylene ether resins are preferred from the viewpoint of exhibiting excellent low dielectric properties. Specific examples of modified polyphenylene ether resins include the resin described in WO2019 / 065941, which uses a modified polyphenylene ether compound and a crosslinking curing agent having carbon-carbon unsaturated double bonds in the molecule.

[0114] There is no particular limitation on the mass-average molecular weight of thermosetting resins; however, thermosetting resins with a mass-average molecular weight of 100 to 500,000 can be used.

[0115] From the viewpoint of formability, the amount of resin in the resin composition of the present invention is preferably 30% by mass or more, more preferably 40% by mass or more, and even more preferably 50% by mass or more. On the other hand, from the viewpoint of functionality, it is preferably 95% by mass or less, more preferably 80% by mass or less, and even more preferably 75% by mass or less. The amount when two or more resins are combined is the total amount of each resin.

[0116] From a functional perspective, the amount of composite particles in the resin composition of the present invention is preferably 1% by mass or more, more preferably 10% by mass or more, further preferably 20% by mass or more, and even more preferably 25% by mass or more. On the other hand, from the viewpoint of the dispersibility of the composite particles in the resin, it is preferably 75% by mass or less, more preferably 60% by mass or less, even more preferably 55% by mass or less, and even more preferably 50% by mass or less. The amount containing two or more types of composite particles is the total amount of each composite particle.

[0117] In the resin composition of the present invention, other than those mentioned above, chain extenders, plasticizers, organic crystal nucleating agents, inorganic crystal nucleating agents, hydrolysis inhibitors, flame retardants, antioxidants, hydrocarbon waxes, lubricants as anionic surfactants, ultraviolet absorbers, antistatic agents, antifogging agents, light stabilizers, pigments, mildew inhibitors, antibacterial agents, foaming agents, and other polymeric materials may be incorporated as other components.

[0118] [Method for manufacturing the resin composition]

[0119] The resin composition of this invention can be manufactured using a manufacturing method that includes a step of mixing composite particles obtained by the above-described manufacturing method with a resin.

[0120] For example, a manufacturing method that includes the process of melt-blending resin with composite particles can be cited. Melt-blending can be performed using known mixers such as closed kneaders, single-screw or twin-screw extruders, and open-roll mills. After melt-blending, the melt-blended mixture can be dried or cooled according to known methods. Alternatively, the raw materials can be pre-mixed uniformly using a Henschel mixer, high-speed mixer, or similar equipment before being used for melt-blending. The melt-blending temperature and time vary depending on the type of raw material used, but preferably, melt-blending at 170–240°C for 15–900 seconds is preferred.

[0121] Regarding the above-described embodiments, the present invention further discloses the following methods for manufacturing composite particles, methods for manufacturing resin compositions, and resin compositions.

[0122] [1] A method for manufacturing composite particles is a method for manufacturing composite particles having polymer grafted chains, comprising the following steps, wherein step 1 is performed in a powder state.

[0123] (Step 1) A step in which inorganic particles are reacted with a silane compound having polymerization initiation groups other than halosulfonyl groups, thereby bonding the polymerization initiation groups to the inorganic particles.

[0124] (Step 2) A step of grafting polymerization of monomers in the presence of inorganic particles bonded with the above-mentioned polymerization initiation groups.

[0125] [2] According to the manufacturing method described in [1], the powder is an aggregate of particles, which can be confirmed by visual observation that there is no liquid phase, no agglomeration, and has fluidity.

[0126] [3] According to the manufacturing method described in [1] or [2], the above-mentioned fluidity means that it passes through the funnel (the diameter of the lower outlet is 5 mm) without obstruction and the angle of repose is more than 25 degrees and less than 65 degrees.

[0127] [4] According to any one of the manufacturing methods described in [1] to [3], wherein the total surface area of ​​the inorganic particles among the components used in step 1 above (A [m]) 2 The ratio of (A) / (B)[m] to the total mass of the substance that is liquid at 25°C and 1 atmosphere (B[g]) 2 The value of / g] is 20 or more and 1000 or less.

[0128] [5] According to any one of [1] to [4], the manufacturing method described above (A) / (B) [m 2 [ / g] is 45 or higher and 1000 or lower.

[0129] [6] According to any one of [1] to [5], wherein the above (A) / (B) [m 2 [ / g] is 50 or more and 700 or less.

[0130] [7] According to any one of [1] to [6], wherein the above (A) / (B) [m 2 [ / g] is 70 or higher and 500 or lower.

[0131] [8] According to any one of [1] to [7], in the manufacturing method, the ratio of the total mass of inorganic particles (A' [g]) to the total mass of the liquid substance at 25°C and 1 atmosphere (B [g]) ((A') / (B)) is 2 or more and 100 or less.

[0132] [9] The manufacturing method described in any one of [1] to [8], wherein the above (A') / (B) is 3 or more and 60 or less.

[0133]

[10] The manufacturing method described in any one of [1] to [9], wherein (A), (B) and (A') satisfy the following formula.

[0134] log(A)≥-6.2log((A') / (B))+2.35

[0135]

[11] The manufacturing method described in any one of [1] to

[10] , wherein the size of the inorganic particles is defined as having an average particle size of 1 nm or more and 100 μm or less.

[0136]

[12] The manufacturing method described in any one of [1] to

[11] , wherein the size of the inorganic particles is defined as an average particle size of 3 nm or more and 10 μm or less.

[0137]

[13] The manufacturing method described in any one of [1] to

[12] , wherein the size of the inorganic particles is defined as having an average particle size of 50 nm or more and 1 μm or less.

[0138]

[14] The manufacturing method described in any one of [1] to

[13] , wherein the size of the inorganic particles is an average particle size of 100 nm or more and 500 nm or less.

[0139]

[15] The manufacturing method described in any one of [1] to

[14] , wherein a catalyst is further used in step 1.

[0140]

[16] According to the manufacturing method described in

[15] , wherein the catalyst is triethylamine, and the amount of triethylamine added is relative to the surface area of ​​the inorganic particles of 1 nm. 2 The concentration is between 0.1 mol and 1000 mol.

[0141]

[17] The manufacturing method according to any one of [1] to

[16] , wherein, in step 1, a solvent comprising an organic solvent and / or water is further used.

[0142]

[18] According to the manufacturing method described in

[17] , the organic solvent mentioned above includes one or more selected from ethanol, dichloromethane, toluene, acetone, tetrahydrofuran, methanol, butanol and butyl cellosolve, preferably one or more selected from ethanol, toluene, tetrahydrofuran and methanol, more preferably one or more selected from ethanol, toluene and tetrahydrofuran, and even more preferably ethanol.

[0143]

[19] According to the manufacturing method described in

[17] or

[18] , the mass ratio of the organic solvent to the silane coupling agent is 0.1 or more and 10 or less, preferably 0.5 or more and 8 or less, more preferably 1 or more and 4 or less, and even more preferably 2 or more and 4 or less.

[0144]

[20] According to the manufacturing method described in

[17] , the organic solvent is ethanol, and the mass ratio of ethanol to silane coupling agent is 0.1 or more and 10 or less relative to silane coupling agent 1, preferably 2 or more and 4 or less.

[0145]

[21] The manufacturing method according to any one of

[17] to

[20] , wherein the mass ratio of water to silane coupling agent is 0.01 or more and 1 or less, preferably 0.05 or more and 0.5 or less, more preferably 0.1 or more and 0.3 or less, and even more preferably 0.2 or more and 0.3 or less.

[0146]

[22] The manufacturing method described in any one of

[17] to

[21] , wherein when the organic solvent alcohol and water are used together, the mass ratio of alcohol to water relative to silane coupling agent is 11 or less, preferably 8.5 or less, more preferably 4.3 or less.

[0147]

[23] The manufacturing method according to any one of [1] to

[22] , wherein the amount of the silane compound having a polymerization initiation group other than a halosulfonyl group relative to 100 parts by mass of inorganic particles is 0.1 parts by mass or more and 100 parts by mass or less, preferably 0.5 parts by mass or more and 50 parts by mass or less, more preferably 1.0 parts by mass or more and 40 parts by mass or less.

[0148]

[24] The manufacturing method according to any one of [1] to

[23] includes a step of contacting the monomer with an inorganic particle bonded with a polymerization initiation group under living radical polymerization conditions.

[0149]

[25] The manufacturing method described in any one of [1] to

[24] , wherein the grafting density of the polymer grafted chains on the surface of the composite particles is 0.001 chains / nm. 2 Above and 5 chains / nm 2 The preferred value is 0.01 chains / nm. 2 Above and 3 chains / nm 2 Below, 0.1 chains / nm is preferred. 2 Above and 2 chains / nm 2 Hereinafter, 0.1 chains / nm is further preferred. 2 Above and 1 chain / nm 2 the following.

[0150]

[26] A method for manufacturing a resin composition, comprising a step of mixing composite particles obtained by any one of the manufacturing methods described in [1] to

[25] above with a resin.

[0151]

[27] According to the manufacturing method described in

[26] , the resin is a thermoplastic resin.

[0152]

[28] According to the manufacturing method described in

[27] , the thermoplastic resin is selected from one or more of polyolefin resin, polyester resin, polyamide resin, ABS resin, polystyrene resin, polycarbonate resin, vinyl chloride resin and acrylic resin.

[0153]

[29] According to the manufacturing method described in

[27] or

[28] , wherein the thermoplastic resin is a polypropylene resin with a mass-average molecular weight of 5,000 or more to 500,000 or less.

[0154]

[30] The manufacturing method described in

[26] is wherein the resin is a thermosetting resin.

[0155]

[31] According to the manufacturing method described in

[30] , the thermosetting resin is selected from one or more of polyurethane resin, urea-formaldehyde resin, phenolic resin foam, unsaturated polyester resin, alkyd resin, melamine resin, epoxy resin, silicone resin and modified polyphenylene ether resin.

[0156]

[32] According to the manufacturing method described in

[30] , the thermosetting resin is a modified polyphenylene ether resin.

[0157]

[33] A method for manufacturing composite particles having polymer grafted chains, comprising the following steps, wherein step 1 is performed in a powder state; composite particles obtained by the method for manufacturing composite particles; and a resin composition comprising a resin.

[0158] (Step 1) A step in which inorganic particles are reacted with a silane compound having polymerization initiation groups other than halosulfonyl groups, thereby bonding the polymerization initiation groups to the inorganic particles.

[0159] (Step 2) A step of grafting polymerization of monomers in the presence of inorganic particles bonded with the above-mentioned polymerization initiation groups.

[0160]

[34] A method for manufacturing composite particles, comprising step 1 of reacting inorganic particles with a silane compound having a polymerization initiation group other than a halosulfonyl group to bond the polymerization initiation group to the inorganic particles, and step 2 of grafting polymerization of monomers in the presence of inorganic particles bonded with the polymerization initiation group.

[0161] Among the components used in process 1, the total surface area of ​​inorganic particles (A [m]) 2 The ratio of (A) / (B)[m] to the total mass of the substance that is liquid at 25°C and 1 atmosphere (B[g]) 2The content of the composite particles is 20 or more; composite particles obtained by a method for manufacturing composite particles; and a resin composition containing a resin.

[0162]

[35] A composite particle is a composite particle with a polymer graft chain obtained by a manufacturing method comprising step 1, which involves reacting an inorganic particle with a silane compound having a polymerization initiation group other than a halogen sulfonyl group to bond the polymerization initiation group to the inorganic particle, and step 2, which involves grafting polymerization of a monomer in the presence of the inorganic particle with the polymerization initiation group bonded thereto, and is obtained by manufacturing step 1 in a powder state.

[0163]

[36] A resin composition comprising the composite particles described in

[35] above and a polypropylene resin with a mass-average molecular weight of 5,000 or more to 500,000 or less.

[0164]

[37] A resin composition comprising the composite particles described in

[35] above and a modified polyphenylene ether resin.

[0165] Example

[0166] Hereinafter, specific descriptions of the present invention will be given by way of examples, etc., but the present invention is not limited to the examples described below.

[0167] [Grafting density of polymer grafted chains on the surface of composite particles]

[0168] Regarding the grafting density (chains / nm) of polymer grafted chains on the surface of composite particles 2 The mass per unit area (g / nm) of the grafted chains bonded to the surface of the composite particles was measured. 2 The number-average molecular weight (Mn) of the grafted chain and the grafted chain can be calculated using the following formula.

[0169] Grafting density (chains / nm) 2 = [Mass of grafted chains per unit area (g / nm)] 2 [Number-average molecular weight of grafted chain] × (Avogadro's constant)

[0170] Here, the mass of the grafted chain is determined by thermogravimetric analysis (TG). More specifically, the composite particle to be tested is heated in atmosphere from 40°C to 500°C at a rate of 10°C / min, and the rate of weight loss at this point is measured. Furthermore, the "mass of the grafted chain per unit area" is calculated based on the specific surface area of ​​the inorganic particles that are the raw materials for the composite particle to be tested.

[0171] The number-average molecular weight of the grafted chains was determined using gel permeation chromatography (GPC) as shown below.

[0172] [Number-average molecular weight of polymer grafted chains in composite particles]

[0173] Regarding the number-average molecular weight of the polymer grafted chains in the composite particles, the number-average molecular weight of the polymer chains that are generated simultaneously during the composite particle manufacturing process and are not bonded to the composite particles is determined as the number-average molecular weight of the polymer grafted chains.

[0174] The number-average molecular weights were determined using gel permeation chromatography (GPC). The chromatographic column used in the GPC was TSKgel GMHHR-H+GMHHR-H (cationic) (manufactured by TOSOH). The solvent used was chloroform. The determination was performed using polystyrene as the conversion molecular standard at a flow rate of 1.0 mL / min and a column temperature of 40 °C.

[0175] [Methods for determining the specific surface area of ​​inorganic particles and calculating the total surface area]

[0176] The specific surface area of ​​inorganic particles was determined using the method of JIS Z 8833 (corresponding international standard: ISO 14488:2007).

[0177] That is, the amount of adsorbed gas [cm³] is determined based on the gas adsorption method according to JIS Z 8830:2001 (corresponding international standard: ISO 9277:2010) for particle samples collected based on JIS Z 8833. 3 The specific surface area of ​​inorganic particles was calculated using adsorption isotherms based on the so-called BET theory. In this specification, the value obtained using the static volumetric method derived from the BELSORP-miniII manufactured by BEL Corporation of Japan is used.

[0178] The total surface area is calculated as the product of the mass of the inorganic particles used and the specific surface area of ​​those inorganic particles.

[0179] [Glass transition temperature of polymer grafted chains in composite particles]

[0180] The determination was performed using the method described in JIS K 7121.

[0181] That is, using a differential scanning calorimeter (DSC7020 manufactured by Hitachi High Technology Co., Ltd.), the composite particles were heated from 40°C to 200°C at a rate of 10°C / min, and the heat capacity was measured. The glass transition temperature Tmg (°C) at the midpoint was determined in the DSC spectrum as the temperature at the point where a straight line equidistant from each baseline intersects the curve of the step-like transition portion of the glass transition.

[0182] [Film thickness of polymer grafted chains in composite particles]

[0183] The film thickness can be calculated using the following formula.

[0184] Regarding the polymer density in the formula, the polymer density of the polymer without bonded polymer graft chains generated simultaneously during the composite particle manufacturing process is defined as the polymer density of the polymer graft chains. The density was determined using a fully automated true density analyzer method according to JIS K 7112.

[0185] [Number 1]

[0186]

[0187] [Angle of repose of composite particles]

[0188] The angle of repose of the composite particles was measured using a powder analyzer (HOSOKAWA MICRON, PT-R).

[0189] Synthesis example 1

[0190] Synthesis of silane compounds with polymerization initiation groups other than halosulfonyl groups

[0191] 17.9 g of 3-aminopropyltrimethoxysilane (KBM-903, manufactured by Shin-Etsu Chemical Co., Ltd.), 100 mL of anhydrous tetrahydrofuran (THF), and 16.8 mL of anhydrous triethylamine (manufactured by Tokyo Chemical Industry Co., Ltd.) were added to a 500 mL pear-shaped flask. The mixture was cooled in an ice bath, and while maintaining the ice bath cooling at 0°C, 14.8 mL of 2-bromoisobutyryl bromide (BiBB) (manufactured by Tokyo Chemical Industry Co., Ltd.) was added dropwise and stirred for 4 hours. The solvent was then removed from the filtered liquid phase using an evaporator. The residue was dried at 50°C for 5 hours to obtain a silane compound having a bromoacyl group as a polymerization initiation group (this compound is abbreviated as "APTMS-Br"). This silane compound was used as a silane coupling agent.

[0192] The synthesis scheme of APTMS-Br described above is shown below.

[0193] [Chemistry 1]

[0194]

[0195] Example 1

[0196] [Process 1]

[0197] Add silica microparticles (Admatechs, SO-C2, average particle size 500 nm, specific surface area 5.5 m²) to the plastic bag. 250g of APTMS-Br and 0.23g of anhydrous triethylamine as a catalyst were mixed by hand from the outside of the bag for 5 minutes at room temperature. Then, 0.74g of APTMS-Br was added and mixed by hand from the outside of the bag for 5 minutes at room temperature (approximately 25°C, the same applies below). After mixing them for 5 minutes at room temperature using a pulverizer (manufactured by Iwatani Corporation), they were allowed to stand for 12 hours. The components in step 1 that are liquid at 25°C and 1 atmosphere are APTMS-Br and anhydrous triethylamine. Visual observation of the process in step 1 confirmed that the system remained in a powder state throughout step 1.

[0198] Subsequently, the silica particles were washed with ethanol, and then the silica particles were recovered by centrifugation and heated at 110°C for 1 hour to obtain silica particles with bromoacyl groups bonded as polymerization initiation groups.

[0199] [Process 2]

[0200] Add 6g of the above-mentioned particles bonded with polymerization initiation groups, 30mL of anethole (manufactured by Fujifilm and Hikari Pure Chemical Industries Co., Ltd.), and 90g of butyl methacrylate (manufactured by Fujifilm and Hikari Pure Chemical Industries Co., Ltd.) as monomers to a 500mL separable flask. After heating to 80°C and stirring thoroughly, bubbling with nitrogen for 1 hour is carried out.

[0201] In addition, an anisole solution was prepared by stirring 431 mg of Cu(I)Br (manufactured by Tokyo Chemical Industry Co., Ltd.) and 1040 mg of pentamethyldiethylenetriamine (manufactured by Tokyo Chemical Industry Co., Ltd.) in 2 mL of anisole.

[0202] Then, the entire volume of the anisole solution was poured into the flask, and living radical polymerization was initiated. Specifically, stirring was continued at 80°C for 10 minutes.

[0203] Subsequently, the silica microparticles grafted with polybutyl methacrylate were washed with methanol and recovered using a centrifuge. The grafting density on the surface of the obtained silica microparticles was 0.30 chains / nm. 2 The number-average molecular weight of the grafted chain is 33,000.

[0204] Example 2

[0205] [Process 1]

[0206] Add silica microparticles (Admatechs, SO-C2, average particle size 500 nm, specific surface area 5.5 m²) to the plastic bag. 2 Mix 50g of APTMS-Br and 0.23g of anhydrous triethylamine by hand for 5 minutes from the outside of the bag at room temperature. Add 0.74g of APTMS-Br and 0.74g of ethanol, and mix by hand for 5 minutes from the outside of the bag at room temperature.

[0207] The same process as in Example 1 was then performed to obtain silica microparticles bonded with polymerization initiation groups. Although a trace amount of ethanol was added as a solvent in this example, the system in step 1 was still in a powder state.

[0208] [Process 2]

[0209] Add 6g of the above-mentioned particles bonded with polymerization initiation groups, 30mL of anethole (manufactured by Fujifilm and Hikari Pure Chemical Industries Co., Ltd.), and 90g of butyl methacrylate (manufactured by Fujifilm and Hikari Pure Chemical Industries Co., Ltd.) as monomers to a 500mL separable flask. After heating to 80°C and stirring thoroughly, bubbling with nitrogen for 1 hour is carried out.

[0210] Then, the entire amount of the above-mentioned anethole solution was injected into the flask to initiate the same living radical polymerization as in Example 1, resulting in silica microparticles with grafted chains of polymethacrylic acid.

[0211] Example 3

[0212] The silica particles were replaced with other silica particles (manufactured by Admatechs, SO-C1, average particle size 200 nm, specific surface area 17.0 m²). 2 / g), and by changing the amounts of silane coupling agent and catalyst to those listed in Table 1, silica microparticles with grafted chains of polymethacrylic acid were obtained using the same method as in Example 1. No solvent was used in this example; therefore, the system in step 1 was in a powder state.

[0213] Example 4

[0214] In addition to replacing the silica microparticles with other silica microparticles (Degussa Aerosil 200, average particle size 12nm, specific surface area 200m²), 2 / g), and by changing the amounts of silane coupling agent and catalyst to those listed in Table 1, silica microparticles with grafted chains of polymethacrylic acid were obtained using the same method as in Example 1. No solvent was used in this example; therefore, the system in step 1 was in a powder state.

[0215] Example 5

[0216] Except for changing the silane coupling agent to another silane coupling agent with a bromoacyl group bonded as a polymerization initiation group (Tokyo Chemical Industry Co., Ltd., 3-(trimethoxysilyl)propyl 2-bromo-2-methylpropionate (abbreviated as "PTMS-Br")), and changing the amounts of silane coupling agent and catalyst to those listed in Table 1, silica microparticles having grafted chains of polymethacrylic acid were obtained using the same method as in Example 2. No solvent was used in this example, therefore the system in step 1 was in a powder state. It should be noted that the structure of PTMS-Br is shown below.

[0217] [Chemistry 2]

[0218]

[0219] Example 6

[0220] Except for changing the amount of ethanol to that recorded in Table 1, silica microparticles with grafted polymethacrylic acid chains were obtained using the same method as in Example 2. Although a trace amount of ethanol was added as a solvent in this example, the system in step 1 was still in a powder state.

[0221] Example 7

[0222] The silica particles were replaced with other silica particles (manufactured by Admatechs, SO-C1, average particle size 200 nm, specific surface area 17.0 m²). 2 / g), by changing the amounts of silane coupling agent and catalyst to those listed in Table 1, adding water as a solvent in addition to ethanol, and by using the same method as in Example 2, silica microparticles with grafted chains of polymethacrylic acid were obtained. Although trace amounts of ethanol and water were added as solvents in this example, the system in step 1 was still in a powder state.

[0223] Comparative Example 1

[0224] Silica nanoparticles (manufactured by Degussa, Aerosil 200, average particle size 12 nm, specific surface area 200 m²) were used. 2 8.0 g of silica nanoparticles were added to a three-necked flask, and the flask was purged with nitrogen. While stirring the silica nanoparticles, 3.6 g of 2-(4-chlorosulfonylphenyl)ethyltrimethoxysilane (hereinafter referred to as "Ts-Cl") was added dropwise. After the addition was complete, the mixture was stirred and reacted at 110 °C for 24 hours. Then, the pressure in the flask was reduced to remove unreacted material.

[0225] Subsequently, the silica particles were dried under reduced pressure at room temperature in a light-shielded environment to obtain silica particles with chlorosulfonyl groups as polymerization initiation groups. (Corresponding to step 1 in this invention) In this comparative example, the system in the step of obtaining inorganic particles bonded with polymerization initiation groups was in a powder state. It should be noted that Ts-Cl is a silane coupling agent having chlorosulfonyl groups (-SO2Cl) as halosulfonyl groups.

[0226] Add 2.0 g of chlorosulfonyl silica particles, 2.0 g of 4-vinylbenzyl chloride, 0.7 g of strychnine, and 0.1 g of copper bromide to a three-necked flask, and purge the flask with nitrogen. React at 60°C for 24 hours while stirring.

[0227] Tetrahydrofuran was added to the reaction product, followed by centrifugation, and the supernatant was discarded. The resulting solid was dried under reduced pressure to obtain silica particles with grafted chains of polyvinylbenzyl chloride.

[0228] Reference Example 1

[0229] Except for changing the amount of ethanol used as a solvent in step 1 to 200g, silica microparticles with grafted polymethacrylic acid chains were obtained using the same method as in Example 2. In this reference example, because a solvent was used, the system in step 1 was in a liquid state.

[0230] See Example 2

[0231] Except for changing the amount of ethanol used as a solvent in step 1 to 21.6 g, silica microparticles with grafted polymethacrylic acid chains were obtained using the same method as in Example 2. In this reference example, because a solvent was used, the system in step 1 was in a slurry state. Therefore, the viscosity of the mixture was high, and it required a significantly longer time than in Example 2 to mix the entire mixture evenly.

[0232] Example 8

[0233] Except for changing the amount of silane coupling agent to the amount listed in Table 3, silica microparticles with grafted polymethacrylic acid chains were obtained using the same method as in Example 1. No solvent was used in this example; therefore, the system in step 1 was in a powder state.

[0234] Example 9

[0235] Except for changing the amount of silane coupling agent to the amount recorded in Table 3, silica microparticles with grafted polymethacrylic acid chains were obtained using the same method as in Example 3. No solvent was used in this example; therefore, the system in step 1 was in a powder state.

[0236] Example 10

[0237] Except for changing the monomer from butyl methacrylate to styrene (manufactured by Fujifilm and Koujun Pharmaceutical Co., Ltd.), silica microparticles with polystyrene grafted chains were obtained using the same method as in Example 6. Although a trace amount of ethanol was added as a solvent in this example, the system in step 1 was still in a powder state.

[0238] Example 11

[0239] Except for changing the mixing device in step 1 from a pulverizing mixer to a high-speed mixer (manufactured by KAWATA Corporation), silica microparticles with polystyrene grafted chains were obtained using the same method as in Example 10. Although a trace amount of ethanol was added as a solvent in this example, the system in step 1 was still in a powder state.

[0240] Example 12

[0241] In addition to changing the silica microparticles to hollow silica (average particle size 1900nm, specific surface area 11.0m²), 2 Hollow silica with polystyrene grafted chains was obtained using the same method as in Example 1, except that the monomer was changed from butyl methacrylate to styrene (manufactured by Fujifilm and Kojun Pharmaceutical Co., Ltd.) and the amounts of silane coupling agent and catalyst were changed to those listed in Table 3. No solvent was used in this example; therefore, the system in step 1 was in a powder state.

[0242] It should be noted that the hollow silica used in Example 12 was manufactured as described below.

[0243] Emulsion A was obtained by mixing and stirring 388.6 g of ion-exchanged water, 200 g of dodecane (Kishida Chemical Company: Grade 1 n-dodecane), and 11.4 g of Quartamin 86W (Kao Corporation: containing 28% by mass of stearyltrimethylammonium chloride).

[0244] Add 13192.5g of ion-exchanged water, 138.1g of emulsion A, 125.6g of Quartamin 24P (manufactured by Kao Corporation: containing 27.5% by mass of lauryltrimethylammonium chloride), and 3120.8g of tetraethyl orthosilicate (manufactured by Asahi Kasei Wacker Silicon Co., Ltd.: TEOS999) to the reaction vessel, heat to 40°C while stirring, and then stir for 10 minutes to obtain preparation solution B.

[0245] Then, 221.5 g of AH212-CS (manufactured by Yokkaichi Synthetic Co., Ltd.: containing 50% by mass of dimethylbis(2-hydroxyethyl)ammonium hydroxide) and 711.6 g of Quartamin 24P were mixed uniformly to obtain preparation C. The entire amount of preparation C was added to the total amount of preparation B at a uniform rate, and then stirred at 40°C for 3 hours to obtain a turbid liquid D.

[0246] The resulting turbid liquid D was then filtered using 5°C filter paper (Advantech Toyo Co., Ltd.), washed with water, and dried at 110°C to obtain a white hollow silica particle precursor. The obtained hollow silica particle precursor was then calcined at 1100°C for 1 hour to obtain hollow silica.

[0247] The raw materials and results used in the above examples are summarized in the table below. It should be noted that the particles in Examples 1 to 12 immediately after step 1 passed through the funnel (a funnel with a diameter of 5 mm at the lower outlet) without obstruction.

[0248] [Table 1]

[0249]

[0250] [Table 2]

[0251]

[0252] [Table 3]

[0253]

[0254] The amount of silane coupling agent (parts by mass) relative to 100 parts by mass of inorganic particles.

[0255] The angle of repose of the particles immediately after process 1 is completed.

[0256] The grafting density (chains / nm) of polymer grafted chains on the surface of the obtained composite particles 2 ).

[0257] It should be noted that the solvents ethanol, dichloromethane, and water, the silane coupling agents APTMS-Br, PTMS-Br, and Ts-Cl, and the catalyst triethylamine are all liquid components at 1 atmosphere.

[0258] In Comparative Example 1, the same inorganic particles as in Example 4 were used to manufacture the composite particles, except that a silane compound having a chlorosulfonyl group as a polymerization initiation group was used. The grafting density of the polymer grafted chains on the surface of the resulting composite particles was 0.01 chains / nm.2 On the other hand, the grafting density of the polymer grafted chains on the surface of the inorganic composite particles manufactured in Example 4 was 0.18 chains / nm. 2 This result suggests that using silane compounds with halosulfonyl groups as polymerization initiation groups reduces the grafting density of polymer grafted chains on the surface of the resulting inorganic composite particles. The reason for this is speculated to be that halosulfonyl groups tend to generate free radicals frequently, thus accelerating the polymerization reaction and resulting in a lower grafting density.

[0259] Comparing Example 1 and Example 2, it can be seen that the composite particles obtained in Example 2 have a higher grafting density of polymer grafted chains on their surface. This can be attributed to the fact that, in step 1, the dispersibility of the silane coupling agent is improved in the presence of a good solvent such as ethanol.

[0260] Comparing Example 3 and Example 7, it can be seen that Example 7, which uses a smaller amount of silane coupling agent, has a higher grafting density of polymer grafted chains on the surface of the composite particles. This can be attributed to the fact that, in step 1, the presence of water in addition to ethanol enhances the reactivity of the silane coupling agent.

[0261] Reference Example 1 is an example of using ethanol as a medium in excess of a specified amount during the synthesis of inorganic particles bonded with polymerization initiation groups. A comparison of Examples 1 and 2, which used the same type of silica microparticles, with Reference Example 1 shows that the polymer grafting density on the surface of the inorganic composite particles produced in Reference Example 1 is lower than that in Example 1, which did not use a medium, and in Example 2, which used a medium in a specified amount.

[0262] Furthermore, as can be seen from Examples 10-11, composite particles with polymer grafted chains can also be manufactured using monomers other than butyl methacrylate, such as styrene.

[0263] Industrial availability

[0264] The composite particles obtained using the manufacturing method of the present invention can be used as fillers in resin compositions.

Claims

1. A method for manufacturing composite particles, comprising the following steps: step 1 is performed in a powder state. Step 1: A step in which inorganic particles are reacted with a silane compound having polymerization initiation groups other than halosulfonyl groups, thereby bonding the polymerization initiation groups to the inorganic particles. Step 2: A step of grafting polymerization of monomers in the presence of inorganic particles bonded with the polymerization initiation group.

2. The manufacturing method according to claim 1, wherein, In the components used in step 1, the ratio A / B of the total surface area A of the inorganic particles to the total mass B of the liquid substance at 25°C and 1 atmosphere is 20 or more, where A is in meters. 2 The unit of B is g, and the unit of A / B is m. 2 / g.

3. The manufacturing method according to claim 1 or 2, wherein, In the components used in step 1, the ratio of the total mass of inorganic particles A' to the total mass of the liquid substance at 25°C and 1 atmosphere B, A' / B, is 2 or more, where A' is in g and B is in g.

4. The manufacturing method according to any one of claims 1 to 3, It includes a process of contacting monomers with inorganic particles bonded with polymerization initiation groups under living radical polymerization conditions.

5. The manufacturing method according to any one of claims 1 to 4, wherein, The grafting density of polymer grafted chains on the surface of the composite particles is 0.001 chains / nm. 2 Above and 5 chains / nm 2 the following.

6. The manufacturing method according to any one of claims 1 to 5, wherein, The amount of silane compound having polymerization initiation groups other than halosulfonyl groups is 0.1 parts by mass and less than 100 parts by mass relative to 100 parts by mass of inorganic particles.

7. The manufacturing method according to any one of claims 1 to 6, wherein, The polymerization initiation group is α-haloacyl, haloalkyl, or haloalkylphenyl.

8. The manufacturing method according to any one of claims 1 to 7, wherein, In step 1, one or more of the following are further used: ethanol, dichloromethane, toluene, acetone, tetrahydrofuran, methanol, butanol and butyl cellosolve.

9. The manufacturing method according to any one of claims 1 to 8, wherein, In step 1, a catalyst is further used.

10. A method for manufacturing a resin composition, comprising a step of mixing composite particles obtained by the manufacturing method according to any one of claims 1 to 9 with a resin.

11. A resin composition comprising composite particles obtained by a method for manufacturing composite particles having polymeric grafted chains, including the steps of: step 1 being carried out in a powder state; and a resin. Step 1: A step in which inorganic particles are reacted with a silane compound having polymerization initiation groups other than halosulfonyl groups, thereby bonding the polymerization initiation groups to the inorganic particles. Step 2: A step of grafting polymerization of monomers in the presence of inorganic particles bonded with the polymerization initiation group.

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