Vinyl-modified organopolysiloxane, and radical polymerizable polymer or radical polymerizable copolymer using same as raw material

Abstract

[Problem] Provided are a vinyl-modified organopolysiloxane that is useful as a raw material for a radical polymerization reaction to be used in particular in a biodegradable polymer or copolymer, and a method for producing the vinyl-modified organopolysiloxane. The present invention furthermore provides a radical polymerizable polymer or a radical polymerizable copolymer that uses the vinyl-modified organopolysiloxane as at least part of a starting raw material, the use thereof, and a production method therefor. [Solution] A vinyl-modified organopolysiloxane having a polyorganosiloxane structure and having, in each molecule, two or more vinyl-modified groups (RAc) represented by -R1-C(=O)-O-CH=CHR2 (in the formula, R1 is a C4-20 divalent organic group, and R2 is a hydrogen atom or a methyl group) bonded to silicon atoms; a radical polymerizable polymer or a radical polymerizable copolymer (in particular, silicone elastomer particles) that uses the vinyl-modified organopolysiloxane as a raw material; and the use of these.

Description

Vinyl-modified organopolysiloxane, and radically polymerizable polymers or copolymers made from the same

[0001] The present invention relates to a vinyl-modified organopolysiloxane that has multiple vinyl-modified groups (functional groups having a vinyloxycarbonyl structure via a spacer of a certain chain length) bonded to specific silicon atoms within the molecule and is useful as a raw material for radical polymerization reactions, and a production method thereof characterized by transvinylation of the carboxylic acid-modified groups with vinyl acetate.The present invention also relates to a radical-polymerizable polymer or copolymer (especially including silicone elastomer particles) made from the vinyl-modified organopolysiloxane as a raw material, as well as its applications, production methods, and uses.

[0002] Organosilicon compounds containing one vinyloxycarbonyl group in the molecule are known, and because the vinyloxycarbonyl group is radically polymerizable, they are known to be used as polymer raw materials through homopolymerization or copolymerization reactions (for example, Patent Document 1 and Non-Patent Document 1). However, while these documents disclose so-called monomer raw materials, they do not specifically disclose compounds that have multiple vinyloxycarbonyl groups in the molecule via spacers of a specific chain length and that contain an organopolysiloxane structure.

[0003] On the other hand, in recent years, including the so-called microplastics problem, polymer or copolymer materials that persist in nature without decomposing at least in the short term have begun to be avoided industrially, and there is concern that polymers, copolymers, gels, particles, etc. containing such polymers and copolymers obtained by radical polymerization of monomer materials having a radically polymerizable functional group such as a vinyloxycarbonyl group bonded to a silicon atom via a short spacer having three or fewer carbon atoms will not decompose at least in the short term. Therefore, in order to reduce the risk to the global environment, there is a strong demand for reactive raw materials whose polymerization reaction products are biodegradable and which can be easily produced industrially.

[0004] Meanwhile, the present applicant has focused on the biodegradability issue inherent in conventional silicone elastomer particles, and has proposed silicone elastomer particles, as described in Patent Document 2, which have a structure in which an organopolysiloxane having at least three (meth)acryloxy group-containing organic groups as a base component is crosslinked with a divalent organic group having a partial structure formed by radical polymerization of vinyl acetate. These silicone elastomer particles are expected to be highly biodegradable, and compared with conventional silicone elastomer particles, they have reduced tendency to aggregate over time and give a smaller average secondary particle size, which has succeeded in realizing the properties of excellent dispersibility, ease of handling as a cosmetic raw material, storage stability, and stability in incorporation into systems.

[0005] However, organopolysiloxanes containing (meth)acryloxy-containing organic groups still have room for improvement in terms of industrial productivity and structural optimization as radically polymerizable raw materials for biodegradable polymers or copolymers.

[0006] Japanese Patent Publication No. 01-316388 International Patent Application PCT / JP2021 / 46142

[0007] Ego Proizvodnykh (1968), 291-4. Language: Russian, Database: CAPLUS

[0008] The present invention has been made to solve the above-mentioned problems, and provides a vinyl-modified organopolysiloxane useful as a starting material for radical polymerization reactions, particularly for use in biodegradable polymers or copolymers, and a method for producing the same. Furthermore, the present invention also provides a radical-polymerizable polymer or copolymer that uses the vinyl-modified organopolysiloxane as at least a part of the starting material, as well as uses and methods for producing the same.

[0009] In order to solve the above problems, the present inventors have conducted extensive research and have found that a compound having a -R bonded to a silicon atom in a molecule is １ -C(=O)-O-CH=CHR ２ (In the formula, R １ is a divalent organic group having 4 to 20 carbon atoms, and R ２is a hydrogen atom or a methyl group), Ａｃ ) and has two or more -(R ３ ２ SiO) ｎ - (wherein, R ３ The inventors have found that the above-mentioned problems can be solved by a vinyl-modified organopolysiloxane having a polyorganosiloxane structure represented by the formula:

[0010] Similarly, the present inventors have discovered that the above-mentioned problems can be solved by a method for producing a vinyl-modified organopolysiloxane, which includes a step of subjecting a specific carboxylic acid-modified organopolysiloxane to a transvinylation reaction with a vinyl carboxylate compound in the presence of a palladium metal catalyst, and have arrived at the present invention.

[0011] The present inventors also discovered that the above-mentioned problems can be solved by using a radically polymerizable polymer or copolymer, particularly silicone elastomer particles, that contains the above-mentioned vinyl-modified organopolysiloxane as at least a portion of the starting material, and thus arrived at the present invention. Furthermore, the present inventors also discovered that the above-mentioned problems can be solved by using cosmetic ingredients, organic resin additives, cosmetic materials, or organic resins that contain these radically polymerizable polymers or copolymers, and thus arrived at the present invention.

[0012] The present invention provides a vinyl-modified organopolysiloxane useful as a starting material for radical polymerization reactions, particularly for biodegradable polymers or copolymers, and a method for producing the same. Furthermore, the present invention also provides a radical-polymerizable polymer or copolymer that uses the vinyl-modified organopolysiloxane as at least a part of the starting material, as well as uses and methods for producing the same.

[0013] [Vinyl-modified organopolysiloxane] The vinyl-modified organopolysiloxane according to the present invention has, in the molecule, a —R １ -C(=O)-O-CH=CHR２ A vinyl modified group (R Ａｃ ) and has two or more -(R ３ ２ SiO) ｎ The vinyl-modified organopolysiloxane has a polyorganosiloxane structure represented by the formula:

[0014] The vinyl-modified group (R Ａｃ ) is a compound in which a methacryloxycarbonyl group or a vinyloxycarbonyl group is bonded to a silicon atom and a spacer having a certain chain length, R １ The vinyl-modified organopolysiloxane of the present invention has a vinyl-modified group (R Ａｃ ) is a group having two or more, preferably 2 to 20, more preferably 2 to 15. Ａｃ The bonding site of the vinyl-modified group (R) may be either a side chain or a terminal of the organopolysiloxane. However, in the case of transvinylation of a carboxylic acid-modified group, which will be described later, it is necessary to bond the vinyl-modified group (R) to the side chain site due to the relationship with the precursor raw material. Ａｃ ) may be easily synthesized.

[0015] In the formula, R １ is a divalent organic group having 4 to 20 carbon atoms, and is a functional group that acts as a spacer between the methacryloxycarbonyl group or vinyloxycarbonyl group and the Si atom. If this length is too short, biodegradability may decrease, particularly when used as a raw material for biodegradable polymers, while if it is too long, the polymer or copolymer obtained by radical polymerization of this vinyl-modified organopolysiloxane may lose the feel and sensation of use that are characteristic of silicone, and may not be able to achieve soft properties. １ is preferably an alkylene group having 4 to 20 carbon atoms, and particularly preferably an alkylene group having 6 to 15 carbon atoms.

[0016] In the formula, R ２ is a hydrogen atom or a methyl group, and is a functional group that provides a vinyloxycarbonyl group or a methacryloxycarbonyl group.

[0017] In the formula, n is the number of repeating diorganosiloxane units, and n is a number in the range of 1 to 1000. From the viewpoint of flexibility of the resulting radical polymerizable polymer or copolymer, n may be a number in the range of 50 to 750. ３ represents an unsubstituted or halogen-substituted alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 22 carbon atoms, or a hydroxyl group, and may be industrially a methyl group or a phenyl group.

[0018] Such vinyl-modified organopolysiloxanes have a vinyl-modifying group (R Ａｃ ), which is preferably a dimethylpolysiloxane having the following structural formula: Suitable examples include vinyl-modified organopolysiloxanes represented by the following formula:

[0019] In the formula, n is a number in the range of 1 to 1000, preferably a number in the range of 50 to 750. m is a number in the range of 3 to 100, more preferably a number in the range of 3 to 20, more preferably a number in the range of 3 to 15. Ａｃ is the vinyl-modified group bonded to the silicon atom described above.

[0020] [Synthesis Method by Transvinylation] Such vinyl-modified organopolysiloxanes have relatively long-chain functional groups as spacers between silicon atoms, and therefore, -R １ -C(=O)-OH (wherein, R １ The vinyl vinyl compound can be obtained by reacting a precursor compound having a carboxylic acid modifying group represented by the formula (wherein R is a divalent organic group having 4 to 20 carbon atoms) with vinyl acetate in the presence of a palladium metal catalyst to cause a transvinylation reaction.

[0021] More specifically, the method for producing a vinyl-modified organopolysiloxane according to the present invention comprises: １ -C(=O)-OH (wherein, R １ is a divalent organic group having 4 to 20 carbon atoms), and ３ ２ SiO) ｎ - (wherein, R ３is an unsubstituted or halogen-substituted alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 22 carbon atoms, or a hydroxyl group, and n is a number in the range of 1 to 1,000), with vinyl acetate in the presence of a palladium metal catalyst.

[0022] The carboxylic acid-modified organopolysiloxane is a precursor material, and the linking group (spacer) between the Si atom and the carboxylic acid-modifying group is the above-mentioned R １ In this production method, once a carboxylic acid-modified silicone raw material to be transvinylated into a vinyl-modified organopolysiloxane is prepared, the vinyl-modified organopolysiloxane can be obtained industrially easily and inexpensively.

[0023] A vinyl carboxylate compound is a raw material for transvinylation of a carboxylic acid-modified group, and is converted into a vinyl-modified group (R Ａｃ ) is obtained. The vinyl carboxylate compound is not particularly limited as long as it is capable of transvinylation, and examples thereof include vinyl acetate, vinyl pivalate, vinyl butyrate, and vinyl propionate. Vinyl acetate is particularly preferred because it is inexpensive and has excellent reactivity. A palladium metal catalyst may be used in combination with a ligand for heavy metals, such as 1,10-phenanthroline.

[0024] The reaction may be carried out in an organic solvent or in a liquid vinyl carboxylate compound such as vinyl acetate. While there are no limitations on the reaction conditions, it is preferable to carry out the transvinylation reaction by heating at room temperature to 100°C while stirring and bubbling N2, thereby converting the carboxylic acid end group into a vinyl ester structure. The reaction time depends on the reaction scale and reaction temperature, but is generally in the range of several hours to several tens of hours.

[0025] [Use as a Starting Material for Radically Polymerizable Polymers or Copolymers] The vinyl-modified organopolysiloxane of the present invention is radically polymerizable, and the resulting radically polymerizable polymers or copolymers are expected to be biodegradable. Such radically polymerizable polymers or copolymers can be obtained by radical polymerization of the vinyl-modified organopolysiloxane of the present invention alone, or of the vinyl-modified organopolysiloxane of the present invention in combination with one or more radically polymerizable monomers, in the presence of a radical initiator.

[0026] The radical initiator may be a conventionally known compound generally used in radical polymerization methods, and specific examples include azo compounds such as 2,2'-azobis(isobutyrate)dimethyl, 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2-methylbutyronitrile), and 2,2'-azobis(2,4-dimethylvaleronitrile); organic peroxides such as benzoyl peroxide, lauroyl peroxide, tert-butyl peroxybenzoate, tert-butylperoxy-2-ethylhexanoate, and tert-hexylperoxy-2-ethylhexanoate; and persulfates such as potassium persulfate, sodium persulfate, and ammonium persulfate. These radical initiators may be used alone or in combination of two or more.

[0027] The amount of radical initiator used is preferably in the range of 0.1 to 5 parts by mass per 100 parts by mass of the total of the radically polymerizable components including the vinyl-modified organopolysiloxane.

[0028] Here, when an oil-soluble azo compound is used, a radically polymerizable polymer or copolymer can be obtained without the need for a solvent. On the other hand, when the radical initiator is a water-soluble persulfate such as potassium persulfate, there is the advantage that addition and reaction are extremely easy when crosslinking reactive silicone emulsion particles obtained by emulsifying a crosslinkable reactive silicone composition by radical polymerization reaction (described below) in water are subjected to a crosslinking reaction in water. Furthermore, when completing the radical polymerization reaction, it is particularly preferable to add aminomethylpropanediol or the like in the range of 0.1 to 5 parts by mass for the purpose of terminating the reaction and neutralizing the solution by adjusting the pH.

[0029] In the polymerization reaction using the above radical initiator, a chain transfer agent can be optionally added. Specific examples of the chain transfer agent include mercapto compounds such as 2-mercaptoethanol, butyl mercaptan, n-dodecyl mercaptan, 3-mercaptopropyltrimethoxysilane, and polydimethylsiloxane having a mercaptopropyl group; and halides such as methylene chloride, chloroform, carbon tetrachloride, butyl bromide, and 3-chloropropyltrimethoxysilane.

[0030] Other radical polymerizable monomers are generally exemplified by acrylic acid ester monomers or methacrylic acid ester monomers having 4 to 13 carbon atoms, and may be acrylic acid esters or methacrylic acid esters having 4 to 10 carbon atoms. Typical examples include methyl (meth)acrylate, ethyl (meth)acrylate, and n-propyl (meth)acrylate.

[0031] On the other hand, polyfunctional vinyl monomers can also be used, and examples thereof include trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, ethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, trimethylolpropane trioxyethyl (meth)acrylate, tris(2-hydroxyethyl)isocyanurate di(meth)acrylate, tris(2-hydroxyethyl)isocyanurate tri(meth)acrylate, and unsaturated group-containing silicone compounds such as styryl group-blocked polydimethylsiloxane.

[0032] However, in the radical polymerizable copolymer according to the present invention, the other radical polymerizable monomers are preferably vinyl acetate and (meth)acrylic-modified polycaprolactone compounds, since the inclusion of these components as raw materials may improve the biodegradability of the resulting radical polymerizable copolymer.

[0033] For example, the radically polymerizable copolymer of the present invention may include vinyl acetate as a starting material, and the structure derived from such a monomer component may improve the biodegradability of the resulting radically polymerizable copolymer, as well as oil absorption and formulation stability.

[0034] For example, the radical polymerizable polymer of the present invention may contain, as a starting material, a (meth)acrylic-modified polycaprolactone compound having the following structural formula (1) in the molecule: (1) The (meth)acrylic-modified polycaprolactone compound may contain two or more modified polycaprolactone structures having the formula (1). The structure derived from such a monomer component may improve the biodegradability of the resulting radical-polymerizable copolymer, and may also improve the feel to the touch and sensation when used.

[0035] In the formula, n represents the number of caprolactone units in the structure {—C(═O)—C ５ H １０—O—}, and is a number in the range of 1 to 5, and may be a number in the range of 1 to 3. Furthermore, Ra is —C(═O)—R １ -CR ２ =CH ２ where R １ is a chemical bond between CH and C(=O) or a divalent organic group having 1 to 20 carbon atoms, and may be a simple bond structure such as "-C(=O)-CH=" or an alkylene group having 1 to 20 carbon atoms represented by CmH2m such as "-C(=O)-CmH2m-CH=" (m is a number in the range of 1 to 20) (note that R １ is a chemical bond between CH and C(=O), m is 0.) Also, R ２ is a hydrogen atom or a methyl group, which provides an acrylic or methacrylic modified group, respectively.

[0036] More specifically, the (meth)acrylic-modified polycaprolactone compound of the present invention may be a compound represented by one or more structural formulas selected from the following structural formulas (1-1) to (1-3), each of which has two, three, or four modified polycaprolactone structures represented by the following structural formula (1):

[0037] Structural formula (1-1): (1-1) Structural formula (1-2): (1-2) Structural formula (1-3): (1-3)

[0038] In each formula, Ra is the same group as defined above. In structural formula (1-1), m and n are each independently a number in the range of 1 to 5, m+n is a number in the range of 2 to 20, and m+n may be a number in the range of 2.5 to 10, or may be a number in the range of 3 to 7. In structural formula (1-2) or (1-3), w, x, y, and z are each independently a number in the range of 1 to 5, x+y+z is a number in the range of 3 to 20, and w+x+y+z is a number in the range of 4 to 20. Furthermore, x+y+z may be a number in the range of 3 to 7, and w+x+y+z may be a number in the range of 4 to 10.

[0039] Such a (meth)acrylic-modified polycaprolactone compound can be obtained by reacting a precursor polycaprolactone compound having a polyol terminal structure with a (meth)acryloyl chloride compound in the presence of a basic catalyst.

[0040] The radically polymerizable polymer or copolymer containing the vinyl-modified organopolysiloxane of the present invention as at least a part of the starting material may be in the form of a gel or particles, and in particular may be in the form of silicone elastomer particles described below.

[0041] [Silicone elastomer particles] The vinyl-modified organopolysiloxane according to the present invention is useful as a starting material for silicone elastomer particles, and can be obtained by radically polymerizing (A) the above-described vinyl-modified organopolysiloxane and (B) one or more radically polymerizable monomers in the presence of (C) a radical initiator.

[0042] The silicone elastomer particles of the present invention are preferably obtained by curing crosslinkable silicone emulsion particles by a crosslinking reaction. Particularly preferably, the silicone elastomer particles of the present invention are defined by their production process, and are silicone elastomer particles obtained by crosslinking crosslinkable silicone emulsion particles in water, the crosslinkable silicone emulsion particles being obtained by emulsifying in water a crosslinkable silicone composition that is crosslinkable by a radical polymerization reaction, and that contains at least (A) the above-mentioned vinyl-modified organopolysiloxane, (B) one or more radically polymerizable monomers, and (C) a radical polymerization initiator.

[0043] From the standpoint of improving biodegradability and improving the feel to the touch, the sensation during use, and the oil absorbency, the silicone elastomer particles of the present invention preferably contain the vinyl-modified organopolysiloxane described above and, as part or all of component (B), one or more radically polymerizable monomers selected from vinyl acetate and (meth)acrylic-modified polycaprolactone compounds.

[0044] Furthermore, silicone elastomer particles obtained through such a manufacturing process may be able to further improve the appearance, spreadability, and feel of the cosmetic, particularly when used as a cosmetic ingredient, and particles obtained by this manufacturing method tend to be more suitable for solving the problems of the present invention. Thus, one of the preferred modes for achieving the technical effects of the present invention can and appropriately be defined by the manufacturing process.

[0045] The cross-linking reactive silicone composition may contain one or more polymerization inhibitors from the standpoint of preventing unintended side reactions. For example, it may contain one or more selected from hindered phenol-based polymerization inhibitors, hydroquinone-based polymerization inhibitors, and catechol-based polymerization inhibitors. The amount used can be selected appropriately, but the total concentration of the polymerization inhibitors relative to the sum of the components (A) to (C) is preferably 50 ppm by mass or less, and more preferably 30 ppm by mass or less.

[0046] The crosslinkable silicone composition may contain components other than those described above, provided that the technical effects of the present invention are not impaired. For example, the crosslinkable silicone composition may contain organic solvents such as aliphatic hydrocarbons such as n-hexane, cyclohexane, and n-heptane; aromatic hydrocarbons such as toluene, xylene, and mesitylene; ethers such as tetrahydrofuran and dipropyl ether; ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; antioxidants such as phenols, quinones, amines, phosphorus compounds, phosphites, sulfur compounds, and thioether compounds; light stabilizers such as triazoles and benzophenones; flame retardants such as phosphate esters, halogen compounds, phosphorus compounds, and antimony compounds; one or more antistatic agents such as cationic surfactants, anionic surfactants, and nonionic surfactants; dyes; pigments.

[0047] The silicone elastomer particles of the present invention may optionally further have (i) a structure in which a part or all of their surfaces are coated with one or more materials selected from organopolysiloxane resins, silica, and other silicone elastomer particles; (ii) a mesoporous structure; (iii) a structure containing an oil agent that is liquid at 40°C; and (iv) a structure crosslinked by silalkylene groups having 2 to 20 carbon atoms, and optional components that impart these structures may be used in combination.

[0048] [Uses of Radically Polymerizable Polymer or Radical Polymerizable Copolymer] The radically polymerizable polymer or radically polymerizable copolymer according to the present invention (including the silicone elastomer particles described above) is useful as a cosmetic raw material, and when incorporated into cosmetic compositions and the like, it is soft and has an even better effect of improving the feel and usability of the cosmetics and the like, and is remarkably easy to handle as a cosmetic raw material, and has excellent storage stability and incorporation stability into systems.

[0049] Similarly, the radically polymerizable polymer or copolymer of the present invention (including the silicone elastomer particles) is also extremely useful as an additive for organic resins. Specifically, the radically polymerizable polymer or copolymer of the present invention has excellent uniform dispersibility in organic resins and, if desired, excellent stress relaxation properties, and is less likely to aggregate even after long-term storage, resulting in significantly excellent handling, workability, and storage stability. Furthermore, components, paint films, or coating films obtained by curing organic resins containing the silicone elastomer particles have improved flexibility (including the softness of the coating layer), durability, and adhesion and conformability to substrates, and are particularly excellent in flexibility and thermal shock resistance, making them extremely useful as high-performance organic resins, paints, or coating agents for electronic materials.

[0050] [As an Eco-Friendly Material] As described above, the radically polymerizable polymer or copolymer of the present invention is expected to have biodegradable properties, unlike conventional non-biodegradable polymer materials, in that in a biodegradable environment, the cross-linked structures formed between silicon atoms are at least partially cleaved, resulting in the generation of non-cross-linked polyorganosiloxanes and resulting in disintegration. Therefore, it is expected that it can be used as an "eco-friendly" cosmetic ingredient or industrial ingredient with low environmental load and environmental risk in accordance with regulations on microplastics, etc., and that it can be promoted as an "eco-friendly" material with biodegradability to consumers and general consumers who are concerned about the impact on the global environment.

[0051] Example 1: Synthesis of vinyl-modified organopolysiloxane No. 1 In a four-necked round-bottom flask equipped with a mechanical stirrer, a thermometer, and an oil bath, 75.2 parts by weight of a carboxylic acid-modified silicone oil (molecular weight: 31649.36) represented by the formula (I) and 24.6 parts by weight of vinyl acetate (Fujifilm Wako, molecular weight: 86.09) were charged. While stirring at 200 rpm, nitrogen (N2) was bubbled through the mixture for 5 minutes, and then, while aerating with N2, 0.1 parts by weight of palladium acetate (catalyst, Fujifilm Wako, molecular weight: 224.5) and 0.1 parts by weight of 1,10-phenanthroline (ligand, Fujifilm Wako, molecular weight: 180.21) were added. After stirring at room temperature, the temperature was raised to 60°C and the reaction was allowed to proceed overnight. After the reaction was complete, １３ C-NMR analysis confirmed the disappearance of the carboxylic acid derived from the raw material, and the remaining vinyl acetate was distilled off under reduced pressure while bubbling with N2. Finally, the mixture was filtered using filter paper with activated carbon added to remove the catalyst. After filtration, a transparent silicone oil was obtained, which was analyzed by H-NMR and １３ The structure was confirmed by C-NMR, and it was confirmed that vinyl-modified organopolysiloxane No. 1 having the vinyl ester structure shown below was produced.

[0052] Example 2: Synthesis of a Gel Composed of a Radical Polymerizable Polymer. 96 parts by weight of vinyl-modified organopolysiloxane No. 1 was placed in a three-necked round-bottom flask equipped with a stirrer, thermometer, and oil bath. N2 was bubbled through the mixture while stirring at 200 rpm. After 5 minutes of bubbling, 4 parts by weight of an oil-soluble azo polymerization initiator, "Product Name V-601" (2,2'-azobis(isobutyrate) dimethyl, Fujifilm Wako Co., Ltd., molecular weight: 230.26), was added. The mixture was heated to 70°C while stirring, and after 3 hours, a gel-like product, a radical homopolymer of vinyl-modified organopolysiloxane No. 1, was formed in the flask.

[0053] [Example 3, Comparative Example 1: Production of Silicone Elastomer Particles] Hereinafter, an example of the production of silicone elastomer particles obtained using the above-mentioned vinyl-modified organopolysiloxane No. 1 and a (meth)acrylic-modified polycaprolactone compound as raw materials will be described in Example 3. Note that Comparative Example 1 is a non-silicone polymer particle obtained using only a (meth)acrylic-modified polycaprolactone compound as a raw material.

[0054] [Example 3] Vinyl-modified organopolysiloxane No. 1 and a compound having the following structural formula: (where m+n=3.7) and a (meth)acrylic-modified polycaprolactone compound represented by the formula (II) were mixed uniformly at room temperature in a mass ratio of 30:70, and vegetable oil (manufactured by AAK) was added in an amount equivalent to 20% of the total composition. This composition was then dispersed in a 25°C aqueous solution consisting of 0.24 parts by mass of GOHSENOL EG-05C and 0.47 parts by mass of GOHSENOL EG-18P in 46 parts by mass of pure water. The resulting mixture was then uniformly emulsified using a colloid mill and diluted with 300 parts by mass of pure water to prepare an emulsion. The mixture was heated in a 1-L flask until the temperature reached 60°C, at which point an aqueous solution of 0.5 g of potassium persulfate (manufactured by Sigma-Aldrich) in 9.5 g of water was added dropwise over 1 minute. This emulsion was then stirred at 100 rpm at 60°C for 3 hours to undergo radical polymerization, producing a uniform aqueous suspension of silicone rubber particles. The aqueous suspension was then filtered and washed with 200 ml of ethanol and 100 ml of acetone. The residue was dried in an oven at 70°C for 3 hours to obtain silicone elastomer particles. The average secondary particle diameter of the resulting silicone elastomer particles was 119 μm.

[0055] [Comparative Example 1] Silicone elastomer particles were obtained in the same manner as in Example 3, except that no polyorganosiloxane was used and 100 parts by mass of the (meth)acrylic-modified polycaprolactone compound used as a raw material in Example 3 was used instead. The average secondary particle diameter of the obtained silicone elastomer particles was 70.0 μm.

[0056] The average primary particle size and average secondary particle size of each of the particles obtained in Example 3 and Comparative Example 1 are summarized in Table 1 below.

[0057] [Cosmetic Formulation Examples] Below are formulation examples of cosmetics of the present invention that can incorporate silicone elastomer particles, one aspect of the present invention. However, the present invention is not limited to these. The silicone elastomer particles of Example 3 and the powder of Comparative Example 1 were applied to the inside of the arm and compared and evaluated by a panel. The silicone elastomer particles of Example 3 were softer and smoother than the powder of Comparative Example 1.

[0058] [Example 4, Comparative Example 5] Panelists compared and evaluated the feel of use of loose powders using silicone elastomer particles with the compositions shown in Table 3. (Feeling evaluation) Eighteen panelists applied samples to the inside of their forearms and evaluated the smoothness according to the criteria in Table 2 below.

[0059] (Preparation Method) 1. Mix Phase A. 2. Mix Phase B. 3. Stir Phase A and Phase B until uniform.

[0060] As shown in Table 3, the loose powder using the silicone elastomer particles of the present invention (Example 3) was evaluated to have relatively good slip properties, unlike the loose powder using other particles (Comparative Example 1).

Claims

1. In the molecule, -R bonded to the silicon atom １ -C(=O)-O-CH=CHR ２ (In the formula, R １ is a divalent organic group having 4 to 20 carbon atoms, and R ２ is a hydrogen atom or a methyl group) A vinyl modified group (R Ａｃ ) and -(R ３ ２ SiO) ｎ - (In the formula, R ３ is an unsubstituted or halogen-substituted alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 22 carbon atoms, or a hydroxyl group, and n is a number ranging from 1 to 1000. A vinyl-modified organopolysiloxane having a polyorganosiloxane structure represented by the formula:

2. A vinyl-modified group (R Ａｃ ) in which R １ is an alkylene group having 4 to 20 carbon atoms, and there are three or more vinyl-modified groups (R Ａｃ 2. The vinyl-modified organopolysiloxane of claim 1, wherein

3. The following structural formula: 【Chemistry 1】 (wherein n is a number ranging from 1 to 1000, m is a number ranging from 3 to 100, and R Ａｃ is the vinyl-modified group bonded to the silicon atom described above. The vinyl-modified organopolysiloxane according to claim 1, wherein the vinyl-modified organopolysiloxane is represented by the formula:

4. In the molecule, -R bonded to the silicon atom １ -C(=O)-OH (wherein, R １ is a divalent organic group having 4 to 20 carbon atoms), and -(R ３ ２ SiO) ｎ - (In the formula, R ３ is an unsubstituted or halogen-substituted alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 22 carbon atoms, or a hydroxyl group, and n is a number ranging from 1 to 1000. The method for producing the vinyl-modified organopolysiloxane according to any one of claims 1 to 3, comprising a step of subjecting a carboxylic acid-modified organopolysiloxane having a polyorganosiloxane structure represented by the formula (I) to a transvinylation reaction with a vinyl carboxylate compound in the presence of a palladium metal catalyst.

5. A radically polymerizable polymer or copolymer, comprising the vinyl-modified organopolysiloxane according to any one of claims 1 to 3 as at least a part of the starting materials.

6. A gel-like or particulate material comprising the radically polymerizable polymer or copolymer of claim 5.

7. Silicone elastomer particles, comprising the vinyl-modified organopolysiloxane according to any one of claims 1 to 3 as at least a part of the starting material.

8. (A) the vinyl-modified organopolysiloxane according to any one of claims 1 to 3; (B) one or more radically polymerizable monomers; (C) Radical initiator 8. The silicone elastomer particles according to claim 7, which are obtained by emulsifying in water a crosslinkable silicone composition prepared by radical polymerization, the composition comprising at least the following:

9. 8. The silicone elastomer particles according to claim 7, wherein the component (B) contains one or more radically polymerizable monomers selected from vinyl acetate and (meth)acrylic-modified polycaprolactone compounds and is biodegradable.

10. A cosmetic raw material comprising the radically polymerizable polymer or copolymer according to claim 5 .

11. A cosmetic composition comprising the radically polymerizable polymer or copolymer according to claim 5 .

12. An organic resin additive comprising the radically polymerizable polymer or copolymer of claim 5 .

13. An organic resin comprising the radically polymerizable polymer or copolymer according to claim 5 .

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