Copolymer, elastomer spherical particles, dispersion liquid of elastomer spherical particles, and method for producing same

Abstract

Provided are: a copolymer having a polyester structure and a polyether structure, which have high degradation properties by external stimulation such as light; it is preferable that: a polyester-polyether copolymer having at least two radically polymerizable unsaturated groups in one molecule; elastomer spherical particles having structural units derived from the copolymer; and a method for producing the same. The copolymer has a polyester structure and a polyether structure; the elastomer spherical particles have a volume average particle diameter of 0.5-200 [mu] m, and contain a polymer containing a structural unit derived from a copolymer having a polyester structure and a polyether structure.

Description

Technical Field

[0001] The present invention relates to elastic spherical particles, a dispersion of elastic spherical particles, and a method for producing the same. Background Art

[0002] Conventionally, as raw material rubbers for rubber products, there are, for example,

[0003] [1] Polymers whose repeating units consist only of conjugated diene units, represented by butadiene rubber, isoprene rubber, chloroprene rubber, and natural rubber.

[0004] [2] A polymer having a conjugated diene unit and an aromatic vinyl unit as essential repeating units, represented by styrene-butadiene copolymer rubber, styrene-isoprene copolymer rubber, and styrene-isoprene-butadiene copolymer rubber,

[0005] [3] A polymer represented by acrylonitrile-butadiene copolymer rubber, wherein the repeating units are essentially conjugated diene units and α,β-unsaturated nitrile units,

[0006] [4] A polymer represented by acrylic rubber, wherein the repeating unit is an essential unit of acrylic acid,

[0007] [5] A polymer represented by ethylene-propylene rubber, the repeating units of which contain ethylene, an α-olefin having 3 to 12 carbon atoms, and, if necessary, a non-conjugated polyene,

[0008] [6] Polymers such as silicone rubber whose repeating units contain dimethylsiloxane units are widely used.

[0009] Elastomer (rubber) spherical particles, particularly elastomer (rubber) spherical particles containing an organic skeleton, are used mainly for electronic material applications including electronic devices in order to improve various properties such as impact resistance, thermal shock resistance, and adhesion.

[0010] On the other hand, silicone rubber spherical particles and powders have been proposed for use in a wide range of industrial fields.

[0011] For example, it is disclosed that the compound is added to synthetic resin materials (Patent Documents 1 and 2), synthetic rubber materials (Patent Document 3), cosmetics (Patent Documents 4 to 7), and the like.

[0012] Organic silicone rubber spherical particles are used as a stress reducing agent for organic resins such as epoxy resins, for example, by taking advantage of their "flexibility". That is, due to the difference in thermal expansion coefficients between electronic components and organic resins such as epoxy resins, stress may cause cracks and ruptures to occur on the resins, and therefore, the addition of organic silicone rubber spherical particles can prevent the occurrence of such cracks and ruptures.

[0013] Specifically, epoxy resins containing spherical particles of a cured polymer containing linear organopolysiloxane blocks (Patent Document 8) and epoxy resins containing spherical particles of silicone rubber coated with polyorganosilsesquioxane (Patent Document 9) have been proposed.

[0014] In addition, there is disclosed a method for producing silicone-containing rubber spherical particles by copolymerizing (meth)acrylate and diorganopolysiloxane having an organic group containing a radical polymerizable functional group at one end in an emulsified system (Patent Document 10).

[0015] It should be noted that the spherical particles are used for the purpose of imparting lubricity to the thermoplastic resin.

[0016] Furthermore, organic crosslinked rubber spherical particles formed by crosslinking a liquid composition composed of an organic compound having an aliphatic saturated bond and a silicon-containing organic compound having hydrogen atoms bonded to silicon atoms through a hydrosilylation reaction are described (Patent Document 11), and it has been proposed that the particles have excellent dispersibility and handling properties in various components such as resins, coatings and rubbers.

[0017] In addition, silicone rubber spherical particles are used in a wide range of cosmetics and cosmetic materials, such as foundation and foundation cream, basic cosmetics such as cream and lotion, and sunscreen cosmetics, in order to give cosmetics a soft and smooth feel, create a natural finish by scattering light, and make pores and wrinkles less visible.

[0018] For example, cosmetics containing polymethylsilsesquioxane particles and powders (Patent Document 12), color cosmetics containing spherical silicone rubber particles and powders (Patent Document 13), and cosmetics containing composite silicone powders in which silicone rubber spherical particles are coated with silicone silsesquioxane resins (Patent Document 14) have been proposed. These silicone rubber spherical particles or composite particles in which polysilsesquioxane resins are coated with silicone rubber spherical particles can provide the cosmetics with a soft touch in addition to the above-mentioned feeling of use.

[0019] Prior art literature

[0020] Patent Literature

[0021] Patent Document 1: Japanese Patent Publication No. 63-12489

[0022] Patent Document 2: Japanese Patent Publication No. 6-55805

[0023] Patent Document 3: Japanese Patent Application Laid-Open No. 2-102263

[0024] Patent Document 4: Japanese Patent Application Laid-Open No. 8-12546

[0025] Patent Document 5: Japanese Patent Application Laid-Open No. 8-12545

[0026] Patent Document 6: Japanese Patent Publication No. 4-17162

[0027] Patent Document 7: Japanese Patent Publication No. 4-66446

[0028] Patent Document 8: Japanese Patent Application Laid-Open No. 58-219218

[0029] Patent Document 9: Japanese Patent Application Laid-Open No. 8-85753

[0030] Patent Document 10: Japanese Patent Application Laid-Open No. 10-182987

[0031] Patent Document 11: Japanese Patent Application Publication No. 2001-40214

[0032] Patent Document 12: Japanese Patent Application Laid-Open No. 63-297313

[0033] Patent Document 13: Japanese Patent Application Laid-Open No. 8-12524

[0034] Patent Document 14: Japanese Patent Application Laid-Open No. 9-20631 Summary of the invention

[0035] Problem that the invention aims to solve

[0036] However, the above-mentioned spherical silicone rubber particles mixed with resins or cosmetics do not have a degradable skeleton or unit in the particle structure, so when released and flowed into the natural environment such as soil, inland waters, seawater, and the ocean, they cannot be degraded and are expected to continue to remain in the environment. In addition, since the particle size of these particles is very small, it is also very difficult to recycle them, and the current situation of flowing into the ocean cannot be avoided.

[0037] In addition, since plastics / microplastics that flow into the ocean have the characteristics of absorbing harmful substances and pathogens in the environment, there are concerns that they will have adverse effects on the ecosystem. Therefore, restrictions on microplastics have also been initiated.

[0038] Considering this background, silicone rubber spherical particles or elastomer (rubber) spherical particles that degrade in the environment after use and do not remain as particles (solid matter) are sought. In order to environmentally degrade elastomer (rubber) spherical particles, it is necessary to degrade and cut the cross-linked structure of the particles in the environment, but in the case of silicone rubber spherical particles, they are not degradable in structure.

[0039] In view of the above problems, the present invention aims to provide a spherical elastomer (rubber) particle, a dispersion of the spherical elastomer particle and a method for producing the same. The spherical elastomer (rubber) particle has as a structural unit a copolymer having high degradability under external stimuli such as light, heat, acid and alkali in natural environments including soil, inland waters, oceans and seawater.

[0040] Another object of the present invention is to provide a copolymer which is suitable for the production of the above-mentioned elastomer (rubber) spherical particles and has high decomposability by external stimulation.

[0041] Methods used to solve problems

[0042] The present inventors have repeatedly conducted intensive studies to achieve the above-mentioned purpose and have found that copolymers having specific polyester structures and polyether structures, elastomeric spherical particles containing polymers containing structural units derived from the copolymers, and dispersions thereof can solve the above-mentioned problems, thereby completing the present invention.

[0043] Therefore, the present invention provides the following copolymers, elastomeric spherical particles, dispersions of elastomeric spherical particles, and methods for producing the same. [1].

[0045] A polyester-polyether copolymer has at least two free radical polymerizable unsaturated groups in one molecule and is represented by the following general formula (1) or (2).

[0046] [Chemical formula 1]

[0047]

[0048] (In the general formula (1), R 1 Each independently represents a divalent hydrocarbon group having 1 to 10 carbon atoms, and R 2 Each independently represents an organic group containing a free radical polymerizable functional group represented by the following general formula (3a), general formula (3b) or general formula (3c), k is independently a number of 1≤k≤10, l is a number of 1≤l≤1000, m is a number of 1≤m≤1000, and n is independently a number of 1≤n≤100,

[0049] In the general formula (2), R 3Each independently represents a divalent hydrocarbon group having 1 to 10 carbon atoms, and R 4 Each independently represents an organic group containing a free radical polymerizable functional group represented by the following general formula (4a) or general formula (4b), p is independently a number of 1≤p≤10, l is a number of 1≤l≤1000, m is a number of 1≤m≤1000, and q is independently a number of 1≤q≤100.)

[0050] [Chemical formula 2]

[0051]

[0052] (In the general formula (3a), the general formula (3b), the general formula (3c), the general formula (4a) and the general formula (4b), R 5 Each independently represents a divalent hydrocarbon group having 1 to 8 carbon atoms, and R 6 They represent a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms. [2].

[0054] The polyester-polyether copolymer described in [1] is represented by the following general formula (5):

[0055] [Chemical formula 3]

[0056]

[0057] (In general formula (5), R 1 Each independently represents a divalent hydrocarbon group having 1 to 10 carbon atoms, and R 2 Each independently represents an organic group containing a radical polymerizable functional group represented by the following general formula (3a), general formula (3b) or general formula (3c), l is a number of 1≤l≤1000, m is a number of 1≤m≤1000, and r is a number of 1≤r≤100,

[0058] [Chemical formula 4]

[0059]

[0060] In the general formula (3a), the general formula (3b) and the general formula (3c), R 5 Each independently represents a divalent hydrocarbon group having 1 to 8 carbon atoms, and R 6 They represent a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms. [3].

[0062] The invention discloses spherical elastic particles, which have a volume average particle diameter of 0.5 to 200 μm and contain a polymer containing a structural unit derived from a copolymer having a polyester structure and a polyether structure. [4].

[0064] The spherical elastomer particles according to [3], wherein the copolymer is a polyester-polyether copolymer having at least two free radical polymerizable unsaturated groups in one molecule. [5].

[0066] The spherical elastic particles as described in [4], wherein the copolymer is a polyester-polyether copolymer represented by the following general formula (1) or general formula (2):

[0067] [Chemical formula 5]

[0068]

[0069] (In the general formula (1), R 1 Each independently represents a divalent hydrocarbon group having 1 to 10 carbon atoms, and R 2 Each independently represents an organic group containing a free radical polymerizable functional group represented by the following general formula (3a), general formula (3b) or general formula (3c), k is independently a number of 1≤k≤10, l is a number of 1≤l≤1000, m is a number of 1≤m≤1000, and n is independently a number of 1≤n≤100,

[0070] In the general formula (2), R 3 Each independently represents a divalent hydrocarbon group having 1 to 10 carbon atoms, and R 4 Each independently represents an organic group containing a free radical polymerizable functional group represented by the following general formula (4a) or general formula (4b), p is independently a number of 1≤p≤10, l is a number of 1≤l≤1000, m is a number of 1≤m≤1000, and q is independently a number of 1≤q≤100.)

[0071] [Chemical formula 6]

[0072]

[0073] (In the general formula (3a), general formula (3b), general formula (3c), (4a) and general formula (4b), R 5 Each independently represents a divalent hydrocarbon group having 1 to 8 carbon atoms, and R 6 They represent a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms. [6].

[0075] The spherical elastic particles as described in [5], wherein the copolymer is a polyester-polyether copolymer represented by the following general formula (5):

[0076] [Chemical formula 7]

[0077]

[0078] (In general formula (5), R1 Each independently represents a divalent hydrocarbon group having 1 to 10 carbon atoms, and R 2 Each independently represents an organic group containing a free radical polymerizable functional group represented by the following general formula (3a), general formula (3b) or general formula (3c), l is a number of 1≤l≤1000, m is a number of 1≤m≤1000, and r is a number of 1≤r≤100.)

[0079] [Chemical formula 8]

[0080]

[0081] (In general formula (3a), general formula (3b) and general formula (3c), R 5 Each independently represents a divalent hydrocarbon group having 1 to 8 carbon atoms, and R 6 They represent a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms. [7].

[0083] A dispersion of spherical particles of an elastomer,

[0084] The spherical elastic particles described in any one of [3] to [6] are dispersed in at least one dispersion medium selected from silicone oil, hydrocarbon oil, higher fatty acid, ester oil, liquid fat and water. [8].

[0086] The method for producing elastic spherical particles according to any one of [3] to [6], comprising the following steps (i) to (iii):

[0087] (i)

[0088] It is stirred and emulsified

[0089] (A) a copolymer having a polymerizable group and having a polyester structure and a polyether structure,

[0090] (B) an oil phase component or an aqueous phase component that is insoluble in the component (A),

[0091] (C) a surfactant, and

[0092] (D) A step of preparing an O / O type emulsion or an O / W type emulsion by adding a polymerization initiator

[0093] (ii)

[0094] This is a step of obtaining a dispersion of elastic spherical particles by polymerizing the component (A) in the O / O type emulsion or O / W type emulsion obtained in the step (i).

[0095] (iii)

[0096] This is a step of obtaining elastic spherical particles by washing and drying the (B) component as a continuous phase from the dispersion of the elastic spherical particles obtained in the step (ii). [9].

[0098] The manufacturing method as described in [8], wherein

[0099] The step (i) is to stir and emulsify

[0100] (A) a copolymer having a polymerizable group and having a polyester structure and a polyether structure,

[0101] (B) an oil phase component that is insoluble in the component (A),

[0102] (C) a surfactant, and

[0103] (D) A step of obtaining an O / O type emulsion by adding a polymerization initiator.

[0104] Effects of the Invention

[0105] The copolymer of the present invention has a polyester structure with a degradable functional group (unit), and the cross-linked structure is cut in the presence of water, so it has degradability. In particular, the copolymer having a poly-ε-caprolactone structure as a microorganism recognition skeleton in the polyester structure can also be expected to have environmental degradability, so it can be used in various industrial fields, and in particular, in addition to manufacturing the elastic spherical particles of the present invention, it can also be expected to replace various organic resins / plastics or be used as a new resin / plastic material.

[0106] In addition, the spherical elastic particles of the present invention have a polyester structure as a degradable functional group (unit) in the particles, and the cross-linked structure is cut in the presence of water, so they have degradability. In particular, particles having a poly-ε-caprolactone structure as a microbial recognition skeleton as a polyester structure in the particles can also be expected to have environmental degradability of the spherical elastic particles.

[0107] Therefore, the elastic spherical particles of the present invention are degradable particles and can be expected to be a material for reducing environmental load. BRIEF DESCRIPTION OF THE DRAWINGS

[0108] [ Figure 1 ] is an electron microscope photograph of the elastomer spherical particles obtained in Example 1.

[0109] [Fig. 2] is an electron microscope photograph of the elastomer spherical particles obtained in Example 5, Figure 2A For photos magnified 200 times, Figure 2B The photo is magnified 1000 times. DETAILED DESCRIPTION

[0110] Hereinafter, the present invention will be described in detail.

[0111] [Copolymer]

[0112] The copolymer of the present invention is a copolymer represented by the following general formula (1) or (2), and is a polyester-polyether copolymer having at least two free radical polymerizable unsaturated groups in one molecule.

[0113] [Chemical formula 9]

[0114]

[0115] In the general formula (1), R 1 Each independently represents a divalent hydrocarbon group having 1 to 10 carbon atoms, and R 2 Each independently represents an organic group containing a free radical polymerizable functional group represented by the following general formula (3a), general formula (3b) or general formula (3c), k is independently a number of 1≤k≤10, l is a number of 1≤l≤1000, m is a number of 1≤m≤1000, and n is independently a number of 1≤n≤100.

[0116] In the general formula (2), R 3 Each independently represents a divalent hydrocarbon group having 1 to 10 carbon atoms, and R 4 Each independently represents an organic group containing a free radical polymerizable functional group represented by the following general formula (4a) or general formula (4b), p is independently a number of 1≤p≤10, l is a number of 1≤l≤1000, m is a number of 1≤m≤1000, and q is independently a number of 1≤q≤100.

[0117] [Chemical formula 10]

[0118]

[0119] In the general formula (3a), the general formula (3b), the general formula (3c), the general formula (4a) and the general formula (4b), R 5 Each independently represents a divalent hydrocarbon group having 1 to 8 carbon atoms, and R 6 Respectively represent a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms

[0120] As R 1 , examples thereof include alkylene groups such as methylene, ethylene, propylene, trimethylene, tetramethylene, pentamethylene, hexamethylene, heptamethylene and octamethylene, and methylene, ethylene, trimethylene and tetramethylene are preferred.

[0121] As R 3, examples thereof include alkylene groups such as methylene, ethylene, propylene, trimethylene, tetramethylene, pentamethylene, hexamethylene, heptamethylene and octamethylene, and methylene, ethylene, trimethylene and tetramethylene are preferred.

[0122] R 2 represents an organic group containing a radical polymerizable functional group represented by the general formula (3a), the general formula (3b) or the general formula (3c), R 4 It represents an organic group having a radical polymerizable functional group represented by the general formula (4a) or the general formula (4b).

[0123] In the general formula (3b), the general formula (3c), the general formula (4a) and the general formula (4b), R 5 , examples thereof include alkylene groups such as methylene, ethylene, propylene, trimethylene, tetramethylene, pentamethylene, hexamethylene, heptamethylene and octamethylene, and methylene, ethylene, trimethylene and tetramethylene are preferred.

[0124] In the general formula (3a), the general formula (3b), the general formula (3c), the general formula (4a) and the general formula (4b), as R 6 The hydrocarbon group having 1 to 3 carbon atoms represented by is exemplified by an alkyl group having 1 to 3 carbon atoms such as a methyl group, an ethyl group, and a propyl group. 6 , preferably a hydrogen atom or a methyl group.

[0125] The organic groups containing free radical polymerizable functional groups represented by these general formulas (3a), (3b), (3c), (4a) and (4b) are residues derived from polymerizable monomers. Specifically, polymerizable monomers include (meth)acrylates containing hydroxyl groups and (meth)acrylates containing isocyanate groups.

[0126] Examples of the (meth)acrylate containing a hydroxyl group include hydroxyalkyl esters of (meth)acrylic acid having 2 to 8 carbon atoms such as hydroxyethyl (meth)acrylate and hydroxypropyl (meth)acrylate; and carboxyl (meth)acrylates such as carboxyethyl acrylate, (meth)acryloyloxyethyl succinate and (meth)acryloyloxyethyl phthalate.

[0127] As an acrylate containing an isocyanate group, isocyanate ethyl (meth)acrylate, isocyanate propyl (meth)acrylate, isocyanate butyl (meth)acrylate, isocyanate hexyl (meth)acrylate, etc. are mentioned, for example.

[0128] In the general formula (1), k is independently a number of 1≤k≤10, preferably a number of 1≤k≤6.

[0129] In the general formula (2), p is independently a number of 1≤p≤10, preferably a number of 1≤p≤6.

[0130] In addition, n in the general formula (1) is independently a number of 1≤n≤100, preferably a number of 1≤n≤30, and more preferably a number of 2≤n≤10.

[0131] In the general formula (2), q is independently a number of 1≤q≤100, preferably a number of 1≤q≤30, and more preferably a number of 2≤q≤10.

[0132] When the values ​​of n and q are too large, the crystallinity increases due to the intramolecular / intermolecular interactions of the polymer at the ester bond site, which may affect the handling properties in the emulsification step described later.

[0133] In the general formula (1), l is a number of 1≤l≤1000, preferably a number of 2≤l≤100.

[0134] In the general formula (1), m is a number of 1≤m≤1000, preferably a number of 10≤m≤500.

[0135] In the general formula (2), l is a number of 1≤l≤1000, preferably a number of 2≤l≤100.

[0136] In the general formula (2), m is a number of 1≤m≤1000, preferably a number of 10≤m≤500.

[0137] From the viewpoint of the handleability of raw materials and the simplicity of production, the copolymer of the present invention is preferably a copolymer represented by the following general formula (5).

[0138] [Chemical formula 11]

[0139]

[0140] In the general formula (5), R 1 Each independently represents a divalent hydrocarbon group having 1 to 10 carbon atoms, and R 2 Each independently represents an organic group containing a free radical polymerizable functional group represented by the following general formula (3a), general formula (3b) or general formula (3c), l is a number of 1≤l≤1000, m is a number of 1≤m≤1000, and r is a number of 1≤r≤100.

[0141] [Chemical formula 12]

[0142]

[0143] In the general formula (3a), the general formula (3b) and the general formula (3c), R 5Each independently represents a divalent hydrocarbon group having 1 to 8 carbon atoms, and R 6 Each represents a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms.

[0144] The copolymer of the present invention can be produced, for example, by the method described below.

[0145] [Elastomer spherical particles]

[0146] The spherical elastomer particles of the present invention are spherical elastomer particles comprising a polymer containing a structural unit derived from a copolymer having a polyester structure and a polyether structure.

[0147] The shape of the elastomeric spherical particles of the present invention is preferably spherical. The "spherical" in the present invention does not only mean that the particle shape is a sphere, but also includes the value of the average aspect ratio (length of the longest axis / length of the shortest axis), which is usually in the range of 1 to 4, preferably in the range of 1 to 2, more preferably in the range of 1 to 1.6, and further preferably in the range of 1 to 1.4. A deformed ellipsoid. As described later, in the case of manufacturing by a method in which a copolymer having a polyester structure and a polyether structure is emulsified and dispersed into a continuous phase using a surfactant or the like and then cross-linked, the shape of the obtained particles is spherical. The shape of the elastomeric spherical particles can be confirmed by observation using, for example, an optical microscope or an electron microscope, and the aspect ratio is a value calculated as the average value by measuring the lengths of the longest axis and the shortest axis of 50 particles from the microscope photograph.

[0148] The volume average particle size of the elastic spherical particles in the present invention is in the range of 0.5 to 200 μm, more preferably in the range of 1 to 100 μm. When the volume average particle size of the elastic spherical particles is higher than the above upper limit, the smoothness of the particles is sometimes reduced, a rough feeling is generated, and the light diffusion characteristics are also reduced. In addition, when the volume average particle size of the elastic spherical particles is less than the above lower limit, the fluidity of the particles is reduced, the cohesion becomes high, and the smoothness and light diffusion characteristics cannot be fully imparted, which is not preferred.

[0149] The volume average particle size of the elastic spherical particles of the present invention is a value measured by the following measurement method. First, before measuring the volume average particle size, the particle sizes of 50 particles are randomly measured from the microscope photograph of the elastic spherical particles, and it is determined whether the average value is 1 μm or more or less than 1 μm. Using a dispersion obtained by redispersing the elastic spherical particles in water using various surfactants, if the result is 1 μm or more, the volume average particle size is a value measured by the resistance method, and if the result is less than 1 μm, the volume average particle size is a value measured by the laser diffraction / scattering method.

[0150] The rubber (elastic body) of the spherical particle component of the elastic body is preferably a rubber that does not produce stickiness and greasiness. The rubber hardness is preferably in the range of 5 to 90, more preferably in the range of 10 to 80, as measured by a type A durometer in accordance with JIS K6253. In addition, the rubber hardness is preferably in the range of 5 to 90, more preferably in the range of 20 to 85, and further preferably in the range of 40 to 85, as measured by an ASKER rubber durometer type C in accordance with the Standard Standards of the Japanese Rubber Society (SRIS).

[0151] When the rubber hardness is less than 5, the cohesiveness may be increased and the dispersibility may be reduced. On the other hand, when the rubber hardness is more than 90, the soft touch may be reduced, which is not preferred.

[0152] The spherical elastic particles of the present invention are more preferably spherical elastic particles formed by polymerizing a polyester-polyether copolymer having at least two free-radically polymerizable unsaturated groups in one molecule.

[0153] The polyester-polyether copolymer having at least two free-radically polymerizable unsaturated groups in one molecule is preferably a copolymer represented by the following general formula (1) or (2).

[0154] [Chemical formula 13]

[0155]

[0156] (In the general formula (1), R 1 Each independently represents a divalent hydrocarbon group having 1 to 10 carbon atoms, and R 2 Each independently represents an organic group containing a free radical polymerizable functional group represented by the following general formula (3a), general formula (3b) or general formula (3c), k is independently a number of 1≤k≤10, l is a number of 1≤l≤1000, m is a number of 1≤m≤1000, and n is independently a number of 1≤n≤100.

[0157] In the general formula (2), R 3 Each independently represents a divalent hydrocarbon group having 1 to 10 carbon atoms, and R 4 Each independently represents an organic group containing a free radical polymerizable functional group represented by the following general formula (4a) or general formula (4b), p is independently a number of 1≤p≤10, l is a number of 1≤l≤1000, m is a number of 1≤m≤1000, and q is independently a number of 1≤q≤100.)

[0158] [Chemical formula 14]

[0159]

[0160] (In the general formula (3a), the general formula (3b), the general formula (3c), the general formula (4a) and the general formula (4b), R 5 Each independently represents a divalent hydrocarbon group having 1 to 8 carbon atoms, and R 6 They represent a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms.

[0161] As R 1 , examples thereof include alkylene groups such as methylene, ethylene, propylene, trimethylene, tetramethylene, pentamethylene, hexamethylene, heptamethylene and octamethylene, and methylene, ethylene, trimethylene and tetramethylene are preferred.

[0162] As R 3 , examples thereof include alkylene groups such as methylene, ethylene, propylene, trimethylene, tetramethylene, pentamethylene, hexamethylene, heptamethylene and octamethylene, and methylene, ethylene, trimethylene and tetramethylene are preferred.

[0163] R 2 represents an organic group containing a radical polymerizable functional group represented by the general formula (3a), the general formula (3b) or the general formula (3c), R 4 It represents an organic group having a radical polymerizable functional group represented by the general formula (4a) or the general formula (4b).

[0164] In the general formula (3b), the general formula (3c), the general formula (4a) and the general formula (4b), R 5 , examples thereof include alkylene groups such as methylene, ethylene, propylene, trimethylene, tetramethylene, pentamethylene, hexamethylene, heptamethylene and octamethylene; preferably, methylene, ethylene, trimethylene and tetramethylene are used.

[0165] In the general formula (3a), the general formula (3b), the general formula (3c), the general formula (4a) and the general formula (4b), as R 6 The hydrocarbon group having 1 to 3 carbon atoms represented by is exemplified by an alkyl group having 1 to 3 carbon atoms such as a methyl group, an ethyl group, and a propyl group. 6 , preferably a hydrogen atom or a methyl group.

[0166] The organic groups containing free radical polymerizable functional groups represented by these general formulas (3a), (3b), (3c), (4a) and (4b) are residues derived from polymerizable monomers. Specifically, the polymerizable monomers include (meth)acrylates containing hydroxyl groups and (meth)acrylates containing isocyanate groups.

[0167] Examples of the (meth)acrylate containing a hydroxyl group include hydroxyalkyl esters of (meth)acrylic acid having 2 to 8 carbon atoms, such as hydroxyethyl (meth)acrylate and hydroxypropyl (meth)acrylate; and carboxyl (meth)acrylates such as carboxyethyl acrylate, (meth)acryloyloxyethyl succinate and (meth)acryloyloxyethyl phthalate.

[0168] As an acrylate containing an isocyanate group, isocyanate ethyl (meth)acrylate, isocyanate propyl (meth)acrylate, isocyanate butyl (meth)acrylate, isocyanate hexyl (meth)acrylate, etc. are mentioned, for example.

[0169] The polyester structure of the polyester-polyether copolymer having at least two radically polymerizable unsaturated groups in one molecule is preferably an aliphatic polyester from the viewpoint of high degradability.

[0170] Examples of the aliphatic polyester include poly-ε-caprolactone, poly-β-propiolactone, γ-butyrolactone, polylactic acid, polyhydroxybutyrate, polyglycolic acid, polyethylene adipate, polyhydroxybutyric acid, polyethylene succinate, and polybutylene succinate. From the viewpoint of degradability and ease of handling, a poly-ε-caprolactone structure is particularly preferred.

[0171] In the general formula (1), k is independently a number of 1≤k≤10, preferably a number of 1≤k≤6.

[0172] In the general formula (2), p is independently a number of 1≤p≤10, preferably a number of 1≤p≤6.

[0173] In addition, n in the general formula (1) is independently a number of 1≤n≤100, preferably a number of 1≤n≤30, and more preferably a number of 2≤n≤10.

[0174] In the general formula (2), q is independently a number of 1≤q≤100, preferably a number of 1≤q≤30, and more preferably a number of 2≤q≤10.

[0175] When the values ​​of n and q are too large, the crystallinity increases due to the intramolecular / intermolecular interactions of the polymer at the ester bond site, which may affect the handleability in the emulsification step described later.

[0176] In the general formula (1), l is a number of 1≤l≤1000, preferably a number of 2≤l≤100.

[0177] In the general formula (1), m is a number of 1≤m≤1000, preferably a number of 10≤m≤500.

[0178] In the general formula (2), l is a number of 1≤l≤1000, preferably a number of 2≤l≤100.

[0179] In the general formula (2), m is a number of 1≤m≤1000, preferably a number of 10≤m≤500.

[0180] The polyester-polyether copolymer having at least two radically polymerizable unsaturated groups in one molecule is preferably a copolymer represented by the following general formula (5) or (6) from the viewpoint of the handleability of the raw materials and the simplicity of production.

[0181] [Chemical formula 15]

[0182]

[0183] (In general formula (5), R 1 Each independently represents a divalent hydrocarbon group having 1 to 10 carbon atoms, and R 2 Each independently represents an organic group containing a free radical polymerizable functional group represented by the general formula (3a), (3b) or (3c), l is a number of 1≤l≤1000, m is a number of 1≤m≤1000, and r is a number of 1≤r≤100.)

[0184] (In general formula (6), R 3 Each independently represents a divalent hydrocarbon group having 1 to 10 carbon atoms, and R 4 Each independently represents an organic group containing a free radical polymerizable functional group represented by the general formula (4a) or the general formula (4b), l is a number of 1≤l≤1000, m is a number of 1≤m≤1000, and s is a number of 1≤s≤100.)

[0185] [Method for producing polyester-polyether copolymer]

[0186] As a method for producing a polyester-polyether copolymer, for example, there can be mentioned a method for producing a poly-ε-caprolactone-modified polyether obtained by ring-opening polymerization of cyclic-ε-caprolactone using various polyethers containing active hydrogen such as polyether, carboxyl-modified polyether and amino-modified polyether as starting materials, by introducing a polymerizable monomer having an unsaturated group capable of free radical polymerization into the copolymer via an ester bond, an ether bond, a urethane bond, an amide bond or the like.

[0187] In addition, from the viewpoint of reactivity, the terminal structure of various polyethers is preferably a structure in which a reactive functional group is bonded to a primary carbon atom.

[0188] As the reaction conditions in the above-mentioned production method, for example, the following reaction conditions can be mentioned, but the reaction conditions are not limited to these reaction conditions.

[0189] For example, 3 to 4 equivalents (functional group equivalents) of ε-caprolactone are added to 1.0 equivalent of a polyether or a polyether containing active hydrogen such as a carboxyl-modified polyether, and the mixture is reacted at 120°C for 6 hours in the presence of a conventionally known ring-opening polymerization catalyst to obtain a poly-ε-caprolactone-modified polyether.

[0190] Next, 1.0 to 1.25 equivalents (1.0 to 1.25 moles) of acryloyl chloride relative to the functional group is added to 1.0 mole of the hydroxyl group of the poly-ε-caprolactone modified polyether obtained above, and a reaction catalyst is added as needed, and the mixture is reacted at 40 to 100° C. for more than 4 hours. After the reaction, the product (crude product) is filtered, washed with water, and / or subjected to an adsorption process to remove byproducts, and finally the solvent is distilled off to obtain a poly-ε-caprolactone acrylic acid-modified polyether (polyester-polyether copolymer).

[0191] When a polyether is used as a starting material, the polyester-polyether copolymer may be, for example, a polyester-polyether copolymer represented by the general formula (7a) or the general formula (7b) (only one terminal is described because of the symmetrical structure).

[0192] [Chemical formula 16]

[0193]

[0194] In the general formula (7a) and the general formula (7b), R 5 is a divalent hydrocarbon group having 1 to 8 carbon atoms, R 6 It is a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms.

[0195] l, m and r are 1≤l≤1000, 1≤m≤1000, 1≤r≤30, respectively, and preferably 2≤l≤100, 10≤m≤500, 2≤r≤10, respectively.

[0196] When a carboxyl-modified polyether is used as a starting material, the polyester-polyether copolymer may be, for example, a polyester-polyether copolymer represented by the general formula (8a) or the general formula (8b) (only one terminal is described because of the symmetrical structure).

[0197] [Chemical formula 17]

[0198]

[0199] In formula (8a) and formula (8b), R 5 is a divalent hydrocarbon group having 1 to 8 carbon atoms, R 6 It is a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms.

[0200] In addition, l, m, s and t are 1≤l≤1000, 1≤m≤1000, 1≤s≤30, 0≤t≤10, respectively, and preferably 2≤l≤100, 10≤m≤500, 2≤s≤10, 1≤t≤10, respectively.

[0201] When an amino-modified polyether is used as a starting material, the polyester-polyether copolymer may be, for example, a polyester-polyether copolymer represented by Formula (9a) or Formula (9b) (since it is a symmetrical structure, only one terminal is described).

[0202] [Chemical formula 18]

[0203]

[0204] In formula (9a) and formula (9b), R 5 is a divalent hydrocarbon group having 1 to 8 carbon atoms, R 6 It is a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms.

[0205] In addition, l, m, s and u are 1≤l≤1000, 1≤m≤1000, 1≤s≤30, 0≤u≤10, respectively, and preferably 2≤l≤100, 10≤m≤500, 2≤s≤10, 1≤u≤10, respectively.

[0206] As the catalyst used for the ring-opening polymerization of cyclic-ε-caprolactone, a conventionally known catalyst can be used, but the catalyst is not limited thereto.

[0207] Specifically, examples include organic titanium compounds such as tetramethoxytitanium, tetraethoxytitanium, tetra-n-propoxytitanium, and tetrabutoxytitanium; organic tin compounds such as di-n-butyltin dilaurate, diisobutyltin oxide, and dibutyltin diacetate; acetates of magnesium, calcium, zinc, and the like; antimony oxide; stannous halide; perchloric acid, and the like.

[0208] The amount of the ring-opening polymerization catalyst added may be in the range of 10 to 10000 ppm, preferably 10 to 1000 ppm, based on the ε-caprolactone monomer (cyclic-ε-caprolactone).

[0209] As a method for introducing a polymerizable monomer having a free radical polymerizable unsaturated group into a poly-ε-caprolactone modified polyether, a reaction substrate (reactive functional group) of the polymerizable monomer and various catalysts corresponding to the skeleton formation can be used, and a conventionally known catalyst can be used as the catalyst.

[0210] Examples of the (esterification) catalyst used in the esterification reaction include Lewis acid catalysts such as alcoholates of titanium, zirconium, tin, aluminum and zinc, carboxylates of titanium, zirconium, tin, aluminum and zinc, or chelate compounds of titanium, zirconium, tin, aluminum and zinc, as well as boron trifluoride and boron trifluoride etherates; acid catalysts such as hydrochloric acid, sulfuric acid, hydrogen bromide, acetic acid, trifluoroacetic acid, methanesulfonic acid, and p-toluenesulfonic acid; amine catalysts such as pentamethyldiethylenetriamine (PMDETA), 1,4,7-trimethyl-1,4,7-triazacyclononane (TACN), triethylamine (TEA), N,N-dimethyl-4-pyridinamine (DMAP), 1,4-diazabicyclo(2,2,2)octane (DABCO), and tetramethylethylenediamine (TMEDA). Among them, amine catalysts are preferred from the viewpoint of stability of the product obtained by the esterification reaction and economy.

[0211] It should be noted that, in the case of using an amine catalyst, a dehydration condensation agent may be added to improve the reaction efficiency. As the dehydration condensation agent, a conventionally known dehydration condensation agent may be used, for example, 1,1'-carbonyldiimidazole (CDI), N,N'-dicyclohexylcarbodiimide (DCC), N,N'-diisopropylcarbodiimide (DIC), 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC), 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride (EDC-HCl) and 1-[bis(dimethylamino)methylene]-1H-1,2,3-triazolo[4,5-b]pyridinium 3-oxide hexafluorophosphate (HATU), etc., but not limited thereto.

[0212] As the (urethanization) catalyst used in the urethanization reaction, a conventionally known urethanization catalyst can be used, but the present invention is not limited thereto.

[0213] Specifically, examples include amines such as triethylamine, triethylenediamine, pentamethylenediethylenetriamine, N,N-dimethylethanolamine, 1,4-diazabicyclo(2,2,2)octane (DABCO), pyridine, and N,N,N',N'-tetramethyl-1,3-propylenediamine (TMPDA); organic tin compounds such as di-n-butyltin dilaurate, diisobutyltin oxide, dibutyltin diacetate, and dibutyltin dilaurate (DBTL); organic titanium compounds such as tetramethoxytitanium, tetraethoxytitanium, tetra-n-propoxytitanium, tetrabutoxytitanium, tetraacetylacetonatotitanium, and diisopropoxybis(ethyl acetoacetate); and organic zirconium compounds such as n-propyl zirconate, n-butyl zirconate, tetraacetylacetonatozirconium, and dibutoxybis(ethyl acetoacetate).

[0214] The amount of the catalyst added when introducing the polymerizable monomer having an unsaturated group capable of free radical polymerization may be in the range of 10 to 10000 ppm, preferably in the range of 10 to 1000 ppm, based on the polymerizable monomer.

[0215] During the above reaction, a polymerization inhibitor and an antioxidant may be used to inhibit the polymerization reaction of the (meth)acrylate group during the reaction. Specifically, examples of the polymerization inhibitor or antioxidant include hydroquinone, p-methoxyphenol, 2,6-di-tert-butyl-p-cresol, 2,4-dimethyl-6-tert-butylphenol, p-benzoquinone, and 2,5-dihydroxy-p-benzoquinone, but are not limited thereto.

[0216] In addition, as a method for producing a polyester-polyether copolymer, there can be mentioned a method of esterifying a poly-ε-caprolactone-modified (meth)acrylate represented by the following formula (10) with the above-mentioned carboxyl-modified polyether.

[0217] Examples of commercially available products of poly-ε-caprolactone-modified (meth)acrylates include PLACCEL FA2D, PLACCEL FA10L, PLACCEL FN2D and PLACCEL FM4 (manufactured by Daicel Corporation).

[0218] [Chemical formula 19]

[0219]

[0220] In the general formula (10), R 7 It is a hydrogen atom or a monovalent hydrocarbon group having 1 to 3 carbon atoms, preferably a hydrogen atom or a methyl group. v is 1≤v≤30, preferably 1≤v≤10.

[0221] As the production method, for example, the following production method can be mentioned, but it is not limited to this.

[0222] 1.0 to 1.25 mol of poly-ε-caprolactone modified (meth)acrylate (Formula (10)) and 0.1 to 5.0 mol of an esterification catalyst are mixed with 1.0 mol of carboxyl group of the carboxyl modified polyether in terms of hydroxyl equivalent, and stirred at 15 to 150° C. for about 10 to 30 minutes. 1.0 to 1.25 mol of a dehydration condensation agent is optionally added, and the mixture is reacted at 15 to 150° C. for 4 to 20 hours.

[0223] After the reaction, the reaction product is filtered, and by-products are removed by subjecting the reaction product to a water washing step and an adsorption treatment step, and the solvent is distilled off, thereby obtaining a polyester-polyether copolymer.

[0224] The polyester-polyether copolymer is preferably in liquid form, and the weight average molecular weight (M) measured by gel permeation chromatography (GPC) is W .) is preferably 100 to 100,000, more preferably 300 to 10,000.

[0225] When the weight average molecular weight is less than 100, the degradability of the obtained spherical elastomer particles may be poor, and when the weight average molecular weight is greater than 100,000, the preparation of the spherical elastomer particles may become difficult.

[0226] In the filtration step, a dilution operation using a hydrophobic organic solvent may be performed for the purpose of adjusting the viscosity of the reaction product.

[0227] The hydrophobic organic solvent used is not particularly limited, but is preferably toluene, hexane, ethyl acetate, or the like from the viewpoint of solubility and affinity.

[0228] The adsorption treatment step is a step for removing hydrochloride that cannot be removed by water washing and for dehydration, deodorization, and decolorization.

[0229] The adsorbent used in the adsorption treatment step may be any conventionally known adsorbent, and a combination of multiple adsorbents may be used. Preferred adsorbents include desiccants such as magnesium sulfate and sodium sulfate; activated carbon; KYOWAAD TM series (manufactured by Kyowa Chemical Industry Co., Ltd.), etc.

[0230] [Dispersion of spherical elastic particles]

[0231] The dispersion of the spherical elastomer particles of the present invention is a dispersion formed by dispersing the spherical elastomer particles in at least one dispersion medium selected from silicone oil, hydrocarbon oil, higher fatty acid, ester oil, liquid fat and water.

[0232] Examples of the dispersion medium include silicone oil, hydrocarbon oil, higher fatty acid, ester oil, liquid oil, and water, and silicone oil, hydrocarbon oil, ester oil, and water are preferred. Particularly preferred are dimethylpolysiloxane, decamethylcyclopentasiloxane, liquid paraffin, isododecane, squalane, stearic acid, oleic acid, butyl stearate, decyl oleate, distilled water, ion exchange water, and pure water.

[0233] The amount of the spherical particles of elastic body in the dispersion is preferably in the range of 5 to 80% by mass, more preferably in the range of 20 to 70% by mass, relative to the total mass of the dispersion. If the amount of the spherical particles of elastic body is less than the above lower limit, the average productivity of the spherical particles of elastic body decreases, which is not preferred due to the decrease in efficiency. In addition, if the amount of the spherical particles of elastic body is greater than the above upper limit, the viscosity of the dispersion increases, causing the operation to become difficult, which is not preferred.

[0234] [Method for producing a dispersion of spherical elastic particles and spherical elastic particles]

[0235] The elastic spherical particles of the present invention can be produced, for example, by a method comprising the following steps (i) to (iii). The dispersion of the elastic spherical particles of the present invention can also be produced by a method comprising the following steps (i) to (ii).

[0236] (i)

[0237] By stirring, emulsifying

[0238] (A) a copolymer having a polymerizable group and having a polyester structure and a polyether structure,

[0239] (B) an oil phase component or an aqueous phase component that does not dissolve the component (A),

[0240] (C) a surfactant, and

[0241] (D) a polymerization initiator, thereby preparing an O / O type emulsion or an O / W type emulsion;

[0242] (ii)

[0243] a step of obtaining a dispersion of elastic spherical particles by polymerizing the component (A) in the O / O type emulsion or O / W type emulsion obtained in the step (i);

[0244] (iii)

[0245] A step of obtaining elastic spherical particles by washing and drying the dispersion of the elastic spherical particles obtained in the step (ii) to remove the component (B) which is a continuous phase.

[0246] Process (i)

[0247] The components used in step (i) are as follows.

[0248] As the copolymer containing a polyester structure and a polyether structure having a polymerizable group as the component (A), a copolymer containing the polyester structure and the polyether structure having a polymerizable group as constituent units of the spherical elastic particles of the present invention can be used, and preferably a polyester-polyether copolymer having at least two free radical polymerizable unsaturated groups in one molecule can be used. As a specific example of the component (A), as described above, a polyester-polyether copolymer represented by the general formula (1) or the general formula (2) can be cited, and as a more preferred specific example, a polyester-polyether copolymer represented by the general formula (5) or the general formula (6) can be cited.

[0249] The component (B) is a component that forms a continuous phase of the emulsion and is an oil phase component or a water phase component that does not dissolve the component (A) (insoluble / incompatible) or has low affinity.

[0250] Examples of the oil phase component of the component (B) include silicone oil, hydrocarbon oil, higher fatty acid, ester oil, liquid oil, and the like. These may be used alone or in appropriate combinations of two or more, but are not limited thereto.

[0251] Examples of the silicone oil include dimethylpolysiloxane, methylhydrogenpolysiloxane, methylphenylpolysiloxane, octamethylsiloxane, decamethyltetrasiloxane, decamethylcyclopentasiloxane, hexamethylcyclotrisiloxane and octamethylcyclotetrasiloxane.

[0252] Examples of the hydrocarbon oil include liquid paraffin, α-olefin oligomers, isododecane, isohexadecane, squalane, ceresin, squalene, ceresin, paraffin, paraffin, polyethylene wax, polyethylene-polypropylene wax, pristane, polyisobutylene, vaseline, and microcrystalline wax.

[0253] Examples of the higher fatty acid include lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, undecylenic acid, oleic acid, linoleic acid, linolenic acid, arachidonic acid, eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), isostearic acid, and 12-hydroxystearic acid.

[0254] Examples of the ester oil include isopropyl myristate, cetyl octanoate, octyl dodecanol myristate, isopropyl palmitate, butyl stearate, hexyl laurate, myristyl myristate, decyl oleate, hexyl decyl dimethyl octanoate, cetyl lactate, myristyl lactate, lanolin acetate, isocetyl stearate, isocetyl isostearate, isononyl isononanoate, 12-hydroxystearate cholesterol, ethylene glycol di-2-ethylhexanoate, dipentaerythritol fatty acid ester, N-alkyl glycol monoisostearate, neopentyl glycol dicaprate, diisostearate malate, di-2-heptyl undecanoic acid glyceryl, trimethylolpropane tri-2-ethylhexanoate, trimethylolpropane triisostearate, tetra-2-ethylhexanoate, triisopalmityl triisostearate, trihexyl 2-ethylhexanoate, tricaprylin, triisopalmitin, trimethylolpropane triisostearate, 2-ethyl hexadecyl hexanoate, 2-ethylhexyl palmitate, trimyristin, tri-2-heptylundecanoic acid glyceryl, castor oil fatty acid methyl ester, oleyl oleate, acetylated glycerol, 2-heptylundecyl palmitate, diisobutyl adipate, 2-octyldodecyl N-lauroyl-L-glutamate, di-2-heptylundecyl adipate, ethyl laurate, di-2-ethylhexyl sebacate, 2-hexyldecyl myristic acid, 2-hexyldecyl palmitate, 2-hexyldecyl adipate, diisopropyl sebacate, 2-ethylhexyl succinate and triethyl citrate, etc.

[0255] Examples of the liquid oil include avocado oil, camellia oil, turtle oil, macadamia oil, corn oil, mink oil, olive oil, rapeseed oil, egg yolk oil, sesame oil, almond oil, wheat germ oil, camellia oil, castor oil, linseed oil, safflower oil, cottonseed oil, perilla oil, soybean oil, peanut oil, tea seed oil, ginkgo oil, rice bran oil, paulownia oil, tung oil, jojoba oil, germ oil, and triglycerol.

[0256] The kinematic viscosity of the component (B) at 25°C is preferably 100,000 mm 2 / s or less, more preferably 10000mm 2 When the kinematic viscosity is higher than the upper limit, emulsification may become difficult in step (i), or fine spherical particles having a narrow particle size distribution may be difficult to obtain.

[0257] When an aqueous phase component is used as the component (B), examples of the aqueous phase component of the component (B) include distilled water, ion-exchanged water, pure water, and ultrapure water.

[0258] The surfactant of the component (C) is not particularly limited, and examples thereof include nonionic surfactants, anionic surfactants, cationic surfactants, and amphoteric surfactants, which may be used alone or in appropriate combinations of two or more.

[0259] Examples of the nonionic surfactant include polyoxyethylene alkyl ethers, polyoxyethylene polyoxypropylene alkyl ethers, polyoxyethylene alkylphenyl ethers, polyethylene glycol fatty acid esters, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene sorbitol fatty acid esters, glycerol fatty acid esters, polyoxyethylene glycerol fatty acid esters, polyglycerol fatty acid esters, propylene glycol fatty acid esters, polyoxyethylene castor oil, polyoxyethylene hydrogenated castor oil, polyoxyethylene hydrogenated castor oil fatty acid esters, polyoxyethylene alkylamines, polyoxyethylene fatty acid amides, polyoxyethylene modified organopolysiloxanes, and polyoxyethylene polyoxypropylene modified organopolysiloxanes.

[0260] Examples of the polyoxyethylene-modified organic polysiloxane include linear polyether-modified silicone (trade name: KF-6015, KF-6017, KF-6017P, manufactured by Shin-Etsu Chemical Co., Ltd.), linear alkyl co-modified polyether-modified silicone (trade name: KF-6048, manufactured by Shin-Etsu Chemical Co., Ltd.), branched polyether-modified silicone (trade name: KF-6028, KF-6028P, manufactured by Shin-Etsu Chemical Co., Ltd.), and branched alkyl co-modified polyether-modified silicone (trade name: KF-6038, manufactured by Shin-Etsu Chemical Co., Ltd.).

[0261] Examples of the anionic surfactant include alkyl sulfate ester salts such as sodium lauryl sulfate, polyoxyethylene alkyl ether sulfate ester salts, polyoxyethylene alkylphenyl ether sulfate ester salts, alkylbenzene sulfonates, polyoxyethylene alkylphenyl ether sulfonates, alkyldiphenyl ether disulfonates, alkane sulfonates, N-acyltaurates, dialkyl sulfosuccinates, monoalkyl sulfosuccinates, polyoxyethylene alkyl ether sulfosuccinates, fatty acid salts, polyoxyethylene alkyl ether carboxylates, N-acylamino acid salts, monoalkyl phosphate ester salts, dialkyl phosphate ester salts, and polyoxyethylene alkyl ether phosphate ester salts.

[0262] Examples of the cationic surfactant include alkyltrimethylammonium salts, dialkyldimethylammonium salts, polyoxyethylene alkyldimethylammonium salts, dimeroxyethylene alkylmethylammonium salts, trimeroxyethylene alkylammonium salts, alkylbenzyldimethylammonium salts, alkylpyridinium salts, monoalkylamine salts and monoalkylamidoamine salts.

[0263] Examples of the amphoteric surfactant include alkyl dimethyl amine oxide, alkyl dimethyl carboxy betaine, alkyl amidopropyl dimethyl carboxy betaine, alkyl hydroxysulfonate, and alkyl carboxymethyl hydroxyethyl imidazolinium betaine.

[0264] As the surfactant, a nonionic surfactant or an anionic surfactant is preferred from the viewpoint that the oil phase component can be emulsified in a small amount and fine particles can be obtained.

[0265] When an oil phase component is used as the component (B), the surfactant (C) preferably has an HLB of 2.0 to 18.0.

[0266] When an aqueous phase component is used as the component (B), the surfactant (C) preferably has an HLB of 6.0 to 18.0, more preferably 9.0 to 18.0.

[0267] The amount of surfactant added is preferably 0.01 to 25 parts by mass, more preferably 0.05 to 15 parts by mass, relative to 100 parts by mass of the emulsion. When the amount of surfactant added is less than 0.01 parts by mass, emulsification may be poor or microparticles may not be obtained. In addition, when the amount of surfactant added is greater than 25 parts by mass, microparticles may not be obtained or the dispersibility of the elastic spherical particles may be insufficient.

[0268] In addition, the amount of component (A) in the emulsion is preferably 1.0 to 80 parts by mass, more preferably 10 to 60 parts by mass, relative to 100 parts by mass of the emulsion. When the amount of component (A) is less than 1.0 parts by mass, it becomes disadvantageous in terms of production efficiency, and when the amount of component (A) added is more than 80 parts by mass, it is sometimes difficult to obtain a dispersion of elastic spherical particles.

[0269] As the polymerization initiator of the component (D), a common radical polymerization initiator can be used, and in the presence of the initiator, a heating method, a redox method, a light irradiation method, or the like can be used to cause the reaction and curing to proceed.

[0270] As these polymerization initiators, peroxides, azo initiators, redox initiators in which an oxidizing agent and a reducing agent are combined, photopolymerization initiators, and the like can be used.

[0271] Examples of the peroxide include benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, o-methylbenzoyl peroxide, p-methylbenzoyl peroxide, 2,4-dicumyl peroxide, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, di-tert-butyl peroxide, tert-butyl benzoate, and hydrogen peroxide.

[0272] Alternatively, perchlorates such as potassium perchlorate and sodium perchlorate may be used.

[0273] Examples of the azo initiator include 2,2'-azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(2-methylpropionate), 2,2'-azobis(methylisobutyrate), tert-butyl peroxy-2-ethylhexanoate, and 2,2'-azobis(2-amidinopropane) dihydrochloride.

[0274] As the redox initiator, for example, an initiator combining ferrous sulfate, sodium pyrophosphate, glucose and hydrogen peroxide, and an initiator combining ferrous sulfate, disodium ethylenediaminetetraacetic acid, sodium formaldehyde sulfoxylate and hydrogen peroxide, etc. In addition, a thermal polymerization initiator and a photopolymerization initiator may be used in combination.

[0275] Examples of the photopolymerization initiator include 2,2-diethoxyacetophenone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 1-hydroxy-cyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropane-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)benzyl]phenyl}-2-methylpropane-1-one, methyl benzoylformate, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropane-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, and (2,4,6-trimethylbenzoyl)-diphenylphosphine oxide.

[0276] Furthermore, benzoin alkyl ethers such as benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether and benzoin isobutyl ether can also be used.

[0277] Among the above-mentioned polymerization initiators, peroxides, azo initiators, and photopolymerization initiators used in a heating method or a light irradiation method are preferred from the viewpoint of stability during emulsion polymerization reaction.

[0278] The amount of the polymerization initiator added is preferably in the range of 0.01 to 5.0 parts by mass relative to 100 parts by mass of component (A). When the amount of the polymerization initiator added is less than 0.01 parts by mass, poor curing may occur, and when the amount of the polymerization initiator added is greater than 5.0 parts by mass, odor or exudation may occur due to the mixing (contamination) of reaction residues, etc.

[0279] [Other additives]

[0280] In the method for producing the spherical particles of the elastic body of the present invention, in addition to the above-mentioned component (A), component (B), component (C) and component (D), various additives may be added in step (i) as required. As additives, for example, thickeners, preservatives, pH adjusting agents, antioxidants, polymerization inhibitors, etc. may be exemplified. They may be used alone or in appropriate amounts, two or more may be appropriately combined and used in appropriate amounts within the scope of not damaging the effects of the present invention.

[0281] There is no particular limitation on the order of adding and mixing the components in step (i). For example, after mixing components (A) and (D), components (B) and (C) may be added to the mixture of components (A) and (D) to prepare an emulsion. Alternatively, component (D) may be added after components (A), (B) and (C) are prepared into an emulsion.

[0282] Alternatively, after preparing an emulsion from components (A), (B), (C) and (D), component (B) may be further added to obtain a desired concentration before subjecting the emulsion to step (ii).

[0283] When preparing the emulsion for emulsification, a known emulsifying dispersing machine can be used. Examples of common emulsifying dispersing machines include high-speed rotating shearing type stirrers such as high-speed stirrers, high-speed rotating centrifugal radiation type stirrers such as HOMO DISPER, high-pressure jet emulsifying dispersing machines such as homogenizers, colloid mills, ultrasonic emulsifying machines, and propeller stirrers.

[0284] Step (ii)

[0285] The step (ii) is a step of polymerizing (curing, cross-linking) the component (A) in the emulsion prepared in the step (i) by the above-mentioned polymerization method to obtain a dispersion of elastic spherical particles.

[0286] The conditions for the polymerization reaction can be appropriately determined according to the type of the (D) polymerization initiator. For example, as the (D) polymerization initiator, when a peroxide or azo initiator is used, a heating method in which the polymerization reaction is carried out at a temperature of 30 to 80° C. for 10 to 24 hours can be mentioned; as the (D) polymerization initiator, when a redox initiator is used, a redox polymerization method in which the polymerization reaction is carried out at a temperature of 30 to 70° C. for 2 to 24 hours can be mentioned; as the (D) polymerization initiator, when a photopolymerization initiator is used, a light irradiation method in which the polymerization reaction is carried out under light irradiation can be mentioned.

[0287] In the case of the light irradiation method, regarding the light source and wavelength range used in light (UV) irradiation, a conventionally known light source and wavelength range can be used.

[0288] Process (iii)

[0289] In the step (iii), the component (B) which is a continuous phase is removed by washing and drying from the obtained dispersion of the elastomer spherical particles, thereby obtaining elastomer spherical particles.

[0290] When the continuous phase (dispersion medium) is an aqueous phase component, as a specific method of step (iii), for example, after the dispersion is concentrated by heating dehydration, filtration, centrifugal separation, decantation, etc., it is washed with water as needed, and finally heated and dried under normal pressure or reduced pressure; a method of spraying the dispersion in a heated air flow and heating and drying (spray drying method), or a method of heating and drying using a flowing heat medium, etc. In addition, as a method of removing the dispersion medium by reducing pressure after solidifying the dispersion, freeze drying method can also be mentioned. In the case where the elastic spherical particles obtained by removing the dispersion medium are agglomerated, they can also be crushed using a mortar or a jet mill.

[0291] When the continuous phase (dispersion medium) is an oil phase component, as a specific method of step (iii), a hydrophobic organic solvent is added to the dispersion of the spherical particles of the elastomer, and pressure filtration is performed after stirring for a predetermined time, thereby washing, removing and solvent replacement of the component (B). By repeating the washing operation several times, the component (B) can be fully removed and solvent replacement can be performed. As the hydrophobic organic solvent used at this time, toluene, hexane and ethyl acetate can be exemplified.

[0292] Thereafter, the elastomer spherical particles can be obtained by performing a method of heating and drying under normal pressure or reduced pressure, a method of heating and drying using a fluidized heat medium, a freeze-drying method, or the like.

[0293] [Example]

[0294] The present invention is described in more detail below with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples. In addition, in the examples, the kinematic viscosity is a value measured at 25°C, and the "%" indicating the concentration and content ratio means "mass %". The hardness (needle penetration) of the rubber cured product is a value measured in accordance with the standards of the Japanese Rubber Society Standard Standards (SRIS).

[0295] The molecular weight of the polyester-polyether copolymer (poly-ε-caprolactone acrylate-modified polyether) is a weight average molecular weight measured by GPC under the following conditions using polystyrene as a standard substance.

[0296] [Measurement conditions]

[0297] Elution solvent: tetrahydrofuran (THF)

[0298] Flow rate: 0.60mL / min

[0299] Detector: Differential Refractive Index Detector (RI)

[0300] Column: TSK Guardcolumn SuperH-H

[0301] TSKgel SuperHM-N

[0302] TSKgel SuperH2500

[0303] (All manufactured by Tosoh Corporation of Japan)

[0304] Column temperature: 40°C

[0305] Sample injection volume: 50 μL (0.5 mass % THF solution)

[0306] [Evaluation of biodegradability]

[0307] According to the OECD Guidelines for the Testing of Chemicals, No. 301F, July 17, 1992, "Ready Biodegradability: MANOMETRIC RESPIROMETRY TEST" standard, the biodegradability was measured by using activated sludge as a microbial (degradation) source, and the evaluation was performed based on the degree of biodegradation. The activated sludge used was activated sludge from a municipal sewage treatment plant, and the suspended matter concentration was 2400 mg / L. Sodium benzoate was used as the standard (control) substance.

[0308] As a method for measuring the biodegradability, the oxygen consumption (biochemical oxygen consumption (BOD)) in a closed system in an incubator was measured using a BOD measuring instrument, and the biodegradability was calculated according to the following formula.

[0309] Biodegradability (%) = BOD-B / TOD × 100-(11)

[0310] BOD: Biochemical oxygen consumption of test suspension or operation control (measured value: mg)

[0311] B: Average biochemical oxygen consumption of plant-derived blanks (measured value: mg)

[0312] TOD: The theoretical oxygen consumption required for complete oxidation of the test substance or sodium benzoate (calculated value: mg)

[0313] [Synthesis of poly-ε-caprolactone acrylate modified polyether 1]

[0314] In a 2L separable flask equipped with a stirring device, a thermometer, a cooling tube and a dropping funnel, 500g of terminal primary EO / PO polyether (manufactured by Sanyo Chemical Industries, Ltd., Japan, molecular weight 2000, OH group equivalent: 0.0975mol / 100g), 183.6g of ε-caprolactone (trade name: PLACCEL M, manufactured by Daicel Corporation, molecular weight 114.1) and 350g of dehydrated toluene were placed and heated to 90°C under nitrogen flow conditions. After reaching the target temperature, 0.68g of tetra-n-butyl titanate (molecular weight 340.0) as a catalyst was added and aged at 120°C for 4 to 6 hours.

[0315] Next, after the poly-ε-caprolactone modified polyether obtained by the above operation was cooled to near room temperature, 60.7 g of triethylamine (molecular weight 101.2), 100 g of dehydrated toluene and 0.22 g of butylated hydroxytoluene (BHT) (molecular weight 220.4) as a polymerization inhibitor were added, and stirred for a specified time. After it was evenly dissolved, 49.7 g of acryloyl chloride (molecular weight 90.5) was added dropwise using a dropping funnel, and after confirming the heat generation, it was aged at 60°C for 4 hours.

[0316] The obtained crude product was filtered under pressure, washed with sodium chloride aqueous solution using a separatory funnel, and centrifuged, and then magnesium sulfate, silica gel, activated carbon, etc. were added, and the powder was treated by vibration to remove impurities by adsorption. After various powders were removed by pressure filtration, 0.22 g of butylated hydroxytoluene (BHT) was added, and the solvent was distilled off at 60-70° C. and 50 mmHg or less, thereby obtaining poly-ε-caprolactone acrylate modified polyether 1 (the following formula (12), weight average molecular weight 2880).

[0317] [Chemical formula 20]

[0318]

[0319] [Synthesis of poly-ε-caprolactone acrylate modified polyether 2]

[0320] In a 1L separable flask equipped with a stirring device, a thermometer, a cooling tube and a dropping funnel, 300g of terminal primary EO / PO polyether (manufactured by Sanyo Chemical Industries, Ltd., Japan, molecular weight 2000, OH group equivalent: 0.0975mol / 100g), 110.2g of ε-caprolactone (trade name: PLACCEL M, manufactured by Daicel Corporation, molecular weight 114.1) and 200g of dehydrated toluene were placed and heated to 90°C under nitrogen flow conditions. After reaching the target temperature, 0.41g of tetra-n-butyl titanate (molecular weight 340.0) as a catalyst was added and aged at 120°C for 4 to 6 hours.

[0321] Next, after the poly-ε-caprolactone modified polyether obtained by the above operation was cooled to near room temperature, 100 g of dehydrated toluene and 0.96 g of dioctyl dineodecanoyl tin oxide (trade name: NEOSTANN U-830, manufactured by Nitto Kasei Co., Ltd., Japan, molecular weight 687.7) as a catalyst and 0.12 g of butylated hydroxytoluene (BHT) (molecular weight 220.4) as a polymerization inhibitor were added, and stirred for a prescribed time. After the mixture was uniformly dissolved, 44.4 g of 2-isocyanate ethyl acrylate (trade name: KarenzAOI, manufactured by Showa Denko K.K., Japan, molecular weight 141.1) was added dropwise using a dropping funnel, and after confirming heat generation, it was aged at 60°C for 4 hours.

[0322] After the obtained crude product was cooled to below 40°C, 0.8 g of ethanol was added to react with the unreacted (remaining) isocyanate group, and quenching treatment was performed. Then, magnesium sulfate, silica gel, activated carbon, etc. were added, and a powder treatment using vibration was performed to remove impurities by adsorption. After various powders were removed by pressure filtration, 0.12 g of butylated hydroxytoluene (BHT) was added, and the solvent was distilled off at 60-70°C and 50 mmHg or less, thereby obtaining poly-ε-caprolactone acrylate modified polyether 2 (the following formula (13), weight average molecular weight of 3120).

[0323] [Chemical formula 21]

[0324]

[0325] [Synthesis of poly-ε-caprolactone acrylate modified silicone]

[0326] In a 1L separable flask equipped with a stirring device, a thermometer, a cooling tube and a dropping funnel, 300g of carboxyl-modified silicone (molecular weight 1200, COOH group equivalent: 0.187mol / 100g), 202.8g of poly-ε-caprolactone monoacrylate (trade name: PLACCEL FA2D, manufactured by Daicel Corporation, molecular weight 344.0, OH group equivalent: 0.291mol / 100g), 200g of dehydrated toluene and 6.85g of 4-dimethylaminopyridine (DMAP) (manufactured by Tokyo Chemical Industry Co., Ltd., Japan, molecular weight 122.2) were placed and stirred and mixed in an ice bath. When the mixture was sufficiently cooled, a solution of 168.9 g of N,N'-dicyclohexylcarbodiimide (DCC) (manufactured by Tokyo Chemical Industry Co., Ltd., molecular weight 206.3) dissolved in 173.6 g of dehydrated toluene was added dropwise using a dropping funnel, and the mixture was aged for 20 hours at room temperature. After the aging, 200 g of toluene and 300 g of 0.5 mol / L hydrochloric acid were added for washing (to remove DMAP), and then a water washing treatment was carried out in the order of a saturated sodium bicarbonate aqueous solution and a 10% sodium chloride aqueous solution. After the above operation, 10 g of magnesium sulfate, silica gel, activated carbon, and Kyoward 700 (manufactured by Kyowa Chemical Industry Co., Ltd.) were added, and the mixture was vibrated to remove impurities by adsorption. After various powders were removed by pressure filtration, 0.09 g of butylated hydroxytoluene (BHT) was added as a polymerization inhibitor, and the solvent was distilled off at 60-70°C and below 10 mmHg to obtain poly-ε-caprolactone acrylate modified silicone (the following formula (14), weight average molecular weight: 2130).

[0327] [Chemical formula 22]

[0328]

[0329] [Example 1]

[0330] 60 g of poly-ε-caprolactone acrylate modified polyether 1 and 0.48 g of 2,2'-azobis(2,4-dimethylvaleronitrile) (hereinafter abbreviated as V-65) as a polymerization initiator were placed in a 500 ml container, and stirred and dissolved at 1000 rpm using a disperser. Next, 10 g of branched polyether modified silicone (trade name: KF-6028, manufactured by Shin-Etsu Chemical Co., Ltd., HLB: 4.0) and 50 g of decamethylcyclopentasiloxane (trade name: KF-995, manufactured by Shin-Etsu Chemical Co., Ltd., kinematic viscosity at 25°C: 4.0 mm) were added to the container. 2 / s), and thickening was confirmed when stirring at 4000-5000 rpm using a homogenizer, and when stirring was continued for further 10 minutes, an O / O type emulsion was obtained. Then, 80 g of decamethylcyclopentasiloxane was added while stirring at 1500-2000 rpm to dilute, thereby obtaining a white emulsion.

[0331] The emulsion was transferred to a 500 ml separable flask equipped with a stirring device having an anchor-type stirring blade, and the temperature was adjusted to 52 to 55° C. using an oil bath, and the mixture was stirred for 20 hours for aging to obtain a dispersion of elastic spherical particles.

[0332] About 100 g of toluene was added to the obtained dispersion of the elastic spherical particles, and after stirring for a predetermined time in a removable flask equipped with a stirring device with an anchor-type stirring blade, solid-liquid separation was performed by pressure filtration to remove the decamethylcyclopentasiloxane as a continuous phase. The above washing-separation operation was performed twice under the toluene solvent condition and once under the ethanol solvent condition, and the continuous phase was removed and the volatile solvent (<100° C.) was replaced.

[0333] Finally, the mixture was left to stand and dried in an air thermostatic chamber at 70° C. for more than 24 hours, thereby obtaining white to pale yellow powdery elastomer spherical particles of the target substance.

[0334] The obtained spherical elastomer particles were observed using an electron microscope (scanning microscope S-4700, manufactured by Hitachi High-Tech Corporation), and it was confirmed that the particles were spherical elastomer particles having a particle diameter of about 100 μm.

[0335] Furthermore, as a result of measuring an aqueous solution in which a surfactant was added to the obtained elastic spherical particles for redispersion by an electrical resistance method, it was confirmed that the volume average particle size of the elastic spherical particles was 98 μm.

[0336] The electron microscope photograph of the spherical particles of the elastomer containing the poly-ε-caprolactone acrylate modified polyether 1 of Example 1 is shown in Figure 1 .

[0337] By Figure 1 As can be seen from the electron microscope photograph shown, the aspect ratio of the elastomer spherical particles comprising the poly-ε-caprolactone acrylate-modified polyether 1 of Example 1 is approximately 1.

[0338] In addition, the hardness of the rubber constituting the rubber particles was measured in the following manner. 30.0 g of poly-ε-caprolactone acrylate modified polyether 1 and 0.24 g of 2,2'-azobis(2,4-dimethylvaleronitrile (trade name: V-65, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., Japan, molecular weight 248.4) were stirred and mixed, and injected into an aluminum culture dish to make it 10 mm thick. After standing for 1 hour under the condition of a 70°C air thermostat, a non-sticky (non-sticky) flat rubber was obtained. The hardness of the obtained flat rubber was measured, and the result was 73 when measured by an Asker C hardness meter and 55 when measured by an Asker A hardness meter.

[0339] According to the method, the biodegradability of poly-ε-caprolactone acrylate modified polyether 1 was evaluated for 60 days at a culture temperature of 22±1°C. The results showed that the biodegradability of poly-ε-caprolactone acrylate modified polyether 1 was 62% on average after 28 days and 73% on average after 60 days. Since the biodegradability after 28 days was 60%, which met the judgment standard, it was judged as a "readily biodegradable substance".

[0340] Therefore, it can be inferred that after using the poly-ε-caprolactone acrylate-modified polyether 1 or the elastomer spherical particles containing the poly-ε-caprolactone acrylate-modified polyether 1, when it flows directly into the ocean through the terrestrial water system, it will not continue to remain in the environment as a copolymer or particles, and will eventually degrade.

[0341] [Example 2]

[0342] Elastomer spherical particles were obtained in the same manner as in Example 1 except that linear polyether-modified silicone (trade name: KF-6017, manufactured by Shin-Etsu Chemical Co., Ltd., HLB: 4.5) was used instead of branched polyether-modified silicone (trade name: KF-6028) in the emulsifier.

[0343] When the obtained spherical elastic particles were observed with an electron microscope in the same manner as in Example 1, they were confirmed to be spherical elastic particles having a particle diameter of about 100 μm.

[0344] Furthermore, when a surfactant was added to an aqueous solution in which the obtained spherical elastic particles were redispersed, the spherical elastic particles were confirmed to have a volume average particle size of 72 μm.

[0345] [Example 3]

[0346] Elastomer spherical particles were obtained in the same manner as in Example 1, except that a linear polyether-modified silicone (trade name: KF-6017, manufactured by Shin-Etsu Chemical Co., Ltd., HLB: 4.5) was used in place of the branched polyether-modified silicone (trade name: KF-6028) in the emulsifier, and when the linear polyether-modified silicone was added, 20 g of a polyether-modified silicone gel active agent (trade name: KSG-210, manufactured by Shin-Etsu Chemical Co., Ltd.) was further added, and the amount of decamethylcyclopentasiloxane added during emulsification was changed from 50 g to 40 g.

[0347] When the obtained spherical elastic particles were observed with an electron microscope in the same manner as in Example 1, it was confirmed that the spherical elastic particles had a particle size slightly smaller than 100 μm.

[0348] Furthermore, when a surfactant was added to an aqueous solution to redisperse the obtained spherical elastic particles, the spherical elastic particles were confirmed to have a volume average particle size of 63 μm by an electrical resistance method.

[0349] [Example 4]

[0350] The continuous phase (B) was replaced by polydimethylsiloxane (trade name: KF-96-100cs, manufactured by Shin-Etsu Chemical Co., Ltd., with a kinematic viscosity of 100 mm at 25° C.) from cyclopentasiloxane. 2 Elastomer spherical particles were obtained by the same method as in Example 3 except for the above method.

[0351] When the obtained spherical elastic particles were observed with an electron microscope in the same manner as in Example 1, spherical elastic particles having a particle size of about 50 to 70 μm and a uniform particle size distribution were obtained.

[0352] Furthermore, when a surfactant was added to an aqueous solution to redisperse the obtained spherical elastic particles, the spherical elastic particles were measured by an electrical resistance method, and as a result, the volume average particle diameter of the spherical elastic particles was confirmed to be 57 μm.

[0353] [Example 5]

[0354] 60g of poly-ε-caprolactone acrylate modified polyether 2 and 0.48g of free radical polymerization initiator V-65 were placed in a 500ml container and stirred and dissolved at 1000rpm using a disperser. Then, 10g of linear polyether modified silicone (trade name: KF-6017, HLB: 4.5), 20g of polyether modified silicone gel active agent (trade name: KSG-210) and 40g of polydimethylsiloxane (trade name: KF-96-100cs, kinematic viscosity at 25°C is 100mm2 / s), and when stirred at 4000-5000 rpm using a homomixer, it was confirmed that the mixture thickened, and when stirring was continued for 10 minutes, an O / O type emulsion was obtained. Then, 70 g of cyclopentasiloxane was added while stirring at 1500-2000 rpm to dilute the mixture, thereby obtaining a white emulsion.

[0355] The steps after the preparation of the emulsion were carried out in the same manner as in Example 1, thereby obtaining elastic spherical particles.

[0356] When the obtained spherical elastic particles were observed with an electron microscope in the same manner as in Example 1, spherical elastic particles having a uniform particle size distribution and a particle size of about 20 to 50 μm were obtained.

[0357] Furthermore, as a result of measuring an aqueous solution in which a surfactant was added to the obtained elastic spherical particles for redispersion by an electrical resistance method, it was confirmed that the elastic spherical particles had a volume average particle size of 30 μm.

[0358] An electron micrograph of the spherical elastic particles containing poly-ε-caprolactone acrylate-modified polyether 2 of Example 5 is shown in Figure 2. As can be seen from the electron micrograph shown in Figure 2, the aspect ratio of the spherical elastic particles containing poly-ε-caprolactone acrylate-modified polyether 2 of Example 5 is approximately 1.

[0359] In addition, when the hardness of the rubber constituting the rubber particles was measured in the same manner as in Example 1, a non-sticky flat rubber was obtained. The hardness of the rubber was 76 when measured with an Asker C durometer and 62 when measured with an Asker A durometer.

[0360] According to the method, the results of the biodegradability evaluation of poly-ε-caprolactone acrylate modified polyether 2 were measured for 60 days under the culture temperature of 22±1°C. The biodegradability of poly-ε-caprolactone acrylate modified polyether 2 was 40% on average after 28 days and 65% on average after 60 days. Since the biodegradability after 60 days met the judgment criterion of 60%, it was judged to be an "intrinsically biodegradable substance".

[0361] Therefore, it can be inferred that after using poly-ε-caprolactone acrylate-modified polyether 2 or elastomer spherical particles containing poly-ε-caprolactone acrylate-modified polyether 2, when they flow directly into the ocean through terrestrial water systems, they will not continue to remain in the environment as copolymers or particles, and will eventually degrade.

[0362] [Example 6]

[0363] Elastomer spherical particles were obtained in the same manner as in Example 5 except that the amount of polydimethylsiloxane (trade name: KF-96-100cs), the component (B) serving as a continuous phase during emulsification, was changed from 40 g to 20 g.

[0364] When the obtained spherical elastic particles were observed with an electron microscope in the same manner as in Example 1, spherical elastic particles having a particle size of about 50 to 70 μm and a uniform particle size distribution were obtained.

[0365] Furthermore, as a result of measuring an aqueous solution in which a surfactant was added to the obtained elastic spherical particles and the particles were redispersed by an electrical resistance method, it was confirmed that the elastic spherical particles had a volume average particle size of 26 μm.

[0366] [Comparative Example]

[0367] When the rubber hardness of the poly-ε-caprolactone acrylate-modified silicone was measured in the same manner as in Example 1, a non-sticky (non-adhesive) flat rubber was obtained. The value of the rubber hardness was 71 as measured by an Asker C hardness meter.

[0368] According to the method, the biodegradability of poly-ε-caprolactone acrylate-modified silicone was evaluated at a culture temperature of 22±1°C for 28 days, and the biodegradability of poly-ε-caprolactone acrylate-modified silicone was maintained at an average of 26%. Since the biodegradability after 28 days was 60%, which did not meet the judgment standard, it was judged as a "non-readily biodegradable substance".

[0369] The dispersion of the copolymer and the spherical elastomer particles and the spherical elastomer particles of the present invention are expected to be particularly useful for cosmetics, etc., due to their characteristic structural composition. In addition, since the copolymer has a polyester (particularly poly-ε-caprolactone) structure and a polyether structure as a degradable skeleton in the powder or particle skeleton, it is expected that the copolymer will exhibit or be endowed with high biodegradability.

Claims

1. A polyester-polyether copolymer having at least two free radical polymerizable unsaturated groups in one molecule, which is represented by the following general formula (1) or general formula (2): [Chemical formula 1] In the general formula (1), R 1 Each independently represents a divalent hydrocarbon group having 1 to 10 carbon atoms, and R 2 Each independently represents an organic group containing a free radical polymerizable functional group represented by the following general formula (3a), general formula (3b) or general formula (3c), k is independently a number of 1≤k≤10, l is a number of 1≤l≤1000, m is a number of 1≤m≤1000, and n is independently a number of 1≤n≤100, In the general formula (2), R 3 Each independently represents a divalent hydrocarbon group having 1 to 10 carbon atoms, and R 4 Each independently represents an organic group containing a radical polymerizable functional group represented by the following general formula (4a) or general formula (4b), p is independently a number of 1≤p≤10, l is a number of 1≤l≤1000, m is a number of 1≤m≤1000, and q is independently a number of 1≤q≤100, [Chemical formula 2] In the general formula (3a), the general formula (3b), the general formula (3c), the general formula (4a) and the general formula (4b), R 5 Each independently represents a divalent hydrocarbon group having 1 to 8 carbon atoms, and R 6 Each represents a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms.

2. The polyester-polyether copolymer according to claim 1, It is represented by the following general formula (5): [Chemical formula 3] In the general formula (5), R 1 Each independently represents a divalent hydrocarbon group having 1 to 10 carbon atoms, and R 2 Each independently represents an organic group containing a radical polymerizable functional group represented by the following general formula (3a), general formula (3b) or general formula (3c), l is a number of 1≤l≤1000, m is a number of 1≤m≤1000, and r is a number of 1≤r≤100, [Chemical formula 4] In the general formula (3a), the general formula (3b) and the general formula (3c), R 5 Each independently represents a divalent hydrocarbon group having 1 to 8 carbon atoms, and R 6 Each represents a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms.

3. An elastic spherical particle having a volume average particle size of 0.5 to 200 μm, comprising a polymer containing a structural unit derived from a copolymer having a polyester structure and a polyether structure.

4. The spherical elastic particles according to claim 3, wherein: The copolymer is a polyester-polyether copolymer having at least two free radical polymerizable unsaturated groups in one molecule.

5. The spherical elastic particles according to claim 4, wherein The copolymer is a polyester-polyether copolymer represented by the following general formula (1) or general formula (2), [Chemical formula 5] In the general formula (1), R 1 Each independently represents a divalent hydrocarbon group having 1 to 10 carbon atoms, and R 2 Each independently represents an organic group containing a free radical polymerizable functional group represented by the following general formula (3a), general formula (3b) or general formula (3c), k is independently a number of 1≤k≤10, l is a number of 1≤l≤1000, m is a number of 1≤m≤1000, and n is independently a number of 1≤n≤100, In the general formula (2), R 3 Each independently represents a divalent hydrocarbon group having 1 to 10 carbon atoms, and R 4 Each independently represents an organic group containing a radical polymerizable functional group represented by the following general formula (4a) or general formula (4b), p is independently a number of 1≤p≤10, l is a number of 1≤l≤1000, m is a number of 1≤m≤1000, and q is independently a number of 1≤q≤100, [Chemical formula 6] In the general formula (3a), the general formula (3b), the general formula (3c), the general formula (4a) and the general formula (4b), R 5 Each independently represents a divalent hydrocarbon group having 1 to 8 carbon atoms, and R 6 Each represents a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms.

6. The spherical elastic particles according to claim 5, wherein The copolymer is a polyester-polyether copolymer represented by the following general formula (5): [Chemical formula 7] In the general formula (5), R 1 Each independently represents a divalent hydrocarbon group having 1 to 10 carbon atoms, and R 2 Each independently represents an organic group containing a radical polymerizable functional group represented by the following general formula (3a), general formula (3b) or general formula (3c), l is a number of 1≤l≤1000, m is a number of 1≤m≤1000, and r is a number of 1≤r≤100, [Chemical formula 8] In the general formula (3a), the general formula (3b) and the general formula (3c), R 5 Each independently represents a divalent hydrocarbon group having 1 to 8 carbon atoms, and R 6 Each represents a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms.

7. A dispersion of spherical elastic particles, which is formed by dispersing the spherical elastic particles according to any one of claims 3 to 6 in at least one dispersion medium selected from silicone oil, hydrocarbon oil, higher fatty acid, ester oil, liquid fat and water.

8. The method for producing spherical elastic particles according to any one of claims 3 to 6, wherein: The method comprises the following steps (i) to (iii), (i) By stirring and emulsifying (A) a copolymer having a polymerizable group and having a polyester structure and a polyether structure, (B) an oil phase component or an aqueous phase component that is insoluble in the component (A), (C) a surfactant, and (D) A step of preparing an O / O type emulsion or an O / W type emulsion by adding a polymerization initiator (ii) This is a step of obtaining a dispersion of elastic spherical particles by polymerizing the component (A) in the O / O type emulsion or O / W type emulsion obtained in the step (i). (iii) This is a step of obtaining elastic spherical particles by washing and drying the (B) component as a continuous phase from the dispersion of the elastic spherical particles obtained in the step (ii).

9. The manufacturing method according to claim 8, wherein: The step (i) is to stir and emulsify (A) a copolymer having a polymerizable group and having a polyester structure and a polyether structure, (B) an oil phase component that is insoluble in the component (A), (C) a surfactant, and (D) A step of obtaining an O / O type emulsion by adding a polymerization initiator.

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