Particle, molding material, molding, and method for producing them

Abstract

To provide particles which have excellent powder flowability and blocking resistance, and a molding material having excellent moldability.SOLUTION: Particles contain a (meth)acrylic copolymer (A) and a (meth)acrylic polymer (B), wherein (A) the (meth)acrylic copolymer (A) is a block copolymer and / or a graft copolymer, the (meth)acrylic polymer (B) is a random copolymer and / or a homopolymer, and the particles have a melt flow rate measured under the condition of 230°C and 3.8 kg according to JIS K 7210 (2014) of 10 g / 10 min or more. A molding material contains the particles.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to particles having excellent melt fluidity, powder fluidity and blocking resistance, a molding material containing the particles, a molded article molded from the molding material, and a method for producing the same. [Background technology]

[0002] Acrylic resins have excellent transparency, weather resistance, high elasticity, and surface hardness, and are therefore widely used in a variety of applications, including display front panels for liquid crystal and organic electroluminescence (EL) displays, signage, lighting supplies, toys, containers, home appliances, vehicle parts such as interior and exterior vehicle parts, medical components, industrial materials, construction materials, lenses, light guide plates, light collecting components, and optical components such as the optical films used in liquid crystal and organic electroluminescence (EL) displays. Some of these applications require acrylic resin products to be flexible and impact resistant, and there is also a demand for acrylic resins with excellent melt-moldability, which allows them to be molded into thin-walled or complex shapes using melt-molding methods such as injection molding and extrusion molding.

[0003] As a technique for improving the impact resistance of acrylic resins, for example, Patent Document 1 discloses a resin composition in which a rubber (core-shell rubber) having a core-shell structure, which has a core made of crosslinked rubber and a shell that ensures compatibility and dispersibility with the (meth)acrylic polymer that forms the matrix, is blended with a (meth)acrylic resin. However, the resin composition described in Patent Document 1 has a problem in that the inclusion of the core-shell rubber increases the melt viscosity and tends to reduce melt moldability, limiting the use of the resin composition to resin products with large thicknesses or simple shapes.

[0004] A known technique for improving the melt moldability of acrylic resins is to use resin compositions containing block copolymers and / or graft copolymers in combination with (meth)acrylic resins. Block copolymers and / or graft copolymers are composed of two or more polymer segments chemically linked together. Therefore, resin compositions containing block copolymers and / or graft copolymers with poly(meth)acrylate chains in combination with acrylic resins exhibit nanometer-sized phase-separated structures (referred to as "microphase-separated structures"). Therefore, in such resin compositions and molded articles obtained by molding such resin compositions, it is possible to achieve the combined properties of both the acrylic resin matrix and the block copolymer and / or graft copolymer, and furthermore, to achieve the combined properties of each polymer segment in the block copolymer and / or graft copolymer.

[0005]

[0004] As a method for producing the block copolymer and / or graft copolymer, there is a method for obtaining the copolymer as particles by suspension polymerization. The suspension polymerization method is superior to other polymerization methods such as emulsion polymerization and bulk polymerization in that it is easy to control the heat generated by polymerization and it is possible to remove impurities by washing the particles.

[0006] On the other hand, good powder flowability of particles is important for improving processability at manufacturing sites. Furthermore, the blocking resistance of particles is important for improving the handling properties of particles after long-term storage. For example, Patent Document 2 describes particles in which powder properties such as powder flowability and blocking resistance are improved by coating a rubber-containing graft copolymer with a hard non-elastic multistage copolymer.

[0007] However, the rubber-containing graft copolymer contained as an essential component in the particles described in Patent Document 2 has poor melt fluidity compared to block copolymers and / or graft copolymers, and therefore the moldability of molding materials using the resulting particles is poor. In other words, it has been difficult to obtain molding materials that have both excellent powder flowability and blocking resistance as particles and excellent moldability. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Special Publication No. 62-21804 [Patent Document 2] Japanese Patent Application Publication No. 4-300947 Summary of the Invention [Problem to be solved by the invention]

[0009] An object of the present invention is to provide particles having excellent powder flowability and blocking resistance, as well as a molding material and molded article having excellent moldability, and a method for producing the same. [Means for solving the problem]

[0010] As a result of extensive research, the present inventors have found that the above-mentioned problems can be solved by including a (meth)acrylic copolymer (A) which is a block copolymer and / or a graft copolymer and a (meth)acrylic polymer (B) which is a random copolymer and / or a homopolymer, and by providing particles having a melt flow rate within a specific range. That is, the present invention provides the following: <1> ~ <16> The summary is as follows.

[0011] <1> Particles containing a (meth)acrylic copolymer (A) and a (meth)acrylic polymer (B), wherein the (meth)acrylic copolymer (A) is a block copolymer and / or a graft copolymer, and the (meth)acrylic polymer (B) is a random copolymer and / or a homopolymer, and the particles have a melt flow rate of 10 g / 10 min or more as measured in accordance with JIS K7210 (2014) at 230°C and 3.8 kg.

[0012] <2> The particle diameter of the particles is 30 μm or more and 600 μm or less. <1> The particle according to claim 1.

[0013] <3> the content of the (meth)acrylic polymer (B) relative to 100 parts by mass of the (meth)acrylic copolymer (A) is 0.01 parts by mass or more and 20 parts by mass or less; <1> or <2> The particle according to claim 1.

[0014] <4> the (meth)acrylic polymer (B) is coated on the surface of the (meth)acrylic copolymer (A); <1> ~ <3> 1. The particle according to any one of the preceding items.

[0015] <5> the (meth)acrylic copolymer (A) contains a structural unit derived from a (meth)acrylic polymer (A1) and a structural unit derived from a (meth)acrylic polymer (A2), the (meth)acrylic polymer (A1) has a glass transition temperature of 50°C or higher, and the acrylic copolymer (A2) has a glass transition temperature of 0°C or lower; <1> ~ <4> 1. The particle according to any one of the preceding items.

[0016] <6> The (meth)acrylic polymer (B) has a glass transition temperature of 40°C or higher and lower than 80°C. <1> ~ <5> 1. The particle according to any one of the preceding items.

[0017] <7> The weight average molecular weight of the (meth)acrylic copolymer (A) is 50,000 or more and 2,500,000 or less. <1> ~ <6> 1. The particle according to any one of the preceding items.

[0018] <8> The weight average molecular weight of the (meth)acrylic polymer (B) is 50,000 or more and 5,000,000 or less. <1> ~ <7> 1. The particle according to any one of the preceding items.

[0019] <9> The (meth)acrylic copolymer (A) contains a graft copolymer. <1> ~ <8> 1. The particle according to any one of the preceding items.

[0020] <10> The (meth)acrylic polymer (A1) contains a structural unit derived from a macromonomer (a1) represented by the following general formula (1): <5> ~ <9> 1. The particle according to any one of the preceding items.

[0021] [ka]

[0022] (In formula (1), R 0 ~R n are each independently a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or a heterocyclic group. 1 ~X n are each independently a hydrogen atom or a methyl group. Z is a terminal group. n is a natural number from 1 to 10,000.

[0023] <11> the (meth)acrylic polymer (A1) contains 50% by mass or more and 100% by mass or less of repeating units derived from methyl methacrylate; <5> ~ <10> 1. The particle according to any one of the preceding items.

[0024] <12> The (meth)acrylic copolymer (A) is produced using a polymerizable composition (X) containing the macromonomer (a1) and a monomer (a2), and the monomer (a2) contains at least one selected from the group consisting of methyl acrylate, 4-hydroxybutyl acrylate, 2-hydroxyethyl acrylate, ethyl acrylate, n-propyl acrylate, i-propyl acrylate, n-butyl acrylate, i-butyl acrylate, t-butyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, tridecyl acrylate, and i-stearyl acrylate. <10> or <11> The particle according to claim 1.

[0025] <13> <1> ~ <12> A molding material comprising the particles according to any one of the preceding items.

[0026] <14> <13> A molded body obtained by molding the molding material according to claim 1.

[0027] <15> The method comprises the steps of obtaining a suspension containing the (meth)acrylic copolymer (A) by suspension polymerization, obtaining an emulsion containing the (meth)acrylic polymer (B) by emulsion polymerization, and mixing the suspension and the emulsion, followed by heat treatment at a temperature equal to or higher than the glass transition temperature (Tg) of the (meth)acrylic copolymer (B), <1> ~ <14> 1. A method for producing particles according to any one of the preceding claims.

[0028] <16> <15> 10. A method for producing a molded article, comprising molding a molding material produced by the method for producing particles according to claim 9. [Effects of the Invention]

[0029] The particles of the present invention have excellent powder flowability and blocking resistance, and furthermore, molding materials using these particles have excellent moldability. [Brief explanation of the drawings]

[0030] [Figure 1] FIG. 1 is an exploded perspective view showing an apparatus for preparing a sample for evaluating blocking resistance. DETAILED DESCRIPTION OF THE INVENTION

[0031] The present invention will be described in detail below. However, the following description is an example of an embodiment of the present invention, and the present invention is not limited to the following description as long as it does not deviate from the gist of the present invention. The present invention can be implemented in any modified form without departing from the gist of the present invention. In the present invention, "(meth)acrylic" means one or both of "acrylic" and "methacrylic". Furthermore, "(meth)acrylate" means one or both of "methacrylate" and "acrylate". The same applies to "(meth)acryloyl".

[0032] In the present invention, "monomer" refers to an unpolymerized compound (monomer component before polymerization), and "repeating unit" and "structural unit" refer to a structural unit constituting a polymer derived from a monomer formed by polymerization of the monomer. Furthermore, a structural unit constituting a polymer is referred to as a "monomer unit." A "repeating unit" or a "structural unit" may be a unit formed directly by a polymerization reaction, or may be a unit in which a portion of the unit is converted into a different structure by processing the polymer. In the present invention, "% by mass" indicates the content of a specific component contained in a total amount of 100% by mass. In the present invention, unless otherwise specified, a numerical range expressed using "to" in this specification means a range that includes the numerical values ​​written before and after "to" as the lower and upper limits, and "A to B" means A or more and B or less.

[0033] In the present invention, the weight average molecular weight (Mw) of the (meth)acrylic copolymer (A) and the (meth)acrylic polymer (B) refers to the weight average molecular weight, which is the relative molecular weight determined using gel permeation chromatography (GPC) and converted into polymethyl methacrylate (PMMA).

[0034] <Particle> The particles of the present invention contain a (meth)acrylic copolymer (A) and a (meth)acrylic polymer (B) as essential components. The (meth)acrylic copolymer (A) is a block copolymer and / or a graft copolymer, preferably a copolymer containing structural units derived from the (meth)acrylic polymer (A1) and the (meth)acrylic polymer (A2). The (meth)acrylic polymer (B) is a random copolymer and / or a homopolymer. The particles of the present invention are further characterized by a melt flow rate of 10 g / 10 min or more, measured at 230°C and 3.8 kg in accordance with JIS K7210 (2014), as described below.

[0035] <Particle size> The particle size of the particles of the present invention is the volume-based median size. The median size represents the diameter value at which, when a powder is divided into two particles of a certain particle size, the larger and smaller particles are equal in volume. In other words, the median size can be expressed as the 50% particle size. The particle size can be measured using a laser diffraction / scattering particle size distribution analyzer.

[0036] The lower limit of the particle size of the particles of the present invention is 10 μm or more, preferably 30 μm or more, more preferably 50 μm or more, even more preferably 100 μm or more, and particularly preferably 150 μm or more. A particle size of 10 μm or more improves the powder flowability and powder handleability of the particles. The upper limit of the particle size of the particles of the present invention is preferably 1,400 μm or less, more preferably 720 μm or less, even more preferably 700 μm or less, particularly preferably 600 μm or less, and most preferably 500 μm or less. A particle size of 1,400 μm or less is preferred because it facilitates washing, dehydration, drying, etc. of the particles. The above preferred upper and lower limits can be combined arbitrarily.

[0037] <Melt flow rate of particles> The particles of the present invention are characterized by having a melt flow rate of 10 g / 10 min or more, measured according to JIS K7210 (2014) at 230°C and 3.8 kg. The lower limit of the melt flow rate of the particles of the present invention is not particularly limited, but is preferably 15 g / 10 min or more, more preferably 20 g / 10 min or more, and even more preferably 25 g / 10 min or more. The upper limit of the melt flow rate of the particles of the present invention is not particularly limited, but is preferably 200 g / 10 min or less, more preferably 190 g / 10 min or less, and even more preferably 180 g / 10 min or less. When the melt flow rate of the particles is 10 g / 10 min or more, the moldability of the particles of the present invention and the molding material using the particles is good.When the melt flow rate of the particles is 200 g / 10 min or less, the spinnability during production of the molding material using the particles of the present invention is good, and production of the molding material is easy.

[0038] <(Meth)acrylic copolymer (A)> The particles of the present invention contain a (meth)acrylic copolymer (A). The (meth)acrylic copolymer (A) is a block copolymer and / or a graft copolymer.

[0039] The block copolymer and / or graft copolymer according to the present invention may have any structure such as diblock, triblock, multiblock, graft, cyclic, star, comb, dendritic, or ladder structure, or may have a structure in which a plurality of these structures are combined. Among these structures, the (meth)acrylic copolymer (A) preferably contains at least one of the diblock, triblock, and graft structures, because it can impart excellent impact resistance and flexibility and is relatively easy to produce. In particular, the (meth)acrylic copolymer (A) preferably contains a graft copolymer.

[0040] The block copolymer and / or graft copolymer according to the present invention preferably contains a (meth)acrylic polymer (A1) and a (meth)acrylic polymer (A2) described below in the polymer molecule. In one embodiment of this case, the block copolymer and / or graft copolymer may be a graft copolymer in which the main chain is constituted by a (meth)acrylic polymer (A1), and a graft chain made of a (meth)acrylic polymer (A2) is branched and connected to the main chain made of the (meth)acrylic polymer (A1). Conversely, the main chain may be a (meth)acrylic polymer (A2) and the side chain may be a (meth)acrylic polymer (A1). The block copolymer and / or graft copolymer may be a block copolymer in which a polymer made of a (meth)acrylic polymer (A1) and a polymer made of a (meth)acrylic polymer (A2) are connected in series. Furthermore, the main chain and / or side chain of the graft copolymer may have a structure containing a block copolymer.

[0041] In the block copolymer and / or graft copolymer of the (meth)acrylic copolymer (A), the (meth)acrylic polymer (A1) preferably has the function of imparting miscibility or compatibility with the matrix resin when other matrix resins are contained, or the function of enabling the particles of the present invention to be handled as a solid. In addition, in the block copolymer and / or graft copolymer of the (meth)acrylic copolymer (A), the (meth)acrylic polymer (A2) preferably has the function of imparting flexibility, impact resistance, moldability, etc.

[0042] The lower limit of the weight-average molecular weight (Mw) of the (meth)acrylic copolymer (A) in terms of PMMA is preferably 50,000 or more, more preferably 100,000 or more, even more preferably 300,000 or more, and particularly preferably 600,000 or more. If the lower limit of Mw of the (meth)acrylic copolymer (A) is 50,000 or more, performance properties such as heat resistance, hardness, scratch resistance, weather resistance, and transparency are easily exhibited. Furthermore, the upper limit of Mw of the (meth)acrylic copolymer (A) is preferably 2,500,000 or less, more preferably 2,000,000 or less, and even more preferably 1,500,000 or less. If the upper limit of Mw of the (meth)acrylic copolymer (A) is 2,500,000 or less, the melt viscosity falls within an appropriate range, resulting in good miscibility of the resulting particles of the present invention with other resins, such as matrix resins, and good processability of molding materials containing the resulting particles of the present invention.

[0043] The (meth)acrylic copolymer (A) can be used alone or in combination of two or more.

[0044] [(Meth)acrylic polymer (A1)] The (meth)acrylic polymer (A1) preferably contains 50% by mass or more and 100% by mass or less of repeating units derived from methyl methacrylate (hereinafter, may be referred to as "methyl methacrylate units") relative to 100% by mass of the total weight of the (meth)acrylic polymer (A1). The (meth)acrylic polymer (A1) preferably contains 80% by mass or more, even more preferably 90% by mass or more, and particularly preferably 95% by mass or more, of methyl methacrylate units relative to 100% by mass of the total weight of the polymer. It is preferable that the lower limit of the content of methyl methacrylate units in the (meth)acrylic polymer (A1) is 50% by mass or more relative to 100% by mass of the total weight of the (meth)acrylic polymer (A1), since the (meth)acrylic polymer (A1) has good affinity with the matrix resin and good miscibility and compatibility. On the other hand, the upper limit of the content of methyl methacrylate units is not particularly limited as long as it is 100% by mass or less, and the (meth)acrylic polymer (A1) may be a homopolymer containing 100% by mass of methyl methacrylate units.

[0045] The (meth)acrylic polymer (A1) may contain, in addition to the methyl methacrylate units, units derived from other comonomers copolymerizable with methyl methacrylate (hereinafter, sometimes referred to as "comonomer units") depending on the purpose. For example, when the (meth)acrylic polymer (A1) contains an acrylate unit as a comonomer unit, depolymerization of the (meth)acrylic polymer (A1) can be suppressed when exposed to high-temperature conditions such as those in a melt molding method, which is preferable in terms of improving thermal decomposition resistance. Furthermore, by adjusting the type and content of the comonomer unit, it is possible to control the physical properties and functions of the (meth)acrylic polymer (A1), such as the glass transition temperature (Tg), processability, heat resistance, refractive index, weather resistance, releasability, and thermal decomposition resistance.

[0046] The upper limit of the content of the comonomer unit in the (meth)acrylic polymer (A1) is preferably 50% by mass or less relative to the total mass (100% by mass) of the (meth)acrylic polymer (A1), in order to maintain good performance such as heat resistance, hardness, scratch resistance, weather resistance, transparency, processability, etc. On the other hand, the lower limit of the content of the comonomer unit may be 0% by mass.

[0047] Examples of the comonomers that form the comonomer units of the (meth)acrylic polymer (A1) include the following a) to i). a) (Meth)acrylate ester monomers other than methyl methacrylate, such as methyl acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, i-propyl (meth)acrylate, n-butyl (meth)acrylate, i-butyl (meth)acrylate, t-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-lauryl (meth)acrylate, n-stearyl (meth)acrylate, cyclohexyl (meth)acrylate, phenyl (meth)acrylate, benzyl (meth)acrylate, isobornyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, and phenoxyethyl (meth)acrylate. b) Hydroxyl group-containing (meth)acrylate monomers such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and glycerol (meth)acrylate. c) Carboxyl group-containing vinyl monomers such as (meth)acrylic acid, 2-(meth)acryloyloxyethyl hexahydrophthalic acid, 2-(meth)acryloyloxypropyl hexahydrophthalic acid, 2-(meth)acryloyloxyethyl phthalic acid, 2-(meth)acryloyloxypropyl phthalic acid, 2-(meth)acryloyloxyethyl maleic acid, 2-(meth)acryloyloxypropyl maleic acid, 2-(meth)acryloyloxyethyl succinic acid, 2-(meth)acryloyloxypropyl succinic acid, crotonic acid, fumaric acid, maleic acid, itaconic acid, monomethyl maleate, and monomethyl itaconate. d) Vinyl monomers containing an acid anhydride group, such as maleic anhydride and itaconic anhydride. e) Epoxy group-containing vinyl monomers such as glycidyl (meth)acrylate, glycidyl α-ethyl acrylate, and 3,4-epoxybutyl (meth)acrylate. f) Amino group-containing (meth)acrylate vinyl monomers such as dimethylaminoethyl (meth)acrylate and diethylaminoethyl (meth)acrylate. g) Vinyl monomers containing an amide group, such as (meth)acrylamide, Nt-butyl(meth)acrylamide, N-methylol(meth)acrylamide, N-methoxymethyl(meth)acrylamide, N-butoxymethyl(meth)acrylamide, diacetone acrylamide, maleic acid amide, and maleimide. h) Vinyl monomers such as styrene, α-methylstyrene, vinyltoluene, (meth)acrylonitrile, vinyl chloride, vinyl acetate, and vinyl propionate i) Polyfunctional vinyl monomers such as divinylbenzene, ethylene glycol di(meth)acrylate, 1,3-butylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, allyl (meth)acrylate, and N,N'-methylenebis(meth)acrylamide.

[0048] These may be used alone or in combination of two or more.

[0049] Among these, in terms of easy availability of the monomer, methyl acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate are preferred, and methyl acrylate is more preferred.

[0050] The (meth)acrylic polymer (A1) preferably contains a structural unit derived from the macromonomer (a1) described below. In this case, the macromonomer (a1) may contain a methyl methacrylate unit.

[0051] The glass transition temperature (Tg) of the (meth)acrylic copolymer (A1) is preferably 50° C. or higher, more preferably 55° C. or higher, even more preferably 60° C. or higher, and particularly preferably 65° C. or higher. A glass transition temperature (Tg) of the (meth)acrylic copolymer (A1) of 50° C. or higher is preferred because the molding material containing the particles of the present invention has excellent heat resistance. On the other hand, there is no particular restriction on the upper limit of the Tg of the (meth)acrylic polymer (A1), but it is usually 120° C. or lower from the viewpoint of the processability of the molding material containing the particles of the present invention.

[0052] In the present invention, the Tg of the (meth)acrylic polymer (A1) and the (meth)acrylic polymer (A2) and (B) described below can be calculated from the glass transition temperature and mass fraction of the homopolymer by the Fox formula described in Polymer Handbook [Polymer Handbook, J. Brandrup, Interscience, 1989], or the tan δ value obtained by measuring the dynamic viscoelasticity of the obtained molded article can be used as the Tg. The Fox formula is as follows: 1 / (273+Tg)=Σ(Wi / (273+Tgi)) In the formula, Wi is the mass fraction of monomer i, and Tgi is the glass transition temperature (°C) of the homopolymer of monomer i. When a monomer whose homopolymer glass transition temperature is not described in the Polymer Handbook is used, the Tg used is a value measured by a differential scanning calorimeter (DSC).

[0053] The (meth)acrylic polymer (A1) preferably has a weight-average molecular weight (Mw) in terms of PMMA of 5,000 to 100,000, more preferably 10,000 to 70,000, and even more preferably 15,000 to 50,000. If the lower limit of Mw of the (meth)acrylic polymer (A1) is 5,000 or more, the (meth)acrylic copolymer (A) is more likely to exhibit its properties, such as heat resistance, hardness, scratch resistance, weather resistance, and transparency. Furthermore, if the upper limit of Mw of the (meth)acrylic polymer (A1) is 100,000 or less, the melt viscosity falls within an appropriate range, resulting in favorable miscibility and processability, which is preferred.

[0054] The (meth)acrylic polymer (A1) in the present invention may be a mixture of two or more polymers. In this case, the weight-average molecular weight (Mw) is calculated as the value for the entire (meth)acrylic polymer (A1). In one embodiment when multiple (meth)acrylic polymers (A1) with different weight-average molecular weights (Mw) are used in combination, the (meth)acrylic polymer (A1) with a lower molecular weight plays a role in reducing syrup viscosity and preventing crosslinking of the copolymer, while the (meth)acrylic polymer (A1) with a higher molecular weight plays a role in ensuring compatibility with the matrix resin when used as an additive.

[0055] The content of the (meth)acrylic polymer (A1) in the (meth)acrylic copolymer (A) is preferably 35% by mass or more and 75% by mass or less, based on 100% by mass of the total weight of the (meth)acrylic copolymer (A). If the lower limit of the content of the (meth)acrylic polymer (A1) is 35% by mass or more, it becomes easier to obtain particles containing the (meth)acrylic copolymer (A) that have excellent miscibility and compatibility with the matrix resin. The lower limit of the content of the (meth)acrylic polymer (A1) is preferably 40% by mass or more, more preferably 45% by mass or more, even more preferably 50% by mass or more, and most preferably 55% by mass or more. On the other hand, if the upper limit of the content of the (meth)acrylic polymer (A1) is 75% by mass or less, it becomes easier to obtain the effect of imparting flexibility by the (meth)acrylic polymer (A2). The upper limit of the content of the (meth)acrylic copolymer (A1) is preferably 70% by mass or less, more preferably 65% ​​by mass or less.

[0056] [(Meth)acrylic polymer (A2)] The (meth)acrylic polymer (A2) is preferably contained because it imparts functions such as flexibility, impact resistance, and improved flowability during melt molding to the particles of the present invention containing the (meth)acrylic copolymer (A) and molding materials and molded articles using the particles.

[0057] The glass transition temperature (Tg) of the (meth)acrylic polymer (A2) is preferably 0° C. or lower, more preferably −10° C. or lower, even more preferably −20° C. or lower, and particularly preferably −35° C. or lower. A glass transition temperature (Tg) of the (meth)acrylic polymer (A2) of 0° C. or lower is preferred because it provides superior flexibility, impact resistance, and fluidity during melt molding. On the other hand, there is no particular restriction on the lower limit of Tg of the (meth)acrylic polymer (A2), but it is usually −50° C. or higher from the viewpoint of the spinnability required during the production of a molding material.

[0058] The weight-average molecular weight (Mw) of the (meth)acrylic polymer (A2) can be determined by dividing the Mw of the (meth)acrylic copolymer (A) by the charge ratio of the (meth)acrylic copolymer (A1) and the (meth)acrylic copolymer (A2). The weight-average molecular weight (Mw) of the (meth)acrylic polymer (A2) determined by the above-described calculation method is preferably 150,000 or more, more preferably 200,000 or more, and even more preferably 250,000 or more. If the lower limit of Mw of the (meth)acrylic polymer (A2) is 150,000 or more, the impact resistance and flexibility of the molding material containing the particles of the present invention are improved. The weight-average molecular weight (Mw) of the (meth)acrylic polymer (A2) determined by the above-described calculation method is preferably 700,000 or less, more preferably 650,000 or less, and even more preferably 600,000 or less. It is preferable that the upper limit of Mw of the (meth)acrylic polymer (A2) is 700,000 or less, since the particles of the present invention have excellent miscibility with other resins, such as matrix resins, and the processability of the resulting molding material containing the particles of the present invention is good.

[0059] The (meth)acrylic polymer (A2) in the present invention may be a mixture of two or more polymers. In this case, the weight-average molecular weight (Mw) is calculated as the value for the entire (meth)acrylic polymer (A2). In one embodiment when multiple (meth)acrylic polymers (A2) with different weight-average molecular weights (Mw) are used in combination, the (meth)acrylic polymer (A2) with a lower molecular weight plays a role in reducing syrup viscosity and preventing crosslinking of the copolymer, while the (meth)acrylic polymer (A2) with a higher molecular weight plays a role in ensuring compatibility with the matrix resin when used as an additive.

[0060] The content of the (meth)acrylic polymer (A2) in the (meth)acrylic copolymer (A) is preferably 25% by mass or more and 65% by mass or less, based on the total weight of the (meth)acrylic copolymer (A) (100% by mass). If the lower limit of the content of the (meth)acrylic polymer (A2) is 25% by mass or more, the (meth)acrylic copolymer (A) is more likely to improve the flexibility, impact resistance, and moldability of the molding material. The lower limit of the content of the (meth)acrylic polymer (A2) is preferably 25% by mass or more, more preferably 30% by mass or more, and even more preferably 35% by mass or more. On the other hand, if the upper limit of the content of the (meth)acrylic polymer (A2) is 65% by mass or less, the particles of the present invention are easy to handle. The upper limit of the content of the (meth)acrylic polymer (A2) is preferably 65% ​​by mass or less, more preferably 60% by mass or less, even more preferably 55% by mass or less, particularly preferably 50% by mass or less, and most preferably 45% by mass or less.

[0061] The (meth)acrylic polymer (A2) preferably comprises repeating units derived from the monomer (a2) shown below, which is obtained as a raw material.

[0062] [Monomer (a2)] Monomer (a2) is a monomer used as a raw material for the (meth)acrylic polymer (A2), and is preferably a component copolymerizable with the macromonomer (a1) described below. Monomer (a2) is not particularly limited as long as it can produce the (meth)acrylic copolymer (A), which is a block copolymer and / or a graft copolymer, and various polymerizable monomers can be used as needed. Specifically, it is preferable to mainly use acrylates or aromatic vinyls in order to set a low glass transition temperature (Tg) to impart flexibility, impact resistance, and moldability, and to adjust the refractive index. Furthermore, other monomers can be used as needed.

[0063] The acrylate content of monomer (a2) is preferably 70% by mass or more, more preferably 79% by mass or more, and even more preferably 81% by mass or more, based on 100% by mass of the total weight of monomer (a2). If the lower limit of the acrylate content is 70% by mass or more, molded articles obtained using the particles of the present invention have superior flexibility and impact resistance, and molding materials containing the particles of the present invention have excellent moldability. The upper limit of the acrylate content in monomer (a2) is not particularly limited, but is preferably less than 100% by mass, more preferably 95% by mass or less, and even more preferably 90% by mass or less, based on 100% by mass of the total mass of monomer (a2).

[0064] Furthermore, the acrylate used for the monomer (a2) preferably has a glass transition temperature (Tg) of less than 0°C as a homopolymer of the acrylate, since this allows the obtained molded article to have better impact resistance. In the present invention, the Tg of the acrylate homopolymer can be calculated using the Fox formula using values ​​described in known documents such as the Polymer Handbook (POLYMER HANDBOOK FOURTH EDITION 2003).

[0065] Examples of the acrylate used in the monomer (a2) include the following known acrylates: methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, hexyl acrylate, heptyl acrylate, octyl acrylate, nonyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, stearyl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate, isobornyl acrylate, 2-methoxyethyl acrylate, 2-ethoxyethyl acrylate, phenoxyethyl acrylate, tridecyl acrylate, and other acrylates; hydroxyl group-containing acrylates such as 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, and glycerol acrylate; 2-acryloyloxyethyl hexahydrophthalic acid, 2-acryloyloxypropyl hexahydrophthalic acid, 2-acryloyloxyethyl phthalic acid, 2-acryloyloxyethyl acrylate ... Examples of suitable acrylates include carboxyl group-containing acrylates such as propyl phthalate, 2-acryloyloxyethyl maleate, 2-acryloyloxypropyl maleate, 2-acryloyloxyethyl succinate, and 2-acryloyloxypropyl succinate; epoxy group-containing acrylates such as glycidyl acrylate, glycidyl α-ethyl acrylate, and 3,4-epoxybutyl acrylate; amino group-containing acrylates such as dimethylaminoethyl acrylate and diethylaminoethyl acrylate; and polyfunctional acrylates such as ethylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,6-hexanediol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, tripropylene glycol diacrylate, trimethylolpropane triacrylate, allyl acrylate, and N,N'-methylenebisacrylamide. These may be used alone or in combination of two or more.

[0066] Among the above-mentioned monomers, 4-hydroxybutyl acrylate, 2-hydroxyethyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, phenyl acrylate, hexyl acrylate, heptyl acrylate, octyl acrylate, nonyl acrylate, lauryl acrylate, tridecyl acrylate, and 2-ethylhexyl acrylate are preferred because the Tg of the homopolymer of the monomer is less than 0° C. Furthermore, ethyl acrylate and butyl acrylate are preferred because they are easily available.

[0067] The aromatic vinyl that can be used for the monomer (a2) is used for the purpose of adjusting the refractive index of the (meth)acrylic polymer (A2) and adjusting the polymerization rate when producing the (meth)acrylic polymer (A2) and the (meth)acrylic copolymer (A). The lower limit of the content of the aromatic vinyl used in the monomer (a2) is preferably 10% by mass or more, more preferably 13% by mass or more, and even more preferably 15% by mass or more, based on 100% by mass of the total mass of the monomer (a2). If the content of the aromatic vinyl contained in the monomer (a2) is 10% by mass or more, it is preferable that the molding material and molded article using the particles of the present invention can exhibit good transparency. The upper limit of the content of the aromatic vinyl used in the monomer (a2) is preferably 30% by mass or less, more preferably 21% by mass or less, and even more preferably 19% by mass or less, based on 100% by mass of the total mass of the monomer (a2). If the content of the aromatic vinyl contained in the monomer (a2) is 30% by mass or less, it is preferable from the viewpoint of sufficiently increasing the polymerization reaction rate when producing the (meth)acrylic copolymer (A). The upper and lower limits can be combined arbitrarily, but are preferably 10 to 30 mass %, more preferably 13 to 21 mass %, and even more preferably 15 to 19 mass %.

[0068] Examples of aromatic vinyls include styrene, α-methylstyrene, o-methylstyrene, p-methylstyrene, o-ethylstyrene, p-ethylstyrene, pt-butylstyrene, vinylethylbenzene, vinyltoluene, vinylxylene, vinylnaphthalene, diphenylethylene, and divinylbenzene. Among these, styrene is preferred from the viewpoint of practical properties and productivity. These can be used alone or in combination of two or more.

[0069] The monomer (a2) in the present invention may contain other monomers copolymerizable with the acrylate and the aromatic vinyl, if necessary. Other monomers include, for example, methacrylates such as methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, i-propyl methacrylate, n-butyl methacrylate, i-butyl methacrylate, t-butyl methacrylate, 2-ethylhexyl methacrylate, n-lauryl methacrylate, n-stearyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, benzyl methacrylate, isobornyl methacrylate, 2-methoxyethyl methacrylate, 2-ethoxyethyl methacrylate, and phenoxyethyl methacrylate; hydroxyl group-containing methacrylates such as 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, and glycerol methacrylate; 2-methacryloyloxyethyl hexahydrophthalic acid, 2-methacryloyloxypropyl hexahydrophthalic acid, and 2-methacryloyl Examples of suitable methacrylates include carboxyl group-containing methacrylates such as oxyethyl phthalate, 2-methacryloyloxypropyl phthalate, 2-methacryloyloxyethyl maleate, 2-methacryloyloxypropyl maleate, 2-methacryloyloxyethyl succinate, and 2-methacryloyloxypropyl succinate; epoxy group-containing methacrylates such as glycidyl methacrylate and 3,4-epoxybutyl methacrylate; amino group-containing methacrylates such as dimethylaminoethyl methacrylate and diethylaminoethyl methacrylate; and polyfunctional methacrylates such as ethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,6-hexanediol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, tripropylene glycol dimethacrylate, trimethylolpropane trimethacrylate, and allyl methacrylate. These may be used alone or in combination. Further, examples of other monomers include carboxyl group-containing vinyl monomers such as (meth)acrylic acid, crotonic acid, fumaric acid, maleic acid, itaconic acid, monomethyl maleate, and monomethyl itaconate; acid anhydride group-containing vinyl monomers such as maleic anhydride and itaconic anhydride; amide group-containing vinyl monomers such as (meth)acrylamide, Nt-butyl(meth)acrylamide, N-methylol(meth)acrylamide, N-methoxymethyl(meth)acrylamide, N-butoxymethyl(meth)acrylamide, diacetone acrylamide, maleic acid amide, and maleimide; and vinyl monomers such as (meth)acrylonitrile, vinyl chloride, vinyl acetate, and vinyl propionate. When the monomer (a2) contains other monomers, the content thereof is preferably 20% by mass or less, more preferably 10% by mass or less, and even more preferably 5% by mass or less, relative to 100% by mass of the total of the monomers (a2), and may not be used.

[0070] [(Meth)acrylic polymer (B)] The particles of the present invention contain a (meth)acrylic polymer (B) as an essential component. The (meth)acrylic polymer (B) is a random copolymer and / or a homopolymer. In the particles of the present invention, the (meth)acrylic polymer (B) preferably covers at least a part of the surface of the (meth)acrylic copolymer (A), and more preferably covers the entire surface. The (meth)acrylic copolymer (B) has the effect of preventing particles from being difficult to separate when they come into contact with each other, and contributes to the powder flowability and blocking resistance of the particles of the present invention.

[0071] The monomer units constituting the (meth)acrylic copolymer (B) are not particularly limited, but preferably contain a monomer unit (b1) represented by the following formula (3).

[0072] [ka]

[0073] In the formula (3), R 10 represents a hydrogen atom or a methyl group, and R 11 are hydrogen atoms, halogen atoms, OH, OR 36 , C.N., N.R. 40 R 41 or R 42 and R 36 , R 40 , R 41 each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alicyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, a substituted or unsubstituted non-aromatic heterocyclic group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted alkaryl group, or a substituted or unsubstituted organosilyl group; R 42 represents a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group.

[0074] Examples of the monomer that forms the monomer unit (b1) (hereinafter, may be referred to as "monomer (b1)") include the following monomers. Methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, isoamyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, isooctyl (meth)acrylate, nonyl (meth)acrylate, isononyl (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, lauryl (meth)acrylate, hexadecyl (meth)acrylate, (meth)acrylate Hydrocarbon group-containing (meth)acrylic acid esters such as stearyl (meth)acrylate, isostearyl (meth)acrylate, phenyl (meth)acrylate, benzyl (meth)acrylate, cyclohexyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, isobornyl (meth)acrylate, 3,5,5-trimethylcyclohexyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, terpene acrylate and derivatives thereof, hydrogenated rosin acrylate and derivatives thereof, and docosyl (meth)acrylate.

[0075] Hydroxyl group-containing (meth)acrylic acid esters such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and glycerol (meth)acrylate. Carboxyl group-containing vinyl monomers such as crotonic acid, fumaric acid, maleic acid, itaconic acid, citraconic acid, monomethyl maleate, monoethyl maleate, monooctyl maleate, monomethyl itaconate, monoethyl itaconate, monobutyl itaconate, monooctyl itaconate, monomethyl fumarate, monoethyl fumarate, monobutyl fumarate, monooctyl fumarate, and monoethyl citraconic acid.

[0076] Vinyl monomers containing an acid anhydride group such as maleic anhydride and itaconic anhydride. Unsaturated dicarboxylic acid diester monomers such as dimethyl maleate, dibutyl maleate, dimethyl fumarate, dibutyl fumarate, butyl itaconate, and diperfluorocyclohexyl fumarate. Epoxy group-containing vinyl monomers such as glycidyl (meth)acrylate, α-ethyl glycidyl acrylate, and 3,4-epoxybutyl (meth)acrylate. Amino group-containing (meth)acrylic acid ester vinyl monomers such as dimethylaminoethyl (meth)acrylate and diethylaminoethyl (meth)acrylate.

[0077] Vinyl monomers containing an amide group, such as (meth)acrylamide, dimethyl(meth)acrylamide, diethyl(meth)acrylamide, N-tert-butyl(meth)acrylamide, N-methylol(meth)acrylamide, N-isopropylacrylamide, hydroxyethylacrylamide, N-methoxymethyl(meth)acrylamide, N-butoxymethyl(meth)acrylamide, diacetone acrylamide, maleic acid amide, and maleimide.

[0078] Vinyl monomers such as styrene, α-methylstyrene, vinyltoluene, (meth)acrylonitrile, vinyl chloride, vinyl acetate, and vinyl propionate. Polyfunctional vinyl monomers such as divinylbenzene, ethylene glycol di(meth)acrylate, 1,3-butylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol diallyl ether, and N,N'-methylenebis(meth)acrylamide. Heterocyclic monomers such as (meth)acryloylmorpholine, vinylpyrrolidone, vinylpyridine, and vinylcarbazole.

[0079] Polyethylene glycol (meth)acrylate, polypropylene glycol (meth)acrylate, methoxyethyl (meth)acrylate, ethoxyethyl (meth)acrylate, n-butoxyethyl (meth)acrylate, isobutoxyethyl (meth)acrylate, t-butoxyethyl (meth)acrylate, ethoxyethoxyethyl (meth)acrylate, phenoxyethyl (meth)acrylate, nonylphenoxyethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, acetoxyethyl (meth)acrylate, "Placcel FM" (trade name of caprolactone addition monomer manufactured by Daicel Chemical Industries, Ltd.), "Blemmer PME-100" (trade name of methoxypolyethylene glycol methacrylate (ethylene glycol chain length: 2) manufactured by NOF Corporation), "Blemmer PME-200" (trade name of methoxypolyethylene glycol methacrylate manufactured by NOF Corporation) glycol ester monomers such as acrylate (having four ethylene glycol chains), trade name), "BLEMMER PME-400" (NOF Corporation, methoxypolyethylene glycol methacrylate (having nine ethylene glycol chains), trade name), "BLEMMER 50POEP-800B" (NOF Corporation, octoxypolyethylene glycol-polypropylene glycol-methacrylate (having eight ethylene glycol chains and six propylene glycol chains), trade name), "BLEMMER 20ANEP-600" (NOF Corporation, nonylphenoxy (ethylene glycol-polypropylene glycol) monoacrylate, trade name), "BLEMMER AME-100" (NOF Corporation, trade name), "BLEMMER AME-200" (NOF Corporation, trade name), and "BLEMMER 50AOEP-800B" (NOF Corporation, trade name). Monomers containing silane coupling agents such as 3-(meth)acryloxypropyltrimethoxysilane, 3-(meth)acryloxypropylmethyldiethoxysilane, 3-(meth)acryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, vinyltrimethoxysilane, and vinyltriethoxysilane. Trimethylsilyl (meth)acrylate, triethylsilyl (meth)acrylate, tri-n-propylsilyl (meth)acrylate, tri-n-butylsilyl (meth)acrylate, tri-n-amylsilyl (meth)acrylate, tri-n-hexylsilyl (meth)acrylate, tri-n-octylsilyl (meth)acrylate, tri-n-dodecylsilyl (meth)acrylate, triisopropylsilylmethyl fumarate, triisopropylsilylamyl fumarate, tri-n-butylsilyl-n-butylfumarate, tert-butyldiphenylsilylmethyl fumarate, tert-butyldiphenylsilyl-n-butylfumarate, Silaprene FM- Organosilyl group-containing monomers other than silane coupling agent-containing monomers, such as 0711 (manufactured by JNC Corporation, trade name), Silaplane FM-0721 (manufactured by JNC Corporation, trade name), Silaplane FM-0725 (manufactured by JNC Corporation, trade name), Silaplane TM-0701 (manufactured by JNC Corporation, trade name), Silaplane TM-0701T (manufactured by JNC Corporation, trade name), X-22-174ASX (manufactured by Shin-Etsu Chemical Co., Ltd., trade name), X-22-174BX (manufactured by Shin-Etsu Chemical Co., Ltd., trade name), KF-2012 (manufactured by Shin-Etsu Chemical Co., Ltd., trade name), X-22-2426 (manufactured by Shin-Etsu Chemical Co., Ltd., trade name), and X-22-2404 (manufactured by Shin-Etsu Chemical Co., Ltd., trade name).

[0080] Halogenated olefins such as vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride, and chlorotrifluoroethylene. 2-Isocyanatoethyl (meth)acrylate. 2,2,2-trifluoroethyl (meth)acrylate, 2,2,3,3,3-pentafluorophenyl (meth)acrylate, 2-(perfluorobutyl)ethyl (meth)acrylate, 3-(perfluorobutyl)-2-hydroxypropyl (meth)acrylate, 2-(perfluorohexyl)ethyl (meth)acrylate, 3-perfluorohexyl-2-hydroxypropyl (meth)acrylate, 3-(perfluoro-3-methylbutyl)-2-hydroxypropyl Fluorine-containing monomers (excluding halogenated olefins), such as 2,2,3,3-tetrafluoropropyl (meth)acrylate, 1H,1H,5H-octafluoropentyl (meth)acrylate, 1H,1H,5H-octafluoropentyl (meth)methacrylate, 1H,1H,2H,2H-tridecafluorooctyl (meth)acrylate, and 1H-1-(trifluoromethyl)trifluoroethyl (meth)acrylate. Monomers with an acetal structure such as 1-butoxyethyl (meth)acrylate, 1-(2-ethylhexyloxy)ethyl (meth)acrylate, 1-(cyclohexyloxy)ethyl methacrylate, and 2-tetrahydropyranyl (meth)acrylate. 4-Methacryloyloxybenzophenone, and 2-isocyanatoethyl (meth)acrylate.

[0081] The monomer (b1) is preferably at least one selected from the group consisting of the following monomers, from the viewpoint of ease of handling. Hydrocarbon group-containing (meth)acrylic acid esters such as methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, isooctyl (meth)acrylate, nonyl (meth)acrylate, isononyl (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, lauryl (meth)acrylate, hexadecyl (meth)acrylate, stearyl (meth)acrylate, isostearyl (meth)acrylate, phenyl (meth)acrylate, benzyl (meth)acrylate, cyclohexyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, isobornyl (meth)acrylate, and terpene acrylates and derivatives thereof.

[0082] Hydroxyl group-containing (meth)acrylic acid esters such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate. Carboxyl group-containing vinyl monomers such as (meth)acrylic acid. Epoxy group-containing vinyl monomers such as glycidyl (meth)acrylate and glycidyl α-ethylacrylate. Amino group-containing (meth)acrylic acid ester vinyl monomers such as dimethylaminoethyl (meth)acrylate and diethylaminoethyl (meth)acrylate.

[0083] Vinyl monomers containing an amide group, such as (meth)acrylamide, N-methyl(meth)acrylamide, N,N'-dimethyl(meth)acrylamide, N-isopropylacrylamide, and N-(hydroxymethyl)acrylamide. Polyfunctional vinyl monomers such as ethylene glycol di(meth)acrylate, 1,3-butylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, pentaerythritol tetra(meth)acrylate, allyl (meth)acrylate, and N,N'-methylenebis(meth)acrylamide.

[0084] Heterocyclic monomers such as (meth)acryloylmorpholine, vinylpyrrolidone, vinylpyridine, and vinylcarbazole. Monomers containing silane coupling agents such as 3-(meth)acryloxypropyltrimethoxysilane, 3-(meth)acryloxypropylmethyldiethoxysilane, 3-(meth)acryloxypropyltriethoxysilane, and 3-acryloxypropyltrimethoxysilane. Organosilyl group-containing monomers other than silane coupling agent-containing monomers, such as trimethylsilyl (meth)acrylate, triethylsilyl (meth)acrylate, tri-n-propylsilyl (meth)acrylate, and tri-n-butylsilyl (meth)acrylate.

[0085] Fluorine-containing monomers such as 2,2,2-trifluoroethyl (meth)acrylate and 2,2,3,3-tetrafluoropropyl (meth)acrylate (however, halogenated olefins are excluded). Monomers with an acetal structure such as 1-butoxyethyl (meth)acrylate and 1-(2-ethylhexyloxy)ethyl (meth)acrylate.

[0086] The lower limit of the weight-average molecular weight of the (meth)acrylic polymer (B) is not particularly limited, but is preferably at least 50,000, more preferably at least 60,000, even more preferably at least 70,000, and particularly preferably at least 80,000. If the weight-average molecular weight of the (meth)acrylic polymer (B) is at least 50,000, the particles of the present invention will have good powder flowability and blocking resistance, which is preferable. The upper limit of the weight-average molecular weight of the (meth)acrylic polymer (B) is not particularly limited, but is preferably not more than 5,000,000, more preferably not more than 4,000,000, even more preferably not more than 3,000,000, and particularly preferably not more than 2,000,000. When the weight-average molecular weight of the (meth)acrylic polymer (B) is 5,000,000 or less, the melt moldability of the particles of the present invention can be maintained good, the moldability of a molding material containing the particles of the present invention is improved, and the appearance of the obtained molded product is excellent.

[0087] The lower limit of the glass transition temperature (Tg) of the (meth)acrylic polymer (B) is 40° C. or higher, preferably 45° C. or higher, and more preferably 50° C. or higher. When the (meth)acrylic polymer (B) has a Tg of 40° C. or higher, the powder fluidity of the particles containing the (meth)acrylic copolymer (A) can be further improved, and the blocking resistance can also be further improved. The upper limit of the glass transition temperature (Tg) of the (meth)acrylic polymer (B) is not more than 80° C., preferably not more than 75° C., and more preferably not more than 70° C. When the Tg of the (meth)acrylic copolymer B is not more than 80° C., the (meth)acrylic polymer (B) can efficiently coat the surface of the (meth)acrylic copolymer (A), resulting in better powder flowability of the particles.

[0088] The particle size of the (meth)acrylic polymer (B) is preferably 20 μm or less, more preferably 10 μm or less, even more preferably 5 μm or less, and particularly preferably 1 μm or less, as a volume-based median diameter measured using a particle size distribution analyzer. The particle size of the (meth)acrylic polymer (B) is preferably 1 nm or more, more preferably 10 nm or more, even more preferably 50 nm or more, and particularly preferably 100 nm or more, as a volume-based median diameter measured using a particle size distribution analyzer. A particle size of the (meth)acrylic polymer (B) of 20 μm or less is preferred because it allows the (meth)acrylic polymer (B) to efficiently coat the (meth)acrylic copolymer (A). A particle size of the (meth)acrylic polymer (B) of 1 nm or more is preferred because it provides better blocking resistance. As mentioned above, the median diameter refers to the diameter value at which, when a powder is divided into two particles at a certain particle size, the larger and smaller particles are equal in amount.

[0089] The (meth)acrylic polymer (B) can be used either individually or in combination of two or more.

[0090] In the particles of the present invention, the content of the (meth)acrylic polymer (B) is not particularly limited, but is preferably 20 parts by mass or less, more preferably 10 parts by mass or less, even more preferably 7 parts by mass or less, and particularly preferably 5 parts by mass or less, relative to 100 parts by mass of the (meth)acrylic copolymer (A). It is preferable that the content of the (meth)acrylic polymer (B) is 20 parts by mass or less, relative to 100 parts by mass of the (meth)acrylic copolymer (A), because the inherent performance of the (meth)acrylic copolymer (A) is not impaired. Furthermore, the content of the (meth)acrylic polymer (B) in the particles of the present invention is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, even more preferably 0.1 parts by mass or more, and particularly preferably 0.5 parts by mass or more, relative to 100 parts by mass of the (meth)acrylic copolymer (A). When the content of the (meth)acrylic polymer (B) is 0.01 parts by mass or more relative to 100 parts by mass of the total of the (meth)acrylic copolymer (A), the powder fluidity of the particles of the present invention can be further improved, and the blocking resistance is more excellent, which is preferable.

[0091] [Particle manufacturing method] The particles of the present invention are preferably produced by suspension polymerization, from the viewpoints that the heat generated by polymerization can be easily controlled and impurities can be removed by washing the particles.

[0092] The particles of the present invention can be produced, for example, by the following method for producing a (meth)acrylic copolymer (A), and a method including a step of heating a mixture of the (meth)acrylic copolymer (A) and a (meth)acrylic polymer (B) at a temperature equal to or higher than the glass transition temperature (Tg) of the (meth)acrylic polymer (B). The form of the (meth)acrylic polymer (B) is not particularly limited, and may be, for example, a powder, an aqueous suspension, or an emulsion, with an emulsion being preferred.

[0093] The particles of the present invention preferably have obtaining a suspension containing the (meth)acrylic copolymer (A) by suspension polymerization; obtaining an emulsion containing the (meth)acrylic polymer (B) by emulsion polymerization; a step of mixing the suspension and the emulsion and heat-treating the mixture at a temperature equal to or higher than the glass transition temperature (Tg) of the (meth)acrylic copolymer (B); The particles are produced by the method for producing particles of the present invention, which comprises:

[0094] The heating temperature of the mixture of the (meth)acrylic copolymer (A) and the (meth)acrylic polymer (B) when producing the particles of the present invention is preferably 60° C. or higher, more preferably 70° C. or higher, and even more preferably 80° C. or higher. A heating temperature of 60° C. or higher is preferred because the powder fluidity of the resulting particles is even better.

[0095] When heating a mixture of the (meth)acrylic copolymer (A) and the (meth)acrylic polymer (B), if the (meth)acrylic polymer (B) is an emulsion, a coagulant may be used to promote coagulation. The coagulant is not particularly limited, but examples include inorganic acids such as sulfuric acid, hydrochloric acid, phosphoric acid, and nitric acid; organic acids such as acetic acid; and salts of inorganic and organic acids with sodium, potassium, calcium, magnesium, and aluminum. These coagulants can be used alone or in combination of two or more.

[0096] [Method for producing (meth)acrylic copolymer (A)] The block copolymer and / or graft copolymer that is the (meth)acrylic copolymer (A) according to the present invention can be produced by a living polymerization method or a method using a macromonomer (a1) described below.

[0097] Examples of living polymerization methods include living radical polymerization and living anionic polymerization. Examples of living radical polymerization methods include reversible addition-fragmentation chain transfer polymerization (RAFT), atom transfer radical polymerization (ATRP), nitroxide-mediated polymerization (NMP), and organotellurium-based living radical polymerization (TERP). The method using macromonomer (a1) is advantageous in that it allows for relatively easy production of block copolymers and / or graft copolymers (A), and is preferred because it does not require the steps of removing catalyst and auxiliary residues or terminal treatment, which are required in living polymerization methods.

[0098] [Method for producing (meth)acrylic copolymer (A) using macromonomer] In a method for producing the (meth)acrylic copolymer (A) using a macromonomer, the macromonomer may be used as a raw material for either the polymer (A1) or the (meth)acrylic polymer (A2). The macromonomer may be copolymerized with a comonomer copolymerizable with the macromonomer to obtain a macromonomer copolymer, which may then be used as the (meth)acrylic copolymer (A). Here, as an example, a method for producing a macromonomer copolymer by copolymerizing a macromonomer (a1) described below as a raw material for a polymer (A1) with the above-mentioned monomer (a2) will be described. In this case, the (meth)acrylic polymer (A2) has the monomer (a2) as a monomer unit.

[0099] [Method for producing macromonomer (a1)] The macromonomer (a1) can be produced by a known method. Examples of methods for producing the macromonomer include a method using a cobalt chain transfer agent (U.S. Patent No. 4,680,352), a method using an α-substituted unsaturated compound such as α-bromomethylstyrene as a chain transfer agent (WO 88 / 04304), a method of chemically bonding a polymerizable group (JP-A-60-133007, U.S. Patent No. 5,147,952, and JP-A-06-298921), and a method using thermal decomposition (JP-A-11-240854). Among these, the method for producing the macromonomer (a1) using a cobalt chain transfer agent is preferred because it requires fewer production steps and uses a catalyst with a high chain transfer constant.

[0100] Examples of methods for producing the macromonomer (a1) using a cobalt chain transfer agent include bulk polymerization, solution polymerization, and aqueous dispersion polymerization methods such as suspension polymerization, emulsion polymerization, etc. Among these, the aqueous dispersion polymerization method is preferred from the viewpoint of simplifying the recovery process of the macromonomer (a1).

[0101] The cobalt chain transfer agent used in the present invention may be a cobalt chain transfer agent represented by the following general formula (2):

[0102] [ka]

[0103] [In the formula, R 11 ~R 14 are each independently an alkyl group, a cycloalkyl group, or an aryl group. 11 ~X 14 are each independently an F atom, a Cl atom, a Br atom, an OH group, an alkoxy group, an aryloxy group, an alkyl group, or an aryl group.

[0104] Specific examples of cobalt chain transfer agents include bis(borondifluorodimethyldioximinocyclohexane)cobalt(II), bis(borondifluorodimethylglyoximate)cobalt(II), bis(borondifluorodiphenylglyoximate)cobalt(II), cobalt(II) complexes of vicinaliminohydroxyimino compounds, cobalt(II) complexes of tetraazatetraalkylcyclotetradecatetraenes, N,N'-bis(salicylidene)ethylenediaminocobalt(II) complexes, cobalt(II) complexes of dialkyldiazadioxodialkyldodecadienes, and cobalt(II) porphyrin complexes. Among these, bis(borondifluorodiphenylglyoximate)cobalt(II)(R 11 ~R 14 : phenyl group, X 11 ~X 14 : F atom) are preferred. One or more of these can be appropriately selected and used.

[0105] The amount of the cobalt chain transfer agent used is preferably 5 ppm to 350 ppm relative to 100 parts by mass of the monomer for obtaining macromonomer (a1). If the amount of the cobalt chain transfer agent used is 5 ppm or more, the molecular weight is likely to be sufficiently reduced, and if it is 350 ppm or less, the obtained macromonomer (a1) is less likely to be discolored.

[0106] Examples of solvents used when obtaining macromonomer (a1) by solution polymerization include hydrocarbons such as toluene, ethers such as diethyl ether and tetrahydrofuran, halogenated hydrocarbons such as dichloromethane and chloroform, ketones such as acetone, alcohols such as methanol, nitriles such as acetonitrile, vinyl esters such as ethyl acetate, carbonates such as ethylene carbonate, and supercritical carbon dioxide. These can be used alone or in combination of two or more.

[0107] [Method of manufacturing macromonomer copolymer] The method for producing the macromonomer copolymer includes a step of polymerizing a polymerizable mixture containing the polymerizable composition (X) and a polymerization initiator, which will be described later. In one embodiment for producing the particles of the present invention, in the polymerization reaction step, the polymerizable mixture containing the polymerizable composition (X) and the polymerization initiator is used to polymerize the polymerizable composition (X).

[0108] The polymerizable composition (X) contains a macromonomer (a1) and a comonomer copolymerizable with the macromonomer (a1). The comonomer is appropriately selected from the monomers (a2) that are copolymerizable with the macromonomer (a1). In the present invention, it is particularly preferable to use the macromonomer (a1) represented by the following general formula (1), from the viewpoint of improving the moldability of the molding material containing the particles of the present invention.

[0109] [ka]

[0110] (In formula (1), R 0 ~R n are each independently a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or a heterocyclic group. 1 ~X n are each independently a hydrogen atom or a methyl group. Z is a terminal group. n is a natural number from 1 to 10,000.

[0111] <R0 ~R n > In the formula (1), R 0 ~R n The alkyl group, cycloalkyl group, aryl group or heterocyclic group may have a substituent.

[0112] R 0 ~R n Examples of the alkyl group include branched or linear alkyl groups having 1 to 20 carbon atoms. Specific examples include methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, t-butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, and icosyl. Among these, in terms of availability, methyl, ethyl, n-propyl, i-propyl, n-butyl, t-butyl, pentyl, hexyl, heptyl, and octyl are preferred, with methyl, ethyl, n-propyl, i-propyl, n-butyl, and t-butyl being more preferred, and methyl being particularly preferred.

[0113] R 0 ~R n Examples of the cycloalkyl group include cycloalkyl groups having 3 to 20 carbon atoms. Specific examples include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a t-butylcyclohexyl group, an isobornyl group, an adamantyl group, etc. In view of availability, a cyclopropyl group, a cyclobutyl group, and an adamantyl group are preferred.

[0114] R 0 ~R n The aryl group may be, for example, an aryl group having a carbon number of 6 to 18. Specific examples include a phenyl group, a benzyl group, and a naphthyl group.

[0115] R 0 ~Rn Examples of the heterocyclic group include heterocyclic groups having 5 to 18 carbon atoms. Specific examples include a γ-lactone group, an ε-caprolactone group, a morpholine group, etc. Examples of heteroatoms contained in the heterocycle include an oxygen atom, a nitrogen atom, a sulfur atom, etc.

[0116] R 0 ~R n The substituents of each independently include a group or atom selected from the group consisting of an alkyl group, an aryl group, a carboxy group, an alkoxycarbonyl group (-COOR'), a carbamoyl group (-CONR'R''), a cyano group, a hydroxy group, an amino group, an amide group (-NR'R''), a halogen atom, an allyl group, an epoxy group, an alkoxy group (-OR'), and a group exhibiting hydrophilicity or ionicity. Examples of R' or R'' each independently include R 0 ~R n and the like (excluding heterocyclic groups).

[0117] R 0 ~R n Examples of the alkoxycarbonyl group as a substituent of include a methoxycarbonyl group. R 0 ~R n Examples of the carbamoyl group as a substituent of include an N-methylcarbamoyl group and an N,N-dimethylcarbamoyl group. R 0 ~R n The amide group as the substituent of the formula (I) may be, for example, a dimethylamide group. R 0 ~R n Examples of the halogen atom as a substituent of include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R 0 ~R n Examples of the alkoxy group as the substituent include an alkoxy group having 1 to 12 carbon atoms. A specific example is a methoxy group. R 0 ~R nExamples of the hydrophilic or ionic group as a substituent include an alkali salt of a carboxy group or an alkali salt of a sulfoxyl group, a poly(alkylene oxide) group such as a polyethylene oxide group or a polypropylene oxide group, and a cationic substituent such as a quaternary ammonium base.

[0118] R 0 ~R n is preferably at least one selected from an alkyl group and a cycloalkyl group, and more preferably an alkyl group. The alkyl group is preferably a methyl group, an ethyl group, an n-propyl group, or an i-propyl group, and from the viewpoint of availability, a methyl group is more preferred.

[0119] <X 1 ~X n > In the formula (1), X 1 ~X n From the viewpoint of ease of synthesis of the macromonomer (a1), X 1 ~X n Preferably, 80 mol % or more of the total number of moles (100 mol %) of the groups are methyl groups.

[0120] <z> In the formula (1), Z is a terminal group of the macromonomer (a1). Examples of the terminal group of the macromonomer (a1) include a hydrogen atom and a group derived from a radical polymerization initiator, similar to terminal groups of polymers obtained by known radical polymerization.

[0121] The lower limit of the content of methyl methacrylate units in the macromonomer (a1) is not particularly limited, and a content of 50% by mass or more relative to 100% by mass of the total mass of the macromonomer (a1) is advantageous for improving impact resistance and transparency. The lower limit of the content of methyl methacrylate units is preferably 50% by mass or more, more preferably 80% by mass or more, even more preferably 90% by mass or more, and particularly preferably 95% by mass or more. On the other hand, the upper limit of the content of methyl methacrylate units is not particularly limited, and may be 100% by mass of methyl methacrylate units, or may be 99% by mass or less relative to 100% by mass of the total mass of the macromonomer (a1).

[0122] In the method for producing the macromonomer copolymer, the polymerization reaction is preferably carried out by radical polymerization.

[0123] In the method for producing a macromonomer copolymer according to the present invention, the upper limit of the content of the sulfur-containing chain transfer agent contained in the polymerizable mixture is preferably less than 0.01 parts by mass relative to 100 parts by mass of the polymerizable composition (X). If the upper limit of the content of the sulfur-containing chain transfer agent is less than 0.01 parts by mass, the composition distribution of the copolymer can be prevented from becoming broad, thereby improving the impact resistance of the resulting molded article. The lower limit of the content of the sulfur-containing chain transfer agent is not particularly limited, and it is more preferable that no sulfur-containing chain transfer agent is contained. The sulfur-containing chain transfer agent refers to a mercaptan compound such as n-butyl mercaptan or n-octyl mercaptan, which is added as a chain transfer agent to adjust the molecular weight of the copolymer during polymerization.

[0124] Furthermore, in the production of the macromonomer copolymer, polymerization can be carried out so that the weight-average molecular weight (Mw) of the resulting macromonomer copolymer is 50,000 or more and 2,500,000 or less. The lower limit of the weight-average molecular weight (Mw) of the macromonomer copolymer is preferably 50,000 or more, more preferably 100,000 or more, even more preferably 300,000 or more, and particularly preferably 600,000 or more. On the other hand, the upper limit of the Mw of the macromonomer polymer is preferably 2,500,000 or less, more preferably 2,000,000 or less, and even more preferably 1,500,000 or less. When the weight-average molecular weight (Mw) of the macromonomer copolymer is 50,000 or more, the macromonomer copolymer is more likely to exhibit its inherent properties, such as heat resistance, hardness, scratch resistance, weather resistance, and transparency. When the weight-average molecular weight (Mw) of the macromonomer copolymer is 2,500,000 or less, the melt viscosity falls within an appropriate range, resulting in good melt-kneadability and processability. The above upper and lower limits can be combined arbitrarily. The method for controlling the weight average molecular weight (Mw) of the macromonomer copolymer within the above range is not particularly limited, and can be controlled by adjusting the polymerization method, the type and amount of polymerization initiator, the amount of chain transfer agent, the polymerization temperature, etc., according to well-known techniques.

[0125] [Polymerizable composition (X)] The polymerizable composition (X) is one of the raw materials for the (meth)acrylic copolymer (A). The content ratios of the macromonomer (a1) (a1, unit: mass%) and the monomer (a2) (a2, unit: mass%) contained in the polymerizable composition (X), relative to 100 mass% of the total mass of the polymerizable composition (X), are preferably a1:a2=35-75% by mass:65-25% by mass, more preferably a1:a2=40-70% by mass:60-30% by mass, even more preferably a1:a2=45-70% by mass:55-30% by mass, particularly preferably a1:a2=50-65% by mass:50-35% by mass, and most preferably a1:a2=55-65% by mass:45-35% by mass. The ratio of the macromonomer (a1) (a1, unit: mass%) to the monomer (a2) (a2, unit: mass%) contained in the polymerizable composition (X), relative to 100% by mass of the total mass of the polymerizable composition (X), is preferably 35:65 to 75:25, more preferably 40:60 to 70:30, even more preferably 45:55 to 70:30, particularly preferably 50:50 to 65:35, and most preferably 55:45 to 65:35. When the lower limit of the macromonomer (a1) content in the polymerizable composition (X) is 35% by mass or more, or when the upper limit of the monomer (a2) content is 65% by mass or less, relative to 100% by mass of the total mass of the polymerizable composition (X), the macromonomer copolymer becomes easy to handle. Furthermore, when the lower limit of the content of the monomer (a2) contained in the polymerizable composition (X) is 25 mass% or more, or the upper limit of the content of the macromonomer (a1) is 75 mass% or less, relative to 100 mass% of the total mass of the polymerizable composition (X), the impact resistance of the molding material containing the macromonomer copolymer and the obtained molded article can be maintained well.

[0126] For ease of explanation, the polymerizable composition (X) containing the macromonomer (a1) and the monomer (a2) is referred to as the "polymerizable composition (X)." However, it is not necessary to prepare the polymerizable composition (X) by previously mixing the macromonomer (a1) and the monomer (a2). It is sufficient that the polymerizable composition (X) is in a state in which the macromonomer (a1) and the monomer (a2) coexist in the polymerization step.

[0127] [Production of macromonomer copolymers by suspension polymerization] The case where the polymerization reaction is carried out by suspension polymerization will be described in detail below as one embodiment of the present invention. In the method for producing a macromonomer copolymer, when the macromonomer copolymer is produced by suspension polymerization, examples include a method in which the production of the macromonomer (a1) of the present invention and the production of the macromonomer copolymer are carried out separately, which include the following steps i) to iv), and a method in which the production of the macromonomer (a1) of the present invention and the production of the macromonomer copolymer of the present invention are carried out continuously, which includes the following steps I) to II) instead of the following steps i) to ii) among the following steps i) to v).

[0128] i) Syrup preparation process A bead-like macromonomer (a1) produced by suspension polymerization is dissolved in a solution containing a monomer (a2) to prepare a syrup, which is designated as a polymerizable composition (X). When preparing the polymerizable composition (X), a mixture containing the macromonomer (a1) and the monomer (a2) can be heated at a temperature equal to or lower than the boiling point of the monomer (a2) to promote dissolution of the macromonomer (a1). The temperature at which the polymerizable composition (X) is prepared is preferably in the range of 20°C to 100°C, more preferably in the range of 40°C to 80°C. If the radical polymerization initiator used does not react at the temperature at which the polymerizable composition (X) is prepared, the radical polymerization initiator can be mixed with the polymerizable composition (X) to obtain a polymerizable mixture, and then the polymerizable mixture can be heated.

[0129] ii) Radical polymerization initiator dissolution step When the radical polymerization initiator reacts at the temperature at which the polymerizable composition (X) obtained in step i) is prepared, the polymerizable composition (X) is first cooled to room temperature or below, and then the radical polymerization initiator is added and dissolved uniformly to obtain a polymerizable mixture. The temperature of the polymerizable composition (X) when the radical polymerization initiator is added is preferably set to a temperature equal to or lower than the 10-hour half-life temperature of the radical polymerization initiator minus 15°C.

[0130] iii) Preparation of aqueous solution The polymerizable mixture and the aqueous solution are mixed and then stirred to prepare a suspension in which droplets of the polymerizable mixture are dispersed in the aqueous solution. The aqueous solution is an aqueous solution for dispersing the polymerizable mixture, and may contain a dispersant, an electrolyte, and other auxiliary agents. By appropriately selecting the combination of the dispersant and the electrolyte, the dispersibility of the droplets of the polymerizable mixture formed in the aqueous solution when the polymerizable mixture is dispersed in the aqueous solution can be controlled. The water used in the aqueous solution is preferably deionized water, since this improves the dispersibility of the droplets of the polymerizable mixture.

[0131] Examples of dispersants include alkali metal salts of poly(meth)acrylic acid, copolymers of alkali metal salts of (meth)acrylic acid and (meth)acrylic acid esters, copolymers of alkali metal salts of sulfoalkyl (meth)acrylate and (meth)acrylic acid esters, alkali metal salts of polystyrene sulfonates, copolymers of alkali metal salts of styrene sulfonates and (meth)acrylic acid esters, or copolymers of combinations of these monomers; polyvinyl alcohol with a saponification degree of 70 to 100%, methyl cellulose, starch, and hydroxyapatite. These can be used alone or in combination of two or more. Among these, copolymers of alkali metal salts of sulfoalkyl (meth)acrylate and (meth)acrylic acid esters and copolymers of alkali metal salts of (meth)acrylic acid and (meth)acrylic acid esters are preferred, as they exhibit good dispersion stability during suspension polymerization. The amount of dispersant added is, for example, in the range of 0.0005 to 0.5 parts by mass per 100 parts by mass of the polymerizable composition (X). Examples of the electrolyte include sodium carbonate, sodium sulfate, manganese sulfate, etc. The amount of the electrolyte added is, for example, in the range of 0.01 to 1.0 part by mass relative to 100 parts by mass of the polymerizable composition (X).

[0132] I) Syrup preparation process The polymerizable composition (X) is prepared by adding a solution containing a monomer (a2) to a bead-like macromonomer (a1) produced by suspension polymerization dispersed in an aqueous solution. The temperature at which the macromonomer (a1) is dissolved in the solution containing the monomer (a2) is preferably in the range of 20°C to 100°C, more preferably in the range of 40°C to 90°C, and even more preferably in the range of 50°C to 80°C.

[0133] II) Radical polymerization initiator dissolution process When the radical polymerization initiator reacts at the temperature at which the polymerizable composition (X) obtained in step I) is prepared, the polymerizable composition (X) is first cooled to room temperature or below, and then the radical polymerization initiator is added and dissolved uniformly to obtain a polymerizable mixture. The temperature of the polymerizable composition (X) when the radical polymerization initiator is added is preferably set to a temperature equal to or lower than the 10-hour half-life temperature of the radical polymerization initiator minus 15°C.

[0134] When the polymerization reaction is carried out in the presence of a radical polymerization initiator, known organic peroxides such as 2,4-dichlorobenzoyl peroxide and t-butyl peroxypivalate, and known azo compounds such as 2,2'-azobisisobutyronitrile and 2,2'-azobis(2,4-dimethylvaleronitrile) can be used as the radical polymerization initiator. The amount of the radical polymerization initiator to be added can be appropriately selected by a person skilled in the art according to well-known techniques. The usual amount of the radical polymerization initiator to be added is 0.0001 to 10 parts by mass per 100 parts by mass of the total amount of the polymerizable composition (X).

[0135] iv) Polymerization reaction step The resulting suspension is then heated while being stirred to initiate the polymerization reaction. It is preferable to remove dissolved oxygen from the polymerizable mixture and the aqueous solution before heating by subjecting them to vacuum degassing or nitrogen substitution. The polymerization temperature during the polymerization reaction is an important condition for obtaining a macromonomer copolymer in a high yield. The polymerization temperature here refers to the temperature of the suspension. The polymerization temperature is preferably 50°C to 90°C, more preferably 60°C to 85°C, and even more preferably 65°C to 80°C. If the polymerization temperature is too low, the reaction may proceed slowly, resulting in a long polymerization time. Furthermore, if the polymerization temperature is too high, cleavage of the adduct radical, which is a reaction intermediate, takes precedence, tending to reduce the yield of the macromonomer copolymer. In the latter stage of the polymerization reaction, the suspension can be heated to increase the reaction rate of the polymerizable composition (X) and to eliminate unreacted radical polymerization initiator. The temperature to which the suspension is heated is preferably 80°C or higher, more preferably 85°C or higher. The temperature rise time can be determined by calculating the time required for the radical polymerization initiator to disappear, and is usually about 30 minutes to 2 hours.

[0136] v) Recovery process After the above process, the suspension is cooled to room temperature or below, and the resulting copolymer in the form of beads is recovered by a known method such as filtration. This recovery process preferably includes a bead surface treatment process, which will be described later. If necessary, a washing process for removing impurities such as dispersants and electrolytes, a process for removing beads containing air bubbles, a drying process, etc. may be performed.

[0137] [Method for producing (meth)acrylic polymer (B)] The (meth)acrylic polymer (B) is produced using the monomer (b1) as a raw material. The (meth)acrylic polymer (B) is preferably produced by emulsion polymerization. By using the emulsion polymerization method, an emulsion containing the (meth)acrylic polymer (B) is obtained. By containing the (meth)acrylic polymer (B) as an emulsion, it is suitable for use in the surface treatment step of beads described below. When the (meth)acrylic polymer (B) is produced by emulsion polymerization, a commonly known initiator, monomer dropping method, stirring method, reaction vessel, etc. suitable for emulsion polymerization can be used. Known water-soluble initiators can be used as the initiator. Examples of initiators include redox initiators, azo initiators, and organic peroxide initiators.

[0138] [Surface treatment step of beads containing (meth)acrylic copolymer (A)] In the method for producing particles of the present invention, it is preferable to perform a surface treatment on beads containing the (meth)acrylic copolymer (A) using a suspension (slurry) containing the (meth)acrylic copolymer (A) and an emulsion containing the (meth)acrylic polymer (B).

[0139] [Suspension containing (meth)acrylic copolymer (A)] Here, the suspension containing the (meth)acrylic copolymer (A) is preferably obtained by suspension polymerization. The suspension containing the (meth)acrylic copolymer (A) can also be obtained by redispersing beads containing the (meth)acrylic copolymer (A) in an aqueous solution after washing and recovery. The emulsion containing the (meth)acrylic polymer (B) is preferably obtained by emulsion polymerization. In the surface treatment step of beads containing the (meth)acrylic copolymer (A), an emulsion containing the (meth)acrylic polymer (B) is added to a suspension containing the (meth)acrylic copolymer (A), and then the emulsion is solidified under certain conditions, thereby coating the surface of the beads containing the (meth)acrylic copolymer (A) with the (meth)acrylic polymer (B).

[0140] In the step of adding an emulsion containing a (meth)acrylic polymer (B) to a suspension containing a (meth)acrylic copolymer (A), specifically, the temperature of the emulsion is preferably 20°C or higher and 90°C or lower, more preferably 25°C or higher and 70°C or lower, and even more preferably 30°C or higher and 60°C or lower. By keeping the temperature of the suspension at 90°C or lower, it is possible to prevent rapid solidification of the (meth)acrylic polymer (B) when the emulsion containing the (meth)acrylic polymer (B) is added, which would otherwise result in a non-uniform processing state. Furthermore, if the temperature of the suspension is 20°C or higher, it is possible to keep the energy cost required for cooling the suspension low. Furthermore, when an emulsion of the (meth)acrylic polymer (B) is added to a suspension containing the (meth)acrylic copolymer (A), the temperature of the suspension is not particularly limited, but is preferably lower than the glass transition temperature (Tg) of the (meth)acrylic polymer (B). Having a temperature of the suspension lower than the Tg of the (meth)acrylic polymer (B) is preferred because it can prevent rapid solidification of the (meth)acrylic polymer (B) when the emulsion is added to the suspension, resulting in a non-uniform processing state.

[0141] [Coagulant] Various acids and salts can be used as the coagulant. Examples of the various acids and salts that can be used include inorganic acids such as sulfuric acid, hydrochloric acid, phosphoric acid, and nitric acid, organic acids such as acetic acid, and salts of inorganic and organic acids with sodium, potassium, calcium, magnesium, and aluminum. These coagulants can be used alone or in combination of two or more. These acids and salts are added to a suspension containing the (meth)acrylic copolymer (A) after preparing an appropriate aqueous solution. In the surface treatment process of beads containing a (meth)acrylic polymer (A), the timing of adding the coagulant can be selected appropriately. The coagulant may be added before adding an emulsion containing a (meth)acrylic polymer (B) to a suspension containing a (meth)acrylic polymer (A), or after adding an emulsion containing a (meth)acrylic polymer (B) to a suspension containing a (meth)acrylic copolymer (A). To prevent uneven coagulation of the (meth)acrylic polymer (B), it is preferable to add the coagulant before adding an emulsion containing a (meth)acrylic polymer (B) to a suspension containing a (meth)acrylic polymer (A).

[0142] [Heat treatment process] After the emulsion of the (meth)acrylic polymer (B) is added to the suspension containing the (meth)acrylic copolymer (A) and thoroughly mixed, the mixture of the suspension containing the (meth)acrylic copolymer (A) and the emulsion containing the (meth)acrylic polymer (B) is preferably heated to a temperature equal to or higher than the glass transition temperature (Tg) of the (meth)acrylic polymer (B). Heat treatment at a temperature equal to or higher than the Tg of the (meth)acrylic polymer (B) promotes coagulation of the (meth)acrylic polymer (B), allowing the surface of the beads containing the (meth)acrylic copolymer (A) to be coated with the (meth)acrylic polymer (B). The heat treatment temperature is preferably 60°C or higher and 100°C or lower, more preferably 70°C or higher and 90°C or lower. A heat treatment temperature of 60°C or higher is preferred because coagulation proceeds efficiently, while a heat treatment temperature of 100°C or lower can save energy during the heat treatment. The heat treatment temperature is preferably 5°C or higher, more preferably 10°C or higher, than the Tg of the (meth)acrylic polymer (B). When the temperature for the heat treatment is higher than the Tg of the (meth)acrylic polymer (B) by 5° C. or more, coagulation proceeds more efficiently. After the heat treatment is complete, the suspension is cooled, washed, and dried to obtain particles.

[0143] [Particle Uses] The particles of the present invention have excellent powder flowability and blocking resistance, making them suitable for use as raw materials for molding materials. Specifically, the excellent powder flowability and blocking resistance allow the particles to pass through the packaging process smoothly after washing and drying. Furthermore, fewer particles remain in pipes, hoppers, and drying ovens, reducing product loss and improving workability. Furthermore, in the manufacturing process of a molding material using the particles of the present invention, since the particles have high blocking resistance, problems due to blocking are unlikely to occur during mixing as a powder or during transportation and storage processes.

[0144] [Molding material] The molding material of the present invention contains the particles of the present invention as an essential component, and may consist solely of the particles of the present invention (here, "particles alone" means containing one or more types of particles of the present invention with different configurations), or may contain a matrix resin described below as necessary.

[0145] When the molding material of the present invention contains the particles of the present invention and a matrix resin, the content of the particles of the present invention in the molding material of the present invention is preferably 15 parts by mass or more, more preferably 20 parts by mass or more, and particularly preferably 25 parts by mass or more, per 100 parts by mass of the total of the particles of the present invention and the matrix resin. The content of the particles of the present invention in the molding material of the present invention is preferably 70 parts by mass or less, more preferably 65 parts by mass or less, and particularly preferably 60 parts by mass or less, per 100 parts by mass of the total of the particles of the present invention and the matrix resin. When the content of the particles of the present invention is equal to or greater than the above lower limit, the molded article obtained by containing the particles of the present invention is likely to exhibit the desired properties such as heat resistance, hardness, scratch resistance, weather resistance, and transparency. On the other hand, when the content of the particles of the present invention is equal to or less than the above upper limit, the inherent properties of the matrix resin can be fully exhibited. However, the molding material of the present invention may consist solely of the particles of the present invention.

[0146] [Matrix resin] The molding material of the present invention can contain a matrix resin as needed. For example, it is preferable that the molding material contains a matrix resin as one of its main components and is used in combination with the particles of the present invention. Furthermore, the matrix resin is preferably a thermoplastic resin. In this case, any general-purpose thermoplastic resin can be used as the matrix resin without any particular limitation. Examples of matrix resins include polymethyl methacrylate, polycarbonate, rigid polyvinyl chloride, flexible polyvinyl chloride, polyolefin, polyurethane, polyester, polystyrene, acrylonitrile-styrene copolymer (AS resin), acrylonitrile-butadiene-styrene copolymer (ABS resin), and methyl methacrylate-styrene copolymer (MS resin). Among these, at least one selected from the group consisting of polymethyl methacrylate, polycarbonate, polyvinyl chloride, polyolefin, polyurethane, and polyester is preferred. These matrix resins may be used alone or in combination.

[0147] Further, some matrix resins will be specifically described. Polymethyl methacrylate is a polymer containing 80% by mass or more of methyl methacrylate units, and is also called a methacrylic resin. Examples of polymethyl methacrylate include Acrypet, a product of Mitsubishi Chemical Corporation. Representative types of Acrypet include VH, MD, MF, VH5, TF8, TF9, VH6, VHM, VHS, SV, VH4, and TN100.

[0148] Polycarbonates include aromatic polycarbonates and aliphatic polycarbonates. Examples of aromatic polycarbonates include polycarbonates having a bisphenol-A skeleton. Examples of aliphatic polycarbonates include polycarbonates containing an isosorbide skeleton, such as Durabio (trade name, manufactured by Mitsubishi Chemical Corporation). Representative Durabio varieties include D7340R, D6350R, D5360R, and D5380R.

[0149] Polyvinyl chloride (PVC) includes rigid PVC and flexible PVC, and is a resin composition containing a reinforcing agent, a plasticizer, a stabilizer, and the like. Examples of PVC include products manufactured by Shin-Etsu Chemical Co., Ltd. under the series name Straight Polymer. Representative varieties of Shin-Etsu PVC Straight Polymer include, for example, TK-500, TK-600, TK-700, TK-800, TK-1000, TK-1300, and TK-1400. Examples of additives such as reinforcing agents and processing aids include products manufactured by Mitsubishi Chemical Corporation under the trade name Metablen. Representative varieties of Metablen suitable for PVC include, for example, P-type, L-1000, S-2001, W-300A, W-450A, W-377, C-223A, C-215A, C-201A, C-140A, F-410, and H-602. Examples of plasticizers include DOP, DINP, and TOTM from J-Plus Corporation, and DINCH from BASF. Examples of stabilizers include complex metal soap stabilizers such as Ba-Zn, Ca-Zn, Ba-Ca-Sn, Ca-Mg-Sn, Ca-Zn-Sn, Pb-Sn, and Pb-Ba-Ca. Examples of antioxidants include epoxy compounds such as epoxidized vegetable oils such as epoxidized soybean oil and epoxidized linseed oil.

[0150] [Additive (C)] Additive (C) can be added to the molding material of the present invention as needed. Various additives can be selected as additive (C). Examples of additive (C) include various stabilizers such as antioxidants, UV absorbers, and heat stabilizers; colorants such as inorganic pigments, organic pigments, and dyes; conductivity-imparting agents such as carbon black and ferrite; inorganic fillers; lubricants; mold release agents; plasticizers; organic peroxides; neutralizers; crosslinking agents; and reinforcing agents. When additive (C) is added, the proportion of additive (C) is preferably 20% by mass or less, more preferably 10% by mass or less, relative to 100% by mass of the molding material. By setting the proportion of additive (C) to 20% by mass or less, the original properties of the molding material are maintained.

[0151] [Method of manufacturing molding material] The method for producing the molding material of the present invention is not particularly limited, and a commonly used resin mixing method or melt-kneading method can be applied. For example, a resin composition can be produced by mixing and / or kneading the particles of the present invention with a matrix resin or the like, which is added as needed. Examples of resin mixing and / or melt-kneading methods include methods using a Henschel mixer, Banbury mixer, V-type mixer, ribbon blender, planetary mixer, super mixer, tumbler, single-screw extruder, twin-screw extruder, multi-screw extruder, co-kneader, planetary gear extruder, plasticator, roll kneader, etc. These manufacturing methods can be combined as appropriate. The resulting molding material is preferably in the form of pellets or beads.

[0152] [Molding material packaging method] The molding material of the present invention can be packaged in various ways to prevent the inclusion or adsorption of foreign matter, or the absorption of unnecessary gases. For example, various clean packaging methods can be used to prevent the inclusion of foreign matter. Various coatings can be applied to the packaging material to impart gas barrier properties.

[0153] <Molded body> The molded article of the present invention obtained by molding the molding material of the present invention containing the particles of the present invention may have, for example, a sheet, a film, a tube, or a three-dimensional shape. Furthermore, the surface of the molded article may be a mirror finish, or both or one side may be textured with a textured or matte finish. A protective film or separator may be attached to the surface of the molded article. Furthermore, various powders may be attached to the surface to achieve better blocking resistance.

[0154] <Method of manufacturing molded body> The method for producing the molded article of the present invention by molding the molding material is preferably a melt molding method, such as injection molding, compression molding, blow molding, extrusion molding, rotational molding, casting, and solvent casting. Among these, injection molding and extrusion molding are preferred from the viewpoint of productivity. The mold, resin temperature, molding conditions, etc. used when molding using the molding machine are not particularly limited.

[0155] When producing a molded body, it is preferable to pre-dry the molding material at an appropriate temperature and time to adjust the moisture content of the molding material to an appropriate range, as in the production of the molding material described above. By appropriately adjusting the temperature and time within a certain range, defects such as foaming and / or poor appearance that occur during melt molding can be suppressed, and thermal degradation of the molding material can be suppressed, thereby suppressing the causes of deterioration in the physical properties and / or coloration of the molded body.

[0156] <Processing using molded bodies> The molded article of the present invention can be bonded or welded to other parts, or can be bonded or fused to sheets, films, or tubes to produce various products. Methods for welding the molded article of the present invention using the molding material of the present invention include ultrasonic welding, vibration welding, high-frequency welding, hot plate welding, laser welding, and spin welding. The molded article can be bonded using various adhesives, such as epoxy resins, vinyl acetates, acrylic resins, phenolic resins, chloroprene rubbers, nitrile rubbers, silicone rubbers, styrene butadiene rubbers, and cyanoacrylates. Solvent bonding can also be used. Tape bonding, such as double-sided tape, can also be used. When bonding different materials together, it is possible to combine a plurality of bonding methods depending on the materials to be bonded. [Example]

[0157] The present invention will be explained in more detail below by way of examples and comparative examples, but the present invention is not limited to the following examples. In the following, "parts" means "parts by mass."

[0158] [Measurement and evaluation methods] The evaluations in the examples and comparative examples were carried out by the following methods.

[0159] <Measurement of weight average molecular weight (Mw) and number average molecular weight (Mn) of macromonomer (a1)> The weight-average molecular weight (Mw) and number-average molecular weight (Mn) of the macromonomer (a1) obtained in the examples and comparative examples were measured by gel permeation chromatography (GPC). 10 mg of the copolymer obtained was dissolved in 10 mL of tetrahydrofuran, and the solution was filtered through a 0.45 μm filter to prepare a sample for GPC measurement. A polymer measurement guard column (manufactured by Tosoh Corporation, product name: TSK-GUARD COLUMN SUPER HH) and two polymer measurement columns (manufactured by Tosoh Corporation, product name: TSK-GEL SUPER HM-H) were connected in series to a gel permeation chromatography measurement device (manufactured by Tosoh Corporation, model name: HLC-8320). A differential refractometer (RI) was used as the detector. Measurements were performed under the following conditions: separation column temperature: 40°C, mobile phase: tetrahydrofuran, mobile phase flow rate: 0.6 mL / min, and sample injection volume: 10 μL. A calibration curve was created using several types of polymethyl methacrylate with known molecular weights (Polymer Laboratories, peak molecular weight (Mp) 1,560 to 19,500,000) as standard polymers, and Mw and Mn were determined.

[0160] <Measurement of Weight Average Molecular Weight (Mw) and Number Average Molecular Weight (Mn) of (Meth)acrylic Copolymer (A)> The weight average molecular weight (Mw) and number average molecular weight (Mn) of the macromonomer copolymer, which is the (meth)acrylic copolymer (A) obtained in the examples and comparative examples, were measured using gel permeation chromatography (GPC). 10 mg of the obtained copolymer was dissolved in 10 mL of tetrahydrofuran, and the solution was filtered through a 0.45 μm filter to prepare a sample for GPC measurement. For GPC measurement of the copolymer, a high-performance liquid chromatography measurement device (manufactured by Tosoh Corporation, model name: HLC-8320) was used, connected in series with a polymer measurement guard column (manufactured by Tosoh Corporation, product name: TSK-GEL SUPER HM-H) and one ultra-polymer measurement column (manufactured by Tosoh Corporation, product name: TSK-GEL GMH HR-H). A differential refractometer (RI) was used as the detector. Measurements were performed under the following conditions: separation column temperature: 40°C, mobile phase: tetrahydrofuran, mobile phase flow rate: 0.6 mL / min, and sample injection volume: 10 μL. Using several types of polymethyl methacrylate with known molecular weights (Polymer Laboratories, peak molecular weights (Mp) 1,560 to 19,500,000) as standard polymers, a calibration curve was created, and the weight-average molecular weight (Mw) and number-average molecular weight (Mn), which are relative molecular weights converted to polymethyl methacrylate, were determined.

[0161] <Measurement of weight average molecular weight (Mw) of (meth)acrylic polymer (B)> The weight average molecular weight (Mw) of the (meth)acrylic copolymer (B) in the particles of the present invention was measured using gel permeation chromatography (GPC). 10 mg of the obtained copolymer was dissolved in 10 mL of tetrahydrofuran, and the solution was filtered through a 0.45 μm filter to prepare a sample for GPC measurement. For GPC measurement of the copolymer, a high-performance liquid chromatography measuring device (manufactured by Tosoh Corporation, model name: HLC-8320) was used, connected in series with a polymer measurement guard column (manufactured by Tosoh Corporation, product name: TSK-GEL SUPER HM-H) and one ultra-polymer measurement column (manufactured by Tosoh Corporation, product name: TSK-GEL GMH HR-H). A differential refractometer (RI) was used as the detector. Measurements were performed under the following conditions: separation column temperature: 40°C, mobile phase: tetrahydrofuran, mobile phase flow rate: 0.6 mL / min, and sample injection volume: 10 μL. A calibration curve was created using several types of polymethyl methacrylate with known molecular weights (Polymer Laboratories, peak molecular weights (Mp) 1,560 to 19,500,000) as standard polymers, and the weight-average molecular weight (Mw), which is the relative molecular weight converted to polymethyl methacrylate, was determined.

[0162] <Measurement of particle MFR> The melt flow rate (unit: g / 10 min) of the particles obtained in the examples and comparative examples was measured using a melt indexer (manufactured by Techno Seven Co., Ltd., product name: L243) in accordance with JIS K7210 (Method A) at a temperature of 230°C and a load of 3.8 kg. The heating time for the particles was 5 minutes, and the time interval for cutting the molten particles was 5 to 120 seconds depending on the MFR value. The results are shown in Table 1.

[0163] <Measurement of particle size> The particle sizes of the particles obtained in the examples and comparative examples were measured using a HORIBA LA-960S laser diffraction / scattering particle size distribution analyzer. Particles were added to approximately 180 mL of ion-exchanged water (dispersion medium) so that the semiconductor laser transmittance was 90-80% and the LED transmittance was 90-70%, and flow cell measurements were performed. The volume-based median diameter was calculated using Mie scattering theory, which was used as the particle size. The results are shown in Table 1.

[0164] <Evaluation of particle powder flowability: Measurement of angle of repose> The angle of repose of the particles obtained in the examples and comparative examples was measured using an A, B, D powder property measuring instrument (Model A, B, D-72) manufactured by Tsutsui Scientific Instruments Co., Ltd. The powder was gently poured onto a disk to form a mound. The angle of the left base of the mound formed on the disk was measured. The above procedure was performed three times, and the average value was taken as the angle of repose. Two types of disks, one with a diameter of 60 mm and one with a diameter of 80 mm, were used, and the angle of repose was measured for each. Powders with an angle of repose of 40° or less were evaluated as having excellent powder fluidity. Powders with an angle of repose of more than 40° or where measurement was impossible because the angle of repose did not form a gentle peak and the angle of the base was unclear were evaluated as having insufficient powder fluidity. The measurement results of the angle of repose are shown in Table 1.

[0165] <Blocking resistance evaluation: Calculation of 60% crushing time> FIG. 1 shows the equipment used to prepare samples for evaluating blocking resistance. 20 g of the particles obtained in the examples and comparative examples were placed in a cylindrical case 2 having a bottom lid 1, and an upper lid 3 was placed on the particles. A 5 kg weight 5 was placed on top of the case 2 through a weight holder 4, and the load (pressure: 20 kPa / cm) of the weight 5 was applied to the particles. 2 ) and heated in a gear oven at 50°C for 6 hours to prepare a block-shaped sample. After sample preparation, the sample was cooled to room temperature and placed on a #12 mesh (1.4 mm opening) sieve using a Tsutsui Scientific Instruments Micro Electromagnetic Vibration Sieve (M-2 model) and shaken at the sieve's maximum vibration intensity. The time required for 60% of the block (12 g) to crumble was calculated as the 60% crushing time. A 60% crush time of 90 seconds or less was evaluated as having excellent blocking resistance, and a 60% crush time of more than 90 seconds was evaluated as having insufficient blocking resistance. The calculation results of the 60% crushing time are shown in Table 1.

[0166] <Moldability evaluation: MFR measurement> As an index of moldability of the molding materials obtained in the examples and comparative examples, the melt flow rate (unit: g / 10 min) was measured at a temperature of 230°C and a load of 3.8 kg using a melt indexer (manufactured by Techno Seven Co., Ltd., product name: L243) in accordance with JIS K7210 (Method A). The heating time of the molding material was 5 minutes, and the molding material cutting time interval was 5 to 120 seconds depending on the MFR value.

[0167] (raw materials) The abbreviations for the compounds used in the examples and comparative examples are as follows: MMA: Methyl methacrylate (Mitsubishi Chemical Corporation) MA: Methyl acrylate (Mitsubishi Chemical Corporation) BA: n-butyl acrylate (Mitsubishi Chemical Corporation) ST: Styrene (Fujifilm Wako Pure Chemical Industries, Ltd.) Dispersant (1): Dispersant prepared in Preparation Example 1 Chain transfer agent (1): The chain transfer catalyst prepared in Preparation Example 2 Polymerization initiator (1): 1,1,3,3-tetramethylbutylperoxy 2-ethylhexanoate (manufactured by NOF Corporation, trade name: Perocta O) Polymerization initiator (2): 2,2'-azobis(2-methylbutyronitrile) (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., trade name: V-59) ACRYPET (registered trademark) VH5: trade name, manufactured by Mitsubishi Chemical Corporation, a (meth)acrylic polymer containing 95% by mass or more of structural units derived from methyl methacrylate, a mass average molecular weight of 70,000, and MFR=5.5 g / 10 min (230° C., 37.3 N)

[0168] [Production Example 1: Synthesis of Dispersant (1)] A reactor equipped with a stirrer, a condenser, and a thermometer was charged with 61.6 parts of a 17% by mass aqueous solution of potassium hydroxide, 19.1 parts of MMA, and 19.3 parts of deionized water. The liquid in the reactor was then stirred at room temperature, and after confirming the exothermic peak, the mixture was stirred for 4 hours. After this, the reaction liquid in the reactor was cooled to room temperature to obtain an aqueous solution of potassium methacrylate.

[0169] Next, 900 parts of deionized water, 70 parts of a 42% by weight aqueous solution of sodium 2-sulfoethyl methacrylate (manufactured by Mitsubishi Chemical Corporation, trade name: Acryester SEM-Na), 16 parts of the above potassium methacrylate aqueous solution, and 7 parts of MMA were added to a polymerization apparatus equipped with a stirrer, condenser, and thermometer, and the mixture was stirred. While the atmosphere inside the polymerization apparatus was purged with nitrogen, the temperature inside the reaction apparatus was raised to 50°C. 0.053 parts of V-50 (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., trade name: 2,2'-azobis(2-methylpropionamidine) dihydrochloride) was added as a polymerization initiator to the polymerization apparatus, and the temperature inside the reaction apparatus was raised to 60°C. After adding the polymerization initiator, 1.4 parts of MMA was added in five increments (total amount of MMA: 7 parts) every 15 minutes. Thereafter, the liquid in the polymerization apparatus was kept at 60° C. for 6 hours while being stirred, and then cooled to room temperature to obtain a dispersant (1) in the form of a transparent aqueous solution with a solid content of 8% by mass.

[0170] [Production Example 2: Synthesis of Chain Transfer Agent (1)] In a synthesis apparatus equipped with a stirrer, 2.00 g (8.03 mmol) of cobalt (II) acetate tetrahydrate (Fujifilm Wako Pure Chemical Industries, Ltd., Wako Special Grade), 3.86 g (16.1 mmol) of diphenylglyoxime (Tokyo Chemical Industry Co., Ltd., EP Grade), and 100 mL of diethyl ether that had been deoxygenated in advance by nitrogen bubbling were placed under a nitrogen atmosphere, and the mixture was stirred at room temperature for 2 hours.

[0171] Next, 20 mL of boron trifluoride diethyl ether complex (manufactured by Tokyo Chemical Industry Co., Ltd., EP grade) was added, and the mixture was stirred for another 6 hours. The obtained mixture was filtered, and the solid was washed with diethyl ether and dried at 100 MPa or less at 20°C for 12 hours to obtain 5.02 g (7.93 mmol, yield 99% by mass) of chain transfer agent (1) as a brown solid.

[0172] [Production Example 3: Synthesis of Macromonomer (a1)] In a polymerization apparatus equipped with a stirrer, a condenser, and a thermometer, 145 parts of deionized water, 0.1 part of sodium sulfate (Na2SO4), and 0.26 parts by mass of dispersant (1) (solid content 8% by mass) produced in Production Example 1 were added and stirred to form a uniform aqueous solution. Next, 95 parts of MMA, 5.0 parts of MA, 0.0014 parts of chain transfer agent (1) produced in Production Example 2, and 0.25 parts of polymerization initiator (1) were added to form an aqueous dispersion.

[0173] The inside of the polymerization reactor was then thoroughly purged with nitrogen, and the aqueous dispersion was heated to 80°C and held there for 3 hours, then heated to 90°C and held there for 2 hours. The reaction solution was then cooled to 40°C to obtain an aqueous suspension of the macromonomer. This aqueous suspension was filtered through a filter cloth, and the filtrate was washed with deionized water and dried at 40°C for 16 hours to obtain macromonomer (a1) in the form of beads. The obtained macromonomer (a1) had a number average molecular weight (Mn) of 21,300 and a weight average molecular weight (Mw) of 39,100.

[0174] [Production Example 4: Synthesis of (meth)acrylic polymer (B)] A reaction vessel equipped with a stirrer, condenser, and thermometer was charged with a mixture of 280 parts deionized water, 1 part dipotassium alkenyl succinate, 0.12 parts potassium persulfate, 40 parts MMA, 2 parts BA, and 0.0057 parts n-octyl mercaptan. After purging the vessel with nitrogen, the reaction vessel was heated to 65°C with stirring and polymerized for 2 hours. A mixture of 44 parts MMA and 14 parts BA was then added to the reaction vessel over 1 hour. After the addition was completed, the mixture was stirred for 2 hours to complete the polymerization, yielding an emulsion of (meth)acrylic polymer (B). The resulting (meth)acrylic polymer (B) had a weight-average molecular weight (Mw) of 1,500,000 and a median diameter of 100 nm.

[0175] [Example 1] In a polymerization apparatus equipped with a stirrer, a condenser, and a thermometer, 75.0 parts of the macromonomer (a1) obtained in Production Example 3, 145 parts of deionized water, 0.1 parts of dispersant (1), and 0.5 parts of sodium sulfate were added and stirred to obtain an aqueous suspension. Next, the temperature inside the polymerization apparatus was raised to 70°C, and 20.8 parts of BA and 4.2 parts of ST were slowly added. The mixture was then stirred and maintained at 70°C for 1 hour to dissolve the macromonomer (a1) in the BA and ST, obtaining a dispersion. The polymerization apparatus was then cooled to 40°C, and 0.5 parts of polymerization initiator (2) was added and stirred for 30 minutes to dissolve the mixture. The atmosphere inside the polymerization apparatus was then thoroughly purged with nitrogen, and the aqueous dispersion was heated to 82°C and maintained for 4 hours, then heated to 90°C and maintained for 1 hour. Cooling to 40°C yielded a (meth)acrylic copolymer (A) in a syrup dispersion state. To the (meth)acrylic copolymer (A) in a syrup dispersion, 0.6 parts of magnesium sulfate and 4.5 parts of the (meth)acrylic copolymer (B) obtained in Production Example 4 were added and stirred, and the temperature inside the polymerization apparatus was raised to 85°C. The mixture was then maintained at 85°C for 10 minutes while stirring. After cooling to below 40°C, the mixture was filtered through a filter cloth and the filtrate was washed with deionized water. The filtrate was then dried at 40°C for 12 hours using a hot air circulation dryer to obtain particles (I-1) of the present invention, which are bead-shaped macromonomer copolymers containing (meth)acrylic copolymer (A) and (meth)acrylic copolymer (B). The melt flow rate measured for particles (I-1) was 31 g / 10 min. The particle diameter was 141 μm.

[0176] The (meth)acrylic copolymer (A) obtained in Example 1 had a number-average molecular weight (Mn) of 50,500 and a weight-average molecular weight (Mw) of 1,100,300. The angle of repose of the obtained particles (I-1) was 34° on a 60 mm diameter disk and 32° on an 80 mm diameter disk, indicating excellent powder fluidity. Furthermore, the 60% crushing time of the obtained particles (I-1) was 4 seconds, indicating excellent blocking resistance. The Tg of a homopolymer of styrene (St) is 100°C (POLYMER HANDBOOK FOURTH EDITION 2003), and the Tg of a homopolymer of n-butyl acrylate (BA) is -54°C (POLYMER HANDBOOK FOURTH EDITION 2003). The Tg of the (meth)acrylic polymer (A1) contained in the (meth)acrylic copolymer (A) was calculated using the Fox equation to be 110°C, and the Tg of the (meth)acrylic polymer (A2) was calculated using the Fox equation to be -37.5°C.

[0177] [Examples 2 and 3] Particles (I-2) and (I-3) of Examples 2 and 3 were obtained in the same manner as in Example 1, except that the amounts of macromonomer (a1) and monomer (a2) added were changed as shown in Table 1. The melt flow rate measured for particles (I-2) was 27 g / 10 min, and the particle diameter was 414 μm. The melt flow rate measured for particles (I-3) was 42 g / 10 min, and the particle diameter was 391 μm.

[0178] The (meth)acrylic copolymer (A) obtained in Example 2 had a number average molecular weight (Mn) of 61,500 and a weight average molecular weight (Mw) of 1,027,400. The angle of repose of the obtained particles (I-2) was 32° on a 60 mm diameter disk and 32° on an 80 mm diameter disk, indicating excellent powder flowability. Furthermore, the 60% crushing time of the obtained particles (I-2) was 2 seconds, indicating excellent blocking resistance.

[0179] The (meth)acrylic copolymer (A) obtained in Example 3 had a number average molecular weight (Mn) of 72,000 and a weight average molecular weight (Mw) of 1,113,500. The angle of repose of the obtained particles (I-3) was 34° on a 60 mm diameter disk and 35° on an 80 mm diameter disk, indicating excellent powder flowability. Furthermore, the 60% crushing time of the obtained particles (I-3) was 30 seconds, indicating excellent blocking resistance.

[0180] [Comparative Example 1] The (meth)acrylic copolymer (A) in the syrup dispersion state in Example 1 was filtered through a filter cloth, and the filtrate was washed with deionized water. The filtrate was then dried at 40°C for 12 hours using a hot air circulation dryer, yielding particles (I-4) consisting only of the (meth)acrylic copolymer (A), which is a bead-like macromonomer copolymer. The melt flow rate measured for particles (I-4) was 97g / 10min, and the particle diameter was 319µm.

[0181] The (meth)acrylic copolymer (A) obtained in Comparative Example 1 had a number average molecular weight (Mn) of 72,000 and a weight average molecular weight (Mw) of 1,113,500. The angle of repose of particles (I-4) on both 60 mm and 80 mm diameter disks was difficult to measure because it did not form a gentle hill, indicating insufficient powder flowability. Furthermore, the 60% crushing time of the obtained particles (I-4) was 1,200 seconds or more, resulting in insufficient blocking resistance.

[0182] [Table 1]

[0183] From Table 1, it can be seen that the particles of Examples 1 to 3, which correspond to the particles of the present invention, have excellent powder flowability and blocking resistance. In contrast to this, the particles of Comparative Example 1, which did not contain the (meth)acrylic polymer (B), were inferior in both powder flowability and blocking resistance.

[0184] [Example 4] A twin-screw extruder (product name: TEM-26SX) manufactured by Shibaura Machine was used to prepare pellet-shaped molding material as follows. 56 parts of the resulting particles (I-1) were melt-kneaded with 44 parts of VH5, a matrix resin made of PMMA, at a cylinder temperature of 200-230°C and a die temperature of 230°C to obtain a molding material in pellet form. The composition is shown in Table 2. The resulting pellets were dried and the melt flow rate was measured. The results are shown in Table 2.

[0185] [Examples 5 and 6] Pellet-shaped molding materials were prepared under the same conditions as in Example 4 using the particles (I-2) and (I-3) produced in Examples 2 and 3, respectively, except that the resin compositions were changed to those shown in Table 2, and the melt flow rates were measured in the same manner. The results are shown in Table 2.

[0186] Comparative Example 2 Using only VH5, a pellet-shaped molding material was prepared under the same conditions as in Example 4, and the melt flow rate was measured. The evaluation results are shown in Table 2.

[0187] [Table 2]

[0188] Comparing Examples 4 to 6 with Comparative Example 2, it is clear that the molding materials obtained in Examples 4 to 6 contain the particles of the present invention, and therefore have high melt flow rate values ​​and excellent moldability. [Explanation of symbols]

[0189] 1 Bottom lid 2 cases 3 Top lid 4 weight rack 5 weights< / z>

Claims

1. Particles containing a (meth)acrylic copolymer (A) and a (meth)acrylic polymer (B), the (meth)acrylic copolymer (A) is a block copolymer and / or a graft copolymer, the (meth)acrylic polymer (B) is a random copolymer and / or a homopolymer, The particles have a melt flow rate of 10 g / 10 min or more, measured in accordance with JIS K7210 (2014) at 230°C and 3.8 kg.

2. The particles according to claim 1, wherein the particle diameter is 30 μm or more and 600 μm or less.

3. The particles according to claim 1, wherein the content of the (meth)acrylic polymer (B) is 0.01 parts by mass or more and 20 parts by mass or less relative to 100 parts by mass of the (meth)acrylic copolymer (A).

4. The particle according to claim 1 , wherein the surface of the (meth)acrylic copolymer (A) is coated with the (meth)acrylic polymer (B).

5. the (meth)acrylic copolymer (A) contains a structural unit derived from a (meth)acrylic polymer (A1) and a structural unit derived from a (meth)acrylic polymer (A2), the (meth)acrylic polymer (A1) has a glass transition temperature of 50°C or higher, The particles according to claim 1, wherein the acrylic copolymer (A2) has a glass transition temperature of 0°C or lower.

6. The particles according to claim 1, wherein the (meth)acrylic polymer (B) has a glass transition temperature of 40°C or higher and lower than 80°C.

7. The particles according to claim 1, wherein the (meth)acrylic copolymer (A) has a weight average molecular weight of 50,000 or more and 2,500,000 or less.

8. The particles according to claim 1, wherein the (meth)acrylic polymer (B) has a weight average molecular weight of 50,000 or more and 5,000,000 or less.

9. The particle according to claim 1 , wherein the (meth)acrylic copolymer (A) comprises a graft copolymer.

10. The particle according to claim 5 , wherein the (meth)acrylic polymer (A1) contains a structural unit derived from a macromonomer (a1) represented by the following general formula (1): 【Chemical 1】 (In formula (1), R ０ ~R ｎ are each independently a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or a heterocyclic group. １ ~X ｎ are each independently a hydrogen atom or a methyl group. Z is a terminal group. n is a natural number from 1 to 10,000.

11. The particles according to claim 5 , wherein the (meth)acrylic polymer (A1) contains 50% by mass or more and 100% by mass or less of repeating units derived from methyl methacrylate.

12. The (meth)acrylic copolymer (A) is produced using a polymerizable composition (X) containing the macromonomer (a1) and the monomer (a2), The particles according to claim 10, wherein the monomer (a2) comprises at least one selected from the group consisting of methyl acrylate, 4-hydroxybutyl acrylate, 2-hydroxyethyl acrylate, ethyl acrylate, n-propyl acrylate, i-propyl acrylate, n-butyl acrylate, i-butyl acrylate, t-butyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, tridecyl acrylate, and i-stearyl acrylate.

13. A molding material comprising the particles according to any one of claims 1 to 12.

14. A molded article obtained by molding the molding material according to claim 13.

15. obtaining a suspension containing the (meth)acrylic copolymer (A) by suspension polymerization; a step of obtaining an emulsion containing the (meth)acrylic polymer (B) by emulsion polymerization; a step of mixing the suspension and the emulsion and heat-treating the mixture at a temperature equal to or higher than the glass transition temperature (Tg) of the (meth)acrylic copolymer (B); The method for producing particles according to any one of claims 1 to 12, comprising:

16. A method for producing a molded article, comprising molding a molding material produced by the method for producing particles according to claim 15.

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