JP2009249462A - Manufacturing method of polymer spherical particle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a powder having satisfactory melt fluidity, excellent powder fluidity and further having excellent safety, weatherability, flexibility, rubber elasticity, low temperature characteristics, adhesion properties to a polar resin, texture and appearance. <P>SOLUTION: A manufacturing method of a powder for a surface skin molding for automobile interior includes, in a method for obtaining polymer spherical particles by heating and stirring a water dispersion liquid including a dispersing element containing a thermoplastic elastomer composition, water and polyvinyl alcohol based dispersant to recover the solvent from the water dispersion liquid, a step (1) for forming a liquid droplet dispersion liquid of a polymer solution dissolved in a solvent in an aqueous solution including the water and the dispersant and casting the liquid droplet dispersion liquid into an evaporation reactor before the water dispersion liquid is stirred, a step (2) for obtaining the polymer spherical particles by casting steam into the liquid for heating to recover the solvent while stirring the water dispersion liquid of the liquid droplet of the polymer solution and a step (3) for separating the polymer spherical particles from the water dispersion liquid to obtain a polymer dried powder by aeration. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a powder for molding an automobile interior skin and a method for producing the same.

  Polymer powder particles are industrially used as a material for producing a molded body by mold molding or the like. In the mold molding, molding is performed by filling polymer powder particles in a desired molding mold and then melting and cooling the resin.

  In recent years, a molded body having a fine and complicated structure has been produced by such mold molding. In order to produce a molded body having such a fine structure, it is necessary to uniformly fill the mold with powder so that the powder material reaches every corner of the complex-shaped mold.

  As such a powder material, a vinyl chloride resin powder that is inexpensive, excellent in flexibility, and can be shaped into a complicated shape has been widely used (Patent Document 1). However, polyvinyl chloride resin generates harmful substances such as dioxins during incineration, and the plasticizers used there are suspected of acting as endocrine disrupting substances and carcinogenic substances. In terms of environmental pollution and safety, etc. There's a problem. There are also problems such as bleeding out and fogging derived from the plasticizer.

  Therefore, a thermoplastic elastomer sheet molding has been developed as an alternative to polyvinyl chloride resin powder. However, a sheet using a polyolefin-based elastomer or a styrene-based elastomer has a problem that the abrasion resistance, flexibility, and oil resistance are low (Patent Documents 2 to 6).

  In addition, the sheet using thermoplastic polyurethane has problems such as poor moldability and high cost (Patent Documents 7 and 8).

  In addition, the resin particles of the isobutylene block copolymer have a high resin adhesiveness and low hardness, so that a spherical powder with high powder flowability, uniform particle shape and small particle size is obtained. It was difficult to obtain, and most of the particles were non-spherical solid particles (Patent Document 9).

In recent years, as a material to solve such problems, powders composed of acrylic block copolymers with excellent safety, weather resistance, flexibility, rubber elasticity, low temperature characteristics, and adhesion to polar resins have been proposed. (Patent Document 10). However, the powder was finally obtained by physical pulverization at an extremely low temperature of −100 ° C., and it was only possible to obtain a powder having an irregular shape far from a spherical shape. For this reason, static electricity is likely to be generated between the powders, and further, due to the shape, the powders are difficult to flow. In addition, since particles that cannot pass through the sieve cannot be used, there is a disadvantage that the use efficiency of the raw material is lowered. Recently, a method of removing the solvent by steam stripping while stirring the solvent solution of the acrylic polymer in an aqueous dispersion system has been proposed. However, the particle size distribution obtained as a result of solvent evaporation is wide, the powder flowability is poor, and the yield in the target particle size range is poor. (Patent Document 11)
As described above, a high-quality molded article and skin preparation that is excellent in powder flowability and is safe and excellent in weather resistance, flexibility, rubber elasticity, low temperature characteristics, adhesion to polar resins, texture, appearance, etc. There has been a demand for a powder material capable of forming a coating film.
JP-A-5-279485 JP 49-53991 A JP 50-90693 A Japanese Patent Laid-Open No. 50-89494 JP-A-7-82433 Japanese Patent Laid-Open No. 10-30036 JP 2000-103957 A JP-A-7-133423 JP 2004-155880 A International Publication No. 2004/041886 Pamphlet JP 2006-225563 A

  In view of the current situation, the present application is a high-quality molding that is excellent in powder flowability and is safe and excellent in weather resistance, flexibility, rubber elasticity, low temperature characteristics, adhesion to polar resins, texture, appearance, and the like. An object of the present invention is to provide a skin molding powder for automobile interior which can form a body, a skin agent, a coating film and the like, and a method for producing the same.

  The present invention relates to a method for obtaining polymer spherical particles by collecting a polymer solution dissolved in a solvent, water and a water dispersion containing water and a dispersant while heating and recovering the solvent from the water dispersion. 1) a step of forming droplets of a polymer solution dissolved in a solvent in an aqueous solution containing water and a dispersant before stirring the aqueous dispersion and putting it into an evaporation reactor; and (2) a solution of the polymer solution. A step of recovering the solvent from the aqueous dispersion by heating with stirring the aqueous dispersion of droplets to obtain polymer spherical particles; and (3) from the aqueous dispersion containing the polymer spherical particles, The present invention relates to a method for producing a polymer spherical powder, comprising a step of separating particles.

  The present invention also provides an aqueous dispersion containing water and a dispersing agent and a polymer solution dissolved in a solvent, simultaneously introduced into a cleaved blade stationary mixer (static mixer), thereby allowing water droplets of the polymer solution to flow. Supplying and accumulating into a reactor for performing solvent evaporation while making a dispersion, and then collecting the solvent by adding steam while stirring to obtain an aqueous dispersion of polymer spherical particles The present invention relates to a method for producing a polymer spherical powder.

  Further, the present invention also provides a method in which a polymer solution dissolved in a solvent is ejected from a nozzle hole into an aqueous dispersion containing water and a dispersing agent to give regular vibration disturbance to the liquid, thereby dropping droplets into the aqueous dispersion. The above is characterized in that the polymer spherical particle aqueous dispersion is obtained by collecting a predetermined amount by supplying to a reactor for solvent evaporation while forming and then collecting the solvent by adding steam while stirring. The present invention relates to a method for producing a polymer spherical powder.

As the dispersant, methyl cellulose, polyvinyl alcohol, calcium phosphate, calcium carbonate or a nonionic surfactant is preferable. The glass transition temperature of the polymer is preferably 30 to 150 ° C. The polymer is preferably a thermoplastic resin, and the thermoplastic resin is preferably selected from a (meth) acrylic polymer, a (meth) acrylic copolymer, and an isobutylene polymer.
The polymer spherical powder of the present invention preferably has small pores having an inner diameter of 1 to 50% of the particle diameter on the particle surface. The polymer spherical powder of the present invention is preferably a powder for molding an automobile interior skin.

  In the method for producing a polymer spherical powder of the present invention, the dispersion (Y) is an inorganic particle (F1) 0 having a particle diameter of 0.1 to 30 μm with respect to 100 parts by weight of the thermoplastic elastomer composition (X). It is preferable to contain 5-10 weight part.

  In the polymer spherical powder of the present invention, 90% or more of the total number of powder particles has an aspect ratio of 1 to 2 expressed as a ratio of the minor axis to the major axis of the particles, and an average particle diameter of 150 μm or more. A powder obtained by adding 0 to 5 parts by weight of post-added particles (F2) to 100 parts by weight of a polymer spherical dry powder having a size of less than 300 μm is preferable.

  According to the production method of the present invention, powder having excellent powder fluidity, safety, and weather resistance, flexibility, rubber elasticity, low temperature characteristics, adhesion to polar resin, texture, appearance, etc. The material can be easily manufactured. Since powder is excellent in powder fluidity, it is suitable for powder slush molding. In addition, it is safe and excellent in weather resistance, flexibility, rubber elasticity, low temperature characteristics, adhesion to polar resins, texture, appearance and the like, and therefore can be suitably used for automobile interior skins.

  The present invention is described in detail below.

  The polymer spherical powder produced in the present invention preferably contains an acrylic block copolymer (A) and an acrylic polymer (B). Here, the acrylic block copolymer (A) is a methacrylic polymer block (a) having a glass transition temperature of 50 to 130 ° C., 15 to 50% by weight, acrylic acid-n-butyl, and ethyl acrylate. And 50 to 100% by weight of at least one monomer selected from the group consisting of 2-methoxyethyl acrylate and 50 to 0% by weight of different acrylates and / or vinyl monomers copolymerizable therewith The acrylic polymer block (b) having an acid anhydride group and / or a carboxyl group (b) is formed in an amount of 85 to 50% by weight, and the number average molecular weight measured by gel permeation chromatography is 30,000 to 200,000 acrylic block copolymer. The acrylic polymer (B) is an acrylic polymer having an average of 1.1 or more reactive functional groups (r) in one molecule.

<< Acrylic Block Copolymer (A) >>
The acrylic block copolymer (A) of the present invention may be a linear block copolymer, a branched (star) block copolymer, or a mixture thereof. The structure of such a block copolymer may be used depending on the required physical properties of the acrylic block copolymer (A). However, from the viewpoint of cost and ease of polymerization, the linear block copolymer is used. Polymers are preferred.

The linear block copolymer may have any structure. When the methacrylic polymer block (a) is expressed as a and the acrylic polymer block (b) is expressed as b in view of the physical properties of the linear block copolymer or the physical properties of the powder, (ab) _n At least one acrylic block selected from the group consisting of a type, b- (ab) _n- type and (ab) _n- a type (n is an integer of 1 or more, for example, an integer of 1 to 3) It preferably consists of a copolymer. Although not particularly limited, among these, from the viewpoint of ease of handling during processing and physical properties of the powder, ab type diblock copolymer, abb type triblock copolymer, or these Is preferred.

  As for the molecular weight of the acrylic block copolymer (A) used in the present invention, the number average molecular weight measured by gel permeation chromatography is 30,000 to 200,000. If the number average molecular weight is less than 30,000, sufficient mechanical properties as an elastomer may not be exhibited. Conversely, if the number average molecular weight is greater than 100,000, the processing characteristics may deteriorate. In the case of powder slush molding, it is necessary to flow even under non-pressurization. Therefore, if the molecular weight is large, the melt viscosity tends to increase and the moldability tends to deteriorate.

  In view of the above, the molecular weight of the preferred acrylic block copolymer (A) is preferably 35,000 to 150,000 in terms of number average molecular weight measured by gel permeation chromatography, more preferably 40,000 to 100,000.

  The ratio (Mw / Mn) of the weight average molecular weight (Mw) and the number average molecular weight (Mn) measured by gel permeation chromatography of the acrylic block copolymer (A) is not particularly limited, but is 1.8 or less. It is preferable that it is 1.5 or less. If Mw / Mn exceeds 1.8, the uniformity of the acrylic block copolymer may deteriorate.

  The molecular weight and molecular weight distribution of the acrylic block copolymer (A) are measured using, for example, a Waters GPC system (column: Shodex K-804 (polystyrene gel) manufactured by Showa Denko KK, mobile phase: chloroform). be able to. The number average molecular weight is a value expressed in terms of polystyrene.

  In the present invention, the methacrylic polymer block (a) and the acrylic polymer block (b) constituting the acrylic block copolymer (A) have a block (a) of 15 to 50% by weight, a block (b ) Is used at a composition ratio of 85 to 50% by weight. When the proportion of (a) is less than 15% by weight, the shape tends to be difficult to be retained during molding, and when the proportion of (b) is less than 50% by weight, the elasticity as an elastomer and the meltability during molding tend to decrease. is there. From the viewpoint of maintaining the shape during molding and the elasticity as an elastomer, the preferred range of the composition ratio is 20 to 45% by weight of (a), 80 to 55% by weight of (b), and more preferably (a ) Is 25 to 40% by weight, and (b) is 75 to 60% by weight.

<Methacrylic polymer block (a)>
The methacrylic polymer block (a) is a block formed by polymerizing a monomer having a methacrylic acid ester as a main component. Here, “having a methacrylic ester as a main component” means that the content of the methacrylic ester is the highest among all the monomer components constituting the methacrylic polymer block (a). In particular, the block (a) preferably comprises 50% by weight or more of methacrylic acid ester, and comprises 50 to 100% by weight of methacrylic acid ester and 0 to 50% by weight of other vinyl monomers copolymerizable therewith. Is more preferable. Moreover, you may contain the monomer which has a reactive functional group as a methacrylic ester and / or as another vinyl-type monomer. When the proportion of the methacrylic acid ester is less than 50% by weight, the weather resistance or the like that is characteristic of the methacrylic acid ester may be impaired.

  Examples of the methacrylic acid ester constituting the methacrylic polymer block (a) include, for example, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-pentyl methacrylate, methacrylic acid. Methacrylic acid aliphatic hydrocarbons such as n-hexyl acid, n-heptyl methacrylate, n-octyl methacrylate, 2-ethylhexyl methacrylate, nonyl methacrylate, decyl methacrylate, dodecyl methacrylate, stearyl methacrylate (for example, carbon number 1-18 alkyl) esters; methacrylic acid alicyclic hydrocarbon esters such as cyclohexyl methacrylate and isobornyl methacrylate; aralkyl methacrylates such as benzyl methacrylate; phenyl methacrylate, methacrylate Methacrylic acid aromatic hydrocarbon ester such as tolyl acid; ester of methacrylic acid such as 2-methoxyethyl methacrylate and 3-methoxybutyl methacrylate and functional group-containing alcohol having etheric oxygen; trifluoromethyl methacrylate, methacrylic acid Trifluoromethyl methyl acid, 2-trifluoromethyl ethyl methacrylate, 2-trifluoroethyl methacrylate, 2-perfluoroethyl ethyl methacrylate, 2-perfluoroethyl-2-perfluorobutyl ethyl methacrylate, methacrylic acid 2 -Perfluoroethyl, perfluoromethyl methacrylate, diperfluoromethyl methyl methacrylate, 2-perfluoromethyl 2-perfluoroethyl methyl methacrylate, 2-perfluorohexyl ethyl methacrylate, methacrylate Le acid 2 perfluorodecyl ethyl, and methacrylic acid fluorinated alkyl esters such as methacrylic acid 2-perfluoroalkyl-hexadecyl ethyl. These can be used alone or in combination of two or more thereof. Among these, methyl methacrylate is preferable in terms of processability, cost, and availability.

  Examples of vinyl monomers copolymerizable with the methacrylic acid ester constituting the methacrylic polymer block (a) include, for example, acrylic acid esters, aromatic alkenyl compounds, vinyl cyanide compounds, conjugated diene compounds, and halogen-containing compounds. Examples include unsaturated compounds, unsaturated carboxylic acid compounds, unsaturated dicarboxylic acid compounds, vinyl ester compounds, maleimide compounds, and the like.

  Examples of the acrylate ester include methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, isobutyl acrylate, n-pentyl acrylate, n-hexyl acrylate, n-heptyl acrylate, N-octyl acrylate, 2-ethylhexyl acrylate, nonyl acrylate, decyl acrylate, dodecyl acrylate, stearyl acrylate, and the like, acrylate aliphatic hydrocarbon (eg, alkyl having 1 to 18 carbon atoms) ester; cyclohexyl acrylate Acrylic alicyclic hydrocarbon esters such as isobornyl acrylate; aromatic acrylic hydrocarbon esters such as phenyl acrylate and toluyl acrylate; aralkyl acrylates such as benzyl acrylate; 2-methoxyethyl acrylate, acrylic Esters of acrylic acid such as 3-methoxybutyl and functional group-containing alcohols having etheric oxygen; trifluoromethyl methyl acrylate, 2-trifluoromethyl ethyl acrylate, 2-perfluoroethyl ethyl acrylate, acrylic acid 2 -Perfluoroethyl-2-perfluorobutylethyl, 2-perfluoroethyl acrylate, perfluoromethyl acrylate, diperfluoromethyl methyl acrylate, 2-perfluoromethyl-2-perfluoroethyl methyl acrylate, acrylic Examples thereof include fluorinated alkyl acrylates such as 2-perfluorohexylethyl acid, 2-perfluorodecylethyl acrylate, 2-perfluorohexadecylethyl acrylate, and the like.

  Examples of the aromatic alkenyl compound include styrene, α-methylstyrene, p-methylstyrene, p-methoxystyrene, and the like.

  Examples of the vinyl cyanide compound include acrylonitrile and methacrylonitrile.

  Examples of the conjugated diene compound include butadiene and isoprene.

  Examples of the halogen-containing unsaturated compound include vinyl chloride, vinylidene chloride, perfluoroethylene, perfluoropropylene, and vinylidene fluoride.

  Examples of the unsaturated carboxylic acid compound include methacrylic acid and acrylic acid.

Examples of the unsaturated dicarboxylic acid compound include maleic anhydride, maleic acid, monoalkyl esters and dialkyl esters of maleic acid, fumaric acid, monoalkyl esters and dialkyl esters of fumaric acid, and the like.
Examples of the vinyl ester compound include vinyl acetate, vinyl propionate, vinyl pivalate, vinyl benzoate, vinyl cinnamate, and the like.

  Examples of the maleimide compound include maleimide, methylmaleimide, ethylmaleimide, propylmaleimide, butylmaleimide, hexylmaleimide, octylmaleimide, dodecylmaleimide, stearylmaleimide, phenylmaleimide, cyclohexylmaleimide and the like.

  These can be used alone or in combination of two or more.

  These vinyl monomers are selected from the viewpoints of glass transition temperature required for the methacrylic polymer block (a), compatibility with the acrylic polymer block (b), and the like. These monomers may have a reactive functional group such as an acid anhydride group or a carboxyl group.

  The glass transition temperature of the methacrylic polymer block (a) is 50 to 130 ° C. When the glass transition temperature is lower than 50 ° C., the heat resistance of the automobile interior skin after molding is inferior, and there is a risk of deformation when the interior of the automobile becomes hot in summer or the like. Moreover, since it becomes difficult to melt | dissolve when it exceeds 130 degreeC, there exists a tendency for a moldability to deteriorate. Preferably it is 55-120 degreeC, More preferably, it is 60-110 degreeC, More preferably, it is 65-100 degreeC.

  The glass transition temperature (Tg) of the polymer (methacrylic polymer block (a) and acrylic polymer block (b) described later) is set according to the following Fox formula, and the weight of the monomer of each polymer portion This can be done by setting the ratio.

1 / Tg = (W ₁ / Tg ₁ ) + (W ₂ / Tg ₂ ) +... + (W _m / Tg _m ) W ₁ + W ₂ +... + W _m = 1
In the formula, Tg represents the glass transition temperature of the polymer portion, and Tg ₁ , Tg ₂ ,..., Tg _m represent the glass transition temperature of each polymerization monomer. W ₁ , W ₂ ,..., W _m represent the weight ratio of each polymerization monomer.

  The glass transition temperature of each polymerization monomer in the Fox formula may be, for example, a value described in Polymer Handbook Third Edition (Wiley-Interscience 1989).

  The glass transition temperature can be measured by DSC (differential scanning calorimetry) or tan δ peak of dynamic viscoelasticity, but the polarities of the methacrylic polymer block (a) and the acrylic polymer block (b). If they are too close, or if the number of monomer chains in the block is too small, the measured values may be misaligned with the calculation formula based on the Fox formula.

<Acrylic polymer block (b)>
The acrylic polymer block (b) is composed of 50 to 100% by weight of at least one monomer selected from the group consisting of acrylic acid-n-butyl, ethyl acrylate, and 2-methoxyethyl acrylate. It is formed from 50 to 0 weight of a different kind of polymerizable acrylic ester and / or vinyl monomer. Powder that is a characteristic when an acrylate ester is used when the ratio of at least one selected from the group consisting of n-butyl acrylate, ethyl acrylate, and 2-methoxyethyl acrylate is less than 50% by weight Physical properties, particularly flexibility and oil resistance, may be impaired.

  The above-mentioned acrylate-n-butyl, ethyl acrylate, and 2-methoxyethyl acrylate can be used alone or in combination of two or more thereof. Among these, acrylate-n-butyl is preferable from the viewpoint of rubber elasticity, low temperature characteristics, and cost balance. If oil resistance and mechanical properties are required, ethyl acrylate is preferred. Further, when it is necessary to impart low temperature characteristics and oil resistance and to improve the surface tackiness of the resin, 2-methoxyethyl acrylate is preferable. Further, when a balance between oil resistance and low temperature characteristics is required, a combination of ethyl acrylate, acrylic acid-n-butyl and acrylic acid-2-methoxyethyl is preferable.

  Although it does not specifically limit as a different acrylic ester and vinyl monomer which can be copolymerized with acrylic acid-n-butyl, ethyl acrylate, or 2-methoxyethyl acrylate, The above-mentioned acrylic ester (acrylic acid- n-butyl, ethyl acrylate or 2-methoxyethyl acrylate), methacrylic acid ester, aromatic alkenyl compound, vinyl cyanide compound, conjugated diene compound, halogen-containing unsaturated compound, unsaturated carboxylic acid compound, An unsaturated dicarboxylic acid compound, a vinyl ester compound, a maleimide compound and the like can be exemplified.

<Acid anhydride group and / or carboxyl group>
The acrylic polymer block (b) has an acid anhydride group and / or a carboxyl group. By introducing an acid anhydride group and / or a carboxyl group into the acrylic polymer block (b) as a crosslinking point, high rubber elasticity and compression set characteristics can be imparted to the automobile interior skin.

  When the number of acid anhydride groups and / or carboxyl groups is two or more, the mode in which the monomers are polymerized may be random copolymerization or block copolymerization. An example of the a-b-a type triblock copolymer is a- (b / z) -a type, (a / z)-(b / z)-(a / z) type, etc. It may be. Here, z represents a monomer or polymer block containing an acid anhydride group and / or a carboxyl group, and (b / z) represents an acid anhydride group and a polymer block (b). It represents that the monomer containing a carboxyl group is copolymerized.

  In the present invention, the acid anhydride group and the carboxyl group act as a reaction point or a crosslinking point for the acrylic block copolymer (A) to have a high molecular weight or to be crosslinked. Compared with other functional groups, the acid anhydride group and carboxyl group are easy to introduce into the acrylic block copolymer (A), and are preferable in terms of cost and reaction balance between low and high temperatures. It is a group.

  These acid anhydride groups and carboxyl groups are introduced into the acrylic polymer block (b) in a form protected with an appropriate protecting group, or a precursor of an acid anhydride group or carboxyl group, and thereafter It can also be converted into an acid anhydride group and / or a carboxyl group by a known chemical reaction.

  The content of acid anhydride group and carboxyl group is not particularly limited, and the cohesive strength, reactivity, structure and composition of acrylic block copolymer (A), acrylic block copolymer, and acid anhydride group and carboxyl group It can be appropriately set depending on the number of blocks constituting (A), the glass transition temperature, and the site and manner in which the acid anhydride group and carboxyl group are contained. When the content of acid anhydride groups and carboxyl groups is too small, the reaction between the acrylic block copolymer (A) and the acrylic polymer (B) is not sufficiently carried out, and the heat resistance due to the increase in the molecular weight and crosslinking. Since the improvement tends to be insufficient, it is preferable that an average of 1.0 acid anhydride group or carboxyl group per block is contained in the acrylic polymer block (b). It is more preferable that it is contained more than 1.5, and it is particularly preferable that 1.5 or more is contained.

  The acid anhydride group and / or carboxyl group may be contained only in the acrylic polymer block (b), or both of the methacrylic polymer block (a) and the acrylic polymer block (b). It may be contained in. Reaction point of acrylic block copolymer (A), block constituting acrylic block copolymer (A) (only acrylic polymer block (b), or methacrylic polymer block (a) and acrylic Depending on the purpose, such as the cohesive strength and glass transition temperature of the polymer block (b) and the required physical properties of the acrylic block copolymer (A), and / or carboxyl groups. It can be determined whether or not the group is also contained in the methacrylic polymer block (a). When it is necessary to improve the heat resistance and heat decomposability of the acrylic block copolymer (A), it is preferably introduced into the methacrylic polymer block (a).

It is preferable to introduce the acid anhydride group and / or carboxyl group in such a range that the flexibility, rubber elasticity, and low temperature characteristics of the acrylic block copolymer (A) are not deteriorated. When the cohesive force and glass transition temperature Tg _b of the acid anhydride group and / or the acrylic polymer block by the introduction of a carboxyl group (b) is increased, there is a tendency that flexibility, rubber elasticity, low temperature characteristics deteriorate. Specifically, the glass transition temperature Tg _b of the acrylic polymer block (b) after introducing the acid anhydride group and / or carboxyl group is preferably 25 ° C. or less, more preferably 0 ° C. Hereinafter, it is more preferably set to −20 ° C. or lower.

The Tg _b of the acrylic polymer block (b) can be set by setting the weight ratio of the monomers in each polymer portion according to the above Fox formula.

The relationship between the glass transition temperature of the methacrylic polymer block (a) and the acrylic polymer block (b) is that the glass transition temperature of the methacrylic polymer block (a) is Tg _a , and the acrylic polymer block (b) the glass transition temperature as Tg _b, it is preferable to satisfy the relation of the following equation.

Tg _a > Tg _b
When an acid anhydride group and / or a carboxyl group are also introduced into the methacrylic polymer block (a), it is preferably introduced within a range in which the moldability of the acrylic block copolymer (A) does not deteriorate. Although the case of performing the powder slush molding is required to flow in a non-pressure, the introduction of the acid anhydride group and / or carboxyl groups when the cohesive force and glass transition temperature Tg _a of the methacrylic polymer block (a) is increased The melt viscosity tends to increase and the moldability tends to deteriorate. Therefore, 130 ° C. Glass transition temperature Tg _a of Specifically, acid anhydride group and / or after the introduction of the carboxyl group methacrylic polymer block (a) or less, more preferably 110 ° C. or less, more preferably It introduce | transduces in the range which becomes 100 degrees C or less.

  Next, each of the acid anhydride group and the carboxyl group will be described.

<Acid anhydride group>
An acid anhydride group easily reacts with a hydroxyl group and an amino group. Further, when the composition contains a compound having an active proton, it easily reacts with an epoxy group.

  The acid anhydride group may be introduced into the main chain of the acrylic polymer block (b) or may be introduced into the side chain, but it may be introduced into the acrylic polymer block (b). In view of ease, it is preferably introduced into the main chain. The acid anhydride group is obtained by dehydration and condensation of two carboxyl groups. Specifically, the general formula (1):

(Wherein R ¹ is hydrogen or a methyl group, which may be the same or different from each other. N is an integer of 0 to 3, and m is an integer of 0 or 1). preferable.

  N in General formula (1) is an integer of 0-3, Preferably it is 0 or 1, More preferably, it is 1. When n is 4 or more, polymerization tends to be complicated, and cyclization of the acid anhydride group tends to be difficult.

  When the monomer having an acid anhydride group does not poison the catalyst under the polymerization conditions, the acid anhydride group is preferably introduced by direct polymerization. When the body deactivates the catalyst during polymerization, a method of introducing an acid anhydride group by functional group conversion is preferred. Although not particularly limited, it is preferable in terms of ease of introduction that it is introduced into the acrylic polymer block (b) in the form of a precursor of an acid anhydride group and then cyclized. :

(In the formula, R ² represents hydrogen or a methyl group. R ³ represents hydrogen, a methyl group, or a phenyl group, and at least two of the three R ³ groups in the formula consist of a methyl group and a phenyl group. And these may be the same or different from each other.) An acrylic block copolymer comprising at least one unit represented by the following formula: It is more preferable to introduce a desired acid anhydride group by cyclization.

  The introduction of the unit represented by the general formula (2) into the acrylic polymer block (b) is carried out by copolymerizing an acrylic ester or methacrylic ester monomer derived from the general formula (2). Can do. Examples of the monomer include t-butyl (meth) acrylate, isopropyl (meth) acrylate, α, α-dimethylbenzyl (meth) acrylate, α-methylbenzyl (meth) acrylate, and the like. It is not limited to these. Among these, (meth) acrylic acid-t-butyl is preferable from the viewpoints of availability, ease of polymerization, ease of acid anhydride group formation, and the like.

  The step of forming an acid anhydride group by cyclization from the precursor is preferably performed by heating an acrylic block copolymer having a precursor of an acid anhydride group at a high temperature, 180 to 300 ° C. It is preferable to carry out by heating. When the heating temperature is lower than 180 ° C., there is a tendency that the generation of acid anhydride groups tends to be insufficient. When the heating temperature is higher than 300 ° C., the acrylic block copolymer itself having a precursor of acid anhydride groups tends to decompose. is there.

<Carboxyl group>
Carboxyl groups easily react with epoxy groups and amino groups. The carboxyl group may be introduced into the main chain of the acrylic polymer block (b) or may be introduced into the side chain. The carboxyl group is preferably introduced into the main chain from the viewpoint of ease of introduction into the acrylic polymer block (b).

  Regarding the method for introducing a carboxyl group, when the monomer having a carboxyl group does not poison the catalyst under the polymerization conditions, it is preferably introduced by direct polymerization. When deactivating the catalyst, a method of introducing a carboxyl group by functional group conversion is preferred.

  In the method of introducing a carboxyl group by functional group conversion, it is introduced into the acrylic polymer block (b) in a form in which the carboxyl group is protected with an appropriate protective group, or in the form of a functional group that becomes a precursor of the carboxyl group, Thereafter, a carboxyl group can be generated by a known chemical reaction.

  Examples of the method for synthesizing the acrylic polymer block (b) having a carboxyl group include precursors of carboxyl groups such as tert-butyl methacrylate, tert-butyl acrylate, trimethylsilyl methacrylate, trimethylsilyl acrylate, and the like. A method of synthesizing an acrylic polymer block (b) containing a monomer having a functional group to form a carboxyl group and generating a carboxyl group by a known chemical reaction such as hydrolysis or acid decomposition (JP-A-10-298248, JP 2001-234146 A) and general formula (2):

(In the formula, R ² represents hydrogen or a methyl group. R ³ represents hydrogen, a methyl group, or a phenyl group, and at least two of the three R ³ groups in the formula consist of a methyl group and a phenyl group. And these may be the same or different from each other.) An acrylic block copolymer comprising at least one unit represented by the following formula: There is a way to introduce. The unit represented by the general formula (2) has a route through which an ester unit decomposes at a high temperature to generate a carboxyl group, followed by cyclization and an acid anhydride group. Utilizing this, the carboxyl group can be introduced by appropriately adjusting the heating temperature and time according to the type and content of the unit represented by the general formula (2). Moreover, a carboxyl group can also be introduce | transduced by hydrolyzing an acid anhydride group. The introduction of a carboxyl group by hydrolysis can be hydrolyzed by heating an acrylic block copolymer having a (carboxyl group) precursor in the presence of an acid catalyst. The reaction temperature at that time is preferably heated at 100 to 300 ° C. When the temperature is lower than 100 ° C., the carboxyl group tends to be insufficiently generated. When the temperature is higher than 300 ° C., the acrylic block copolymer itself having a carboxyl group precursor may be decomposed.

<< Production Method of Acrylic Block Copolymer (A) >>
The method for producing the acrylic block copolymer (A) is not particularly limited, but it is preferable to use controlled polymerization using a polymer initiator. Examples of controlled polymerization include living anion polymerization, radical polymerization using a chain transfer agent, and recently developed living radical polymerization. Of these, living radical polymerization is preferable from the viewpoint of controlling the molecular weight and structure of the acrylic block copolymer.

  Living radical polymerization is radical polymerization in which the activity at the polymerization terminal is maintained without loss. In the narrow sense, living polymerization refers to polymerization in which the terminal always has activity, but generally includes pseudo-living polymerization in which the terminal is inactivated and the terminal is in equilibrium. . The definition here is also the latter. Living radical polymerization has been actively researched by various groups in recent years.

  Examples thereof include those using a chain transfer agent such as polysulfide, cobalt porphyrin complex (J. Am. Chem. Soc., 1994, 116, 7943) and nitroxide. Compounds using radical scavengers such as compounds (Macromolecules, 1994, 27, 7228), atom transfer radical polymerization using organic halides as initiators and transition metal complexes as catalysts (Atom Transfer) And Radical Polymerization (ATRP). In the present invention, there is no particular restriction as to which of these methods is used, but atom transfer radical polymerization is preferable from the viewpoint of ease of control.

Atom transfer radical polymerization is polymerized using an organic halide or a sulfonyl halide compound as an initiator and a metal complex having a group 7 element, 8 group, 9 group, 10 group or 11 element as a central metal in the periodic table as a catalyst. (Eg, Matyjaszewski et al., J. Am. Chem. Soc., 1995, 117, 5614, Macromolecules. 1995, 28, 7901, Science, 1996, 272, 866, or Sawamoto et al., Macromolecules, 1995, 28, 1721). .
According to these methods, in general, polymerization proceeds in a living manner and the molecular weight distribution is narrow (Mw / M), although the polymerization rate is very high and radical reaction such as coupling between radicals is likely to occur. Mn = 1.1 to 1.5) polymer is obtained, and the molecular weight can be freely controlled by the charging ratio of the monomer and the initiator.

  In the atom transfer radical polymerization method, a monofunctional, difunctional, or polyfunctional compound can be used as the organic halide or sulfonyl halide compound used as an initiator. These may be properly used depending on the purpose. However, in the case of producing a diblock copolymer, a monofunctional compound is preferable from the viewpoint of easy availability of an initiator, and an aba triblock In the case of producing a copolymer and a b-a-b type triblock copolymer, it is preferable to use a bifunctional compound from the viewpoint of the number of reaction steps and shortening of the time. In the case of production, it is preferable to use a polyfunctional compound in terms of the number of reaction steps and time reduction.

  It is also possible to use a polymer initiator as the initiator. The polymer initiator is a compound composed of a polymer in which a halogen atom is bonded to the end of a molecular chain among organic halides or sulfonyl halide compounds. Since such a polymer initiator can be produced by a controlled polymerization method other than the living radical polymerization method, a block copolymer obtained by combining polymers obtained by different polymerization methods is obtained. .

Examples of monofunctional compounds include:
C ₆ H ₅ -CH ₂ X,
_{C 6 H 5 -C (H)} (X) -CH 3,
_{C 6 H 5 -C (X)} (CH 3) 2,
R ⁴ —C (H) (X) —COOR ⁵ ,
R ⁴ —C (CH ₃ ) (X) —COOR ⁵ ,
R ⁴ —C (H) (X) —CO—R ⁵ ,
R ⁴ —C (CH ₃ ) (X) —CO—R ⁵ ,
R ⁴ —C ₆ H ₄ —SO ₂ X
And the like.

In the formula, C ₆ H ₅ represents a phenyl group, and C ₆ H ₄ represents a phenylene group (which may be ortho-substituted, meta-substituted, or para-substituted). R ⁴ represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms. X represents chlorine, bromine or iodine. R ⁵ represents a monovalent organic group having 1 to 20 carbon atoms.

Specific examples of the alkyl group having 1 to 20 carbon atoms (including the alicyclic hydrocarbon group) as R ⁴ include, for example, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, Examples thereof include t-butyl group, n-pentyl group, n-hexyl group, cyclohexyl group, n-heptyl group, n-octyl group, 2-ethylhexyl group, nonyl group, decyl group, dodecyl group, isobornyl group and the like. Specific examples of the aryl group having 6 to 20 carbon atoms include a phenyl group, a tolyl group, a naphthyl group, and the like. Specific examples of the aralkyl group having 7 to 20 carbon atoms include benzyl group and phenethyl group.

Specific examples of the monovalent organic group having 1 to 20 carbon atoms which is R ⁵ include the same groups as R ⁴ .

  Specific examples of the monofunctional compound include, for example, tosyl bromide, methyl 2-bromide propionate, ethyl 2-bromide propionate, butyl 2-bromide propionate, methyl 2-isobutyrate bromide, 2- Examples thereof include ethyl bromide isobutyrate and 2-butyl isobutyrate bromide. Of these, ethyl 2-bromide propionate and butyl 2-bromide propionate are preferable because they are similar to the structure of the acrylate monomer and can easily control polymerization.

As a bifunctional compound, for example,
_{X-CH 2 -C 6 H 4} -CH 2 -X,
_{X-CH (CH 3) -C} 6 H 4 -CH (CH 3) -X,
_{X-C (CH 3) 2} -C 6 H 4 -C (CH 3) 2 -X,
^{_{X-CH (COOR 6) -}} (CH 2) n -CH (COOR 6) -X,
^{_{X-C (CH 3) (}} COOR 6) - (CH 2) n -C (CH 3) (COOR 6) -X,
^{_{X-CH (COR 6) -}} (CH 2) n -CH (COR 6) -X,
^{_{X-C (CH 3) (}} COR 6) - (CH 2) n -C (CH 3) (COR 6) -X,
_{X-CH 2 -CO-CH 2} -X, X-CH (CH 3) -CO-CH (CH 3) -X,
_{X-C (CH 3) 2} -CO-C (CH 3) 2 -X,
_{X-CH (C 6 H 5} ) -CO-CH (C 6 H 5) -X,
X—CH ₂ —COO— (CH ₂ ) _n —OCO—CH ₂ —X,
_{X-CH (CH 3) -COO-} (CH 2) n -OCO-CH (CH 3) -X,
_{X-C (CH 3) 2} -COO- (CH 2) n -OCO-C (CH 3) 2 -X,
_{X-CH 2 -CO-CO-} CH 2 -X,
_{X-CH (CH 3) -CO} -CO-CH (CH 3) -X,
_{X-C (CH 3) 2} -CO-CO-C (CH 3) 2 -X,
_{X-CH 2 -COO-C 6} H 4 -OCO-CH 2 -X,
_{X-CH (CH 3) -COO} -C 6 H 4 -OCO-CH (CH 3) -X,
_{X-C (CH 3) 2} -COO-C 6 H 4 -OCO-C (CH 3) 2 -X,
_{X-SO 2 -C 6 H 4} -SO 2 -X
And the like.

In the formula, R ⁶ represents an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms. n represents an integer of 0 to 20. C ₆ H ₅ , C ₆ H ₄ and X are the same as above.

Specific examples of the alkyl group having 1 to 20 carbon atoms, the aryl group having 6 to 20 carbon atoms, and the aralkyl group having 7 to 20 carbon atoms for R ⁶ include the alkyl group having 1 to 20 carbon atoms for R ⁴ , and 6 to 6 carbon atoms. Specific examples of 20 aryl groups and aralkyl groups having 7 to 20 carbon atoms are the same.

  Specific examples of the bifunctional compound include, for example, bis (bromomethyl) benzene, bis (1-bromoethyl) benzene, bis (1-bromoisopropyl) benzene, dimethyl 2,3-dibromosuccinate, and 2,3-dibromosuccinate. Diethyl acetate, dibutyl 2,3-dibromosuccinate, dimethyl 2,4-dibromoglutarate, diethyl 2,4-dibromoglutarate, dibutyl 2,4-dibromoglutarate, dimethyl 2,5-dibromoadipate, 2, Diethyl 5-dibromoadipate, Dibutyl 2,5-dibromoadipate, Dimethyl 2,6-dibromopimelate, Diethyl 2,6-dibromopimelate, Dibutyl 2,6-dibromopimelate, Dimethyl 2,7-dibromosuberate , 7-dibromosuberic acid diethyl, 2,7-dibromosuberine Dibutyl, and the like. Of these, bis (bromomethyl) benzene, diethyl 2,5-dibromoadipate, and diethyl 2,6-dibromopimelate are preferred from the viewpoint of availability of raw materials.

Examples of the polyfunctional compound include C ₆ H ₃ — (CH ₂ —X) ₃ , C ₆ H ₃ — (CH (CH ₃ ) —X) ₃ , C ₆ H ₃ — (C (CH ₃ ) _{2. -X) 3, C 6 H 3} - (OCO-CH 2 -X) 3, C 6 H 3 - (OCO-CH (CH 3) -X) 3, C 6 H 3 - (OCO-C (CH 3 ) ₂ -X) ₃ , C ₆ H _3- (SO ₂ -X) ₃ and the like.

In the formula, C ₆ H ₃ is a trisubstituted benzene ring (the position of the three bonds may be any combination in the 1st to 6th positions), and X is the same as above.

  Specific examples of the polyfunctional compound include tris (bromomethyl) benzene, tris (1-bromoethyl) benzene, tris (1-bromoisopropyl) benzene and the like. Of these, tris (bromomethyl) benzene is preferable from the viewpoint of availability of raw materials.

  In addition, when an organic halide or sulfonyl halide compound having a functional group is used in addition to the group for initiating polymerization, a polymer in which a functional group other than the group for initiating polymerization is easily introduced at the terminal or in the molecule is obtained. It is done. Examples of functional groups other than the group that initiates polymerization include alkenyl groups, hydroxyl groups, epoxy groups, amino groups, amide groups, silyl groups, and the like.

  In the organic halide or sulfonyl halide compound that can be used as an initiator, the carbon to which the halogen group (halogen atom) is bonded is bonded to the carbonyl group or the phenyl group, and the carbon-halogen bond is activated. Polymerization starts. The amount of the initiator to be used may be determined from the molar ratio with the monomer in accordance with the required molecular weight of the acrylic block copolymer. That is, the molecular weight of the acrylic block copolymer can be controlled by the number of monomers used per molecule of the initiator.

  The transition metal complex used as a catalyst for atom transfer radical polymerization is not particularly limited, but preferred are monovalent and zerovalent copper, divalent ruthenium, divalent iron, and divalent nickel. Complex.

  Among these, a copper complex is preferable from the viewpoint of cost and reaction control. Examples of the monovalent copper compound include cuprous chloride, cuprous bromide, cuprous iodide, cuprous cyanide, cuprous oxide, cuprous perchlorate, and the like. Of these, cuprous chloride and cuprous bromide are preferred from the viewpoint of polymerization control. When a monovalent copper compound is used, 2,2′-bipyridyl and its derivatives (for example, 4,4′-dinolyl-2,2′-bipyridyl, 4,4′-di (5- Noryl) -2,2′-bipyridyl and the like; 1,10-phenanthroline, derivatives thereof (for example, 4,7-dinolyl-1,10-phenanthroline, 5,6-dinolyl- 1,10-phenanthroline-based compounds such as 1,10-phenanthroline); polyamines such as tetramethylethylenediamine (TMEDA), pentamethyldiethylenetriamine, and hexamethyl (2-aminoethyl) amine may be added as a ligand. .

A tristriphenylphosphine complex of divalent ruthenium chloride (RuCl ₂ (PPh ₃ ) ₃ ) is also preferable as a catalyst. When a ruthenium compound is used as a catalyst, aluminum alkoxides may be added as an activator. Furthermore, a divalent iron bistriphenylphosphine complex (FeCl ₂ (PPh ₃ ) ₂ ), a divalent nickel bistriphenylphosphine complex (NiCl ₂ (PPh ₃ ) ₂ ), and a divalent nickel bistributylphosphine A complex (NiBr ₂ (PBu ₃ ) ₂ ) is also preferable as a catalyst.

  The kind of the catalyst, ligand and activator to be used is not particularly limited, and may be appropriately determined from the relationship between the initiator, monomer and solvent to be used and the required reaction rate. For example, in the polymerization of acrylic monomers such as acrylic acid esters, it is preferable from the viewpoint of polymerization control that the growth terminal of the polymer chain has a carbon-bromine bond, so that the initiator used is an organic bromide or It is a sulfonyl bromide compound, the solvent is preferably acetonitrile, copper bromide, preferably a metal complex catalyst centered on copper contained in cuprous bromide, and a ligand such as pentamethyldiethylenetriamine Is preferably used. For polymerization of methacrylic monomers such as methacrylic acid esters, it is preferable from the viewpoint of polymerization control that the growth terminal of the polymer chain has a carbon-chlorine bond. Or a sulfonyl chloride compound, the solvent is preferably a mixed solvent with acetonitrile and, if necessary, toluene, etc., using a metal complex catalyst having copper as the central metal, preferably copper contained in cuprous chloride It is preferable to use a ligand such as pentamethyldiethylenetriamine.

  The amount of catalyst and ligand to be used may be determined from the relationship between the amount of initiator, monomer and solvent to be used and the required reaction rate. For example, when trying to obtain a polymer with a high molecular weight, the initiator / monomer ratio must be smaller than when trying to obtain a polymer with a low molecular weight. Further, the reaction rate can be increased by increasing the number of catalysts and ligands. In addition, when a polymer having a glass transition point higher than room temperature is produced, the reaction rate tends to decrease when an appropriate organic solvent is added to lower the viscosity of the system and increase the stirring efficiency. In such a case, the reaction rate can be increased by increasing the number of catalysts and ligands.

  Atom transfer radical polymerization can be carried out in the absence of a solvent (bulk polymerization) or in various solvents. In addition, in bulk polymerization and polymerization performed in various solvents, the polymerization can be stopped midway.

  Examples of the solvent that can be used include hydrocarbon solvents, ether solvents, halogenated hydrocarbon solvents, ketone solvents, alcohol solvents, nitrile solvents, ester solvents, carbonate solvents, and the like.

  Examples of the hydrocarbon solvent include benzene and toluene. Examples of ether solvents include diethyl ether and tetrahydrofuran. Examples of the halogenated hydrocarbon solvent include methylene chloride and chloroform. Examples of the ketone solvent include acetone, methyl ethyl ketone, and methyl isobutyl ketone. Examples of the alcohol solvent include methanol, ethanol, propanol, isopropanol, n-butanol, t-butanol and the like. Examples of nitrile solvents include acetonitrile, propionitrile, benzonitrile and the like. Examples of ester solvents include ethyl acetate and butyl acetate. Examples of the carbonate solvent include ethylene carbonate and propylene carbonate.

  The solvent mentioned above can be used individually or in combination of 2 or more types.

  When a solvent is used, the amount used may be appropriately determined from the relationship between the viscosity of the entire system and the required stirring efficiency. In addition, even in the case of bulk polymerization and in the polymerization carried out in various solvents, the conversion rate of the monomer at the point of stopping the reaction is the relationship between the viscosity of the whole system and the required stirring efficiency. It may be determined as appropriate.

  Atom transfer radical polymerization can be performed in the range of 20 to 200 ° C, preferably in the range of 50 to 150 ° C.

  In order to produce an acrylic block copolymer by atom transfer radical polymerization, a method of sequentially adding monomers, a method of polymerizing the next block using a polymer synthesized in advance as a polymer initiator, and polymerizing separately Examples thereof include a method of bonding a polymer by reaction. Any of these methods may be used, and they may be properly used according to the purpose. From the viewpoint of simplicity of the production process, a method by sequential addition of monomers is preferred.

<< Acrylic polymer (B) >>
The acrylic polymer (B) is a polymer containing an average of 1.1 or more reactive functional groups (r) in one molecule. The acrylic polymer (B) having such a structure improves the molding fluidity as a plasticizer at the time of molding the powder, and at the same time, acid anhydride groups and carboxyls in the acrylic block copolymer (A) at the time of molding. The acrylic block copolymer (A) can be made to have a high molecular weight or be crosslinked by reacting with a reactive functional group (r). In addition, the number of reactive functional groups (r) here represents the average number of reactive functional groups (r) possessed per molecule of the acrylic polymer (B).

  The reactive functional group (r) in the acrylic polymer (B) is 1.1 or more, preferably 1.2 or more, more preferably 1.5 or more in the acrylic polymer (B). Particularly preferably, 2.0 or more are contained. The number is the reactivity of the reactive functional group (r), the site and mode of the reactive functional group (r), the acid anhydride group and / or the carboxyl group in the acrylic block copolymer (A). It is changed according to the number, part and style of the contained. When the functional group (r) content is less than 1.1, the effect of the block copolymer as a high molecular weight reaction agent or a crosslinking agent is reduced, and the heat resistance of the acrylic block copolymer (A) is improved. Tends to be insufficient.

  The acrylic polymer (B) is obtained by polymerizing one or more acrylic monomers, or one or two or more acrylic monomers and a monomer other than the acrylic monomer. It is preferable that it is obtained by polymerizing.

  Examples of the acrylic monomer include the acrylic acid esters described in the section of the methacrylic polymer block (a). Among these, it is preferable to use any one of acrylic acid-n-butyl, ethyl acrylate and acrylic acid-2-methoxyethyl, or a combination of two or more thereof.

  The monomer other than the acrylic monomer is not particularly limited as long as it is a monomer copolymerizable with the acrylic monomer. For example, the above-mentioned methacrylic acid ester, aromatic alkenyl compound, cyanide A vinyl compound, a conjugated diene compound, a halogen-containing unsaturated compound, an unsaturated carboxylic acid compound, an unsaturated dicarboxylic acid compound, a vinyl ester compound, a maleimide compound, or the like can be used.

  In addition, it is preferable that the ratio of the acrylic monomer component with respect to all the monomer components in an acrylic polymer (B) is 70 weight% or more. When the proportion is less than 70% by weight, the weather resistance is lowered and the compatibility with the acrylic block copolymer (A) tends to be lowered. Moreover, discoloration tends to occur in the molded product.

  The molecular weight of the acrylic polymer (B) is not particularly limited, but is preferably a low molecular weight having an average weight molecular weight of 30,000 or less, more preferably 500 to 30,000, and more preferably 500 to 10,000. Those are particularly preferred. If the weight average molecular weight is less than 500, the molded product tends to be sticky. On the other hand, if the weight average molecular weight exceeds 30,000, plasticization of the molded product tends to be insufficient.

  The molecular weight of the acrylic polymer (B) can be measured using, for example, a GPC system manufactured by Waters (column: Shodex K-804 (polystyrene gel) manufactured by Showa Denko KK, mobile phase: chloroform). The weight average molecular weight is a value expressed in terms of polystyrene.

  The viscosity of the acrylic polymer (B) is preferably 35,000 mPa · s or less when measured with a cone-plate type rotational viscometer (E-type viscometer) at 25 ° C., and 10,000 mPa · s. More preferably, it is 5,000 mPa · s or less. When the viscosity is higher than 35,000 mPa · s, the plasticizing effect of the powder tends to decrease. Although there is no particular lower limit of the preferred viscosity, the normal viscosity of the acrylic polymer is 10 mPa · s or more.

  The glass transition temperature Tg of the acrylic polymer (B) is preferably 100 ° C. or less, more preferably 25 ° C. or less, and more preferably 0 ° C. or less when measured by differential scanning calorimetry (DSC). More preferably, it is particularly preferably -30 ° C or lower. When glass transition temperature Tg exceeds 100 degreeC, there exists a tendency for the effect which improves a moldability as a plasticizer to become inadequate, and it exists in the tendency for the softness | flexibility of the molded object obtained to fall.

  The acrylic polymer (B) can be obtained by polymerizing by a known predetermined method. The polymerization method may be appropriately selected as necessary.For example, the polymerization may be performed by a method such as suspension polymerization, emulsion polymerization, bulk polymerization, living anion polymerization, polymerization using a chain transfer agent, and controlled polymerization such as living radical polymerization. However, controlled polymerization in which a polymer having good weather resistance and heat resistance and a relatively low molecular weight and a small molecular weight distribution can be obtained is preferable, and the method using high-temperature continuous polymerization described below is more preferable in terms of cost.

  The acrylic polymer (B) is preferably obtained by a polymerization reaction at a temperature of 180 to 350 ° C. At this polymerization temperature, an acrylic polymer having a relatively low molecular weight can be obtained without using a polymerization initiator or a chain transfer agent. For this reason, the acrylic polymer is an excellent plasticizer and has good weather resistance. Specifically, the method by high-temperature continuous polymerization described in JP-A-57-502171, JP-A-59-6207, JP-A-60-215007 and WO01 / 083619, An example is a method in which the monomer mixture is continuously supplied at a constant supply rate into a reactor set to a temperature and a pressure, and an amount of the reaction liquid corresponding to the supply amount is withdrawn.

<Reactive functional group (r)>
Examples of the reactive functional group (r) include an epoxy group, a hydroxyl group, an amino group, and a carboxyl group. Among these functional groups, from the reactivity with the acid anhydride group and carboxy group contained in the acrylic block copolymer (A) and the ease of introduction of the functional group into the acrylic polymer (B), Epoxy groups are preferred.

  Introduction of the reactive functional group (r) into the acrylic polymer (B) is, for example, a vinyl monomer having a reactive functional group (r) copolymerizable with a monomer constituting the acrylic polymer. It can be carried out by copolymerizing the body.

  Specific examples of the acrylic polymer (B) having a reactive functional group (r) include ARUFON (registered trademark) XG4000, ARUFON UG4000, ARUFON XG4010, ARUFON UG4010, ARUFON XD945, ARUFON XD950 from Toagosei Co., Ltd. ARUFON UG4030, ARUFON UG4070, etc. can be used suitably. These are all acrylic polymers such as acrylic and acrylate / styrene, and contain an average of 1.1 or more epoxy groups in one molecule.

<< Thermoplastic elastomer composition (X) >>
The thermoplastic elastomer composition (X) comprises an acrylic block copolymer (A) having an acid anhydride group and / or a carboxyl group, and an average of at least 1.1 reactive functional groups (r) per molecule. A thermoplastic elastomer composition comprising a compound (B) containing

  Although the ratio of the blend amount of the acrylic block copolymer (A) and the acrylic polymer (B) contained in the thermoplastic elastomer composition (X) is not particularly limited, the blend amount of the acrylic polymer (B) Is preferably 0.1 to 100 parts by weight, more preferably 1 to 50 parts by weight with respect to 100 parts by weight of the acrylic block copolymer (A). If the blending amount of the acrylic polymer (B) is less than 0.1 parts by weight, the crosslinking reaction with the acrylic block copolymer (A) does not proceed sufficiently, and the heat resistance of the molded product may be insufficient. If it is larger than 100 parts by weight, the crosslinking reaction proceeds excessively, and the elongation and flexibility of the molded product may be impaired.

  The thermoplastic elastomer composition (X) has a low melt viscosity at the time of molding and is excellent in moldability. On the other hand, an acid anhydride group and / or a carboxyl group and a reactive functional group (r) react with each other to form an acrylic block. It is preferable that the copolymer (A) has a high molecular weight or is crosslinked, and more preferably is crosslinked at the time of molding from the viewpoint of improving heat resistance.

  When crosslinking is required between the acrylic block copolymer (A) and the acrylic polymer (B), there is no particular limitation on the crosslinking method. For example, the acrylic block copolymer (A) and the acrylic polymer A crosslinked polymer can be obtained by using a kneader or the like that can melt-knead the composition containing (B) while heating.

  Various additives and catalysts may be added to the thermoplastic elastomer composition (X) as necessary in order to promote the reaction during molding. For example, when the reactive functional group (r) is an epoxy group, it is possible to use a curing agent generally used for epoxy resins such as acid anhydrides such as acid dianhydrides, amines, and imidazoles. When the functional functional group (r) is a hydroxyl group or a carboxyl group, a known esterification catalyst or transesterification catalyst such as divalent tin compounds and titanate esters can be used.

  In addition to the above acrylic block copolymer (A) and acrylic polymer (B), the thermoplastic elastomer composition (X) may contain stabilizers, lubricants, flame retardants, pigments, and fillers as necessary. An agent, a reinforcing agent, a tackifier, and a plasticizer can be appropriately blended. Specifically, stabilizers such as hindered phenol, hindered amine and dibutyltin maleate; lubricants such as polyethylene wax, polypropylene wax, montanic acid wax, and beef tallow extremely hardened oil; flame retardants such as decabromobiphenyl and decabromobiphenyl ether Fillers such as carbon black and activated carbon, reinforcing agents; coumarone / indene resin, phenol resin, terpene resin, high styrene resin, petroleum hydrocarbon (eg dicyclopentadiene resin, aliphatic cyclic hydrocarbon resin, unsaturated carbonization) Hydrogen resins, etc.), tackifiers such as polybutene and rosin derivatives, adipic acid derivatives, phthalic acid derivatives, glutaric acid derivatives, trimellitic acid derivatives, pyromellitic acid derivatives, polyester plasticizers, glycerin derivatives, epoxy derivatives polyester polymerization type Plasticity , Vinyl polymers obtained by polymerizing vinyl monomers such as polyether polymerization type plasticizers and acrylic plasticizers by various methods, hydroxybenzoic acid esters, N-alkylbenzenesulfonamides, N -Plasticizers such as polymer plasticizers such as alkyltoluenesulfonamides.

<< Dispersion (Y) >>
In the present invention, a polymer spherical powder is obtained from a dispersion (Y) containing a solvent (C), water (D) and a dispersant (E) in addition to the thermoplastic elastomer composition (X). A method of forming a dispersion is generally performed by physically stirring a mixture containing the above-described components. However, in order to obtain a desired droplet size in the droplet generation by stirring, a fine droplet is obtained. As a result, many yields are produced and the yield is poor. Accordingly, by introducing the polymer solvent solution and the aqueous dispersion containing the dispersant and the polymer solution dissolved in the solvent simultaneously into the stationary blade stationary type mixer (static mixer), the droplets of the polymer solution While making an aqueous dispersion, supply it to a reactor that performs solvent evaporation, accumulate a predetermined amount, and then evaporate and recover the solvent by evaporating and recovering the solvent by stirring slowly so as not to break the droplets. A method of obtaining an aqueous dispersion is preferred. More preferably, in an aqueous dispersion containing water and a dispersing agent, a regular vibration disturbance is given to the liquid in which the polymer solution dissolved in the solvent is ejected from the nozzle holes, so that droplets of uniform diameter are dispersed in the aqueous dispersion. After forming a certain amount and supplying it to a reactor that performs solvent evaporation and accumulating a predetermined amount, the temperature is raised while slowly stirring so as not to break the droplets, and the solvent is recovered to disperse the polymer spherical particles in water. A method of obtaining a liquid is more preferable.

<< Method for producing spherical powder >>
The spherical powder containing the thermoplastic elastomer composition (X) is obtained by heating a solution of the thermoplastic elastomer composition (X) dissolved in a solvent, an aqueous dispersion containing water and a dispersant while stirring. Can do.

  As a device used for stirring, a reactor having a jacket and a pitched paddle blade or other stirrer equipped with a stirring blade is used, but a large blade such as a Max blend blade is used for the purpose of preventing breakage of droplets. In general, it is preferable to stir from the stage of accumulating the droplet dispersion in order to avoid coalescence of droplets. .

  In the production of the spherical powder, the thermoplastic elastomer composition (X) solution, water and a dispersion (Y) containing an aqueous dispersion containing a dispersant are stirred, steam is blown, or jacket heating is performed. The temperature of the dispersion (Y) is increased until the temperature reaches a predetermined temperature of 90 ° C. or higher and lower than 110 ° C. When the temperature of the dispersion is low, the temperature rise due to steam blowing causes droplets to drop due to vibrational impact due to steam condensation. Since there is a risk of breaking, indirect heating using a jacket is preferable for raising the temperature at a low temperature stage. When the temperature of the dispersion is 90 ° C. or higher, the impact due to steam condensation becomes mild, and steam charging may be used.

  If the evaporating temperature to be raised is lower than 90 ° C., the amount of the residual solvent of the spherical particles is increased, and there is a possibility that the safety during drying, the solvent recovery rate, and the like are lowered. On the other hand, when the temperature is 110 ° C. or higher, the spherical particles of the polymer are softened, so that aggregation or the like may occur and the particles may not be dispersed in a single spherical shape.

  The solvent that dissolves the thermoplastic elastomer composition (X) is not particularly limited, and a solvent that dissolves the thermoplastic elastomer composition (X) is appropriately selected. The boiling point of the solvent is preferably 25 ° C. or higher, more preferably 30 ° C. or higher at normal pressure (1 atm) in consideration of handling at room temperature. In addition, since the solvent is finally evaporated, the boiling point of the solvent is preferably 130 ° C. or less at normal pressure (1 atm), more preferably 120 ° C. or less, and particularly preferably 100 ° C. or less. .

  Specific examples of the solvent include aliphatic hydrocarbons such as pentane, hexane, heptane, cyclohexane and cyclopentane, aromatic hydrocarbons such as benzene, toluene, ethylbenzene and xylene, methyl ethyl ether, diethyl ether and Examples thereof include ethers such as tetrahydrofuran, esters such as ethyl acetate, and halogenated hydrocarbons such as dichloromethane and chloroform.

  The amount of the solvent used is appropriately selected in consideration of the concentration and viscosity of the thermoplastic elastomer composition (X) solution, but the solid content concentration of the thermoplastic elastomer composition (X) solution is 5 to 70% by weight. It is preferable to use a solvent. If the solid content concentration of the thermoplastic elastomer composition (X) solution is less than 5% by weight, the yield is low and not efficient, whereas if it exceeds 70% by weight, the viscosity of the whole solution becomes too high, and the thermoplasticity by stirring. There is a possibility that the elastomer composition (X) is not sufficiently dispersed. More preferably, the solvent is used so that the solid content concentration of the thermoplastic elastomer composition (X) solution is 20 to 50% by weight, and more preferably 10 to 30% by weight.

<Water (D)>
In the production of the spherical powder, water (D) 2 to 5 times the weight of the thermoplastic elastomer composition (X) is used. The amount of water to be used can be appropriately determined in consideration of the desired polymer particle size and the like.

  The amount of water is preferably 3 to 4 times the weight of the thermoplastic elastomer composition (X). If it is less than 2 times the weight, the particles may aggregate and the particle size may become too large. If it is more than 5 times the weight, the yield per reactor will be reduced, and a large amount of dispersing agent will be required. It may not be preferable.

  The water to be used is not particularly limited, and any type of water such as soft water, hard water, tap water, ion exchange water, pure water, and distilled water may be used. Ion exchange water, pure water and distilled water are preferred from the viewpoint of preventing impurities from being mixed.

<Dispersant (E)>
Although it does not specifically limit about the dispersing agent used in order to manufacture the spherical powder of this invention, Cellulose resins, such as methylcellulose, hydroxyethylcellulose, hydroxypropylmethylcellulose, carboxymethylcellulose, polyvinyl alcohol, polyethyleneglycol, polyvinylpyrrolidone polyacrylamide , Organic materials such as polystyrene sulfonate, inorganic solids such as calcium phosphate and calcium carbonate, glycerin fatty acid ester, sorbitan ester, propylene glycol fatty acid ester, sucrose fatty acid ester, citric acid mono (di or tri) stearate ester, pentaerythritol fatty acid ester , Trimethylolpropane fatty acid ester, polyglycerin fatty acid ester, polyoxyethylene glycerin fatty acid ester , Polyester, polyoxyethylene sorbitan fatty acid ester, polyethylene glycol fatty acid ester, polypropylene glycol fatty acid ester, polyoxyethylene glycol fatty alcohol ether, polyoxyethylene alkylphenyl ether, N, N-bis (2-hydroxyethylene) fatty amine, ethylene Examples thereof include bis-stearic acid amide, condensation products of fatty acids and diethanol, block polymers of polyoxyethylene and polyoxypropylene, and nonionic surfactants such as polyethylene glycol and polypropylene glycol. These are appropriately selected according to the polymer to be used, and among them, one kind selected from the group consisting of methyl cellulose, polyvinyl alcohol, calcium phosphate, calcium carbonate and a nonionic surfactant because of good dispersibility. It is preferable to use the above. Only one dispersant can be used, or two or more dispersants can be used in combination. When two or more types are used in combination, the combination is not particularly limited, but it is preferable to use a mixture of two or more types selected from methyl cellulose, polyvinyl alcohol, calcium phosphate, calcium carbonate, and a nonionic surfactant. When two or more types of mixtures are used, the temperature is initially increased after a predetermined temperature using one type of dispersant for the purpose of protecting droplets at low temperatures and protecting droplets at high temperatures. It is also possible to add a dispersant. For example, it is generally considered that a dispersant with a small molecular weight has a higher adsorption rate on the surface of the droplet, and a protective force with a higher molecular weight is higher, so select multiple dispersants from this perspective. Can do. Further, the dispersant for forming the droplets and the dispersant for evaporating the solvent may be separate.

  When polyvinyl alcohol or methylcellulose is used as a dispersant, it is preferable to use each of them alone because it is easier to obtain a desired spherical powder, but calcium carbonate can also be used in combination. When a nonionic surfactant is used, it can be used alone, but it is preferable to use calcium carbonate in combination because particle formation becomes easy. In this case, the weight ratio of nonionic surfactant / calcium carbonate is preferably 50 or less, more preferably 3 to 30, and particularly preferably 5 to 20.

  About the usage-amount of a dispersing agent, the dispersion | distribution performance with respect to a polymer and the property of a solvent are considered suitably. For example, the dispersant is preferably added in an amount of 0.3 to 1 part by weight, more preferably 0.4 to 0.9 part by weight, more preferably 0.5 to 100 parts by weight based on 100 parts by weight of the thermoplastic elastomer composition (X). It is particularly preferable to add 0.8 part by weight. If the amount is less than 0.3 parts by weight, the polymer may not be sufficiently dispersed and particles may be difficult to form, and even if added more than 1 part by weight, the dispersion characteristics are not particularly changed, which is economically undesirable. Moreover, it may adversely affect physical properties such as transparency and moldability of the polymer.

  The order of adding the dispersant is not particularly limited, and the dispersant may be added to water before the addition of the thermoplastic elastomer composition (X) solution, and the thermoplastic elastomer composition (X) may be added before the addition of water. A dispersant in solution may be added.

<Inorganic particles (F1)>
If necessary, the dispersion (Y) may contain inorganic particles (F1) having a particle size of 0.1 to 30 μm.

  Such inorganic particles (F1) are not particularly limited, but include asbestos, glass fiber, mica, graphite, diatomaceous earth, white clay, silica (fumed silica, precipitated silica, crystalline silica, fused silica, dolomite, anhydrous Reinforcing fillers such as silicic acid, hydrous silicic acid, etc .; magnesium carbonate, diatomaceous earth, calcined clay, clay, talc, titanium oxide, bentonite, ferric oxide, red pepper, aluminum fine powder, flint powder, zinc oxide, Examples thereof include fillers such as activated zinc white, zinc dust, zinc carbonate and shirasu balloon; glass fibers and glass filaments. These can be used alone or in combination of two or more.

  Among these inorganic particles, titanium oxide, silica, and talc are preferable from the viewpoint of improving mechanical properties, reinforcing effect, cost, and the like.

  In the case of silica, silica whose surface is previously hydrophobically treated with an organosilicon compound such as organosilane, organosilazane, or diorganopolysiloxane may be used.

  The content of the inorganic particles (F1) is preferably 0.5 to 20 parts by weight with respect to 100 parts by weight of the thermoplastic elastomer composition (X). When the addition amount is small, the reinforcing effect of the obtained molded product may not be sufficient, and when the addition amount is too large, the moldability of the resulting powder tends to be lowered. The addition amount is more preferably 1 to 15 parts by weight, particularly preferably 3 to 12 parts by weight, based on 100 parts by weight of the thermoplastic elastomer composition (X).

The inorganic particles (F1) have a particle size of 0.1 to 30 μm. If the particles are smaller than 0.1 μm, the resulting molded article may not have sufficient reinforcing effect. If larger than 30 μm, the spherical particles may not be obtained as a result of the inorganic particles protruding from the powder surface. . Preferably it is 0.5-25 micrometers, Most preferably, it is 1-20 micrometers.
<Steam stripping process>
The spherical powder can be obtained by heating the aqueous dispersion to remove most of the solvent and then removing the solvent from the aqueous dispersion by steam stripping.

  Steam stripping is performed for 5 minutes or more and less than 2 hours. The required time is selected from 5 minutes to less than 2 hours so that the solvent is almost completely distilled off according to the composition of the thermoplastic elastomer composition (X). Further, in the steam stripping step, the solvent is removed to form polymer particles, so that the solution is sufficiently stirred.

  The vessel used for steam stripping only needs to be connected so that the pipe for introducing the steam is inserted into the liquid phase, and the method of introducing the steam into the stirring vessel is preferably used as in the suspension and solvent removal operations. Is done. In addition, the steam stripping operation can be carried out by venting steam in the same tank as the heating performed when stirring the aqueous dispersion of the polymer solution, or can be continued by providing a separate stripping tank. You can also. In addition, as a continuous method, when one or more aeration stirring tanks are connected to the heating / stirring tank of the dispersion (Y), stripping can also be performed by contacting the steam and the resin slurry by a shelf system. . Since the removal efficiency of the solvent is high, it is preferable to perform steam stripping in the same tank together with the heating performed when stirring the aqueous dispersion of the polymer solution.

  The temperature of the aqueous dispersion during steam stripping is a predetermined temperature of 90 ° C. or higher and lower than 110 ° C. The temperature is preferably changed depending on the solvent used, and is preferably equal to or higher than the azeotropic temperature of the solvent and water. When performing steam stripping at 100 ° C. or higher, it can be carried out by narrowing the evaporation outlet line and pressurizing the inside of the tank.

  The solvent evaporated by heating and / or steam stripping can then be cooled through a cooling tower or the like and recovered. If necessary, it can be reused in the polymerization step by purification after separation from the aqueous phase.

<Drying process>
The spherical powder can be separated by filtering and centrifuging the aqueous dispersion subjected to the above treatment. The separated polymer powder can be made into a spherical powder by drying by aeration using a hot air heat receiving dryer such as a fluid dryer.

<< About spherical powder >>
In the present invention, the spherical powder refers to a powder recognized by those skilled in the art as spherical. In the spherical powder of the present invention, 90% or more of the total number of powder particles has an aspect ratio of 1 to 2 expressed as a ratio of a minor axis to a major axis of the particles, and an average particle diameter of 150 μm to 300 μm. Those less than are preferred. Note that the closer the aspect ratio of the spherical powder is to 1, the closer it is to a true sphere and the higher the fluidity of the particles. The particles that can be obtained in the present invention preferably have an aspect ratio of 90% or more of the total number of powder particles of 1-2, more preferably 1-1. Is particularly preferred.

  In the present invention, the aspect ratio of the particles is orthogonal to the line connecting the longest diameter and the longest diameter of the particles by taking a photograph with a magnification of 100 to 200 times using a magnifying glass (a KEYENCE microscope). The longest part is measured as the minor axis. The major axis / minor axis is evaluated as the aspect ratio. Each aspect ratio is evaluated for about 300 particles. The ratio of particles having an aspect ratio of 1 to 2 to the total number of powder particles is calculated as [(number of particles having an aspect ratio of 1 to 2) / (total number of evaluated particles)] × 100 (%). Can do.

  The average particle size of the spherical powder of the present invention is preferably 150 μm or more and less than 300 μm. When the particle diameter is larger than 300 μm, molding using a mold having a fine structure is not preferable because molding abnormalities are likely to occur. On the other hand, when the thickness is smaller than 150 μm, static electricity or the like is likely to occur, and the fluidity may deteriorate. Moreover, the said particle diameter can be adjusted by adjusting the quantity of a dispersing agent, the ratio of a polymer solution and water, etc. according to the intended use. In the present invention, particles having a smaller particle diameter can be obtained as the amount of the dispersant is increased and as the ratio of polymer solution / water (v / v) is decreased. For example, when a spherical powder is used for mold molding such as powder slush molding, it is preferably 170 μm or more and less than 280 μm in consideration of powder fluidity and moldability, and 190 μm or more and less than 260 μm. It is more preferable that

  In the present application, the average particle diameter of the spherical powder is a value obtained by sieving the dry spherical powder with a standard sieve and individually weighing the fractions belonging to each particle size range to obtain an average value based on the weight standard. It is. The average particle diameter can be determined using, for example, an electromagnetic sieve shaker (manufactured by Lecce, AS200BASIC (60 Hz)).

  The obtained spherical powder preferably has small pores having an inner diameter of 1 to 50% of the particle diameter on the particle surface. More preferably, the inner diameter is 3 to 40% of the particle diameter, and particularly preferably 5 to 25%. In the present invention, the ratio between the particle diameter and the inner diameter can be determined by observing with a microscope.

<< Post-added particles (F2) >>
The powder for molding an automobile interior skin of the present invention may be the polymer powder itself obtained as described above, or may contain post-added particles (F2) to prevent the powder from agglomerating. Also good.

  Although it does not specifically limit as post-addition particle | grains (F2), In addition to what was illustrated as an example of inorganic particle | grains (F1), calcium carbonates, such as light calcium carbonate, heavy calcium carbonate, and colloidal calcium carbonate, etc. can be used. . In addition, fine particles made of an organic resin other than inorganic particles can be used.

  As the fine particles made of organic resin, formaldehyde-based condensate, polymethyl methacrylate-based resin, methacrylic compound, styrene-based resin fine particles, and the like can be used. Of these, titanium oxide, calcium carbonate, silica, talc, and polymethyl methacrylate resin are preferable from the viewpoint of improving mechanical properties, reinforcing effect, cost, and the like.

  In the present invention, the post-added particles (F2) are added in an amount of 0 to 100 parts by weight of the polymer spherical powder obtained by removing the solvent (C) and water (D) from the dispersion (Y). 5 parts by weight can be added. In addition, when there is little addition amount, the reinforcement effect of the molded object obtained may not be enough. On the other hand, if the addition amount is too large, the moldability of the obtained powder tends to be lowered. Therefore, it is preferable to add 1-4 parts by weight, and it is more preferable to add 2-3 parts by weight.

  Furthermore, carbon black, activated carbon, etc. can also be mix | blended as needed.

<< About car interior skins >>
The above-mentioned automotive interior skin molding powder can be powder slush molded to produce an automotive interior skin. Although the method of powder slush molding is not particularly limited, an example of the procedure is as follows.

  A mold release agent (silicone mold release agent or the like) is applied to the mold at a temperature of 60 ° C. or less by spraying or brushing, and the mold is heated by hot sand heating, oil heating or the like. Next, the powder for molding the skin for automobile interior is introduced into the mold and held for 10 to 45 seconds to weld the powder, then the excess unwelded powder is removed, and further 60 to 300 seconds, preferably After completing the welding of the material by holding for 70 to 120 seconds, the molded body (usually 0.2 to 2 mm thick sheet) is obtained by cooling and demolding the mold by water cooling or the like.

  EXAMPLES Next, although this invention is demonstrated further in detail based on an Example, this invention is not limited only to these Examples.

In the examples, the following abbreviations were used.
BA: n-butyl acrylate MEA: 2-methoxyethyl acrylate MMA: methyl methacrylate TBA: t-butyl acrylate EA: ethyl acrylate The molecular weight and molecular weight distribution of the polymers shown in the examples are manufactured by Waters. Measurement was performed using a GPC system (column: Shodex K-804 (polystyrene gel) manufactured by Showa Denko KK, mobile phase: chloroform). The number average molecular weight is expressed in terms of polystyrene.

  Each particle diameter and average particle diameter of the polymer spherical powder were measured by using an electromagnetic sieve shaker (manufactured by Lecce Co., Ltd., AS200BASIC (60 Hz)). Among these, the average particle diameter was specifically measured as follows.

First, using standard sieves having openings of 4000 μm, 2000 μm, 1000 μm, 710 μm, 500 μm, 300 μm, 212 μm, 100 μm, and 53 μm, respectively, and using an electromagnetic sieve shaker (manufactured by Lecce, AS200BASIC (60 Hz)) for 10 minutes Vibrating sieving was performed, and the particles remaining on each sieve were collected and weighed. At this time, particles of 4000 μm or more were excluded. The particle weight on a sieve with an opening of 2000 μm was converted as W3000, average particle diameter (4000 + 2000) / 2 = 3000 μm, and similarly the weight on a 1000 μm sieve was W1500, the particle diameter was 1500 μm, the weight on the 710 μm sieve was W855, and the particle diameter was 855 μm. The weight on the 500 μm sieve is W605 and the particle diameter is 605 μm. The weight on the 300 μm sieve is W400 and the particle diameter is 400 μm. A particle weight of 76.5 μm at W76.5 and a particle weight of 53 μm or less was handled as an average particle size of 26.5 μm at W26.5. The total weight of each was taken as WT, and the weight average diameter Dave (μm) was calculated by the following equation.
Dave = (3000 × W3000 + 1500 × W1500 + 855 × W855 + 605 × W605 + 400 × W400 + 256 × W256 + 156 × W156 + 76.5 × W76.5 + 26.5 × W26.5) / WT
The aspect ratio of the powder particles was determined as follows.

  Take a photograph at a magnification of 100 to 200 times using a magnifying glass (Keyence microscope), the longest part of the particle is the major axis, the longest part is perpendicular to the line connecting the major axis and the longest part is the minor axis The major axis / minor axis was measured as an aspect ratio. Each aspect ratio was evaluated for about 300 particles. The ratio of particles having an aspect ratio of 1 to 2 to the total number of powder particles was calculated as [(number of particles having an aspect ratio of 1 to 2) / (total number of evaluated particles)] × 100 (%).

  The micrograph of the powder for molding automobile interior skin was observed and photographed using an S-800 microscope manufactured by Hitachi.

<Method for measuring conversion rate of polymerization reaction>
The conversion rate of the polymerization reaction shown in this example was measured using the following analyzer and conditions.
Equipment used: Gas chromatography GC-14B manufactured by Shimadzu Corporation
Separation column: J & W SCIENTIFIC INC,
Capillary column Supercoux-10, 0.35mmφ × 30m
Separation conditions: Initial temperature 60 ° C, hold for 3.5 minutes
Temperature increase rate 40 ° C / min
Final temperature 140 ° C, hold for 1.5 minutes
Injection temperature 250 ° C
Detector temperature 250 ° C
Sample preparation: The sample was diluted about 10 times with ethyl acetate, and butyl acetate or acetonitrile was used as an internal standard substance.

<Glass transition temperature>
The glass transition temperature of the methacrylic polymer block (a) constituting the acrylic block copolymer (A) is a ratio of loss elastic modulus / storage elastic modulus at 50 ° C. to 130 ° C. (tan δ) in dynamic viscoelasticity measurement. Was measured as the temperature showing the maximum value of.

  The measurement is based on JIS K-6394 (Testing method for dynamic properties of vulcanized rubber and thermoplastic rubber). A test piece having a length of 6 mm, a width of 5 mm, and a thickness of 2 mm is cut out and a dynamic viscoelasticity measuring apparatus DVA-200 ( Using IT Measurement Control Co., Ltd.), the measurement frequency was 0.5 Hz.

<Abrasion resistance evaluation test>
Samples having a width of 3 cm and a length of 10 cm were cut out from the sheets obtained by powder slush molding in Examples and Comparative Examples, and subjected to an abrasion test using an abrasion tester.
Equipment used: Haydon type abrasion tester 14DR (manufactured by Shinto Kagaku Co., Ltd.) Movement speed: 6000 mm / min Movement length: 5 cm Number of movements: 5 Reciprocating load weight: 1 kg Wear jig: ASTM sample jig, jig sample It was fixed to the shaft so that it was always parallel to the axis. A semi-cylinder obtained by cutting a cylinder made of aluminum and having a diameter of 2.5 cm and a length of 1 cm in half was bonded to the lower side of the ASTM jig. On top of that, a cloth with a gold width of 3 was attached in a quadruple roll and fixed with an ASTM jig stopper.

After the test, the wear resistance was evaluated by visual observation. The evaluation criteria are as follows.
Things that do not clearly show scratches from the front; ○
Slightly scratched when seen from the front;
Those with obvious scratches such as whitening and erosion; ×
<Scratch resistance>
A sample having a width of 10 cm and a length of 10 cm was cut out from a sheet obtained by powder slush molding in Examples and Comparative Examples, and attached to a mount to obtain a measurement sample. A scratch test was conducted under the following conditions.
Equipment used: Tabers clutch tester (manufactured by Toyo Seiki Co., Ltd.) Rotation speed: 0.5 rpm Cutter: Tungsten carbide, 4.8 mm square x 19 mm length, cutting edge radius 12.7 mm Direction of cutter: Cutter blade side down The cutter was attached so that the long side of the cutter was on top.

After the test was performed with a load of 1 N, the scratch resistance was evaluated by visual observation. The evaluation criteria are as follows.
Things that do not clearly show scratches from the front; ○
Slightly scratched when seen from the front;
Those with obvious scratches such as whitening and erosion; ×
<Ethanol resistance test>
The ethanol resistance shown in the examples and comparative examples was measured under the following conditions.

The textured sheet produced in the examples and comparative examples was placed on a flat surface, and one drop of a solution obtained by diluting ethanol (manufactured by Wako Pure Chemical Industries, Ltd.) with pure water to 50% by weight with a pipette, Left at room temperature for 24 hours. Thereafter, the surface was visually observed and evaluated according to the following criteria.
No trace; ○
Traces are visible but not whitened;
What can be bleached; ×
<Oil resistance test>
The oil resistance shown in the examples and comparative examples was measured under the following conditions.

The textured sheet produced in the examples and comparative examples was placed on a flat surface, and one drop of liquid paraffin (manufactured by Nacalai Tesque) was dropped on the pipette and left at 100 ° C. for 24 hours. Thereafter, liquid paraffin was wiped off with Kimwipe (registered trademark) (manufactured by Crecia Co., Ltd.), and the surface was visually observed and evaluated according to the following criteria.
No trace; ○
Traces are visible but not whitened;
What can be bleached; ×
<Heat resistance test>
The heat resistance shown in the examples and comparative examples was measured under the following conditions.
The embossed sheet produced in Examples and Comparative Examples was left at 120 ° C. for 24 hours. Thereafter, the surface was visually observed and evaluated according to the following criteria.
No change in wrinkle pattern; ○
Although the change of the wrinkle pattern is not clear, the surface gloss increased compared to the initial stage;
Changes in wrinkle pattern observed; ×
<Urethane adhesion test>
A urethane foam mold (140 mm long × 200 mm wide × 10 mm high with a lid, SUS304) was obtained by preliminarily setting the skin material obtained by slush molding according to the embodiment using the powder for car interior skin molding. Made of the skin material face down. Urethane on which a skin material was set by stirring 17 g of polyisocyanate (CEI-264 manufactured by Nippon Polyurethane Industry Co., Ltd.) and 34 g of polyol (manufactured by Sanyo Chemical Industries, Ltd., HC-150) at room temperature for 10 seconds with a hand mixer. After pouring into the foaming mold, it was capped and allowed to foam for 2.5 minutes. After completion of foaming, a sample was taken out from the foaming mold, and after curing at room temperature for 24 hours, the skin material was peeled off from the foamed urethane by hand to observe the state of destruction, and evaluated according to the following criteria.
Urethane material that has been destroyed; ○
Some breakage occurs at the interface between the skin material and urethane;
Breaking at the interface between the skin material and urethane; ×
<Melability>
The resulting molded sheet was observed on the textured surface and the molded back surface and evaluated according to the following criteria.
Good wrinkle transfer and no pinholes / bubbles: ○
Good texture transfer, no pinholes / bubbles, but some found around the mold: △
Wrinkle transfer is not good, or pinhole / bubbles are recognized even at the center of the mold: ×
<Powder flowability>
The back side of the obtained molded sheet was observed and evaluated according to the following criteria.
Good powder filling at the corners of the mold and the back of the ribs; ○
Insufficient powder filling at part of mold corner and rib back;
Insufficient powder filling at most corners of mold corners and ribs; x
<Repose angle>
The angle of repose is determined by using a powder tester made by Hosokawa Micron and slowly dropping the particles from a height of 11 cm above the disk floated from the desk by the method shown in FIG. ) Was evaluated. Note that the angle of repose is an index that indicates the ease of collapse of powder particles and the ease of flow of powder particles in a static state. The smaller the angle of repose, the better the powder flowability of the particles. , Particles are easy to reach every corner of the mold.

<Apparent specific gravity>
The apparent specific gravity was measured using a Hosokawa Micron powder tester by the method shown in FIG. The particles were calculated by filling a container of known volume and dividing the weight of the particle by the volume of the container. The apparent specific gravity is an index indicating the magnitude of the filling rate of the resin. When a resin powder having a small apparent specific gravity is used, a molded body having many voids is easily formed during molding.

<ICI flow time>
In the ICI flow, a funnel-shaped metallic container shown in FIG. 2 is filled with a certain weight of resin powder, and the time from when the bottom lid is opened until the powder is completely discharged is measured. The ICI flow is an index indicating the ease of flow of the powder particles in the dynamic state of the powder particles, and a small ICI flow time indicates that the powder flowability of the particles is good. , The particles tend to spread quickly to every corner of the mold.

<Moldability>
The moldability was comprehensively judged by performing powder slush molding using a box-shaped embossed die, and determining how the embossed pattern was formed, whether there were pinholes on the bottom and boundary surfaces, and irregularities on the molding back surface. Specifically, as described in Example 1, using a container with a lid as shown in FIG. 3, the container is heated to 260 ° C., inverted to be filled with resin powder, and inverted to be a textured surface. The resin was dropped to form a sheet. The moldability criteria are as follows: The texture pattern of the mold is clearly transferred, there are no pinholes on the bottom surface or boundary surface, and there is no unevenness on the back surface of the molding: Smooth
There is a problem with any of the embossed pattern, pinhole, or unevenness on the back of the molding: ×
(Production Example 1)
Synthesis of acrylic block copolymer After replacing 2m3 pressure-resistant reactor with nitrogen, 688 g (4.80 mol) of copper bromide, 78400 g (612 mol) of BA and 2870 g (22.4 mol) of TBA were charged and stirring was started. did. Thereafter, a solution prepared by dissolving 1320 g (3.69 mol) of diethyl 2,5-dibromoadipate as an initiator in 7140 g of acetonitrile (nitrogen bubbling) was charged and stirred for 30 minutes while raising the solution temperature to 75 ° C. . When the solution temperature reached 75 ° C., 83.2 g (0.48 mol) of the ligand pentamethyldiethylenetriamine was added to initiate polymerization of the acrylic polymer block.

  At regular intervals from the start of polymerization, about 100 mL of the polymerization solution was sampled from the polymerization solution for sampling, and the conversion rates of BA and TBA were determined by gas chromatography analysis of the sampling solution. During polymerization, the polymerization rate was controlled by adding pentamethyldiethylenetriamine as needed. Pentamethyldiethylenetriamine was added twice in total (166 g in total) during the acrylic polymer block polymerization.

  When the conversion rate of BA was 99.1% and the conversion rate of TBA was 99.3%, MMA 48300 g (482 mol), EA 7840 g (78.3 mol), copper chloride 475 g (4.8 mol), pentamethyldiethylenetriamine 83.2 g (0.48 mol) and 104000 g of toluene (nitrogen bubbled) were added to initiate polymerization of the methacrylic polymer block.

  Sampling was performed when MMA and EA were added, and conversion rates of MMA and EA were determined based on this. After adding MMA and EA, the internal temperature was set to 85 ° C. During polymerization, the polymerization rate was controlled by adding pentamethyldiethylenetriamine as needed. Pentamethyldiethylenetriamine was added a total of 6 times (total 499 g) during methacrylic polymer block polymerization. When the conversion rate of MMA was 95.9%, 250,000 g of toluene was added, and the reactor was cooled to complete the reaction. When the GPC analysis of the obtained (meth) acrylic block copolymer was conducted, the number average molecular weight Mn was 53100, and molecular weight distribution Mw / Mn was 1.46.

  Toluene was added to the resulting reaction solution to make the polymer concentration 25% by weight. To this solution, 2190 g of p-toluenesulfonic acid was added, the inside of the reactor was purged with nitrogen, and the mixture was stirred at 30 ° C. for 3 hours.

  The reaction solution was sampled to confirm that the solution was colorless and transparent, and 6570 g of Radiolite # 3000 manufactured by Showa Chemical Industry was added.

Thereafter, the reactor was pressurized to 0.1 to 0.4 MPaG with nitrogen, and the solid content was separated using a pressure filter (filter area 0.45 m ² ) equipped with polyester felt as a filter medium. It was 101 degreeC when the glass transition temperature of the methacrylic polymer block (a) obtained by this manufacture example 1 was computed according to the said Fox formula.

(Production Example 2)
11.25 g of Irganox 1010 (manufactured by Ciba Specialty Chemicals) was added to and dissolved in about 45.0 kg of the filtered block copolymer solution obtained in Production Example 1. The reactor was purged with nitrogen, stirred at an internal temperature of 150 ° C. for 2 hours, and then cooled to 60 ° C. Kyoward 500SH (131.0 g) was added, the inside of the reactor was purged with nitrogen, and the mixture was stirred at 30 ° C. for 2 hours. The reaction solution was sampled, it was confirmed that the solution was neutral, and 225 g of Radiolite # 3000 manufactured by Showa Chemical Industry was added. Thereafter, the reactor was pressurized to 0.1 to 0.2 MPaG with nitrogen, and a filter press type pressure filter equipped with a filter paper (NA-100) manufactured by ADVANTEC as a filter medium (filtering area using one chamber) The solid content was separated using 200 cm ² , 120S-SL manufactured by CMT Co. LTD., To obtain a polymer solution. Subsequently, ARUFON XG4010 (manufactured by Toagosei Co., Ltd.) as an acrylic polymer (B) with respect to 100 parts by weight of the acrylic block copolymer (A) in 12 kg of the polymer solution (solid concentration 25%) 10 parts by weight of epoxy resin containing 1.1 or more epoxy groups per molecule (approximate value 4 (from catalog)), carbon black (Asahi Carbon Co., Ltd., Asahi # 15) 1.4 weight Part, lubricant (Nippon Yushi Co., Ltd., beef tallow extremely hardened oil) at a ratio of 1.0 part by weight, and stirred and mixed to obtain a polymer solution.
(Production Example 3) Before carrying out the static mixer solvent evaporation, a production example of an aqueous dispersion of polymer solution droplets is shown. As a matrix of the aqueous dispersion, 30 kg of 0.1% aqueous solution of polyvinyl alcohol (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name Gohsenol KH-17) was prepared as a dispersant. Using a static mixer (3 / 8-N30-232-F) manufactured by Noritake Company Limited as a cleaved blade stationary mixer, the polyvinyl alcohol aqueous solution and the polymer solution obtained in Production Example 2 were used. An aqueous dispersion of droplets of the polymer solution is prepared by supplying a flow ratio of 1: 2. (Polyvinyl aqueous solution flow rate 20 kg / h) The polymer solution and polyvinyl alcohol aqueous solution were continuously supplied to the static mixer for 1 hr, and a solvent evaporation reactor having a Max blend blade was placed at the outlet of the static mixer. While stirring the blend blade at 10 rpm, a droplet of aqueous dispersion of 30 kg polymer solution was collected in a 100 L solvent evaporation reactor. As a result, 30 kg of a droplet aqueous dispersion of a polymer solution having a droplet diameter of about 500 μm was collected in an evaporation reactor although there were few fine droplets.
(Production Example 4) A production example of an aqueous dispersion of droplets of a polymer solution will be described before carrying out evaporation of the droplet-generating solvent. As a matrix of the aqueous dispersion, 30 kg of 0.1% aqueous solution of polyvinyl alcohol (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name Gohsenol KH-17) was prepared as a dispersant. The following apparatus is used as the droplet generator. (FIG. 4) That is, in a droplet manufacturing apparatus including a liquid introduction port (6) and a plate (1) having a hole for ejecting a droplet target liquid, a hole for ejecting the droplet target liquid is provided in the nozzle. A vibration partition wall (3) for applying vibration to the droplet target liquid and a droplet manufacturing apparatus (FIG. 4) provided with a vibrator are used. In addition, a solvent evaporation reactor is disposed above the droplet production apparatus. In the droplet manufacturing apparatus, the nozzle is arranged at the center of a plate having a diameter of 16 cm, and the nozzle has 45 holes having a diameter of 0.17 mm, with the distance between adjacent holes being 4 mm. The solvent evaporation reactor equipped with a slurry chamber (15, capacity 10 L) with an inner diameter of 16 cm and a height of 50 cm and a Max blend blade was filled with 20 kg of the above aqueous solution of polyvinyl alcohol, and the evaporator was stirred slowly at 10 rpm. While stirring, the polymer solution, which is the liquid to be dropped, is further supplied from the liquid inlet (6) at 10 kg / h, and at the same time, the polyvinyl alcohol aqueous solution is supplied from the liquid inlet (12) to the droplet chamber at 20 kg / h. A droplet of an O / W type polymer solution is created by applying a vibration of 800 Hz with a shaker, and an aqueous dispersion of a slurry of the polymer solution that floats due to the difference in specific gravity and overflows from the droplet chamber The liquid was introduced into a 1 hr evaporation reactor. As a result, 30 kg of an aqueous dispersion of substantially homogeneous polymer solution droplets having a droplet diameter of 450 μm and few microdroplets was collected in an evaporation reactor.
(Manufacturing Example 5) Droplet generation (Lincal reception)
Before carrying out the solvent evaporation, an example of the preparation of an aqueous dispersion of polymer solution droplets is given. As the base of the aqueous dispersion, 30 kg of 0.05% aqueous solution of polyvinyl alcohol (trade name Gohsenol KH-17, manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) and 10 kg of 0.75% aqueous lincal dispersion are prepared as a dispersant. did. The lincol dispersion was charged into an evaporation reactor, droplets were generated by the same apparatus and operation as in Production Example 4, and a droplet slurry aqueous dispersion of the polymer solution was introduced into the 1 hr evaporation reactor. As a result, 30 kg of an aqueous dispersion of substantially homogeneous polymer solution droplets having a droplet diameter of 450 μm was collected in an evaporation reactor.
(Production Example 6) 200 parts of synthetic water of emulsion polymerization latex, 0.28 part of sodium dioctylsulfosuccinate, 0.0015 part of ferrous sulfate (FeSO ₄ .7H ₂ O), 0.006 part of ethylenediaminetetraacetic acid and SFS0. 5 parts was charged into a reactor equipped with a stirrer, and after nitrogen substitution, the temperature was raised to 60 ° C. To this, a mixture of 90 parts of methyl methacrylate, 10 parts of butyl acrylate, 0.8 part of tertiary dodecyl mercaptan and 1 part of cumene hydroperoxide (purity 82%) was added over 6 hours, and 2 hours after the start of addition. 0.33 parts of sodium dioctyl sulfosuccinate was added after 4 hours and 0.39 parts. After completion of addition, 0.05 part of formaldehyde sulfoxylate formed on the substrate is added and polymerization is performed for 1 hour, and an acrylic ester latex having a polymerization conversion rate of 99%, a glass transition degree of 92 ° C., and a solid content concentration of 33% is obtained. Obtained.

Example 1
The droplet dispersion of the polymer solution prepared using the static mixer in Production Example 3 was heated to 90 ° C. by indirect heating through steam to the jacket while stirring at 200 rpm using a Max Blend blade as the stirring blade. When the temperature reached 90 ° C., steam was blown from the bottom of the stirring tank to raise the temperature to 100 ° C. The solvent gas evaporated by the temperature rise was introduced into the condenser, and the solvent was sequentially recovered. Even after reaching 100 ° C., steam was continuously supplied, and after 1 hour, the introduction of steam was stopped, the water was cooled by passing water through the jacket, and the internal temperature was lowered to 60 ° C. Next, 263 g (4.2 parts based on the solid content) of the polymer latex produced by emulsion polymerization prepared in Production Example 6 was added, and 771 g of a 15% sodium sulfate aqueous solution (5.6 parts as the solid content) was added for 5 minutes. Over time. After 5 minutes from the end of the addition, the polymer particles are heated to 90 ° C., kept at the temperature for 5 minutes, and then passed through the jacket to cool the internal temperature to 40 ° C., and the latex particles adhere to the polymer spherical particle surface. A slurry was obtained. The average particle diameter of the obtained spherical particles was 210 μm, and the fine particles of 100 microns or less were 3%. The resin slurry was dehydrated by treatment at 3000 rpm using a basket type centrifugal dehydrator (Sanyo Riken Kikai Seisakusho, SYK-5000-15A) equipped with a polyester filter cloth, and the resin powder was recovered. The dehydrated resin was fluidized and dried with hot air at 70 ° C. to dry the moisture content to 0.5% to obtain dry spherical polymer particles, which were used as a powder for molding automobile interior skins.

Using the obtained powder for car interior skin molding, slush molding was performed as follows. The powder for molding the car interior skin was put into a 500 g powder box, and the flat plate with grain heated to 260 ° C. was set in the box containing the powder for car interior skin molding, and then cooled to 250 ° C. When the embossed flat plate reached 250 ° C., it was inverted and allowed to stand for 6 seconds, and then inverted again. Thereafter, excess unwelded powder was shaken off, and when 60 seconds had passed, the mold was cooled with cooling water for 40 seconds. Thereafter, the sheet was peeled off from the mold to obtain a molded sheet. Table 1 shows a list of the average particle diameter of the spherical powder for molding obtained by drying, the content of fine particles of 100 μm or less, the powder characteristics, and the evaluation results of the molded body sheet.
(Example 2)
Latex treatment was performed by performing solvent evaporation in the same manner as in Example 1 except that the droplet dispersion liquid produced using the vibration type droplet production apparatus in Production Example 4 was used. The obtained spherical particles had an average particle size of 220 μm and fine particles of 100 microns or less were 2%. The obtained spherical particle slurry was dehydrated or dried in the same manner as in Example 1 to obtain dry spherical polymer particles, and slush molding was performed. Table 1 shows the results of the powder characteristics and moldability of the dry powder.
(Example 3)
A 3.0% aqueous solution of polyvinyl alcohol (manufactured by Kuraray, trade name Poval 235) is used at 85 ° C. during the temperature increase of the solvent evaporation, using the droplet dispersion liquid manufactured using the vibration type droplet generator in Production Example 5. Except for adding 250 g, solvent evaporation was performed in the same manner as in Example 1 to perform latex treatment. The average particle diameter of the obtained spherical particles was 225 μm, and the fine particles of 100 microns or less were 1%. The obtained spherical particle slurry was dehydrated or dried in the same manner as in Example 1 to obtain dry spherical polymer particles, and slush molding was performed. Table 1 shows the results of the powder characteristics and moldability of the dry powder.
(Comparative Example 1)
As a dispersant, 20 kg of 0.1% aqueous solution of polyvinyl alcohol (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name: Gohsenol KH-17) was charged into a 100 L solvent evaporation reactor, and 10 kg of the polymer solution prepared in Production Example 2 was used. Was further introduced. Thereafter, in the same manner as in Example 1, the solvent was evaporated while stirring at 200 rpm using a Max Blend blade, and latex treatment was performed. The average particle diameter of the obtained spherical particles was 210 μm, but the fine particles of 100 microns or less were 12%. The obtained spherical particle slurry was dehydrated or dried in the same manner as in Example 1 to obtain dry spherical polymer particles, and slush molding was performed. Table 1 shows the results of the powder characteristics and moldability of the dry powder.

  Table 1 shows the results of evaluating the angle of repose, apparent specific gravity and ICI flow time using the spherical powders of the present invention obtained in Examples 1 and 2. As can be seen from Table 1, since the spherical powders of the present invention obtained in Examples 1 and 2 and 3 have a smaller angle of repose and a short ICI flow compared to the comparative examples, the powder collapses. It turns out that it is easy to flow. In addition, since the apparent specific gravity is large, when the mold is filled, there are few gaps and the moldability is good.

  As described above, it can be seen that the spherical powder obtained by the production method of the present invention is a spherical powder with good powder characteristics suitable for use in powder slush molding and the like.

It is a figure which shows the measuring method of a repose angle and apparent specific gravity. It is a figure of the funnel-shaped metallic container used for the measurement of ICI flow. It is the figure which showed the metal mold | die used for a moldability evaluation. It is the figure which showed the droplet production | generation apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Plate 2 Nozzle 3 Vibrating partition 4 Side wall 5 Container 6 Liquid inlet 7 Exciter 8 Vibration isolator 9 Liquid column 10 Droplet 11 Chamber 12 Liquid supply port 13 Slurry outlet 14 Container 15 Slurry chamber

Claims (9)

In a method of obtaining polymer spherical particles by heating a polymer solution dissolved in a solvent, water and a water dispersion containing water and a dispersing agent to recover the solvent from the water dispersion, and (1) water dispersion Forming a droplet of a polymer solution dissolved in a solvent in an aqueous solution containing water and a dispersing agent before stirring the solution, and throwing it into an evaporation reactor; (2) water dispersion of the droplet of the polymer solution Heating the liquid with stirring to recover the solvent from the aqueous dispersion to obtain polymer spherical particles; and (3) separating the polymer spherical particles from the aqueous dispersion containing the polymer spherical particles. The manufacturing method of the polymer spherical powder characterized by including a process. While making an aqueous dispersion containing water and a dispersant and a polymer solution dissolved in a solvent simultaneously into a cleaved blade stationary mixer (static mixer), making an aqueous dispersion of droplets of the polymer solution 2. The production according to claim 1, wherein the polymer spherical particle aqueous dispersion is obtained by collecting the solvent by supplying steam to the reactor for performing solvent evaporation and then adding the steam while stirring. Method. A polymer solution dissolved in a solvent is ejected from a nozzle hole into an aqueous dispersion containing water and a dispersant, and a regular vibration disturbance is applied to the liquid to form droplets in the aqueous dispersion. 2. The production according to claim 1, wherein the polymer spherical particle aqueous dispersion is obtained by recovering the solvent by supplying steam to the reactor which performs evaporation and accumulating a predetermined amount and then stirring. Method. The production method according to claim 1, wherein at least one dispersant selected from the group consisting of methylcellulose, polyvinyl alcohol, calcium phosphate, calcium carbonate, and a nonionic surfactant is used as the dispersant. The manufacturing method according to claim 1, wherein the polymer has a glass transition temperature of 30 to 150 ° C. The production method according to claim 5, wherein the polymer is a thermoplastic resin. The method according to claim 6, wherein the thermoplastic resin is selected from a (meth) acrylic polymer, a (meth) acrylic copolymer, and an isobutylene polymer. 8. The production method according to claim 1, wherein the obtained polymer spherical powder has small pores having an inner diameter of 1 to 50% of the particle diameter on the particle surface. A powder for molding an automobile interior skin produced by the production method according to claim 1.

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