JP2023143335A - Method for producing aggregate and method for producing granule - Google Patents

Abstract

To provide a novel method for producing aggregates of polymer fine particles which can provide powder granules having a low fineness ratio.SOLUTION: There is provided a novel method for producing an aggregate which comprises a first contact step of spraying and/or dropping a latex of polymer fine particles in the vertical direction and spraying a coagulant solution in the horizontal direction or a second step of spraying and/or dropping the coagulant solution in the vertical direction and spraying the latex in the horizontal direction, wherein in the second contact step, the horizontal distance between the nozzles is longer than the vertical distance.SELECTED DRAWING: None

Description

The present invention relates to a method for producing an aggregate and a method for producing a powder or granular material.

Powders of polymer fine particles are used as resin modifiers such as impact modifiers. As a method for manufacturing such a powder or granular material, a method has been proposed in which a latex of polymer fine particles is coagulated to form an aggregate, and the aggregate is dried.

As such a method, Patent Document 1 describes a method in which a latex of polymer fine particles containing a thickener is sprayed or dropped into a gas phase containing a coagulant solution in the form of a mist.

JP2017-61645

However, the above-mentioned conventional techniques are not sufficient in terms of the fineness of powder and granules, and there is room for further improvement.

One embodiment of the present invention has been made in view of the above-mentioned problems, and its purpose is to provide a novel method for producing aggregates of polymer fine particles that can provide a powder or granule with a small fineness ratio, and a novel method for producing an aggregate of polymer particles. The objective is to provide a new manufacturing method.

The present inventor has completed the present invention as a result of intensive studies to solve the above problems. That is, one embodiment of the present invention includes the following configuration.
[1] A latex of polymer particles is sprayed and/or dropped vertically from a first nozzle, and a coagulant solution is sprayed horizontally from a second nozzle to form droplets of the latex and the coagulant. A first contacting step of contacting the solution with droplets, or spraying and/or dropping the coagulant solution vertically from the second nozzle, and spraying the latex horizontally from the first nozzle. and a second contacting step of bringing the latex droplets into contact with the coagulant solution droplets, and if the second contacting step is included, the first nozzle and the second nozzle A method for producing an aggregate, wherein a horizontal distance between the first nozzle and the second nozzle is longer than a vertical distance between the first nozzle and the second nozzle.
[2] In the first contacting step and the second contacting step, the latex is The method for producing an aggregate according to [1], wherein the droplets of the coagulant solution are brought into contact with the droplets of the coagulant solution.
[3] Including the first contact step, in the first contact step, the horizontal distance between the first nozzle and the second nozzle is equal to the distance between the first nozzle and the second nozzle. The method for producing an aggregate according to [1] or [2], wherein the distance between the aggregate and the nozzle is longer than the vertical distance between the aggregate and the nozzle.
[4] The aggregate according to any one of [1] to [3], wherein the concentration of the polymer fine particles in the latex is 10% to 55% by weight based on 100% by weight of the latex. Production method.
[5] Any one of [1] to [4], wherein the amount of coagulant sprayed is 1 part by weight to 30 parts by weight based on the total of 100 parts by weight of the amount of sprayed and dropped amount of the polymer fine particles. A method for producing an aggregate as described in .
[6] The method for producing an aggregate according to any one of [1] to [5], wherein the polymer fine particles include an elastic body and a graft portion grafted to the elastic body. .
[7] The method for producing an aggregate according to [6], wherein the elastic body includes one or more selected from the group consisting of diene rubber, (meth)acrylate rubber, and organosiloxane rubber.
[8] The graft portion is derived from one or more monomers selected from the group consisting of aromatic vinyl monomers, vinyl cyan monomers, and (meth)acrylate monomers as structural units. The method for producing an aggregate according to [6] or [7], which is made of a polymer containing a structural unit.
[9] A recovery step of recovering the aggregate obtained by the method for producing an aggregate according to any one of [1] to [8], and a drying step of drying the recovered aggregate, A method for producing a granular material of polymer fine particles, comprising:

According to one aspect of the present invention, it is possible to provide a novel method for producing aggregates of polymer fine particles and a novel method for producing powder or granules, which can provide powder or granules with a low fineness ratio.

An embodiment of the present invention will be described below, but the present invention is not limited thereto. The present invention is not limited to each configuration described below, and various changes can be made within the scope of the claims. Further, embodiments or examples obtained by appropriately combining technical means disclosed in different embodiments or examples are also included in the technical scope of the present invention. Furthermore, new technical features can be formed by combining the technical means disclosed in each embodiment. Note that all academic literature and patent literature described in this specification are incorporated as references in this specification. In addition, unless otherwise specified in this specification, the numerical range "A to B" is intended to be "above A (including A and greater than A) and less than or equal to B (including B and less than B)."

[1. Technical idea of one embodiment of the present invention]
As a method for producing aggregates and granules of polymer fine particles from latex of polymer fine particles (hereinafter sometimes referred to as latex), the latex of polymer fine particles is sprayed and/or dropped into a gas phase. , by bringing the latex droplets of the polymer fine particles into contact with the droplets of the coagulant solution sprayed into the gas phase, the polymer fine particles are aggregated to obtain an aggregate of the polymer fine particles, and the aggregate is dried. A method of obtaining powder or granular material is known.

Patent Document 1 describes that the latex of the polymer fine particles and a coagulant solution are sprayed from a nozzle. Conventionally, in such spraying of latex and coagulant solution, both the latex and coagulant solution were sprayed in a vertical direction, and a two-fluid nozzle was used for spraying the coagulant solution.

In the technique of Patent Document 1, the fine powder ratio of the powder of polymer particles is large, and there is room for further improvement from the viewpoint of the fine powder ratio. Therefore, the present inventor conducted extensive studies in order to provide a new method for producing aggregates of polymer fine particles and a new method for producing powder and granules, which can provide powder and granules with a small fineness ratio.

As a result of intensive studies, the present inventor obtained the following new findings and completed the present invention: (i) Spraying and/or dropping latex of polymer particles in the vertical direction from the first nozzle, It would be surprising if the method for producing an aggregate includes a first contact step of horizontally spraying a coagulant solution from a second nozzle and bringing the latex droplets into contact with the coagulant solution droplets. Preferably, it is possible to provide an aggregate of polymer fine particles that can provide a powder with a low fines ratio; and (ii) the coagulant solution is vertically sprayed and/or dripped from a second nozzle, and a second contacting step of horizontally spraying the latex from the first nozzle to bring the latex droplets into contact with the coagulant solution droplets; Surprisingly, if the method for producing aggregates is such that the horizontal distance between the second nozzle and the second nozzle is longer than the vertical distance between the first nozzle and the second nozzle, fine powder An object of the present invention is to provide an aggregate of fine polymer particles that can provide a powder or granular material with a low ratio.

Although it is not clear why the production method including the first contact step or the second contact step as described above can provide aggregates of polymer fine particles that can provide powder or granules with a small fines ratio, the present invention The inventor speculated as follows: compared to a manufacturing method that does not include a first contacting step or a second contacting step, in a manufacturing method that includes a first contacting step or a second contacting step, each contact In the process, the probability of collision between the latex droplets of the polymer fine particles and the coagulant solution droplets is high, and the contact efficiency between the latex droplets of the polymer fine particles and the coagulant solution droplets is high. Due to the high contact efficiency between the latex droplets of the polymer particles and the coagulant solution droplets, aggregates of the polymer particles are efficiently generated, and the amount of minute components of the aggregates that can cause fine powder is reduced. reduced.
Note that the present invention is not limited to such speculation in any way.

[2. Method for producing aggregate]
A method for producing an aggregate according to an embodiment of the present invention includes spraying and/or dropping latex of polymer particles vertically from a first nozzle, and spraying a coagulant solution horizontally from a second nozzle. a first contacting step of bringing the latex droplets into contact with the coagulant solution droplets, or spraying and/or dropping the coagulant solution vertically from the second nozzle; a second contacting step of spraying the latex horizontally from a first nozzle to bring the droplets of the latex into contact with the droplets of the coagulant solution; , a horizontal distance between the first nozzle and the second nozzle is longer than a vertical distance between the first nozzle and the second nozzle. In this specification, the method for producing an aggregate according to one embodiment of the present invention may be hereinafter referred to as "the present method for producing an aggregate."

Here, in this specification, the latex of polymer fine particles may be simply referred to as "latex", the aggregate of polymer fine particles may be simply referred to as "aggregate", and the method for producing the present aggregate The aggregate of polymer fine particles obtained by the method may be hereinafter referred to as "main aggregate". Further, a powder or granule of polymer fine particles may be simply referred to as a "powder or granule."

In addition, in this specification, "spraying" a liquid (for example, latex or coagulant solution) refers to an outlet of a nozzle that sprays the liquid by applying pressure to the liquid, subjecting it to ultrasonic treatment, or the like. "Dropping" a liquid (for example, latex) is intended to spray (atomized spray) in the form of droplets (microdroplets) that are smaller in diameter than the diameter of the hole. The intention is to spray the liquid as droplets with a droplet diameter comparable to the diameter of the outlet (hole) of the nozzle that sprays the liquid, without any particular treatment. In addition, as in the case of spraying liquid using a two-fluid nozzle, even if the sprayed liquid itself is not pressurized, it is possible to simultaneously spray a substance other than the liquid (e.g. gas) under pressure. When the liquid is sprayed in the form of minute droplets, the liquid is considered to be "sprayed".

Moreover, in this specification, the "vertical direction" intends the direction of gravity, and refers to a direction also referred to as a vertically downward direction. Furthermore, in this specification, "spraying and/or dropping a liquid (for example, latex) in the vertical direction" does not necessarily mean spraying and/or dropping the liquid completely in the vertical direction. As a standard, the liquid may be sprayed and/or dropped in an inclined direction within a range of 15°, 10°, or 5°. That is, in this specification, "spraying and/or dropping in the vertical direction" is a concept that includes such a mode of spraying and/or dropping at an angle with respect to the vertical direction.

Furthermore, in this specification, the term "horizontal direction" refers to a direction perpendicular to the vertical direction. Furthermore, in this specification, "spraying a liquid (for example, a coagulant solution) horizontally" does not necessarily mean spraying the liquid completely horizontally; for example, within 15 degrees with respect to the horizontal direction. , the liquid may be sprayed in an inclined direction within a range of 10° or 5°. That is, "spraying in the horizontal direction" in this specification includes a mode in which the liquid is sprayed at an angle with respect to the horizontal direction. Note that in this specification, the direction in which the liquid is sprayed and/or dropped can also be said to be the direction directly facing the outlet of the nozzle that sprays and/or drops the liquid. In other words, the direction in which the liquid is sprayed and/or dropped can be adjusted by adjusting the direction in which the outlet of the nozzle that sprays and/or drops the liquid faces.

In addition, in this specification, "the vertical distance between the first nozzle and the second nozzle" and "the horizontal distance between the first nozzle and the second nozzle" are as follows. It is a value measured by the method: (1) draw a vertical straight line (first straight line) passing through the center of the outlet (hole) of the first nozzle; (2) draw a straight line in the vertical direction passing through the center of the outlet (hole) of the second nozzle; (3) Draw a straight line (second straight line) in the horizontal direction (perpendicular to the vertical direction) passing through the center of the hole; (3) draw the intersection of the first straight line and the second straight line and the air outlet of the first nozzle; The vertical distance between the center of the first nozzle and the second nozzle is defined as "the vertical distance between the first nozzle and the second nozzle" Let the horizontal distance between the center of the air outlet and the center of the air outlet be the "horizontal distance between the first nozzle and the second nozzle." Note that when there are multiple nozzles whose distances are to be compared (for example, when there are multiple first nozzles and multiple second nozzles), the shortest ( (closer) value is the distance between the nozzles. In addition, in this specification, "the vertical distance between the first nozzle and the second nozzle" may be referred to as "the vertical distance between the first nozzle and the second nozzle", and "the vertical distance between the first nozzle and the second nozzle" may be referred to as "the vertical distance between the first nozzle and the second nozzle". The horizontal distance between the first nozzle and the second nozzle may be referred to as the horizontal distance between the first nozzle and the second nozzle.

Since the present method for producing an aggregate has the above-described structure, it has the advantage of being able to provide an aggregate of polymer fine particles that can provide a granular material with a small fineness ratio. Furthermore, with this method for producing aggregates, it is surprisingly possible to provide aggregates with a high degree of circularity (close to 1), and by drying the aggregates, the degree of circularity is high (close to 1). ) and has the advantage of being able to provide powder and granules with a large bulk specific gravity.

Additionally, the present inventor has surprisingly found that with the present method for producing aggregates, in the droplets obtained by contacting the latex droplets of polymer fine particles with the coagulant solution droplets, We have obtained a new finding that the time required to aggregate the combined fine particles (in other words, the physical distance) can be shortened. The reason for this is not clear, but as mentioned above, the probability of collision between latex droplets of polymer fine particles and coagulant solution droplets is high, and the collision between latex droplets of polymer fine particles and coagulant solution droplets is high. It can be assumed that this is because the contact efficiency is high. Note that the present invention is not limited to such speculation in any way. Therefore, the present method for producing an aggregate also has the advantage that the apparatus used in the production method can be made smaller (in particular, the height can be reduced) compared to the conventional technology.

Hereinafter, the raw materials (components) and equipment used in the present method for producing an aggregate will be explained in detail, and then the steps of the method for producing the present aggregate will be explained.

(2-1. Latex)
As used herein, "latex" refers to a solution containing a solvent and fine polymer particles, in which the fine polymer particles are dispersed in the solvent. "Latex" is a latex containing fine polymer particles, and "latex" can also be said to be a "suspension of fine polymer particles." The solvent for latex is not particularly limited, but includes, for example, water. A latex whose solvent is water is sometimes called an "aqueous latex" and can also be said to be an "aqueous suspension of polymer particles." The polymer fine particles are preferably dispersed in the form of primary particles in the latex solvent.

The concentration of the polymer fine particles in the latex is not particularly limited, but it is preferably 10% to 55% by weight, more preferably 10% to 45% by weight, based on 100% by weight of the latex. More preferably, the amount is 25% to 40% by weight. It is preferable that the concentration of the polymer fine particles in the latex is 10% by weight or more because the bulk specific gravity of the aggregate becomes large. It is preferable that the concentration of the polymer fine particles in the latex is 55% by weight or less because the latex can be smoothly sprayed and/or dripped from a nozzle. Note that the concentration of the polymer fine particles in the latex can be adjusted by appropriately changing the amount of solvent (e.g., water) used in the manufacturing process of the polymer fine particles, the amount of monomer used, etc. can.

The concentration of the polymer fine particles in the latex can be determined by, for example, placing 0.5 g of the latex in a hot air convection dryer at 120°C for 3 hours to evaporate water, and the weight of the residue (solid content) after drying W (g ), divide the obtained value by 0.5 g of the weight of the latex before drying, and multiply the obtained value by 100. The residue after drying, that is, the solid content, mainly contains fine polymer particles, but may also contain components other than fine polymer particles. Therefore, the "concentration of polymer fine particles in latex" calculated by the above method can also be rephrased as "concentration of solid content in latex."

The viscosity of the latex at 25° C. is not particularly limited, but is preferably 10 mPa·s or more, more preferably 15 mPa·s or more, and even more preferably 20 mPa·s or more. Further, the upper limit of the viscosity of the latex at 25° C. is not particularly limited, but is preferably 100 mPa·s or less, more preferably 50 mPa·s or less, and even more preferably 30 mPa·s or less.

When the viscosity of the latex at 25° C. is 10 mPa·s or more, the advantage is that the amount of fine powder produced as a by-product when producing powder or granules from the aggregates obtained by the present method for producing aggregates is easily reduced. have In addition, when the viscosity of the latex at 25° C. is 100 mPa·s or less, the aggregate obtained by the present aggregate manufacturing method can be smoothly sprayed and/or dropped from the nozzle of the device (for example, the first nozzle described below). It has the advantage of being able to In addition, the viscosity of the latex can be determined by changing the solid content concentration in the latex (concentration of polymer particles in the latex), and if the latex contains a thickener, the content of the thickener in the latex, etc. as appropriate. It can be adjusted by

The viscosity of latex can be measured using a viscometer such as Cannon-Fenske, Cannon-Fenske reflux type, Ubbelohde, Brookfield (Type B viscometer) for latex at 25°C. The method for measuring the viscosity of latex will be described in detail in the Examples below.

A latex containing fine polymer particles can be produced by known methods, such as emulsion polymerization of fine polymer particles and a method of suspending fine polymer particles and an emulsifier in a solvent. The emulsion polymerization method for producing fine polymer particles will be described in detail in the section (2-3. Manufacturing method for fine polymer particles) below.

(2-2. Polymer fine particles)
Other aspects of the polymer fine particles are not particularly limited as long as they are fine particles obtained by polymerization.

(graft part)
It is preferable that the polymer fine particles have a graft portion. As used herein, the term "graft portion" refers to a polymer grafted to any polymer. The polymer fine particles having a graft portion can also be called a graft copolymer. That is, it is preferable that the polymer fine particles are a graft copolymer. When the polymer fine particles are a graft copolymer, there is an advantage that the polymer fine particles can exhibit suitable behavior in the present method for producing an aggregate and the method for producing a granular material described below.

The graft portion contains, as a structural unit, a structural unit derived from one or more monomers selected from the group consisting of aromatic vinyl monomers, vinyl cyan monomers, and (meth)acrylate monomers. It is preferably (including) a polymer. The graft portion having the above configuration can play various roles. "Various roles" include, for example, (i) improving the compatibility between the polymer fine particles and the matrix resin, (ii) improving the dispersibility of the polymer fine particles in the matrix resin, and (iii) ) Enable the polymer fine particles to be dispersed in the state of primary particles in a resin composition containing a matrix resin and polymer fine particles (hereinafter also simply referred to as "resin composition"), or a molded or cured product thereof. , etc.

Specific examples of aromatic vinyl monomers include styrene, α-methylstyrene, p-methylstyrene, and divinylbenzene.

Specific examples of the vinyl cyan monomer include acrylonitrile and methacrylonitrile.

Specific examples of the (meth)acrylate monomer include methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, hydroxyethyl (meth)acrylate, and hydroxybutyl (meth)acrylate. (Meth)acrylate as used herein means acrylate and/or methacrylate.

Only one type of monomer selected from the group consisting of aromatic vinyl monomers, vinyl cyan monomers, and (meth)acrylate monomers may be used, Two or more types may be used in combination.

The graft portion includes, as structural units, a structural unit derived from an aromatic vinyl monomer, a structural unit derived from a vinyl cyan monomer, and a structural unit derived from a (meth)acrylate monomer. In the weight%, it is preferably contained in 10 to 95% by weight, more preferably 30 to 92% by weight, further preferably contained in 50 to 90% by weight, particularly preferably contained in 60 to 87% by weight, and particularly preferably contained in 70 to 92% by weight. Most preferably, it contains 85% by weight.

It is preferable that the graft portion contains, as a structural unit, a structural unit derived from a monomer having a reactive group. The monomer having the reactive group includes an epoxy group, an oxetane group, a hydroxyl group, an amino group, an imide group, a carboxylic acid group, a carboxylic acid anhydride group, a cyclic ester, a cyclic amide, a benzoxazine group, and a cyanate ester group. The monomer preferably has one or more reactive groups selected from the group consisting of epoxy groups, hydroxyl groups, and carboxylic acid groups. A monomer is more preferable, and a monomer having an epoxy group is most preferable. According to the above configuration, the graft portion of the polymer fine particles and the matrix resin can be chemically bonded in the resin composition. Thereby, a good dispersion state of the polymer particles can be maintained in the resin composition or in the molded product or cured product thereof without agglomerating the polymer particles.

Specific examples of monomers having epoxy groups include glycidyl group-containing vinyl monomers such as glycidyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate glycidyl ether, and allyl glycidyl ether.

Specific examples of monomers having hydroxyl groups include (i) hydroxy linear alkyl (meth)acrylate such as 2-hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate; Acrylates (especially hydroxy linear C1-6 alkyl (meth)acrylates); (ii) caprolactone-modified hydroxy (meth)acrylates; (iii) methyl α-(hydroxymethyl)acrylate, ethyl α-(hydroxymethyl)acrylate (iv) Mono(meth)acrylates of polyester diols (especially saturated polyester diols) obtained from dihydric carboxylic acids (phthalic acid, etc.) and dihydric alcohols (propylene glycol, etc.), etc. Examples include hydroxyl group-containing (meth)acrylates.

Specific examples of monomers having carboxylic acid groups include monocarboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid, and dicarboxylic acids such as maleic acid, fumaric acid, and itaconic acid. As the monomer having a carboxylic acid group, the monocarboxylic acids mentioned above are preferably used.

The monomers having the above-mentioned reactive groups may be used alone or in combination of two or more.

The graft portion preferably contains 0.5% to 90.0% by weight, and preferably 1.0% to 50.0% by weight, of structural units derived from monomers having reactive groups based on 100% by weight of the grafted portion. It is more preferable to contain 0% by weight, even more preferably to contain 2.0% to 35.0% by weight, and particularly preferably to contain 3.0% to 20.0% by weight. When the grafted part contains (i) 0.5% by weight or more of a structural unit derived from a monomer having a reactive group in 100% by weight of the grafted part, the resulting resin composition has sufficient impact resistance. (ii) When containing 90.0% by weight or less, the resulting resin composition can provide a molded product or cured product having sufficient impact resistance. It has the advantage that the resin composition has good storage stability.

The structural unit derived from a monomer having a reactive group is preferably contained in the graft portion, and more preferably contained only in the graft portion.

The graft portion may contain, as a structural unit, a structural unit derived from a polyfunctional monomer. When the graft portion contains a structural unit derived from a polyfunctional monomer, (i) swelling of the polymer particles in the resin composition can be prevented, and (ii) the viscosity of the resin composition is reduced. Therefore, the resin composition tends to have better handling properties, and (iii) the dispersibility of the polymer fine particles in the matrix resin is improved.

When the graft part does not contain a structural unit derived from a polyfunctional monomer, the resulting resin composition has better toughness and It is possible to provide a molded product or a cured product with better impact resistance.

A polyfunctional monomer can also be said to be a monomer having two or more radically polymerizable reactive groups within the same molecule. The radically polymerizable reactive group is preferably a carbon-carbon double bond. Examples of polyfunctional monomers include (meth)acrylates having ethylenically unsaturated double bonds, such as allyl alkyl (meth) acrylates and allyloxyalkyl (meth) acrylates, but do not include butadiene. be done. Monomers having two (meth)acrylic groups include ethylene glycol di(meth)acrylate, butylene glycol di(meth)acrylate, butanediol di(meth)acrylate, hexanediol di(meth)acrylate, and cyclohexanedimethanol. Di(meth)acrylates and polyethylene glycol di(meth)acrylates are mentioned. Examples of the polyethylene glycol di(meth)acrylates include triethylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol (600) di(meth)acrylate, etc. is exemplified. In addition, monomers having three (meth)acrylic groups include alkoxylated trimethylolpropane tri(meth)acrylates, glycerolpropoxytri(meth)acrylate, pentaerythritol tri(meth)acrylate, tris(2-hydroxy Examples include ethyl)isocyanurate tri(meth)acrylate. Examples of the alkoxylated trimethylolpropane tri(meth)acrylates include trimethylolpropane tri(meth)acrylate, trimethylolpropane triethoxytri(meth)acrylate, and the like. Furthermore, examples of the monomer having four (meth)acrylic groups include pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, and the like. Furthermore, examples of the monomer having five (meth)acrylic groups include dipentaerythritol penta(meth)acrylate. Furthermore, examples of the monomer having six (meth)acrylic groups include ditrimethylolpropane hexa(meth)acrylate. Polyfunctional monomers also include diallyl phthalate, triallyl cyanurate, triallyl isocyanurate, divinylbenzene, and the like.

Among the above-mentioned polyfunctional monomers, polyfunctional monomers that can be preferably used for polymerization of the graft portion include allyl methacrylate, ethylene glycol di(meth)acrylate, butylene glycol di(meth)acrylate, and butanediol. Di(meth)acrylate, hexanediol di(meth)acrylate, cyclohexanedimethanol di(meth)acrylate, and polyethylene glycol di(meth)acrylates. Only one type of these polyfunctional monomers may be used, or two or more types may be used in combination.

The graft portion preferably contains 1% to 20% by weight, more preferably 5% to 15% by weight, of a structural unit derived from a polyfunctional monomer based on 100% by weight of the grafted portion.

In the polymerization of the graft portion, the above-mentioned monomers may be used alone or in combination of two or more. Moreover, the graft portion may contain, as a structural unit, a structural unit derived from another monomer in addition to the structural unit derived from the above-mentioned monomer.

Further, the graft portion is preferably a polymer graft-bonded to an elastic body, which will be described later.

(Glass transition temperature of graft part)
The glass transition temperature of the graft portion is not particularly limited, but is preferably 0°C or higher, more preferably 30°C or higher, more preferably 50°C or higher, and even more preferably 60°C or higher. Polymer fine particles having a glass transition temperature of 60° C. or higher at the graft portion can be said to be a hard grade. When using a hard grade, there is also the advantage that the amount of hard inelastic polymer latex used can be reduced in the heat treatment step and drying step described later. The glass transition temperature of the graft portion may be 65°C or higher, 70°C or higher, 80°C or higher, 90°C or higher, or 100°C or higher. Good too. The upper limit of the glass transition temperature of the graft portion is not particularly limited, but is preferably 190°C or lower, more preferably 160°C or lower, more preferably 140°C or lower, and even more preferably 120°C or lower.

The Tg of the graft portion can be determined depending on the composition of the structural units contained in the graft portion. In other words, by changing the composition of the monomers used when producing (polymerizing) the graft part, the Tg of the resulting graft part can be adjusted.

When the graft part is a copolymer of two or more types of monomers and the monomer used for the production (polymerization) of the graft part is known, the glass transition temperature Tg of the graft part is FOX shown below. It can be calculated using the formula (Formula 1).

1/Tg=w1/Tg1+w2/Tg2+...+wn/Tgn (Formula 1)
Here, Tg1, Tg2, ..., Tgn are the Tg of the homopolymer of components 1, 2, ..., n constituting the graft part (i.e., monomers used in the production of the graft part), respectively. (K), w1, w2, ..., wn are the weight fractions of components 1, 2, ..., n constituting the graft part (i.e. monomers used in the production of the graft part), respectively. be. Further, for the Tg of the homopolymer, for example, the numerical value described in Polymer Handbook Fourth Edition (edited by J. Brandup et al., Jphn Wiley & Sons, Inc.) can be used. Further, in the case of a new polymer, the peak temperature of loss tangent (tan δ) in a viscoelasticity measurement method (shear method, measurement frequency: 1 Hz) may be employed as Tg.

When the monomer used to manufacture (polymerize) the graft portion is unknown, the Tg of the graft portion can be obtained by measuring viscoelasticity using a flat plate made of polymer fine particles. Specifically, Tg can be measured as follows: (1) A dynamic viscoelasticity measurement device (for example, DVA-200 manufactured by IT Keizai Control Co., Ltd.) is used for a flat plate made of polymer fine particles. Then, dynamic viscoelasticity is measured under tensile conditions to obtain a graph of tan δ; (2) Regarding the obtained graph of tan δ, the peak temperature of tan δ is taken as the glass transition temperature. Here, in the graph of tan δ, when a plurality of peaks are obtained, the highest peak temperature is taken as the glass transition temperature of the graft portion.

(Modified example of graft part)
In one embodiment of the invention, the graft portion may consist of only one type of graft portion having constitutional units of the same composition. In one embodiment of the present invention, the graft portion may be composed of multiple types of graft portions each having a different composition of structural units.

When the polymer fine particles are a multistage polymer, the graft portion may cover at least a portion of any polymer (for example, an elastic body described below), or may cover the entirety of any polymer. When the polymer fine particles are a multistage polymer, a part of the graft portion may be inside any polymer. Preferably, at least a portion of the graft portion covers at least a portion of the elastic body. In other words, at least a portion of the graft portion is preferably present on the outermost side of the polymer fine particles.

When the polymer fine particles are a multistage polymer, an arbitrary polymer (for example, an elastic body described below) and a graft portion may form a layered structure. For example, an embodiment in which the elastic body forms the innermost layer (also referred to as a core layer) and a layer of the graft portion is formed as the outermost layer (also referred to as a shell layer) on the outside of the elastic body is also an aspect of the present invention. be. A structure in which the elastic body is the core layer and the graft portion is the shell layer can also be called a core-shell structure. In this way, polymer particles in which the elastic body and the graft portion form a layered structure (core-shell structure) can also be called a multilayer polymer or a core-shell polymer. That is, in one embodiment of the present invention, the polymer fine particles may be a multistage polymer and/or a multilayer polymer or a core-shell polymer. However, the polymer fine particles are not limited to the above configuration as long as they have a graft portion.

(elastic body)
It is preferable that the polymer fine particles further include an elastic body. The above-mentioned graft portion is preferably a polymer graft-bonded to the elastic body. That is, it is more preferable that the polymer fine particles are a rubber-containing graft copolymer having an elastic body and a graft portion grafted to the elastic body. Hereinafter, one embodiment of the present invention will be described by taking as an example the case where the polymer fine particles are a rubber-containing graft copolymer.

The elastic body preferably contains one or more selected from the group consisting of diene rubber, (meth)acrylate rubber, and organosiloxane rubber. The elastic body may contain natural rubber in addition to the above-mentioned rubber. The elastic body can also be referred to as an elastic part or rubber particles.

A case where the elastic body contains a diene rubber (case A) will be explained. In case A, the resulting resin composition can provide a molded or cured product with excellent toughness and impact resistance. A molded product or cured product with excellent toughness and/or impact resistance can also be said to be a molded product or cured product with excellent durability.

The diene rubber is an elastic body containing, as a constitutional unit, a constitutional unit derived from a diene monomer. The diene monomer can also be referred to as a conjugated diene monomer. In case A, the diene rubber contains 50 to 100% by weight of structural units derived from diene monomers out of 100% by weight of structural units, and other than diene monomers copolymerizable with diene monomers. It may contain 0 to 50% by weight of structural units derived from vinyl monomers. In case A, the diene rubber may contain, as a structural unit, a structural unit derived from a (meth)acrylate monomer in a smaller amount than the structural unit derived from a diene monomer.

Examples of the diene monomer include 1,3-butadiene, isoprene (2-methyl-1,3-butadiene), and 2-chloro-1,3-butadiene. These diene monomers may be used alone or in combination of two or more.

Examples of vinyl monomers other than diene monomers (hereinafter also referred to as vinyl monomer A) that can be copolymerized with diene monomers include styrene, α-methylstyrene, and monochlorostyrene. , vinyl arenes such as dichlorostyrene; vinyl carboxylic acids such as acrylic acid and methacrylic acid; vinyl cyanates such as acrylonitrile and methacrylonitrile; vinyl halides such as vinyl chloride, vinyl bromide, and chloroprene; vinyl acetate; ethylene , alkenes such as propylene, butylene, and isobutylene; and polyfunctional monomers such as diallyl phthalate, triallyl cyanurate, triallyl isocyanurate, and divinylbenzene. The above-mentioned vinyl monomer A may be used alone or in combination of two or more types. Among the vinyl monomers A mentioned above, styrene is particularly preferred. In addition, in the diene rubber in case A, the structural unit derived from vinyl monomer A is an optional component. In case A, the diene rubber may be composed only of structural units derived from diene monomers.

In case A, the diene rubber is butadiene rubber (also referred to as polybutadiene rubber) consisting of constitutional units derived from 1,3-butadiene, or butadiene rubber which is a copolymer of 1,3-butadiene and styrene. Styrene rubber (also referred to as polystyrene-butadiene) is preferred, and butadiene rubber is more preferred. According to the above configuration, the desired effect due to the polymer fine particles containing the diene rubber can be better exhibited. Further, butadiene-styrene rubber is more preferable in that the transparency of the obtained molded product or cured product can be increased by adjusting the refractive index.

A case (case B) in which the elastic body contains (meth)acrylate rubber will be explained. In case B, the combination of various monomers allows a wide range of polymer designs for the elastomer.

The (meth)acrylate rubber is an elastic body containing, as a structural unit, a structural unit derived from a (meth)acrylate monomer. In case B, the (meth)acrylate rubber contains 50 to 100% by weight of the structural units derived from the (meth)acrylate monomer out of 100% by weight of the structural units, and co-contains the (meth)acrylate monomer with the structural units derived from the (meth)acrylate monomer. It may contain 0 to 50% by weight of structural units derived from vinyl monomers other than polymerizable (meth)acrylate monomers. In case B, the (meth)acrylate rubber may contain, as a structural unit, a structural unit derived from a diene monomer in a smaller amount than the structural unit derived from a (meth)acrylate monomer. good.

Examples of (meth)acrylate monomers include methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, and dodecyl (meth)acrylate. , stearyl (meth)acrylate, behenyl (meth)acrylate; aromatic ring-containing (meth)acrylates such as phenoxyethyl (meth)acrylate, benzyl (meth)acrylate; 2-hydroxyethyl (meth)acrylate; ) acrylate, hydroxyalkyl (meth)acrylates such as 4-hydroxybutyl (meth)acrylate; glycidyl (meth)acrylates such as glycidyl (meth)acrylate, glycidyl alkyl (meth)acrylate; alkoxyalkyl (meth)acrylates; Allyl alkyl (meth)acrylates such as allyl (meth)acrylate and allyl alkyl (meth)acrylate; monoethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, etc. Examples include polyfunctional (meth)acrylates. These (meth)acrylate monomers may be used alone or in combination of two or more. Among these (meth)acrylate monomers, ethyl (meth)acrylate, butyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate are preferred, and butyl (meth)acrylate is more preferred.

In case B, the (meth)acrylate rubber is 1 selected from the group consisting of methyl (meth)acrylate rubber, ethyl (meth)acrylate rubber, butyl (meth)acrylate rubber, and 2-ethylhexyl (meth)acrylate rubber. It is preferable that the rubber is at least 100% methyl (meth)acrylate rubber, and methyl (meth)acrylate rubber and butyl (meth)acrylate rubber are more preferable. Methyl (meth)acrylate rubber is a rubber consisting of constitutional units derived from methyl (meth)acrylate, and ethyl (meth)acrylate rubber is a rubber consisting of constitutional units derived from ethyl (meth)acrylate. ) Acrylate rubber is a rubber consisting of constitutional units derived from butyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate rubber is a rubber consisting of constitutional units derived from 2-ethylhexyl (meth)acrylate. According to this configuration, since the glass transition temperature (Tg) of the elastic body is lowered, polymer fine particles and resin compositions with lower Tg can be obtained. As a result, (i) the resulting resin composition can provide a molded or cured product with excellent toughness, and (ii) the viscosity of the resin composition can be lowered.

Vinyl monomers other than (meth)acrylate monomers that can be copolymerized with (meth)acrylate monomers (hereinafter also referred to as vinyl monomer B) include the vinyl monomers mentioned above. Examples include the monomers listed in Form A. Only one type of vinyl monomer B may be used, or two or more types may be used in combination. Among the vinyl monomers B, styrene is particularly preferred. In the (meth)acrylate rubber in case B, the structural unit derived from vinyl monomer B is an optional component. In case B, the (meth)acrylate rubber may be composed only of structural units derived from (meth)acrylate monomers.

A case where the elastic body contains an organosiloxane rubber (case C) will be explained. In case C, the resulting resin composition can provide a molded or cured product that has sufficient heat resistance and has excellent impact resistance at low temperatures.

Examples of the organosiloxane rubber include (i) a rubber composed of alkyl or aryl di-substituted silyloxy units such as (i) dimethylsilyloxy, diethylsilyloxy, methylphenylsilyloxy, diphenylsilyloxy, dimethylsilyloxy-diphenylsilyloxy; Organosiloxane-based polymers, (ii) organosiloxane-based polymers composed of alkyl or aryl monosubstituted silyloxy units, such as organohydrogensilyloxy in which some of the alkyls in the side chains are substituted with hydrogen atoms. It will be done. These organosiloxane polymers may be used alone or in combination of two or more.

In this specification, a polymer composed of dimethylsilyloxy units is referred to as dimethylsilyloxy rubber, a polymer composed of methylphenylsilyloxy units is referred to as methylphenylsilyloxy rubber, and a polymer composed of dimethylsilyloxy units and diphenylsilyl A polymer composed of oxy units is called dimethylsilyloxy-diphenylsilyloxy rubber. In case C, as the organosiloxane rubber, (i) dimethylsilyloxy rubber, methylphenylsilyl is used because the resin composition containing the obtained powder can provide a molded product or cured product with excellent heat resistance. It is preferably one or more selected from the group consisting of oxy rubber and dimethylsilyloxy-diphenylsilyloxy rubber, and (ii) dimethylsilyloxy rubber is preferred because it is easily available and economical. More preferred.

In case C, the polymer fine particles preferably contain 80% by weight or more of organosiloxane rubber, more preferably 90% by weight or more, based on 100% by weight of the elastic body contained in the polymer fine particles. preferable. According to the above configuration, the resin composition obtained can provide a molded article or a cured product having excellent heat resistance.

The elastic body may further contain an elastic body other than diene rubber, (meth)acrylate rubber, and organosiloxane rubber. Examples of elastic bodies other than diene rubber, (meth)acrylate rubber, and organosiloxane rubber include natural rubber.

In one embodiment of the present invention, the elastic body includes butadiene rubber, butadiene-styrene rubber, butadiene-(meth)acrylate rubber, ethyl (meth)acrylate rubber, butyl (meth)acrylate rubber, and 2-ethylhexyl (meth)acrylate rubber. , dimethylsilyloxy rubber, methylphenylsilyloxy rubber, and dimethylsilyloxy-diphenylsilyloxy rubber, preferably one or more selected from the group consisting of butadiene rubber, butadiene-styrene rubber, butyl (meth)acrylate. More preferably, it is one or more selected from the group consisting of rubber and dimethylsilyloxy rubber.

(Crosslinked structure of elastic body)
From the viewpoint of maintaining dispersion stability of the polymer fine particles in the thermosetting resin, it is preferable that a crosslinked structure is introduced into the elastic body. As a method for introducing a crosslinked structure into an elastic body, commonly used methods can be employed, and examples include the following method. That is, in the production of an elastic body, there is a method in which a crosslinkable monomer such as a polyfunctional monomer and/or a mercapto group-containing compound is mixed with a monomer that can constitute the elastic body, and then polymerized. . In this specification, producing a polymer such as an elastomer is also referred to as polymerizing the polymer.

In addition, as a method for introducing a crosslinked structure into organosiloxane rubber, the following method may be mentioned: (A) When polymerizing organosiloxane rubber, a polyfunctional alkoxysilane compound and other materials are combined. (B) A method in which a reactive group (for example, (i) a mercapto group and (ii) a reactive vinyl group, etc.) is introduced into an organosiloxane rubber, and then the resulting reaction product is (i) A method of adding an organic peroxide or (ii) a polymerizable vinyl monomer to cause a radical reaction, or (C) a method of adding a polyfunctional monomer when polymerizing an organosiloxane rubber. and/or a method in which a crosslinkable monomer such as a mercapto group-containing compound is mixed with other materials and then polymerized.

Examples of the polyfunctional monomer include the polyfunctional monomers exemplified in the above-mentioned section (grafting part). Among these polyfunctional monomers, allyl methacrylate, ethylene glycol di(meth)acrylate, butylene glycol di(meth)acrylate ( Examples include 1,3-butylene glycol dimethacrylate), butanediol di(meth)acrylate, hexanediol di(meth)acrylate, cyclohexanedimethanol di(meth)acrylate, and polyethylene glycol di(meth)acrylates. . Only one type of these polyfunctional monomers may be used, or two or more types may be used in combination.

(Glass transition temperature of elastic body)
The glass transition temperature of the elastic body is preferably 80°C or lower, more preferably 70°C or lower, more preferably 60°C or lower, more preferably 50°C or lower, more preferably 40°C or lower, more preferably 30°C or lower, and 20°C or lower. C. or less is more preferable, 10.degree. C. or less is more preferable, and 0.degree. C. or less is more preferable. The glass transition temperature of the elastic body may be -10°C or lower, -20°C or lower, -40°C or lower, -45°C or lower, -50°C or lower, -55°C or lower, -60°C or lower, -65°C or lower, -70°C or lower, -75°C or lower, -80°C or lower, -85°C or lower, -90°C or lower, - The temperature may be 95°C or lower, or -100°C or lower. In this specification, "glass transition temperature" may be referred to as "Tg". According to this configuration, it is possible to obtain polymer fine particles having a low Tg and a resin composition having a low Tg. As a result, the resulting resin composition can provide a molded or cured product with excellent toughness. Moreover, according to the configuration, the viscosity of the resulting resin composition can be lowered.

The glass transition temperature (Tg) of the elastic body can be calculated using the above-mentioned FOX formula (Equation 1), except that "the graft portion of the polymer fine particles" is replaced with "the elastic body of the polymer fine particles."

When the monomer used in the production (polymerization) of the elastic body is unknown, the Tg of the elastic body can be obtained by measuring viscoelasticity using a flat plate made of fine polymer particles. Specifically, Tg can be measured as follows: (1) A dynamic viscoelasticity measurement device (for example, DVA-200 manufactured by IT Keizai Control Co., Ltd.) is used for a flat plate made of polymer fine particles. Then, dynamic viscoelasticity is measured under tensile conditions to obtain a graph of tan δ; (2) Regarding the obtained graph of tan δ, the peak temperature of tan δ is taken as the glass transition temperature. Here, in the graph of tan δ, when a plurality of peaks are obtained, the lowest peak temperature is taken as the glass transition temperature of the elastic body.

On the other hand, the Tg of the elastic body is The temperature is preferably higher than 0°C, more preferably 20°C or higher, even more preferably 50°C or higher, particularly preferably 80°C or higher, and most preferably 120°C or higher.

The Tg of the elastic body can be determined by the composition of the structural units contained in the elastic body. In other words, by changing the composition of the monomers used when producing (polymerizing) the elastic body, the Tg of the resulting elastic body can be adjusted.

Here, when a homopolymer is obtained by polymerizing only one type of monomer, the group of monomers that provides a homopolymer having a Tg larger than 0°C is defined as monomer group a. . Further, when a homopolymer is obtained by polymerizing only one type of monomer, a group of monomers that provides a homopolymer having a Tg of less than 0° C. is referred to as monomer group b. 50 to 100% by weight (more preferably 65 to 99% by weight) of structural units derived from at least one monomer selected from monomer group a, and at least one selected from monomer group b. An elastic body containing 0 to 50% by weight (more preferably 1 to 35% by weight) of structural units derived from one type of monomer is referred to as elastic body G. The elastic body G has a Tg greater than 0°C. Further, when the elastic body includes the elastic body G, the resulting resin composition can provide a molded body or a cured product having sufficient rigidity.

Even when the Tg of the elastic body is higher than 0° C., it is preferable that a crosslinked structure is introduced into the elastic body. Examples of the method for introducing the crosslinked structure include the methods described above.

Examples of monomers that may be included in the monomer group a include, but are not limited to, unsubstituted vinyl aromatic compounds such as styrene and 2-vinylnaphthalene; vinyl substituted compounds such as α-methylstyrene; Aromatic compounds; ring alkylated vinyl such as 3-methylstyrene, 4-methylstyrene, 2,4-dimethylstyrene, 2,5-dimethylstyrene, 3,5-dimethylstyrene, 2,4,6-trimethylstyrene, etc. Aromatic compounds; Ring alkoxylated vinyl aromatic compounds such as 4-methoxystyrene and 4-ethoxystyrene; Ring halogenated vinyl aromatic compounds such as 2-chlorostyrene and 3-chlorostyrene; 4-acetoxystyrene, etc. ring ester substituted vinyl aromatic compounds; ring hydroxylated vinyl aromatic compounds such as 4-hydroxystyrene; vinyl esters such as vinyl benzoate and vinyl cyclohexanoate; vinyl halides such as vinyl chloride; acenaphthalene , aromatic monomers such as indene; alkyl methacrylates such as methyl methacrylate, ethyl methacrylate, and isopropyl methacrylate; aromatic methacrylates such as phenyl methacrylate; methacrylates such as isobornyl methacrylate and trimethylsilyl methacrylate; Examples include methacrylic monomers including methacrylic acid derivatives; certain acrylic esters such as isobornyl acrylate and tert-butyl acrylate; acrylic monomers including acrylic acid derivatives such as acrylonitrile; and the like. Further, monomers that can be included in the monomer group a include acrylamide, isopropylacrylamide, N-vinylpyrrolidone, isobornyl methacrylate, dicyclopentanyl methacrylate, 2-methyl-2-adamantyl methacrylate, 1- Examples include monomers that can provide a homopolymer having a Tg of 120° C. or higher, such as adamantyl acrylate and 1-adamantyl methacrylate. These monomers a may be used alone or in combination of two or more.

Examples of the monomer b include ethyl acrylate, butyl acrylate (also known as butyl acrylate), 2-ethylhexyl acrylate, octyl (meth)acrylate, dodecyl (meth)acrylate, 2-hydroxyethyl acrylate, 4-hydroxybutyl acrylate, etc. can be mentioned. These monomers b may be used alone or in combination of two or more. Among these monomers b, particularly preferred are ethyl acrylate, butyl acrylate, and 2-ethylhexyl acrylate.

(Volume average particle diameter of elastic body)
The volume average particle diameter of the elastic body is preferably 0.03 μm to 50.00 μm, more preferably 0.05 μm to 10.00 μm, more preferably 0.08 μm to 2.00 μm, and even more preferably 0.10 μm to 1.00 μm. It is preferably 0.10 μm to 0.80 μm, even more preferably 0.10 μm to 0.50 μm. When the volume average particle diameter of the elastic body is (i) 0.03 μm or more, it is possible to stably obtain an elastic body having a desired volume average particle diameter, and (ii) when it is 50.00 μm or less, the elastic body can be stably obtained. The heat resistance and impact resistance of the molded product or cured product obtained are improved. The volume average particle diameter of the elastic body can be measured using a dynamic light scattering particle size distribution measuring device or the like using an aqueous latex containing the elastic body as a sample. The method for measuring the volume average particle diameter of the elastic body will be described in detail in the Examples below.

(Ratio of elastic body)
The proportion of the elastic body in the polymer fine particles is preferably 40 to 97% by weight, more preferably 60 to 95% by weight, and even more preferably 70 to 93% by weight, based on 100% by weight of the entire fine polymer particles. When the proportion of the elastic body is (i) 40% by weight or more, the resulting resin composition can provide a molded product or cured product with excellent toughness and impact resistance, and (ii) 97% by weight. If it is below, the polymer fine particles do not aggregate easily, so the resin composition does not have high viscosity, and as a result, the resulting resin composition can be easily handled.

(Example of modification of elastic body)
In one embodiment of the present invention, the "elastic body" of the polymer fine particles may consist of only one type of elastic body having the same composition of constituent units. In this case, the "elastic body" of the polymer fine particles is one type selected from the group consisting of diene rubber, (meth)acrylate rubber, and organosiloxane rubber.

In one embodiment of the present invention, the "elastic body" of the polymer fine particles may be composed of a plurality of types of elastic bodies each having a different composition of constituent units. In this case, the "elastic body" of the polymer fine particles may be two or more types selected from the group consisting of diene rubber, (meth)acrylate rubber, and organosiloxane rubber. Further, in this case, the "elastic body" of the polymer fine particles may be one type selected from the group consisting of diene rubber, (meth)acrylate rubber, and organosiloxane rubber. In other words, the "elastic body" of the polymer fine particles may be a plurality of types of diene rubber, (meth)acrylate rubber, or organosiloxane rubber, each having a different composition of constituent units.

In one embodiment of the present invention, a case will be described in which the "elastic body" of the polymer fine particles is composed of a plurality of types of elastic bodies each having a different composition of constituent units. In this case, the plurality of types of elastic bodies are respectively referred to as elastic body ₁ , elastic body ₂ , . . . , and elastic body _n . Here, n is an integer of 2 or more. The "elastic body" of the polymer fine particles may include a composite of separately polymerized elastic body ₁ , elastic body ₂ , . . . , and elastic body _n . The "elastic body" of the polymer fine particles may include one elastic body obtained by polymerizing each of elastic body ₁ , elastic body ₂ , . . . , and elastic body _n in order. The process of sequentially polymerizing a plurality of elastic bodies (polymers) in this manner is also referred to as multistage polymerization. One elastic body obtained by multistage polymerization of multiple types of elastic bodies is also referred to as a multistage polymerized elastic body. The method for producing the multistage polymerized elastic body will be described in detail later.

A multistage polymerized elastic body consisting of elastic body ₁ , elastic body ₂ , . . . , and elastic body _n will be explained. In the multi-stage polymerized elastic body, the elastic body _n may cover at least a portion of the elastic body _n-1 , or may cover the entire elastic body _n-1 . In the multistage polymerized elastic body, a part of the elastic body _n may enter inside the elastic body _n-1 .

In the multistage polymerized elastic body, each of the plurality of elastic bodies may form a layered structure. For example, when the multi-stage polymerized elastic body consists of elastic body ₁ , elastic body ₂ , and elastic body ₃ , elastic body ₁ forms the innermost layer, a layer of elastic body ₂ is formed outside of elastic body ₁ , and An aspect in which the layer of elastic body ₃ is formed as the outermost layer of the elastic body outside the layer of elastic body ₂ is also one aspect of the present invention. In this way, a multistage polymerized elastic body in which each of a plurality of elastic bodies forms a layered structure can also be called a multilayer elastic body. That is, in one embodiment of the present invention, the "elastic body" of the polymer fine particles includes (i) a composite of multiple types of elastic bodies, (ii) a multistage polymerized elastic body, and/or (iii) a multilayer elastic body. It's okay to stay.

(Surface crosslinked polymer)
It is preferable that the rubber-containing graft copolymer further includes a surface crosslinked polymer in addition to the elastic body and the graft portion grafted to the elastic body. In other words, it is preferable that the polymer fine particles further include a surface-crosslinked polymer in addition to the elastic body and the graft portion grafted to the elastic body. Hereinafter, one embodiment of the present invention will be described, taking as an example a case where the polymer fine particles (for example, a rubber-containing graft copolymer) further include a surface crosslinked polymer. In this case, (i) the blocking resistance can be improved in the production of polymer fine particles, and (ii) the dispersibility of the polymer fine particles in the thermosetting resin becomes better. These reasons are not particularly limited, but can be assumed to be as follows: By covering at least a portion of the elastic body with the surface crosslinked polymer, the exposure of the elastic body portion of the polymer fine particles is reduced, and as a result, Since the elastic bodies are less likely to stick to each other, the dispersibility of the polymer fine particles is improved.

When the polymer fine particles have a surface crosslinked polymer, they may also have the following effects: (i) the effect of lowering the viscosity of the present resin composition, (ii) the effect of increasing the crosslinking density in the elastic body, and (iii) ) The effect of increasing the graft efficiency of the graft section. The crosslinking density in an elastic body refers to the number of crosslinked structures in the entire elastic body.

The surface crosslinked polymer contains, as structural units, 30 to 100% by weight of structural units derived from polyfunctional monomers and 0 to 70% by weight of structural units derived from other vinyl monomers, totaling 100% by weight. It consists of a polymer containing % by weight.

The polyfunctional monomers that can be used in the polymerization of the surface-crosslinked polymer include the same monomers as the polyfunctional monomers described above. Among these polyfunctional monomers, polyfunctional monomers that can be preferably used for polymerization of surface crosslinked polymers include allyl methacrylate, ethylene glycol di(meth)acrylate, butylene glycol di(meth)acrylate (e.g. (1,3-butylene glycol dimethacrylate, etc.), butanediol di(meth)acrylate, hexanediol di(meth)acrylate, cyclohexanedimethanol di(meth)acrylate, and polyethylene glycol di(meth)acrylates. Only one type of these polyfunctional monomers may be used, or two or more types may be used in combination.

The polymeric microparticles may include surface crosslinked polymers that are polymerized independently of the polymerization of the rubber-containing graft copolymer, or surface crosslinked polymers that are polymerized together with the rubber-containing graft copolymer. It's okay to stay. The polymer fine particles may be a multistage polymer obtained by performing multistage polymerization of an elastic body, a surface crosslinked polymer, and a graft portion in this order. In any of these embodiments, the surface crosslinked polymer may cover at least a portion of the elastic body.

The surface crosslinked polymer can also be considered as part of the elastic body. In other words, the surface crosslinked polymer can be regarded as a part of the rubber-containing graft copolymer, and can also be said to be a surface crosslinked polymer portion. When the polymer fine particles include a surface-crosslinked polymer, the graft portion may be (i) graft-bonded to an elastic body other than the surface-crosslinked polymer, and (ii) graft-bonded to the surface-crosslinked polymer. (iii) It may be graft-bonded to both the elastic body other than the surface-crosslinked polymer and the surface-crosslinked polymer. When the polymer fine particles include a surface-crosslinked polymer, the above-mentioned volume average particle diameter of the elastic body is intended to be the volume average particle diameter of the elastic body containing the surface-crosslinked polymer.

A case (case D) in which the polymer fine particles are a multistage polymer obtained by performing multistage polymerization of an elastic body, a surface crosslinked polymer, and a graft portion in this order will be described. In case D, the surface crosslinked polymer may cover a portion of the elastic body or may cover the entire elastic body. In case D, a part of the surface crosslinked polymer may have entered the inside of the elastic body. In case D, the graft portion may cover a portion of the surface-crosslinked polymer or may cover the entire surface-crosslinked polymer. In case D, a part of the graft portion may be inside the surface crosslinked polymer. In case D, the elastic body, surface crosslinked polymer, and graft portion may have a layered structure. For example, the elastic body is the innermost layer (core layer), the surface crosslinked polymer layer is present as an intermediate layer on the outside of the elastic body, and the graft portion layer is the outermost layer (shell layer) outside the surface crosslinked polymer. The present embodiment is also an embodiment of the present invention.

(Volume average particle diameter (Mv) of polymer fine particles)
The volume average particle diameter (Mv) of the polymer fine particles is preferably 0.03 μm to 50.00 μm, and 0.05 μm to 10 μm, since it is possible to obtain a highly stable resin composition having a desired viscosity. .00 μm is more preferable, 0.08 μm to 2.00 μm is more preferable, 0.10 μm to 1.00 μm is even more preferable, 0.10 μm to 0.80 μm is even more preferable, and 0.10 μm to 0.50 μm is particularly preferable. . When the volume average particle diameter (Mv) of the polymer fine particles is within the above range, there is also an advantage that the dispersibility of the polymer fine particles in the matrix resin becomes good. In addition, in this specification, the "volume average particle diameter (Mv) of polymer microparticles" is intended to mean the volume average particle diameter of primary particles of polymer microparticles, unless otherwise specified. The volume average particle diameter of the polymer fine particles can be measured using a dynamic light scattering particle size distribution measuring device or the like using an aqueous latex containing the polymer fine particles as a sample.

(Glass transition temperature of polymer fine particles)
The glass transition temperature (Tg) of the polymer fine particles can be determined by the composition of the structural units contained in the polymer fine particles (for example, the composition of the structural units contained in each of the elastic body and the graft portion). In other words, changing the composition of the monomer used when producing (polymerizing) the polymer fine particles (for example, the composition of the monomer used when producing (polymerizing) each of the elastic body and the graft part) By doing so, the Tg of the obtained polymer fine particles can be adjusted.

The glass transition temperature (Tg) of the polymer microparticles can be calculated using the above-mentioned FOX formula (Equation 1), except that "graft portion of the polymer microparticles" is replaced with "polymer microparticles".

(2-3. Manufacturing method of polymer fine particles)
Hereinafter, an example of a method for producing polymer fine particles will be described, taking as an example a case where the polymer fine particles include a rubber-containing graft copolymer having an elastic body and a graft portion grafted to the elastic body. Explain. The polymer fine particles can be produced, for example, by polymerizing an elastic body and then graft-polymerizing a polymer constituting the graft portion to the elastic body in the presence of the elastic body.

Polymer fine particles can be produced by known methods such as emulsion polymerization, suspension polymerization, and microsuspension polymerization. Specifically, the polymerization of the elastic body, the polymerization of the graft portion (graft polymerization), and the polymerization of the surface crosslinked polymer in the polymer fine particles are carried out using known methods such as emulsion polymerization, suspension polymerization, and microsuspension polymerization. This can be done by any legal method. Among these, emulsion polymerization is particularly preferred as a method for producing polymer fine particles. In this specification, a latex obtained by such an emulsion polymerization method may be referred to as an "emulsion polymerization latex." According to the emulsion polymerization method, (i) compositional design of polymer fine particles is easy, (ii) industrial production of polymer fine particles is easy, and (iii) suitable for use in the present method for producing aggregates. It has the advantage of being easy to obtain latex. For these reasons, the latex used in the present method for producing an aggregate is preferably an emulsion polymerization latex. Hereinafter, a method for producing an elastic body, a graft portion, and a surface-crosslinked polymer having an arbitrary structure that can be included in the polymer fine particles will be explained.

(Method for manufacturing elastic body)
Consider a case where the elastic body contains at least one selected from the group consisting of diene rubber and (meth)acrylate rubber. In this case, the elastic body can be manufactured, for example, by a method such as emulsion polymerization, suspension polymerization, or microsuspension polymerization, and the method described in WO2005/028546 can be used as the manufacturing method. .

Consider a case where the elastic body contains organosiloxane rubber. In this case, the elastic body can be manufactured by a method such as emulsion polymerization, suspension polymerization, or microsuspension polymerization, and the method described in WO2006/070664 can be used as the manufacturing method. .

A case will be described in which the "elastic body" of the polymer fine particles is composed of a plurality of types of elastic bodies (for example, elastic body ₁ , elastic body ₂ , . . . , elastic body _n ). In this case, elastic body ₁ , elastic _{body 2} , . may be manufactured. Alternatively, elastic body ₁ , elastic _{body 2} , .

Multistage polymerization of an elastic body will be specifically explained. For example, a multi-stage polymerized elastic body can be obtained by sequentially performing the steps (1) to (4) below: (1) Polymerizing elastic body ₁ to obtain elastic body 1; (2) Next, elastic body ₁ is obtained by polymerizing elastic body 1; (3) Then, in the presence of elastic body _{1 +2, elastic} body ₃ is polymerized to obtain three-stage elastic body 1 _{+ 2+3} ; 4) After carrying out the same procedure, elastic body _n is polymerized in the presence of elastic bodies _{1+2+...+(n-1)} to obtain multi-stage polymerized elastic bodies _1+2+...+n .

(Method for manufacturing the graft part)
The graft part can be formed, for example, by polymerizing the monomer used for forming the graft part by known radical polymerization in the presence of an arbitrary polymer (for example, an elastic material). When (i) an elastic body or (ii) a polymer fine particle precursor containing an elastic body and a surface-crosslinked polymer is obtained as an aqueous latex, polymerization of the graft portion is preferably carried out by an emulsion polymerization method. The graft portion can be manufactured, for example, according to the method described in WO2005/028546.

A method for manufacturing a graft section will be described when the graft section is composed of a plurality of types of graft sections (for example, graft section ₁ , graft section ₂ , . . . , graft section _n ). In this case, graft part ₁ , graft part ₂ , ..., graft part _n are each polymerized separately by the above-mentioned method, and then mixed and composited to form a graft part consisting of multiple types of graft parts. (composite) may be produced. Alternatively, graft part ₁ , graft _{part 2} , .

The multistage polymerization of the graft portion will be specifically explained. For example, a multi-stage polymerized graft section can be obtained by sequentially performing the steps (1) to (4) below: (1) Graft section ₁ is polymerized to obtain graft section 1; (2) Graft section ₁ is then obtained by polymerizing graft section 1; Graft part ₂ is polymerized in the presence of part ₁ to obtain a two-stage graft part ₁₊₂ ; (3) Graft part ₃ is then polymerized in the presence of graft part ₁₊₂ to obtain a three-stage graft part ₁₊₂₊₃ ; 4) After carrying out the same procedure, graft part _n is polymerized in the presence of graft part _{1+2+...+(n-1)} to obtain multistage polymerized graft part _1+2+...+n .

When the graft portion is composed of multiple types of graft portions, the graft portion having the multiple types of graft portions may be polymerized, and then the graft portions may be graft-polymerized onto an elastic body to produce polymer fine particles. Polymer fine particles may be produced by successively performing multi-stage graft polymerization of a plurality of types of polymers constituting the graft portion onto the elastic body in the presence of the elastic body.

(Method for producing surface crosslinked polymer)
The surface crosslinked polymer can be formed by polymerizing the monomer used for forming the surface crosslinked polymer by known radical polymerization in the presence of an arbitrary polymer (for example, an elastomer). When the elastomer is obtained as an aqueous latex, the surface crosslinked polymer is preferably polymerized by emulsion polymerization.

When employing an emulsion polymerization method as a method for producing fine polymer particles, a known emulsifier (dispersant) can be used as an emulsifier (dispersant) for producing fine polymer particles.

Examples of the emulsifier include anionic emulsifiers, nonionic emulsifiers, polyvinyl alcohol, alkyl-substituted cellulose, polyvinylpyrrolidone, and polyacrylic acid derivatives. Examples of the anionic emulsifier include sulfur-based emulsifiers, phosphorus-based emulsifiers, sarcosic acid-based emulsifiers, and carboxylic acid-based emulsifiers. Examples of the sulfur-based emulsifier include sodium dodecylbenzenesulfonate (abbreviation: SDBS). Examples of the phosphorus emulsifier include polyoxyethylene lauryl ether sodium phosphate.

When using a polyfunctional monomer in the polymerization of an elastomer, graft portion, or surface crosslinked polymer for the purpose of introducing a crosslinked structure into the elastomer, graft portion, or surface crosslinked polymer, known chain transfer agents may be used. It can be used within the range of usage amount. By using a chain transfer agent, the molecular weight and/or degree of crosslinking of the resulting elastic body, graft portion, or surface crosslinked polymer can be easily adjusted.

In addition to the above-mentioned components, a surfactant can be used in the production of polymer fine particles. The type and amount of the surfactant used are within known ranges.

In the production of polymer fine particles, conditions such as polymerization temperature, pressure, and deoxidation during polymerization can be appropriately set within known numerical ranges.

Latex containing polymer particles can be obtained by the method for producing polymer particles described above. That is, the description in the section (2-3. Method for producing fine polymer particles) can be cited as a description regarding the method for producing latex.

(2-4. Thickener)
The latex may further include a thickener. When the latex contains a thickener, the latex tends to form a soft agglomerated state. By forming the latex in a soft agglomerated state, the bulk specific gravity of the powder and granules produced from the aggregates obtained by the present method for producing aggregates is increased, and the amount of fine powder during the production of the powder and granules is reduced. This has the advantage that the reduction effect is further enhanced. In this specification, the "soft agglomerated state" of latex means that the viscosity of the latex is lower than that before the addition of the thickener due to cross-linking between particles of polymer particles contained in the latex by the thickener. It refers to a state that is higher than.

As the thickener, known thickeners can be used. Thickeners suitably used in the present method for producing aggregates include water-soluble polymers. Examples of water-soluble polymers include nonionic water-soluble polymers, anionic water-soluble polymers, cationic water-soluble polymers, and amphoteric water-soluble polymers. Among these, nonionic water-soluble polymers are more preferred.

Examples of nonionic water-soluble polymers include polyalkylene oxide (for example, polyethylene oxide, polypropylene oxide, etc.), polyvinyl alcohol, methylcellulose, hydroxyethylmethylcellulose, hydroxyethylcellulose, hydroxypropylmethylcellulose, sodium polyacrylate, polyvinylpyrrolidone, polyacrylamide, Examples include polydimethylaminoethyl methacrylate. Among these, polyethylene oxide and methylcellulose are particularly preferred.

Polyethylene oxide includes polymers having ethylene oxide units obtained by polymerizing ethylene oxide. Examples of polyethylene oxide include ethylene oxide homopolymers, higher alcohol ethylene oxide adducts, alkylphenol ethylene oxide adducts, fatty acid ethylene oxide adducts, polyhydric alcohol fatty acid ester ethylene oxide adducts, higher alkylamine ethylene oxide adducts, fatty acid amide ethylene oxide adducts, oils and fats. Examples include ethylene oxide adducts, polypropylene glycol ethylene oxide adducts, and the like.

The molecular weight of the thickener (for example, polyethylene oxide) is not particularly limited, but the viscosity average molecular weight is preferably from 600,000 to 8,000,000, more preferably from 1,500,000 to 5,000,000. This configuration has the advantage that a soft agglomerated state of the latex is easily formed, and a rapid increase in the viscosity of the latex due to the addition of a thickener can be prevented. The viscosity average molecular weight M of polyethylene oxide can be calculated from the intrinsic viscosity η of polyethylene oxide using the following formula (Equation 2) (see J. Appl. Polymer Sci., 1, 56 (1959)).
η=6.4×10 ⁻⁶ ×M ^0.82 (Staudinger formula) (Formula 2).
Note that the intrinsic viscosity η of polyethylene oxide is a value obtained by measuring in pure water at a measurement temperature of 35° C. using a capillary viscometer.

Thickeners can be added to the latex in aqueous solution or in solid (eg powder) form. Since the operation is simple, it is more preferable to add the thickener to the latex in the form of an aqueous solution. There is no particular restriction on the method of adding the thickener to the latex, and a predetermined amount of the thickener may be (a) added to the latex all at once, or (b) added in several portions. or (c) continuously.

A case where a thickener is added to latex in the form of an aqueous solution will be explained. The concentration of the thickener in the thickener aqueous solution is not particularly limited, but it is such that (a) the aqueous solution has a viscosity suitable for handling, and (b) the water content of the latex is prevented from becoming too high. From this point of view, it is preferably 0.01% to 10.00% (weight/weight), and more preferably 0.10% to 10.00% (weight/weight).

The content of the thickener in the latex (based on solid content) is preferably 0.010 to 3.000 parts by weight (100 ppm to 30,000 ppm), based on 100 parts by weight of the polymer particles in the latex. More preferably, the amount is 0.015 to 0.050 parts by weight (150 to 500 ppm). This configuration has the following advantages: (a) the viscosity of the latex increases within an appropriate range; (b) the soft agglomerated state is quickly formed; and (c) the latex containing fine polymer particles and the coagulant are The advantage is that the contact time in the device (in other words, the time of the coagulation process) can be shortened, so the production cost can be lowered, and (d) the effect of reducing the amount of fine powder during the production of powder and granules. It has the advantage of further increasing

(2-5. Coagulant solution)
The coagulant solution used in the present method for producing an aggregate is intended to be a liquid coagulant and a solution containing a solvent and a coagulant. In this specification, the coagulant solution used in one embodiment of the present invention may be referred to as "the present coagulant solution." In this coagulant solution, the coagulant may be dispersed or dissolved in the solvent.

As used herein, the term "liquid coagulant" refers to a liquid substance that functions as a coagulant (that is, a substance in which the solute itself is liquid without being dissolved or dispersed in a solvent). When a liquid substance is used as a coagulant, the substance (coagulant) can be used as it is as a coagulant solution without dissolving or dispersing it in a solvent. That is, the "coagulant solution" in the present method for producing an aggregate includes the liquid substance itself that functions as a coagulant.

When a solution containing a solvent and a coagulant is used as the present coagulant solution, the solvent for the present coagulant solution is not particularly limited, but includes, for example, water.

The coagulant contained in the present coagulant solution may be any substance as long as it has the property of coagulating and coagulating the polymer particles in the latex. Examples of coagulants include (i) inorganic acids (salts) and/or organic acids (salts), and (ii) polymer coagulants. One type of these coagulants may be used alone, or two or more types may be used in combination. In addition, in this specification, an inorganic acid (salt) means "an inorganic acid and its salt", and an organic acid (salt) means "an organic acid and its salt."

This coagulant solution contains monovalent inorganic acids, salts of monovalent inorganic acids, divalent inorganic acids, salts of divalent inorganic acids, trivalent inorganic acids, and trivalent inorganic acids. Preferably, the solution is an aqueous solution containing one or more substances selected from the group consisting of salts and the like. Examples of monovalent inorganic acids include (a) halogen acids such as chloric acid, bromic acid, and iodic acid, and (b) nitric acid. Examples of divalent inorganic acids include sulfuric acid. Examples of trivalent inorganic acids include phosphoric acid. Examples of cationic elements or molecules that can form salts with these inorganic acids include alkali metals, alkaline earth metals, transition metals (particularly iron and zinc), Group 13 metals such as aluminum, and ammonium.

The present coagulant solution contains, as a coagulant, one or more substances selected from the group consisting of monovalent organic acids, monovalent organic acid salts, divalent organic acids, divalent organic acid salts, etc. It is preferable. Examples of monovalent organic acids include formic acid and acetic acid. Examples of monovalent organic acid salts include salts of formic acid, acetic acid, etc., and alkali metals. Examples of divalent organic acids include oxalic acid, malic acid, maleic acid, malonic acid, and tartaric acid. Examples of divalent organic acid salts include salts of acetic acid, formic acid, etc., and alkaline earth metals.

(i) Specific examples of inorganic acids (salts) and/or organic acids (salts) include:
(a) Alkali metal halides such as sodium chloride, potassium chloride, lithium chloride, sodium bromide, potassium bromide, lithium bromide, potassium iodide, and sodium iodide; alkali metal sulfides such as potassium sulfate and sodium sulfate; Ammonium sulfate; ammonium chloride; alkali metal nitrides such as sodium nitrate and potassium nitrate; calcium chloride, ferrous sulfate, magnesium sulfate, zinc sulfate, copper sulfate, barium chloride, ferrous chloride, ferric chloride, magnesium chloride, sulfuric acid Inorganic salts such as ferric iron, aluminum sulfate, potassium alum, iron alum;
(b) Inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid;
(c) Organic acids such as acetic acid and formic acid; and (d) Organic acid salts such as sodium acetate, calcium acetate, sodium formate, and calcium formate; and these organic acid salts.

The polymer coagulant is not particularly limited as long as it is a polymer compound having a hydrophilic group and a hydrophobic group. Examples of the polymer coagulant include anionic polymer coagulants, cationic polymer coagulants, nonionic polymer coagulants, and the like. Among these, cationic polymer coagulants are preferred because they have the advantage of neutralizing the charge on polymer fine particles.

Examples of the cationic polymer coagulant include polymer coagulants having a cationic group in the molecule, that is, polymer coagulants that exhibit cationic properties when dissolved in water. Specific examples of cationic polymer coagulants include polyamines, polydicyandiamides, cationized starch, cationic poly(meth)acrylamide, water-soluble aniline resin, polythiourea, polyethyleneimine, quaternary ammonium salts, and polyvinylpyridine. and chitosan.

Among the coagulants mentioned above, (a) sodium chloride, potassium chloride, sodium sulfate, ammonium chloride, calcium chloride, magnesium chloride, magnesium sulfate, An aqueous solution of a monovalent or divalent inorganic acid salt such as barium chloride, or (b) an aqueous solution of a monovalent or divalent inorganic acid such as hydrochloric acid or sulfuric acid, etc. can be suitably used.

The present coagulant solution can be obtained, for example, by mixing a solid (eg, powder) substance that functions as a coagulant with a solvent. When mixing multiple types of coagulants, each coagulant may be (a) mixed with a solvent all at once, or (b) each coagulant may be mixed individually. Moreover, a coagulant that is commercially available in a state in which it has been previously dissolved or dispersed in a solvent may be (a) used as it is as a coagulant solution, or (b) may be used after being further mixed with a solvent.

Furthermore, in the present method for producing an aggregate, a liquid substance that functions as a coagulant (i.e., a substance in which the solute itself is liquid without being dissolved or dispersed in a solvent) may be used as the coagulant. When using a liquid substance as a coagulant, it may be used after dissolving or dispersing the substance (coagulant) in a solvent to form a solution; dissolving or dispersing the substance (coagulant) in a solvent Alternatively, the substance (coagulant) may be sprayed and used as is.

The concentration of the coagulant in the coagulant solution is not particularly limited, but for example, it is preferably 0.1% to 45.0% by weight, and 5.0% by weight based on the total amount of 100% by weight of the coagulant solution. The content is more preferably from 10.0% to 35.0% by weight, and even more preferably from 10.0% to 35.0% by weight. According to this configuration, the coagulating action of the coagulant can be easily exerted, and the amount of coagulant used can be reduced. As a result, it has the advantage of (a) being able to reduce the manufacturing cost of aggregates and powder and granules, and (b) being able to reduce the amount of contaminants derived from the coagulant contained in the aggregates and powder.

When the coagulant is a solid (e.g. powder) substance, the concentration of the coagulant in the coagulant solution can be calculated, for example, by the following method: 0.5 g of the coagulant solution is heated at a temperature higher than the boiling point of the solvent ( For example, the solvent is evaporated by placing it in a hot air convection dryer at a temperature of 20° C. above the boiling point of the solvent for 3 hours. Next, the weight (g) of the residue (solid content) after drying is measured. Next, the obtained value is divided by the weight of the coagulant solution before drying, 0.5 g, and the obtained value is further multiplied by 100. The residue after drying, ie the solid content, mainly contains coagulant. Therefore, the "concentration of the coagulant in the coagulant solution" calculated by the above-mentioned method can also be rephrased as "the concentration of solid content in the coagulant solution." Furthermore, when the coagulant is in a liquid state, the concentration of the coagulant in the coagulant solution can also be measured by performing fractional distillation.

(2-6. Equipment)
The apparatus used in the method for producing the present aggregate (hereinafter sometimes referred to as the production apparatus or device) includes sprayed and/or dropped latex droplets of polymer fine particles, and a sprayed coagulant solution. A container (sometimes referred to as a "coagulation tank") in which a gas phase region that can come into contact with droplets of the latex, and a nozzle (a first nozzle ), and a nozzle (second nozzle) that communicates with the inside of the device as a coagulant solution introduction part.

As the device, for example, a device including a container having a vertical or substantially vertical inner wall can be used. The device may be, for example, (i) a first device that includes a first nozzle at the top of the container (tower top) and a second nozzle at the side surface (inner wall) of the container; or (ii) it may be a second device that includes a first nozzle on the side surface (inner wall) of the container and a second nozzle on the top (tower top) of the container. In the second device, the horizontal distance between the first nozzle and the second nozzle is preferably longer than the vertical distance between the first nozzle and the second nozzle. The first device is, for example, a container used in the first contacting step. The second device is, for example, a container used in the second contact step. Further, the container may have a receiving tank on the bottom portion, which includes an aqueous phase region for collecting aggregates generated in the gas phase region of the container.

The shape of the container is not particularly limited, but a cylindrical shape, a polygonal prism shape, etc. are preferable, and a cylindrical shape is more preferable. When the container has a cylindrical shape, its diameter is preferably 30 cm to 500 cm, for example. In addition, the height from the top of the column to the bottom of the container (if it has a receiver tank, the liquid level (aqueous phase surface) of the receiver tank) should be set appropriately to prevent agglomeration of polymer fine particles in the latex in the gas phase. From the viewpoint of progress, the distance is preferably 50 cm to 10 m, more preferably 1 m to 5 m, and even more preferably 2 m to 3 m.

In the apparatus used in the first contact step, the first nozzle is a nozzle capable of vertically spraying and/or dropping latex, and the second nozzle is capable of horizontally spraying a coagulant solution. It's a nozzle. Moreover, in the apparatus used for the second contact step, the first nozzle is a nozzle that can spray the latex horizontally, and the second nozzle is a nozzle that can spray and/or drop the coagulant solution vertically. This is a possible nozzle.

The device also includes a recovery device for recovering the obtained aggregates from the device, a drying device for drying the recovered aggregates to obtain powder, and a temperature control system for adjusting the temperature inside the container and controlling the temperature of the polymer fine particles. A temperature control device for controlling the temperature of the latex and/or the temperature of the coagulant solution may be connected as necessary.

(2-7. First contact step and second contact step)
In one embodiment of the present invention, the method for producing an aggregate includes spraying and/or dropping a latex of polymer particles vertically from a first nozzle, and spraying a coagulant solution horizontally from a second nozzle. and a first contacting step of contacting the latex droplet and the coagulant solution droplet. In one embodiment of the present invention, the method for producing an aggregate includes spraying and/or dropping a coagulant solution vertically from a second nozzle, and spraying latex horizontally from a first nozzle to form a latex. a second contacting step of contacting the droplets of the coagulant solution with the droplets of the coagulant solution, and in the second contacting step, the horizontal distance between the first nozzle and the second nozzle is It is longer than the vertical distance between the first nozzle and the second nozzle.

In both the first contact step and the second contact step, the latex and coagulant present in the gas phase are removed by contacting the latex droplets with the coagulant solution droplets in the gas phase. Agglomerates of polymer microparticles can be generated in droplets containing a solution. In addition, the droplets containing the latex and the coagulant solution obtained in the first contact step and the second contact step can be said to be "droplets formed by integrating the latex and the coagulant solution", It can also be said that "droplets of a solution containing polymer fine particles derived from the polymer particles and a coagulant derived from the coagulant solution."

In the first contact step and the second contact step, the order of spraying and/or dropping the latex of the polymer fine particles and spraying the coagulant solution is not particularly limited, and they may be performed simultaneously. The spraying may be performed before the spraying and/or dropping of the latex of the polymer fine particles. For example, a coagulant solution is sprayed in advance, and a latex of polymer fine particles is sprayed and/or dropped into an area containing the coagulant solution in the form of atomized gas, and the latex droplets and the coagulant solution droplets are combined. may be brought into contact.

The first nozzle is not particularly limited as long as it can spray and/or drip latex, but a pressure nozzle, two-fluid nozzle, ultrasonic nozzle, high-frequency device, dripping nozzle, etc. can be selected and used as appropriate. can. Among these, it is possible to easily spray droplets having a volume average droplet diameter of 200 μm to 400 μm and a sharp particle size distribution, and it is economically superior among nozzles that can spray such droplets. The first nozzle is more preferably a pressure nozzle, and even more preferably a swirling nozzle. When the latex is sprayed and/or dropped from the first nozzle, the latex droplets and the coagulant solution droplets can be integrated in the gas phase, and the droplets containing the latex and the coagulant solution can be combined. The polymer fine particles can be agglomerated.

The diameter of the first nozzle is, for example, 0.01 mm to 2.00 mm, preferably 0.05 mm to 1.50 mm, and more preferably 0.10 mm to 1.00 mm. When the diameter is 2.00 mm or less, there is no risk that the sprayed and/or dropped latex droplets will become excessively large, and the polymer fine particles can be sufficiently aggregated in the droplets containing the latex and coagulant solution. I can do it. Therefore, it has the advantage that it is possible to obtain aggregates that can provide powder or granules with high bulk specific gravity. On the other hand, if the diameter of the first nozzle is 0.01 mm or more, the possibility that the hole of the first nozzle is clogged during spraying and/or dropping of latex can be reduced, and aggregates can be stably produced. be able to.

The spray pressure of the first nozzle is, for example, 0.5 kg/cm ² to 30.0 kg/cm ² , preferably 1.0 kg/cm ² to 10.0 kg/cm ² . If the spray pressure of the first nozzle is 0.5 kg/cm2 ^or more, there is no risk that the sprayed latex droplets will become excessively large, and as a result, the aggregation reaction of the polymer fine particles in the gas phase can be carried out appropriately. It has the advantage of being completed. In addition, if the spray pressure of the first nozzle is 30.0 kg/cm ² or less, there is no risk that the sprayed latex droplets will become excessively small, and as a result, the powder or granules produced from the resulting aggregates This has the advantage that the amount of fine powder is reduced.

The tip angle of the latex spray cone sprayed or dripped from the first nozzle is not particularly limited, but is preferably from 5° to 140°, and preferably from 30° to 90°. When the angle of the latex spray cone is within the above range, (i) it is possible to efficiently produce aggregates, and (ii) it is possible to suppress excessive enlargement of the equipment used for producing the aggregates. can. Furthermore, (iii) by setting the tip angle of the spray cone to 5° or more, it is possible to prevent the sprayed or dropped latex droplets from coalescing with each other and increasing the droplet diameter, and (iv) By setting the tip angle of the spray cone to 90° or less, the amount of sprayed or dropped latex droplets adhering to the wall surface of the apparatus for producing aggregates can be reduced, and the amount of latex droplets can be reduced. Since there is no need to increase the size of the device in order to prevent adhesion to the wall surface, the device can also be made smaller. Note that in this specification, the term "spray cone" refers to an aggregate of droplets of the liquid sprayed or dropped from the outlet of a nozzle, which is observed when a liquid is sprayed or dropped. Further, the shape of the latex spray cone is not particularly limited, and may be, for example, fan-shaped, empty conical, full conical, or flat.

The number of first nozzles is not particularly limited, and may be one or two or more. Furthermore, when two or more nozzles are used as the first nozzle, (a) only the latex may be sprayed from each nozzle, (b) only the latex may be dripped from each nozzle, and ( c) Latex may be sprayed from at least one nozzle while dropping latex from at least one other nozzle.

The second nozzle is not particularly limited as long as it can spray and/or drop the coagulant solution, but a pressure nozzle, two-fluid nozzle, ultrasonic nozzle, high-frequency device, or dripping nozzle may be appropriately selected and used. be able to. Among these, the second nozzle is preferred because it can easily spray droplets having a volume average droplet diameter of 1 μm to 100 μm, and because it is economically superior among nozzles that can spray such droplets. , two-fluid nozzles are more preferred. When the coagulant solution is sprayed and/or dripped from the second nozzle, the latex droplets and the coagulant solution droplets can be integrated in the gas phase, and a liquid containing the latex and the coagulant solution is formed. Polymer microparticles can be aggregated in the drop.

The diameter of the second nozzle is, for example, 0.01 mm to 2.00 mm, more preferably 0.05 mm to 1.50 mm, and still more preferably 0.10 mm to 1.00 mm. When the diameter is 2.00 mm or less, there is no risk that the droplets of the sprayed coagulant solution will become excessively large, and the polymer particles can be sufficiently aggregated in the droplets containing the latex and the coagulant solution. . Therefore, it has the advantage that it is possible to obtain aggregates that can provide powder or granules with high bulk specific gravity. Moreover, if the diameter of the second nozzle is 0.01 mm or more, the possibility that the nozzle will become clogged during spraying of the coagulant solution can be reduced, and aggregates can be stably produced.

The spray pressure of the second nozzle is, for example, 0.5 kg/cm ² to 100.0 kg/cm ² , more preferably 1.0 kg/cm ² to 5.0 kg/cm ² . If the spray pressure of the second nozzle is 0.5 kg/cm2 ^or more, there is no risk that the droplets of the sprayed coagulant solution will become excessively large, and the droplet density of the coagulant solution in the gas phase will increase. Therefore, there is an advantage that the coagulant capture efficiency is increased, or in other words, the latex droplets and the coagulant droplets can be brought into contact with each other efficiently. In addition, if the spray pressure of the second nozzle is 100.0 kg/ ^cm2 or less, there is no risk that the droplet scattering range will become too wide and the droplet density in the gas phase will become small. It has the advantage that it can be brought into efficient contact with the coagulant solution.

The tip angle of the spray cone of the coagulant solution sprayed from the second nozzle is not particularly limited, but is preferably from 5° to 140°, and preferably from 30° to 90°. When the angle of the spray cone of the coagulant solution is within the above range, (i) the latex droplets and the additive solution droplets can be brought into contact efficiently, and (ii) they can be used to produce aggregates. Excessive enlargement of the device can be suppressed. Furthermore, (iii) in particular, by setting the tip angle of the spray cone to 5° or more, it is possible to prevent the droplets of the sprayed coagulant solution from coalescing with each other and increasing the droplet diameter; (iv) By setting the tip angle of the spray cone to 90° or less, the amount of sprayed coagulant solution droplets adhering to the wall surface of the apparatus for producing aggregates can be reduced, and the Since there is no need to increase the size of the device in order to prevent droplets from adhering to the wall surface, the device can be made smaller; There is also the advantage that the latex droplets and coagulant solution can be brought into contact efficiently since there is no risk of the droplet density in the phase becoming small. Further, the shape of the spray cone for the coagulant solution is not particularly limited, and may be, for example, fan-shaped, empty conical, full conical, or flat. .

The number of second nozzles is not particularly limited, and may be one or two or more. In addition, when two or more nozzles are used as the second nozzle, (a) only the coagulant solution may be sprayed from each nozzle, or (b) only the coagulant solution may be dripped from each nozzle. (c) While spraying the coagulant solution from at least one nozzle, the coagulant solution may be dropped from at least one other nozzle.

In the first contact step, the first nozzle is preferably installed at the top of the container (tower top). In addition, in the first contact step, sufficient coagulation time can be secured and powder with better powder quality can be provided. The distance in the vertical direction from the liquid level (aqueous phase surface) of the receiving tank is preferably 100 cm or more, more preferably 150 cm or more, and even more preferably 200 cm or more. The upper limit of the vertical distance between the first nozzle and the bottom surface of the container is preferably 300 cm or less from the viewpoint of suppressing excessive enlargement of the device.

In this specification, "the vertical distance between the first nozzle and the bottom surface of the container (if the manufacturing device has the receiving tank, the liquid level (aqueous phase surface) of the receiving tank)" is the first nozzle. The distance in the vertical direction is intended to be the distance between the center of the nozzle outlet and the bottom of the container (if the manufacturing device has the receiving tank, the liquid level (aqueous phase surface) of the receiving tank). In addition, when there are multiple first nozzles, the shortest (closest) value among the vertical distances between each first nozzle and the bottom of the container is calculated as the distance between the first nozzle and the bottom of the container. The vertical distance between

In the first contacting step, the position of the second nozzle may be such that the coagulant solution can be horizontally sprayed to bring the latex droplets and the coagulant solution droplets into contact. However, it is not particularly limited. In the first contact step, the second nozzle is preferably provided on the side surface (inner wall) of the container so that the spray direction is horizontal so that the coagulant solution can be sprayed horizontally. Further, in the first contact step, the second nozzle is preferably provided below the first nozzle so that the latex droplets and the coagulant solution droplets can be brought into contact with each other.

In the first contact step, the horizontal distance between the first nozzle and the second nozzle is preferably 20 cm to 45 cm, more preferably 20 cm to 40 cm, even more preferably 20 cm to 35 cm. , 20 cm to 30 cm is particularly preferred. When the horizontal distance between the first nozzle and the second nozzle is 20 cm or more, the coagulant adheres to the outlet of the first nozzle and the outlet of the first nozzle is blocked. Since there is no risk that the latex cannot be sprayed from the nozzle, it has the advantage that aggregates can be produced continuously and stably. When the horizontal distance between the first nozzle and the second nozzle is within 45 cm, the speed of the coagulant solution droplets sprayed from the second nozzle does not become too slow, so that the latex droplets and the coagulant solution This has the advantage that the relative velocity difference between the latex droplet and the coagulant solution droplet becomes large, and as a result, the contact efficiency between the latex droplet and the coagulant solution droplet becomes good.

In the first contact step, the vertical distance between the first nozzle and the second nozzle is preferably 20 cm to 55 cm, more preferably 20 cm to 50 cm, even more preferably 20 cm to 45 cm. , 20 cm to 40 cm is particularly preferred. When the vertical distance between the first nozzle and the second nozzle is 20 cm or more, the coagulant adheres to the outlet of the first nozzle and the outlet of the first nozzle is blocked. Since there is no risk that the latex cannot be sprayed from the nozzle, it has the advantage that aggregates can be produced continuously and stably. When the vertical distance between the first nozzle and the second nozzle is within 55 cm, the speed of the coagulant solution droplets sprayed from the second nozzle does not become too slow, so the latex droplets and the coagulant solution This has the advantage that the relative velocity difference between the latex droplet and the coagulant solution droplet becomes large, and as a result, the contact efficiency between the latex droplet and the coagulant solution droplet becomes good.

In the first contact step, the horizontal distance between the first nozzle and the second nozzle is preferably longer than the vertical distance between the first nozzle and the second nozzle. According to this configuration, there is an advantage that the fine powder ratio can be further reduced and a powder or granular material having a larger circularity and bulk specific gravity can be obtained.

In the second contact step, the position of the first nozzle is particularly limited as long as it is a position where the latex can be sprayed horizontally and the droplets of the latex and the droplets of the coagulant solution can come into contact with each other. It is not something that will be done. In the second contact step, the first nozzle is preferably provided on the side surface (inner wall) of the container so that the spray direction is horizontal so that the latex can be sprayed horizontally. Further, in the second contact step, the first nozzle is preferably provided below the second nozzle so that the latex droplets and the coagulant solution droplets can be brought into contact with each other.

In the second contact step, the second nozzle is preferably installed at the top of the container (tower top). In addition, in the second contact step, sufficient coagulation time can be secured and powder with better powder quality can be provided. In this case, the distance in the vertical direction from the liquid level (aqueous phase surface) of the receiving tank is preferably 100 cm or more, more preferably 150 cm or more, and even more preferably 200 cm or more. The upper limit of the vertical distance between the second nozzle and the bottom surface of the container is preferably 300 cm or less from the viewpoint of suppressing excessive enlargement of the device.

In this specification, "the vertical distance between the second nozzle and the bottom surface of the container (if the manufacturing device has the receiving tank, the liquid level (aqueous phase surface) of the receiving tank)" The distance in the vertical direction is intended to be the distance between the center of the nozzle outlet and the bottom of the container (if the manufacturing device has the receiving tank, the liquid level (aqueous phase surface) of the receiving tank). In addition, when there are multiple second nozzles, the shortest (closest) value among the vertical distances between each second nozzle and the bottom of the container is calculated as the distance between the second nozzle and the bottom of the container. The vertical distance between

In the second contact step, the horizontal distance between the first nozzle and the second nozzle is preferably 45 cm to 55 cm, more preferably 45 cm to 50 cm. When the horizontal distance between the first nozzle and the second nozzle is 45 cm or more, the coagulant adheres to the outlet of the first nozzle and the outlet of the first nozzle is blocked. Since there is no risk that the latex cannot be sprayed from the nozzle, it has the advantage that aggregates can be produced continuously and stably. When the horizontal distance between the first nozzle and the second nozzle is within 55 cm, the speed of the coagulant solution droplets sprayed from the second nozzle does not become too slow, so that the latex droplets and the coagulant solution This has the advantage that the relative velocity difference between the latex droplet and the coagulant solution droplet becomes large, and as a result, the contact efficiency between the latex droplet and the coagulant solution droplet becomes good.

In the second contact step, the vertical distance between the first nozzle and the second nozzle is preferably 20 cm to 45 cm, more preferably 20 cm to 40 cm, even more preferably 20 cm to 35 cm. , 20 cm to 30 cm is particularly preferred. When the vertical distance between the first nozzle and the second nozzle is 20 cm or more, the coagulant adheres to the outlet of the first nozzle and the outlet of the first nozzle is blocked. Since there is no risk that the latex cannot be sprayed from the nozzle, it has the advantage that aggregates can be produced continuously and stably. When the vertical distance between the first nozzle and the second nozzle is within 45 cm, the speed of the coagulant solution droplets sprayed from the second nozzle does not become too slow, so the latex droplets and the coagulant solution This has the advantage that the relative velocity difference between the latex droplet and the coagulant solution droplet becomes large, and as a result, the contact efficiency between the latex droplet and the coagulant solution droplet becomes good.

In the first contact step and the second contact step, the latex droplet and the coagulant solution are separated in a region where the relative velocity difference between the latex droplet and the coagulant solution is 2.2 m/s or more. Preferably, contact is made with a droplet of the solution. According to this configuration, there is an advantage that the fine powder ratio can be further reduced and a powder or granular material having a larger circularity and bulk specific gravity can be obtained. In order to enjoy more of these advantages, the relative speed difference is more preferably 2.3 m/s or more, more preferably 2.4 m/s or more, and more preferably 2.5 m/s or more. More preferably, it is 2.6 m/s or more, more preferably 2.7 m/s or more, more preferably 2.8 m/s or more, and 2.9 m/s or more. more preferably 3.0 m/s or more, more preferably 3.1 m/s or more, more preferably 3.2 m/s or more, 3.5 m/s or more More preferably, the speed is 4.0 m/s or more, more preferably 4.5 m/s or more, more preferably 5.0 m/s or more, 5.5 m/s or more. It is more preferable that it is s or more, and it is especially preferable that it is 6.0 m/s or more. The method for measuring the relative velocity difference between the latex droplet and the coagulant solution droplet will be explained in detail in Examples below.

The volume average droplet diameter of the latex droplets sprayed and/or dropped in the first contact step and the second contact step is preferably 50 μm to 5 mm, more preferably 100 μm to 800 μm, even more preferably 150 μm to 600 μm, particularly preferably 200 μm to 400 μm. If the volume average droplet diameter of the latex droplets sprayed and/or dropped is 50 μm or more, the amount of fine powder in the powder obtained by producing the resulting aggregate can be reduced. In addition, if the volume average droplet diameter of the latex droplets sprayed and/or dropped is 5 mm or less, the polymer fine particles in the latex droplets can be sufficiently aggregated, so that the resulting aggregates are , it is possible to provide powder and granular material with high bulk specific gravity and a small amount of fine powder.

The volume average droplet diameter of the droplets of the coagulant solution sprayed and/or dropped in the first contact step and the second contact step is preferably 0.01 μm to 500.00 μm, and preferably 0.05 μm to It is more preferably 100.00 μm, and even more preferably 0.10 μm to 50.00 μm. According to the above configuration, it is possible to obtain aggregates with a small amount of microaggregates, and the aggregates have the advantage of being able to provide powder and granular material with a small percentage of fine particles. Moreover, according to the above-mentioned structure, there is an advantage that it is possible to provide powder and granular material that is further excellent in bulk specific gravity and circularity.

The volume average droplet diameter of the latex and coagulant solution droplets can be measured, for example, by a laser diffraction spray droplet diameter measuring device.

In the first contact step and the second contact step, the amount of coagulant sprayed depends on the type (composition) of the polymer fine particles, the type of coagulant, the concentration of the polymer fine particles (solid content) in the latex, and the coagulation rate. It can be adjusted as appropriate depending on the concentration of the coagulant (solid content) in the agent solution. In this specification, the "amount of coagulant sprayed" can also be referred to as "the amount of coagulant brought into contact with latex droplets", and refers to the polymer particles (solid content) in the latex that is sprayed and/or dropped per unit time. It is intended to be the amount of coagulant (solid content) in the coagulant solution sprayed per unit time relative to the amount of . The "amount of coagulant sprayed" can also be said to be the "amount of coagulant brought into contact with latex droplets." (a) generation of unagglomerated portions of polymer fine particles in droplets containing latex and coagulant solution can be prevented, and more aggregates can be obtained; and (b) aggregates obtained and Since it has the advantage of reducing contaminants derived from the coagulant contained in the powder, the amount of coagulant sprayed is determined by the amount of polymer fine particles (polymer fine particles) in the latex sprayed and/or dropped per unit time. The amount is preferably 1 to 30 parts by weight, more preferably 2 to 20 parts by weight, and 3 to 15 parts by weight based on 100 parts by weight (total amount of sprayed and dropped amount of fine particles). Parts by weight are more preferred. The "amount of coagulant sprayed" can be adjusted by appropriately changing the concentration of the coagulant (solid content) in the coagulant solution, the amount of the coagulant solution sprayed per unit time, and the like.

The temperature of the latex (immediately before spraying and/or dropping) when subjected to the first contact step and the second contact step is not particularly limited. In one embodiment of the present invention, the temperature of the latex when subjected to the contacting step is, for example, preferably from 1°C to 100°C, more preferably from 1°C to less than 100°C, and from 5°C to The temperature is more preferably 80°C, even more preferably 10°C to 70°C, and particularly preferably 20°C to 50°C. When the temperature of the latex during the contacting step is within the above range, there is an advantage that the stability of the latex can be ensured.

The temperature of the coagulant solution (immediately before spraying) when subjected to the first contacting step and the second contacting step is not particularly limited. In one embodiment of the present invention, the temperature of the coagulant solution when subjected to the contacting step is, for example, preferably 1°C to 100°C, more preferably 1°C or more and less than 100°C, The temperature is preferably from 10°C to 80°C, even more preferably from 10°C to 70°C, and particularly preferably from 20°C to 50°C. When the temperature of the coagulant solution when subjected to the contacting step is within the above range, there is an advantage that there is no risk of the coagulant precipitating and the stability of the coagulant solution can be ensured.

Further, the temperature inside the container in the first contact step and the second contact step (temperature in the area where the latex droplets and the coagulant solution droplets come into contact) is not particularly limited, but is, for example, 1° C. to The temperature is preferably 100°C, more preferably 1°C or more and less than 100°C, more preferably 5°C to 80°C, more preferably 10°C to 70°C, and more preferably 15°C to 60°C. The temperature is more preferably 15°C to 50°C, even more preferably 15°C to 45°C, and particularly preferably 15°C or more and less than 45°C. When the temperature inside the container in the contacting step is within the above range, the latex droplets and the coagulant solution droplets can efficiently contact each other, so that the polymer particles can be formed in the liquid containing the latex and the coagulant solution. It has the advantage of being able to be sufficiently agglomerated.

In the present method for producing an aggregate, the first contacting step and the second contacting step may be carried out while water is flowing down along the inner wall surface of the container in which the contacting step is performed (flowing operation). According to this configuration, if there is a deposit on the inner wall surface, the deposit can be removed. The amount of water flowing down along the inner wall surface is not particularly limited. According to one embodiment of the present invention, the amount of water used can be reduced compared to conventional methods because the adhesion of the latex, coagulant solution, and resulting aggregates to the inner wall surface of the container is reduced. , and the burden of wastewater treatment can be reduced. The temperature of the water flowing down along the inner wall surface is preferably 0° C. to 100° C., more preferably 10° C. to 60° C., from the viewpoint of simplifying the flowing operation.

The fineness ratio of the powder or granule depends on the proportion of minute aggregates (microaggregates) contained in the aggregate that is the material used to obtain the powder or granule. Specifically, there is a positive correlation between the amount of microaggregates contained in an aggregate and the fineness ratio of the powder obtained from the aggregate. In other words, aggregates with a small amount of microaggregates can provide powder and granules with a small percentage of fine particles. The method for producing aggregates according to one embodiment of the present invention can provide aggregates with a small amount of microaggregates, and as a result, can provide powder particles with a small percentage of fine particles. Using a suspension of aggregates as a sample, measuring the particle size distribution of aggregates in the suspension using a laser diffraction/scattering particle size distribution measuring device LA-950 (manufactured by Horiba, Ltd.), Next, the particle size distribution is determined from the volume cumulative frequency % of aggregates with a volume average particle diameter of 1 μm or more and 3 mm or less. The proportion of aggregates with a particle diameter of 50 μm or less in 100% of aggregates, calculated based on the obtained results, is herein referred to as "amount of microaggregates (%) of aggregates". The amount (%) of microaggregates in the present aggregate is preferably 8.0% or less, more preferably 7.9% or less, more preferably 7.8% or less, 7. It is more preferably 7% or less, more preferably 7.6% or less, more preferably 7.5% or less, more preferably 7.3% or less, 7.0% It is more preferably at most 6.5%, more preferably at most 6.0%, more preferably at most 5.5%, and at most 5.0%. More preferably, it is 4.5% or less, more preferably 4.0% or less, more preferably 3.5% or less, and 3.0% or less. is more preferable, and particularly preferably 2.5% or less. When the amount (%) of microagglomerates in the aggregates is 8.0% or less, there is an advantage that it is possible to provide a powder or granular material with a fine powder ratio of 8.0% or less.

[3. Manufacturing method of powder and granular material]
A method for producing powder or granular material according to an embodiment of the present invention includes a recovery step of recovering aggregates obtained by the present method for producing aggregates, and a drying step of drying the recovered aggregates. . In this specification, a method for producing a powder or granule according to an embodiment of the present invention may be referred to as "this method for producing a powder or granule." It can also be said that the present method for producing powder or granules includes the present method for producing aggregates as one step.

Since the present method for producing a powder or granule has the above-mentioned structure, it has the advantage of being able to provide a powder or granule with a small percentage of fine powder. Further, since the present method for producing a granular material has the above-mentioned structure, it also has the advantage of being able to provide a granular material with a high degree of circularity (close to 1) and a large bulk specific gravity.

Each process related to the method for producing the present powder or granular material will be explained below, except for matters detailed below. The description in the section "Method for producing aggregates" is incorporated herein by reference.

(3-1. Recovery process)
The recovery step is a step of recovering the aggregate obtained by the present method for producing an aggregate. In the recovery step, the method for recovering the aggregates is not particularly limited, and various methods can be applied. For example, the aggregates that have descended in the gas phase of the container in which the contacting step has been carried out are lowered into a receiving tank that is installed at the bottom of the container and has an aqueous phase, and then the slurry containing the aggregates is taken out from the receiving tank, and the slurry is It can be recovered by separating the aggregates from.

Here, the method (separation method) for separating the aggregates from the slurry is not particularly limited, but for example, methods such as centrifugal dehydration, static separation, filtration dehydration, compression dehydration, or water evaporation are applied. can. Moreover, the equipment for carrying out the various separation methods described above can be appropriately selected according to the desired separation method. For example, screw presses, roller presses, belt screens, vibrating screens, multi-plate vibrating filters, vacuum dehydrators, pressure dehydrators, belt presses, centrifugal dehydrators, etc. can be used.

More preferably, the recovery step further includes a heat treatment step of heat-treating the slurry containing the aggregates before separating the aggregates from the slurry. The temperature for heat treatment of the slurry is not particularly limited, but is, for example, 60°C to 98°C, more preferably 60°C to 95°C. The time for heat treatment of the slurry is not particularly limited, but for example, it is preferably from 30 seconds to 30 minutes, more preferably from 1 minute to 20 minutes, and even more preferably from 1 minute to 10 minutes. By heat-treating the slurry containing the aggregates, the bulk density of the aggregates can be increased, and powder or granules with higher bulk density can be obtained. The heat treatment of the slurry may be performed on the slurry in the receiving tank, or may be performed after the slurry is taken out from the receiving tank. The method of heat treatment is also not particularly limited, and for example, a method of supplying high temperature (for example, 130° C.) steam to the slurry may be mentioned. When heat-treating the slurry in the receiving tank, the heat treatment can also be performed by adjusting the temperature of a solution containing a coagulant in the receiving tank, which will be described later, within the above range.

The aqueous phase in the receiving tank may be water, but is preferably a solution containing the coagulant, since insufficiently coagulated aggregates can be coagulated more reliably. When a solution containing a coagulant is used as the aqueous phase, the concentration of the coagulant in the solution is not particularly limited, but is preferably 0.01% to 15.00% by weight, and 0.05% by weight. % to 10% by weight, and even more preferably 0.10% to 5.00% by weight. Note that when the aqueous phase used in the recovery step is a solution containing a coagulant, the concentration of the coagulant in the solution may be the same as the concentration of the coagulant solution used in the contact step, but aggregates and The coagulation method has the advantages of reducing the production cost of powder and granules, reducing the amount of contaminants derived from coagulants that may be contained in aggregates and powders, and ensuring storage stability. The concentration is preferably lower than that of the agent solution.

When a solution containing a coagulant is used as the aqueous phase in the receiver tank, the coagulant solution in the contact step falls into the receiver tank and mixes with the aqueous phase (solution containing the coagulant). The concentration of the coagulant in the solution may change unintentionally. For example, if the concentration of coagulant in the aqueous phase (solution containing coagulant) is lower than the concentration of coagulant in the coagulant solution used in the contacting step, the concentration of coagulant in the aqueous phase (solution containing coagulant) rises. The concentration of the coagulant in the aqueous phase (solution containing the coagulant) in the recovery step is preferably controlled within a desired range. The control method is not particularly limited, but for example, when the contact step is carried out while performing a flowing operation, the water phase (a solution containing a coagulant) is coagulated by flowing the flowing water into a receiving tank. The concentration of the agent can be controlled within a desired range.

The temperature of the solution containing the coagulant in the receiving tank in the recovery process is not particularly limited, but from the viewpoint of not allowing aggregates to fuse together and coagulating insufficiently coagulated aggregates more fully, the temperature is 20°C. The temperature is preferably from 100°C to 40°C, more preferably from 40°C to 100°C, even more preferably from 60°C to 100°C.

(3-2. Drying process)
The drying process is a process of drying the aggregates collected in the recovery process, and by drying the aggregates, water derived from the latex, coagulant solution, and water phase in the receiving tank contained in the aggregates is removed. At the same time, it can also be said that this is a process of promoting fusion between polymer fine particles within the aggregate.

In the drying step, the method for drying the aggregate is not particularly limited, and any known method can be used. For example, the aggregates may be dried by subjecting them to heat treatment.

When drying the aggregate by heat treatment, the temperature of the heat treatment of the aggregate is not particularly limited, but for example, it is preferably 40°C to 120°C, more preferably 60°C to 120°C, and 60°C The temperature is more preferably from 100°C to 65°C to 95°C. Further, the time for heat treatment of the aggregate is, for example, preferably 1 minute to 90 minutes, more preferably 1 minute to 60 minutes, and even more preferably 5 minutes to 30 minutes.

In carrying out the heat treatment, it is preferable to suppress the aggregation of aggregates (agglomeration between powder particles) during heating and (after) drying. Therefore, it is preferable to add 0.5 to 3.0 parts by weight of the hard inelastic polymer latex (based on solid content) to 100 parts by weight of the aggregate (based on solid content) before heat treatment. The hard inelastic polymer latex may be added to the aggregates before the heat treatment. For example, the hard inelastic polymer latex may be added to the aggregates recovered in the recovery step and mixed before the heat treatment, or the It may be added to the aggregate in the recovery step by containing it in the aqueous phase. By heat-treating the aggregate to which the hard inelastic polymer latex has been added under the above-mentioned heat treatment conditions, it is possible to obtain a granular material in which aggregation between the granular materials is suppressed.

The hard inelastic polymer may have a small amount of a monomer capable of forming a rubber elastic body, such as butadiene (for example, 30% by weight or less, preferably 20% by weight or less, more preferably 10% by weight or less of the entire polymer). % or less, especially 0% by weight), a polymer obtained by polymerizing other monomers can be used. Examples of monomers that do not form rubber elastic bodies include (1) alkyl groups having 10 or less carbon atoms such as methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate; (2) Vinyl arenes such as styrene, α-methylstyrene, monochlorostyrene, dichlorostyrene, vinyl cyanates such as acrylonitrile, (3) 1,3-butylene glycol di(meth) Examples include polyfunctional monomers such as acrylate, allyl (meth)acrylate, diallyl phthalate, triallyl cyanurate, monoethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, divinylbenzene, and glycidyl (meth)acrylate. be done. These monomers can be used alone or in appropriate combinations.

[4. Powder]
The powder or granule obtained by the method for producing powder or granule according to an embodiment of the present invention (hereinafter also referred to as "the present powder or granule") has a high degree of circularity (close to 1) and a large bulk specific gravity. It is the body. Due to the large bulk specific gravity of the granular material, transportation tanks and bags can be filled with the granular material at a high density, which can be expected to reduce transportation costs. In addition, if the granular material has a high degree of circularity, the fluidity of the granular material is good, so it is possible to smoothly supply the granular material to the feeder, and the bridge (arch-shaped blockage) It is possible to reduce the risk of this happening. In addition, the present powder, which is a powder with a high degree of circularity (close to 1) and a large bulk specific gravity, is a resin composition obtained by blending a matrix resin and the present powder, or a molded or cured product thereof. It has the advantage that a good dispersion state of the polymer particles can be realized in the product. In the present specification, "powder (powder of fine polymer particles)" may be an aggregate of primary particles of fine polymer particles, in other words, secondary particles of fine polymer particles.

The fineness ratio of granular material can also be determined by the following method. Using a powder suspension as a sample, measure the particle size distribution of the powder in the suspension using a laser diffraction/scattering particle size distribution measuring device LA-950 (manufactured by Horiba, Ltd.) Then, the particle size distribution is determined from the volume cumulative frequency % of powder particles having a volume average particle diameter of 1 μm or more and 3 mm or less. Based on the obtained results, the proportion of powder with a particle size of 50 μm or less in 100% of the powder may be defined as the fine powder ratio (%). The fine powder ratio of the present powder is preferably 8.0% or less, more preferably 7.9% or less, more preferably 7.8% or less, and 7.7% or less. More preferably, it is 7.6% or less, more preferably 7.5% or less, more preferably 7.3% or less, and 7.0% or less. is more preferable, more preferably 6.5% or less, more preferably 6.0% or less, more preferably 5.5% or less, and more preferably 5.0% or less. Preferably, it is 4.5% or less, more preferably 4.0% or less, more preferably 3.5% or less, even more preferably 3.0% or less, Particularly preferably, it is 2.5% or less. When the fineness ratio of the powder or granular material is 8.0% or less, there is an advantage that the risk of dust explosion can be reduced because there is little dust, and there is an advantage that workability is improved.

This granular material has the advantage of high circularity. The circularity of the powder is preferably 0.76 or more, more preferably 0.77 or more, more preferably 0.78 or more, more preferably 0.80 or more, It is more preferably 0.82 or more, and particularly more preferably 0.84 or more. The circularity of the powder or granule can be calculated from an electron micrograph (SEM image) of the powder or granule and the perimeter and area of the powder or granule shown in the electron micrograph. The method for measuring the circularity of powder and granules will be explained in detail in Examples described later. The closer the circularity of the powder or granules is to 1, the better the fluidity of the powder or granules, so that the powder can be smoothly fed to the feeder, and the bridge (occluded in an arch shape) It is possible to reduce the risk of this happening. Moreover, a good dispersion state of the polymer fine particles can be realized in the resin composition obtained by blending the matrix resin and the present powder or granular material, or in the molded product or cured product thereof.

In the present specification, the bulk specific gravity of the powder or granular material is a value measured using a bulk specific gravity measuring device (JIS K-6720 type manufactured by Kuramochi Scientific Instruments Manufacturing Co., Ltd.) based on JIS-K-6720:1999. The bulk specific gravity of the powder or granules is preferably 0.36 g/cm ³ or more, more preferably 0.37 g/cm ³ or more, more preferably 0.38 g/cm ³ or more, It is more preferably 0.39 g/cm ³ or more, more preferably 0.41 g/cm ³ or more, more preferably 0.43 g/cm ³ or more, and more preferably 0.45 g/cm ³ or more. It is more preferable that the amount is 0.47 g/cm 3 or more, and particularly preferably 0.47 g/cm ³ or more. The higher the bulk specific gravity of the powder or granule, the ^more densely aggregated the polymer particles are in the powder or granule. It can be said that it is a granular material with a sufficiently high specific gravity. Further, the upper limit of the bulk specific gravity of the present powder or granular material is not particularly limited, but may be, for example, 1.0 g/cm ³ or less.

The volume average particle diameter of the present powder is not particularly limited, but is preferably, for example, 50 μm to 500 μm, more preferably 100 μm to 400 μm, and even more preferably 200 μm to 350 μm.

EXAMPLES Hereinafter, one embodiment of the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto. One embodiment of the present invention can be modified and implemented as appropriate to the extent that it conforms to the spirit described above or described below, and all of these are included within the technical scope of the present invention.

〔Evaluation methods〕
A method for evaluating the aggregates and powder particles obtained in Examples and Comparative Examples will be described below. Note that the measurement of circularity and bulk specific gravity was performed using powder particles obtained from aggregates obtained by collecting aggregates that fell in the gas phase of the container into a receiving tank, and particles that adhered to the inner wall surface of the coagulation tank. The test was carried out on a mixture of the aggregates obtained by collecting the aggregates into a receiving tank by a flow-down operation, and the powder and granules obtained from the aggregates. The amount of microaggregates is measured by measuring the amount of aggregates obtained without collecting the aggregates attached to the inner wall of the coagulation tank (in other words, by collecting the aggregates that have fallen in the gas phase of the container into the receiving tank). (Only for aggregates).

(Measurement of volume average particle diameter)
The volume average particle diameter (Mv) of the diene rubber (elastic body) or graft copolymer dispersed in the latex was measured using Nanotrac Wave II-EX150 (manufactured by Microtrac Bell Co., Ltd.). Latex diluted with deionized water was used as a measurement sample. For measurement, enter water and the refractive index of the diene rubber (elastic body) or graft copolymer obtained in each production example, measure for 120 seconds, and set the loading index within the range of 1 to 10. The sample concentration was adjusted.

(relative speed difference)
The relative velocity difference between the latex droplets sprayed and/or dripped from the first nozzle and the coagulant solution droplets sprayed and/or dripped from the second nozzle is determined by the visualization laser illumination (CAVILUX Smart The calculation was made from an image obtained by photographing the area irradiated with an ultra-high-speed video camera (Kirana, manufactured by Novitech Co., Ltd.). The area irradiated with visualization laser illumination and photographed with an ultra-high-speed video camera was an area including the intersection of the latex spray direction and the coagulant solution spray direction. For example, in Examples 1, 2, and 4, the first contact step is carried out, and the first nozzle is provided at the top of the container (tower top), and the second nozzle is provided at the side of the container. It was installed on the (inner wall). Therefore, in Examples 1, 2, and 4, the intersection point of the vertical straight line passing through the center of the outlet of the first nozzle and the horizontal straight line passing through the center of the outlet of the second nozzle, The area around the intersection was illuminated with a visualization laser and photographed with an ultra-high-speed video camera. In addition, in Example 3, a second contact step is carried out, and the first nozzle is installed on the side surface (inner wall) of the container, and the second nozzle is installed on the upper part of the container (tower top). was prepared for. Therefore, in Example 3, the intersection of the horizontal straight line passing through the center of the first nozzle's outlet and the vertical straight line passing through the center of the second nozzle's outlet is included; The area was illuminated with laser illumination for visualization and photographed with an ultrahigh-speed video camera. Furthermore, in Comparative Example 1, both the first nozzle and the second nozzle were provided at the top of the container (tower top). Therefore, in Comparative Example 1, the area where both the latex droplet and the coagulant solution droplet were present was irradiated with laser illumination for visualization and photographed with an ultrahigh-speed video camera.

The velocity of the latex droplet and the velocity of the coagulant solution droplet were then calculated from the obtained images, respectively. Specifically, regarding latex droplets, (a) detect droplets moving in the horizontal direction, calculate the velocity of the droplets (referred to as "horizontal - latex velocity"), and (b) detect the droplets moving in the vertical direction. A droplet moving in the direction was detected, and the velocity of the droplet (referred to as "vertical-latex velocity") was calculated. Regarding droplets of coagulant solution, (a) detect droplets moving in the horizontal direction, calculate the velocity of the droplets (referred to as "horizontal - coagulant solution velocity"), and (b) A droplet moving in the vertical direction was detected, and the velocity of the droplet (referred to as "vertical-coagulant solution velocity") was calculated. Next, calculate (a) the speed difference between the horizontal latex speed and the horizontal coagulant solution speed, and (b) the speed difference between the vertical latex speed and the vertical coagulant solution speed, and calculate the difference between the two speeds. The larger value was taken as the relative speed difference between the latex droplet and the coagulant solution droplet in the sample. In calculating the speed difference, the speed with the smaller value was subtracted from the speed with the larger value. That is, the relative speed difference becomes 0 or a positive value.

(Measurement of the amount of microaggregates (%) of aggregates)
Using a suspension containing aggregates obtained in Examples or Comparative Examples as a sample, a laser diffraction/scattering particle size distribution analyzer LA-950 (manufactured by Horiba, Ltd.) was used to measure the concentration of particles in the suspension. The particle size distribution of the aggregates was measured. Next, the particle size distribution was determined from the volume cumulative frequency % of aggregates with volume average particle diameters of 1 μm or more and 3 mm or less. The proportion of aggregates with a particle diameter of 50 μm or less in 100% of the aggregates, calculated based on the obtained results, was defined as the amount of microaggregates (%) of the aggregates.

(Measurement of circularity)
An electron micrograph (SEM image) of the obtained powder was obtained using a scanning electron microscope (SEM, S-3000N manufactured by Hitachi High-Technologies Corporation), and a general-purpose image processing software (product name: NANO The circularity was measured using HUNTER NS2K-PRO/LT (manufactured by Nano System Co., Ltd.). Specifically, the SEM image was imported into the image processing program of the general-purpose image processing software, and the circumferential length and area of the powder and granular material were measured. Circularity was calculated from the obtained perimeter and area according to the following formula. The circularity was calculated for 100 randomly selected powder particles, and the arithmetic average value was taken as the circularity.

(Circularity)=4π×(Area)/(Perimeter) ² .

(Measurement of bulk specific gravity)
The bulk specific gravity of the obtained granular material was measured using a bulk specific gravity measuring device (JIS K-6720 model manufactured by Kuramochi Scientific Instruments Manufacturing Co., Ltd.).

[Production Example 1: Production of emulsion polymerization latex (G-1) of graft copolymer]
200 parts by weight of deionized water was charged into a 100 L polymerization machine (pressure-resistant reaction vessel equipped with a stirrer), and the interior of the polymerization machine was degassed and replaced with nitrogen. After nitrogen substitution, 2.5 parts by weight of sodium oleate, 0.002 parts by weight of ferrous sulfate (FeSO _{4.7H 2} O), and ethylenediaminetetraacetic acid (hereinafter referred to as EDTA) were added to the polymerization machine while stirring.・2Na salt 0.01 part by weight, sodium formaldehyde sulfoxylate 0.2 part by weight, tripotassium phosphate 0.2 part by weight, butadiene 100 parts by weight, divinylbenzene 0.5 part by weight and diisopropylbenzene hydroperoxide 0 .1 part by weight was charged.

Polymerization was carried out at 40°C for 10 hours, and then held at 60°C for 4 hours, to obtain diene rubber latex (R-1) containing diene rubber (elastic body). The polymerization conversion rate was 98%, the volume average particle diameter of the elastic body was 0.08 μm, and the solid content concentration of the diene rubber latex (R-1) was 32.5%.

Next, 215.4 parts by weight (solid) of the diene rubber latex (R-1) was added to a glass reactor equipped with a thermometer, a stirrer, a reflux condenser, a nitrogen inlet, and a device for adding monomers and emulsifiers. 70 parts by weight (as elastic body), 50 parts by weight of water, 0.004 parts by weight of ferrous sulfate ( _FeSO4.7H2O ), 0.005 parts by weight of EDTA/ _2Na salt, sodium formaldehyde sulfoxylate 0.1 part by weight was added. After mixing the input raw materials, the temperature of the mixture was raised to 60°C.

Thereafter, a mixed solution of 22 parts by weight of methyl methacrylate (MMA), 3 parts by weight of styrene, 5 parts by weight of butyl acrylate and 0.1 part by weight of cumene hydroperoxide was continuously added to the glass reactor over a period of 4 hours. After continuing the polymerization for an additional hour, the polymerization was terminated to obtain an emulsion polymerization latex (G-1) containing the graft copolymer as fine polymer particles. The volume average particle diameter of the graft copolymer (polymer fine particles) was 0.23 μm. The concentration of polymer fine particles (solid content concentration) in the emulsion polymerization latex was 35% by weight.

[Production Example 2: Production of hard inelastic polymer latex (P-1)]
200 parts by weight of deionized water, 0.3 parts by weight of sodium oleate, 0.002 parts by weight of ferrous sulfate ( _FeSO4.7H2O ), 0.005 parts by weight of EDTA/ _2Na salt, sodium formaldehyde sulfoxylate 0.2 parts by weight was charged into a 100 L polymerization machine (pressure-resistant reaction vessel equipped with a stirrer). The temperature inside the container was raised to 70° C. while stirring. Thereafter, a monomer mixture consisting of 45 parts by weight of methyl methacrylate, 45 parts by weight of styrene, 10 parts by weight of 1,3-butylene glycol dimethacrylate, and 0.3 parts by weight of cumene hydroperoxide was added to the contents in the polymerization machine. The addition was continued over 7 hours. During this time, 0.3 parts by weight of sodium oleate was added at 2nd, 4th and 6th hours from the start of continuous addition. After the continuous addition of the monomer mixture was completed, the contents were continued to be stirred for another 2 hours to obtain a hard inelastic polymer latex (P-1). The polymerization conversion rate was 99%.

[Example 1: Production of aggregates and powders]
1000 g of emulsion polymerization latex (G-1) (350 g of polymer fine particles in the latex, this 350 g is 100 parts by weight) was taken and the temperature was adjusted to 25°C. The apparatus used was a device comprising a cylindrical container with a vertical inner wall and a receiving tank at the bottom with an aqueous phase region for collecting aggregates generated in the gas phase region. The diameter of the cylindrical container was 80 cm and the height was 100 cm. As the first nozzle, a swirling flow type conical nozzle, which is a type of pressure nozzle, and had a nozzle diameter of 0.6 mm was used. The first nozzle was provided at the top of the container (tower top). The vertical distance between the first nozzle and the bottom of the container (the liquid level in the receiving tank) was 100 cm. Using the first nozzle, the emulsion polymerized latex was sprayed vertically downward at a spray pressure of 3.7 kg/cm ² as droplets with a volume average droplet diameter of 200 μm under a 25°C atmosphere (i.e. inside a container). The temperature was 25°C). The shape of the spray cone of the sprayed latex was a full cone, and the tip angle was 50° to 60°.

At the same time as spraying the latex, a calcium chloride aqueous solution with a calcium chloride concentration of 35% by weight is mixed with air as a coagulant solution using a second nozzle at a spray pressure of 4.0 kg/ ^cm2 . In this state, the liquid was sprayed horizontally at a volume average droplet diameter of 0.10 μm to 30.00 μm. Here, as the second nozzle, a two-fluid nozzle with a nozzle diameter of 0.5 mm was used. The second nozzle was installed on the side surface (inner wall) of the container at a position below the first nozzle so as to spray the coagulant solution horizontally. The horizontal distance between the first and second nozzles was 45 cm, and the vertical distance between the first and second nozzles was 20 cm. The amount of the coagulant solution sprayed was such that the amount of calcium chloride, which is a coagulant, was 5 to 10 parts by weight per 100 parts by weight of the polymer particles in the latex sprayed per unit time. The temperature of the coagulant solution was 25°C. Further, the shape of the spray cone of the sprayed coagulant solution was flat, and the tip angle was 70° to 90°. Through this operation, the latex sprayed into the gas phase was brought into contact with the coagulant solution, and aggregates were obtained. That is, in Example 1, the first contact step was implemented as the contact step. Additionally, the relative velocity difference between the latex droplet and the coagulant solution droplet was calculated. In Example 1, the relative velocity difference was specifically the velocity difference between the vertical-latex velocity and the vertical-coagulant solution velocity.

A calcium chloride aqueous solution (25° C.) with a calcium chloride concentration of 1% by weight was used as the aqueous phase in the receiving tank for collecting the aggregates. Furthermore, in order to prevent fusion between the fine polymer particles, 1 part by weight of hard inelastic polymer latex (P-1) was added to the aqueous calcium chloride solution in the receiver tank per 100 parts by weight of the fine polymer particles.

The aggregates generated by the contact between the droplets of the emulsion polymerized latex and the droplets of the coagulant solution and descended in the gas phase of the container were allowed to descend into the receiving tank provided with the aqueous phase. By blowing steam into the slurry containing aggregates in the receiving tank, the temperature of the slurry was raised to 95°C, and the temperature of the slurry was held at 95°C for 5 minutes (heat treatment), and then the heat-treated slurry was recovered from the receiving tank. (Recovery process). The collected slurry after the heat treatment was dehydrated by suction filtration, and the resulting aggregates were dried in a drier at 60° C. for 1 hour or more to obtain powder (drying step). The amount of microaggregates of the collected aggregates, as well as the circularity and bulk specific gravity of the obtained powder and granules were measured. The results are shown in Table 1.

The contact step was carried out while constantly flowing down the same amount of water as the amount of latex sprayed per unit time along the inner wall surface of the container (flowing operation). In the measurement of circularity and bulk specific gravity, the flowing sewage was collected in a receiving tank, and the aggregates that fell in the gas phase of the container and the aggregates that adhered to the inner wall of the coagulation tank and were collected in the receiving tank by the flow down operation were collected. The test was carried out on powder and granules obtained from a mixture with aggregates. In measuring the recovery rate, the flowing sewage water was not collected in the receiving tank, but only the aggregates that had fallen in the gas phase of the container were measured.

[Example 2: Production of aggregates and powder particles]
Same as Example 1 except that the horizontal distance between the first nozzle and the second nozzle was changed to 20 cm, and the vertical distance between the first nozzle and the second nozzle was changed to 45 cm. Aggregates and powder were obtained by the method. That is, in Example 2, the first contact step was implemented as the contact step. Additionally, the relative velocity difference between the latex droplet and the coagulant solution droplet was calculated. In Example 2, the relative velocity difference was specifically the velocity difference between the vertical-latex velocity and the vertical-coagulant solution velocity. Next, the amount of microaggregates of the collected aggregates, and the circularity and bulk specific gravity of the obtained powder were measured. The results are shown in Table 1.

[Example 3: Production of aggregates and powders]
The same device, first nozzle, and second nozzle as in Example 1 were used. A second nozzle was provided at the top of the vessel (tower top). The vertical distance between the second nozzle and the bottom of the container (liquid level in the receiving tank) was 100 cm. The first nozzle was installed on the side surface (inner wall) of the container, below the second nozzle, and so as to be able to spray latex horizontally. The vertical distance between the first nozzle and the bottom of the container (the liquid level in the receiving tank) was 80 cm. The horizontal distance between the first nozzle and the second nozzle is 45 cm, and the vertical distance between the first nozzle and the second nozzle is at a height of 1 m from the liquid level of the bottom receiving tank. was 20 cm.

1000 g of emulsion polymerization latex (G-1) (350 g of polymer fine particles in the latex, this 350 g is 100 parts by weight) was taken and the temperature was adjusted to 25°C. Using the first nozzle, the emulsion polymerized latex was sprayed horizontally as droplets with a volume average droplet diameter of 200 μm at a spray pressure of 3.7 kg/cm ² in an atmosphere of 25°C (i.e., the temperature inside the container was sprayed at 25°C). The shape of the spray cone of the sprayed latex was a full cone, and the tip angle was 50° to 60°.

At the same time as spraying the latex, a calcium chloride aqueous solution with a calcium chloride concentration of 35% by weight is mixed with air as a coagulant solution using a second nozzle at a spray pressure of 4.0 kg/ ^cm2 . In this state, the liquid was sprayed vertically downward at a volume average droplet diameter of 0.10 μm to 30.00 μm. The amount of the coagulant solution sprayed was such that the amount of calcium chloride, which is a coagulant, was 5 to 10 parts by weight per 100 parts by weight of the polymer particles in the latex sprayed per unit time. The temperature of the coagulant solution was 25°C. Further, the shape of the spray cone of the sprayed coagulant solution was flat, and the tip angle was 70° to 90°. Through this operation, the latex sprayed into the gas phase was brought into contact with the coagulant solution, and aggregates were obtained. That is, in Example 3, the second contact step was implemented as the contact step. Additionally, the relative velocity difference between the latex droplet and the coagulant solution droplet was calculated. In Example 3, the relative velocity difference was specifically the velocity difference between horizontal-latex velocity and horizontal-coagulant solution velocity.

Subsequently, a collection step and a drying step were performed in the same manner as in Example 1 to obtain aggregates and powder. The amount of microaggregates of the collected aggregates, as well as the circularity and bulk specific gravity of the obtained powder and granules were measured. The results are shown in Table 1.

[Example 4: Production of aggregates and powders]
Aggregates and powder were obtained by the same method as in Example 1, except that the vertical distance between the first nozzle and the second nozzle was changed to 55 cm. That is, in Example 4, the first contact step was implemented as the contact step. Additionally, the relative velocity difference between the latex droplet and the coagulant solution droplet was calculated. In Example 4, the relative velocity difference was specifically the velocity difference between the vertical-latex velocity and the vertical-coagulant solution velocity. Next, the amount of microaggregates of the collected aggregates, and the circularity and bulk specific gravity of the obtained powder were measured. The results are shown in Table 1.

[Comparative Example 1: Production of aggregates and powders]
The same device, first nozzle, and second nozzle as in Example 1 were used. As in Example 1, the first nozzle was provided at the top of the container (tower top). The vertical distance between the first nozzle and the bottom of the container (the liquid level in the receiving tank) was 100 cm. A second nozzle was provided at the top of the container (tower top). The vertical distance between the second nozzle and the bottom of the container (liquid level in the receiving tank) was 100 cm. That is, the vertical distance between the first nozzle and the second nozzle was 0 cm. Further, the horizontal distance between the first nozzle and the second nozzle (the horizontal distance between the center of the outlet of the first nozzle and the center of the outlet of the second nozzle) was 45 cm. Ta.

1000 g of emulsion polymerization latex (G-1) (350 g of polymer fine particles in the latex, this 350 g is 100 parts by weight) was taken and the temperature was adjusted to 25°C. Using the first nozzle, the emulsion polymerized latex was sprayed vertically downward at a spray pressure of 3.7 kg/cm ² as droplets with a volume average droplet diameter of 200 μm under a 25°C atmosphere (i.e. inside a container). The temperature was 25°C). The shape of the spray cone of the atomized latex was a full cone, and the tip angle was 50° to 60°.

At the same time as spraying the latex, a calcium chloride aqueous solution with a calcium chloride concentration of 35% by weight is mixed with air as a coagulant solution using a second nozzle at a spray pressure of 4.0 kg/ ^cm2 . In this state, the liquid was sprayed vertically downward at a volume average droplet diameter of 0.10 μm to 30.00 μm. The amount of the coagulant solution sprayed was such that the amount of calcium chloride, which is a coagulant, was 5 to 10 parts by weight per 100 parts by weight of the polymer particles in the latex sprayed per unit time. Further, the shape of the spray cone of the sprayed coagulant solution was flat, and the tip angle was 70° to 90°. Through this operation, the latex sprayed into the gas phase was brought into contact with the coagulant solution, and aggregates were obtained. Additionally, the relative velocity difference between the latex droplet and the coagulant solution droplet was calculated. In Comparative Example 1, the relative velocity difference was specifically the velocity difference between the horizontal-latex velocity and the horizontal-coagulant solution velocity.

Subsequently, a collection step and a drying step were performed in the same manner as in Example 1 to obtain aggregates and powder. The amount of microaggregates of the collected aggregates, as well as the circularity and bulk specific gravity of the obtained powder and granules were measured. The results are shown in Table 1.

[Comparative Example 2: Production of aggregates and powders]
Same as Example 3 except that the horizontal distance between the first nozzle and the second nozzle was changed to 20 cm, and the vertical distance between the first nozzle and the second nozzle was changed to 45 cm. An attempt was made to obtain aggregates and powder by this method. However, the outlet of the first nozzle was blocked, and latex could not be sprayed from the first nozzle. Therefore, it was not possible to obtain aggregates and powder.

According to one embodiment of the present invention, it is possible to produce an aggregate capable of producing a powder or granule having excellent powder properties from latex containing fine polymer particles. Therefore, the manufacturing method according to an embodiment of the present invention can be used for adhesives, coating materials, binders for reinforcing fibers, composite materials, modeling materials for 3D printers, sealants, electronic substrates, ink binders, wood chip binders, and rubber chips. It can be suitably used as a step in the production of resin compositions that are preferably used for applications such as binders, foam chip binders, foundry binders, rock solidifying materials for flooring and ceramics, and urethane foams.

Claims (9)

A latex of polymer fine particles is sprayed and/or dropped in a vertical direction from a first nozzle, and a coagulant solution is sprayed horizontally from a second nozzle, so that the latex droplets and the coagulant solution are a first contacting step of contacting the coagulant solution vertically from the second nozzle, and spraying the latex horizontally from the first nozzle; a second contacting step of contacting the latex droplet with the coagulant solution droplet,
When a second contact step is included, the horizontal distance between the first nozzle and the second nozzle is equal to the vertical distance between the first nozzle and the second nozzle. Longer than, the method of producing aggregates. In the first contacting step and the second contacting step, the latex droplets are formed in a region where the relative velocity difference between the latex droplets and the coagulant solution droplets is 2.8 m/s or more. The method for producing an aggregate according to claim 1, wherein the droplets of the coagulant solution are brought into contact with each other. including the first contacting step, in the first contacting step, the horizontal distance between the first nozzle and the second nozzle is such that the distance between the first nozzle and the second nozzle is The method for producing an aggregate according to claim 1 or 2, wherein the distance between the aggregates is longer than the vertical distance between the aggregates. The method for producing an aggregate according to any one of claims 1 to 3, wherein the concentration of the polymer fine particles in the latex is 10% to 55% by weight based on 100% by weight of the latex. The aggregate according to any one of claims 1 to 4, wherein the amount of the coagulant sprayed is 1 part by weight to 30 parts by weight based on a total of 100 parts by weight of the sprayed amount and the dropped amount of the polymer fine particles. manufacturing method. The method for producing an aggregate according to any one of claims 1 to 5, wherein the polymer fine particles have an elastic body and a graft portion grafted to the elastic body. The method for producing an aggregate according to claim 6, wherein the elastic body includes one or more selected from the group consisting of diene rubber, (meth)acrylate rubber, and organosiloxane rubber. The graft portion includes, as a structural unit, a structural unit derived from one or more monomers selected from the group consisting of aromatic vinyl monomers, vinyl cyan monomers, and (meth)acrylate monomers. The method for producing an aggregate according to claim 6 or 7, comprising a polymer comprising: A recovery step of recovering the aggregate obtained by the method for producing an aggregate according to any one of claims 1 to 8;
a drying step of drying the collected aggregate;
A method for producing a granular material of polymer fine particles, comprising: