JP7020888B2 - Method for manufacturing polymer particles - Google Patents

Description

The present invention relates to a method for producing polymer particles.

It is known that a polymer dispersion liquid in which polymer particles are dispersed is used in a detergent composition for clothing and the like. As a method for producing such a polymer dispersion, for example, in Patent Document 1, a solution containing cationized starch of a charged substance is prepared, and a monomer and a polymerization initiator are added to the solution to emulsify and polymerize the polymer particles. A polymer dispersion in which polymer particles adsorbed with cationized starch are dispersed on the surface of the main body is obtained, and a surfactant is further mixed with the obtained polymer dispersion, and the residue is distilled by heating and reducing the pressure. It is disclosed to reduce the monomer.

JP-A-2015-117315

In the method for producing a polymer dispersion disclosed in Patent Document 1, since the polymer dispersion contains cationized starch as a charged substance, foaming of the polymer dispersion is suppressed when it is distilled to reduce residual monomers. There is a problem that the production efficiency is low because it is necessary to select the distillation conditions. Further, in order to avoid this problem, when the cationized starch is added after distilling the particle body dispersion liquid in which the polymer particle body is dispersed, there is a problem that the polymer particle body is aggregated.

An object of the present invention is to provide a method for producing polymer particles capable of suppressing aggregation of the polymer particle body when a charged substance is added.

The present invention is a method for producing polymer particles in which a charged substance having a charge opposite to that of the polymer particle body is adsorbed on the surface of the polymer particle body having a charge, wherein the particle body dispersion liquid in which the polymer particle body is dispersed. The charged substance-containing liquid containing the charged substance is flowed and merged with each other, and the merged fluid is circulated through the pores having a pore diameter of 0.03 mm or more and 20 mm or less.

According to the present invention, when a charged substance is added by circulating a fluid in which a flowing particle body dispersion liquid and a charged substance-containing liquid are merged in pores having a pore diameter of 0.03 mm or more and 20 mm or less, respectively. Aggregation of the polymer particle body can be suppressed.

It is a figure which shows the structure of the surface treatment system. It is a partial vertical sectional view of the main part in the micromixer of 1st structure. FIG. 2 is a cross-sectional view taken along the line IIB-IIB in FIG. 2A. It is a vertical sectional view which shows the micro mixer of the 2nd composition. It is sectional drawing of IIIB-IIIB in FIG. 3A. It is sectional drawing of IIIC-IIIC in FIG. 3A. It is a vertical sectional view which shows the modification of the micro mixer of 2nd structure. It is sectional drawing of IVB-IVB in FIG. 4A. It is a vertical sectional view which shows the micro mixer of the 3rd structure. It is a vertical sectional view which shows the modification of the micromixer of 3rd structure. It is a vertical sectional view which shows the other modification of the micromixer of 3rd composition. It is a vertical sectional view which shows the other modification of the micro mixer of 3rd composition. It is a vertical sectional view which shows the micro mixer of the 4th structure.

Hereinafter, embodiments will be described in detail.

The method for producing polymer particles according to an embodiment includes a particle body dispersion liquid preparation step, a distillation step, a charged substance-containing liquid preparation step, and a surface treatment step. Then, in the method for producing polymer particles according to this embodiment, a polymer dispersion liquid in which polymer particles in which a charged substance having a charge opposite to that of the polymer particle body is adsorbed on the surface of a charged polymer particle body is dispersed in a dispersion medium. (Slurry) is obtained.

(Particle body dispersion liquid preparation process)
In the particle body dispersion preparation step, a particle body dispersion in which charged polymer particle bodies are dispersed in a dispersion medium is prepared. Specifically, the monomer and the polymerization initiator are put into a dispersion medium for suspension polymerization or emulsion polymerization.

The polymer particle body dispersed in the particle body dispersion liquid may be an anionic polymer particle body or a cationic polymer particle body. The particle body dispersion may be a mixture of cationic polymer particle bodies in the presence of a large number of anionic polymer particle bodies, or an anionic polymer in the presence of a large number of cationic polymer particle bodies. It may be a mixture of particle bodies.

In the case of the anionic polymer particle body, the anionic polymer particle body may be formed of an anionic polymer composed of an anionic group-containing monomer. Examples of the anionic group-containing monomer include ethylenically unsaturated carboxylic acid or a salt thereof. Here, the "anionic group-containing monomer" in the present application means a monomer having a functional group that ionizes into an anion in a dispersion medium. As used in this application, "(meth) acrylic acid" means acrylic acid or methacrylic acid. Further, "(meth) acrylate" means a salt or ester of acrylic acid or methacrylic acid.

Examples of the ethylenically unsaturated carboxylic acid or a salt thereof include acrylic acid, methacrylic acid, itaconic acid, fumaric acid, maleic acid, 2-acrylamide-2-methylpropanesulfonic acid, and acid phosphoroxyethyl (meth) acrylate. Acid phosphoroxyalkyl (meth) acrylate, acid phosphoroxypolyoxyethylene glycol mono (meth) acrylate, acid phosphoroxypolyoxypropylene glycol (meth) acrylate, etc. Glycol, (meth) acrylate and the like can be mentioned.

As the anionic group-containing monomer constituting the anionic polymer, it is preferable to use one or more of these. The anionic polymer may be a homopolymer or a copolymer.

When the anionic polymer is a copolymer, the monomer constituting the copolymer may contain one or more vinyl compounds other than the anionic group-containing monomer. Examples of such vinyl compounds include (meth) acrylic acid ester, (meth) acrylic acid hydroxyalkyl ester, (meth) acrylamides, (meth) acrylic nitrile, vinyl acetate, styrene and the like.

Examples of the (meth) acrylic acid ester include methyl (meth) acrylic acid, ethyl (meth) acrylic acid, n-propyl (meth) acrylic acid, n-butyl (meth) acrylic acid, and iso- (meth) acrylic acid. Butyl, (meth) tert-butyl acrylate, (meth) n-pentyl acrylate, (meth) n-hexyl acrylate, (meth) n-heptyl acrylate, (meth) n-octyl acrylate, (meth) Examples thereof include 2-ethylhexyl acrylate.

Examples of the (meth) acrylic acid hydroxyalkyl ester include (meth) acrylic acid ω-hydroxyalkyl ester, (meth) acrylic acid 2-hydroxyethyl, (meth) acrylic acid 3-hydroxypropyl, and (meth) acrylic acid 4. -Hydroxybutyl and the like can be mentioned. Of these, 2-hydroxyethyl methacrylate is preferable from the viewpoint of availability.

Examples of (meth) acrylamides include acrylamide, N, N-dimethylacrylamide, diethylacrylamide, acryloylmorpholine, dimethylaminopropylacrylamide, hydroxyethylacrylamide and the like.

The anionic polymer forming the main body of the anionic polymer particles may be composed of both an anionic group-containing monomer and a cationic group-containing monomer, and may be anionic as a whole.

Further, the anionic polymer particle body may be one in which the polymer particles exhibiting cationic or nonionic properties are coated with an anionic substance and exhibit anionic properties as a whole.

In the case of the cationic polymer particle body, the cationic polymer particle body may be formed of a cationic polymer composed of a cationic group-containing monomer. Examples of the cationic group-containing monomer include dialkylamino groups such as dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylamide, and diethylaminopropyl (meth) acrylamide (meth). Examples thereof include acrylic acid esters or (meth) acrylamides, salts or quaternary salts thereof, diallylamine compounds such as diallylmethylamine and diallylamine, and salts or quaternary salts thereof. Here, the "cationic group-containing monomer" in the present application means a monomer having a functional group that ionizes into a cation in a dispersion medium.

As the cationic group-containing monomer constituting the cationic polymer, it is preferable to use one or more of these. The cationic polymer may be a homopolymer or a copolymer. When the cationic polymer is a copolymer, the monomer constituting the copolymer may contain one or more vinyl compounds other than the cationic group-containing monomer. Examples of such vinyl compounds include those similar to those that can be included in the copolymers of anionic polymers described above.

The cationic polymer forming the main body of the cationic polymer particles may be composed of both a cationic group-containing monomer and an anionic group-containing monomer, and may exhibit cationic properties as a whole.

Further, the main body of the cationic polymer particles may be one in which polymer particles exhibiting anionic or nonionic properties are coated with a cationic substance and exhibit cationic properties as a whole.

Examples of the polymerization initiator include 2,2'-azobisisobutyronitrile, 2,2'-azobis (2,4-dimethylvaleronitrile), and 2,2'-azobis (2-amidinopropane) hydrochloride. Azo compounds such as; tert-butylperoxyoctate, organic peroxides such as dibenzoyl peroxide; inorganic peroxides such as sodium persulfate, potassium persulfate, ammonium persulfate and the like can be mentioned. It is preferable to use one or more of these as the polymerization initiator. An azo compound is preferable from the viewpoint of suppressing aggregation of the polymer particle body.

Examples of the dispersion medium used in the particle body dispersion liquid include water. Examples of water include distilled water, deionized water, ultrapure water and the like. The dispersion medium may contain an organic solvent compatible with water as long as it does not affect the polymerization reaction. Examples of such an organic solvent include lower alcohols having 1 to 3 carbon atoms such as methanol, ethanol and isopropyl alcohol, and ketones having 3 or 4 carbon atoms such as acetone and methyl ethyl ketone.

The particle body dispersion may contain an emulsifier, a surfactant, a pH adjuster, or the like in addition to the polymer particle body and the dispersion medium.

The solid content concentration c ₁ in the particle body dispersion is preferably 10% by mass or more, more preferably 20% by mass or more, still more preferably 25% by mass or more, from the viewpoint of suppressing aggregation of the polymer particle body in the surface treatment step. From the same viewpoint, it is preferably 50% by mass or less, more preferably 45% by mass or less, and further preferably 40% by mass or less. The solid content concentration c ₁ in the particle body dispersion is preferably 10% by mass or more and 50% by mass or less, more preferably 20% by mass or more and 45% by mass or less, and further preferably 25% by mass or more and 40% by mass or less.

The Z average particle size of the polymer particle body contained in the particle body dispersion is preferably 10 nm or more, more preferably 30 nm or more, still more preferably 50 nm or more from the viewpoint of suppressing aggregation of the polymer particle body in the surface treatment step. From the same viewpoint, it is preferably 900 nm or less, more preferably 800 nm or less, and further preferably 750 nm or less. The Z average particle diameter of the polymer particle body is preferably 10 nm or more and 900 nm or less, more preferably 30 nm or more and 800 nm or less, and further preferably 50 nm or more and 750 nm or less. Here, the Z average particle size is measured by a dynamic light scattering method (hereinafter, the same applies).

The zeta potential of the polymer particle body contained in the particle body dispersion is smaller than zero in the case of the anionic polymer particle body, while it is larger than zero in the case of the cationic polymer particle body. The absolute value of the zeta potential of the polymer particle body is preferably 1 mV or more, more preferably 5 mV or more, still more preferably 10 mV or more, and the same, from the viewpoint of suppressing aggregation of the polymer particle body in the surface treatment step. From the viewpoint, it is preferably 70 mV or less, more preferably 50 mV or less, still more preferably 40 mV or less. The absolute value of the zeta potential of the polymer particle body is preferably 1 mV or more and 70 mV or less, more preferably 5 mV or more and 50 mV or less, and further preferably 10 mV or more and 40 mV or less. Here, the zeta potential is measured by light scattering electrophoresis (hereinafter, the same applies).

(Distillation process)
In the distillation step, the particle body dispersion prepared in the particle body dispersion preparation step is distilled. At this time, the residual monomer is removed together with the dispersion medium of the volatile component, and the residual monomer in the particle body dispersion liquid is reduced. Here, in the distillation operation, heating and depressurization may be performed. Further, the operation of distilling off the dispersion medium and the residual monomer by distillation to concentrate the particle body dispersion liquid, and then adding the dispersion medium to dilute to the original solid content concentration may be repeated. On the contrary, the operation of adding a dispersion medium to the particle body dispersion liquid to dilute it, distilling off the dispersion medium by distillation, and concentrating to the original solid content concentration may be repeated. From the viewpoint of promoting the diffusion of the residual monomer contained in the polymer particle body into the dispersion medium, the former operation among these is preferable.

In the method for producing a polymer dispersion disclosed in Patent Document 1, since the polymer dispersion contains cationized starch as a charged substance, foaming of the polymer dispersion is suppressed when it is distilled to reduce residual monomers. There is a problem that the production efficiency is low because it is necessary to select the distillation conditions. However, in the method for producing polymer particles according to this embodiment, the particle body dispersion liquid containing no charged substance before being merged with the charged substance-containing liquid is distilled in the pore flow step described later, and therefore disclosed in Patent Document 1. There are no restrictions on the distillation conditions as in the method for producing the obtained polymer dispersion, and therefore, this step can be performed with high production efficiency.

(Preparation process for charged substance-containing liquid)
In the chargeable substance-containing liquid preparation step, a charged substance-containing liquid containing a charged substance having a charge opposite to that of the polymer particle body is prepared. The charged substance-containing liquid may be a solution in which the charged substance is dissolved in a solvent, or may be a dispersion liquid in which the charged substance becomes particles and is dispersed in a dispersion medium, and a part of the charged substance may be. It may be dissolved and partially dispersed as particles. The charged substance-containing liquid may be a mixture of a charged substance having the same charge as the polymer particle body in the presence of a charged substance having a charge opposite to that of the polymer particle body.

When the particle body dispersion liquid contains an anionic polymer particle body, the charged substance adsorbed on the anionic polymer particle body is a cationic group-containing substance. Examples of the cationic group-containing substance include cationized starch, quaternary ammonium salt, cationized poval, and cationized guar gum.

Cationized starch is starch in which a cation group is introduced. The cationized starch can be obtained, for example, by reacting the starch with a quaternary ammonium alkylating reagent. Examples of the starch forming the main skeleton of the cationized starch include corn starch, wheat starch, potato starch, tapioca starch and the like.

Examples of the quaternary ammonium salt include stearyltrimethylammonium chloride, cetyltrimethylammonium bromide, behenyltrimethylammonium chloride, distearyldimethylammonium chloride, tricetylmethylammonium chloride, oxyethylalkylammonium phosphate, and cocoalkylmethylbis (polyethoxyethanol). ) Ammonium chloride, palmitoyl ethyl hydroxyethyl ammonium methyl sulfate, stearyl dimethyl benzyl ammonium chloride and the like can be mentioned.

As the cationic group-containing substance, it is preferable to use one or more of these. From the viewpoint of dispersion stability of particles, cationized starch is preferable.

When the particle body dispersion liquid contains a cationic polymer particle body, the charged substance adsorbed on the cationic polymer particle body is an anionic group-containing substance. Examples of the anionic group-containing substance include poly (meth) acrylic acid, lignin sulfonate, naphthalene sulfonate formaldehyde condensate and the like. As the anionic group-containing substance, it is preferable to use one or more of these.

The cationic group-containing substance constituting the charged substance may contain both a cationic group and an anionic group and may exhibit cationicity as a whole. Similarly, the anionic group-containing substance constituting the charged substance may contain both anionic groups and cationic groups and exhibit anionicity as a whole.

The weight average molecular weight (Mw) of the charged substance is preferably 10,000 or more, more preferably 100,000 or more, still more preferably 1 million or more, and preferably from the same viewpoint, from the viewpoint of dispersion stability of the particles. Is 80 million or less, more preferably 40 million or less, still more preferably 10 million or less. The weight average molecular weight (Mw) in the charged substance-containing liquid is preferably 10,000 or more and 80 million or less, more preferably 100,000 or more and 40 million or less, and further preferably 1 million or more and 10 million or less.

The charged substance-containing liquid may contain a dispersant, a surfactant, a pH adjuster, or the like in addition to the charged substance.

The solid content concentration c ₂ in the charged substance-containing liquid is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, still more preferably 0.5% by mass or more, from the viewpoint of suppressing aggregation of the polymer particle body in the surface treatment step. It is 1% by mass or more, and from the same viewpoint, it is preferably 30% by mass or less, more preferably 10% by mass or less, and further preferably 6% by mass or less. The solid content concentration c ₂ in the charged substance-containing liquid is preferably 0.1% by mass or more and 30% by mass or less, more preferably 0.5% by mass or more and 10% by mass or less, and further preferably 1% by mass or more and 6% by mass or less. Is.

(Surface treatment process)
The surface treatment step consists of a merging step in which the particle body dispersion liquid and the charged substance-containing liquid are each flowed and merged, and the pore circulation in which the merged fluid is circulated to pores having a pore diameter of 0.03 mm or more and 20 mm or less. Has steps and.

<Merge step>
In the merging step, the particle body dispersion liquid and the charged substance-containing liquid are each flowed and merged.

In the particle body dispersion liquid and the charged substance-containing liquid to be merged, the number of moles of the functional group having the charge of the charged substance in the charged substance-containing liquid relative to the number of moles of the charged functional group of the polymer particle body in the particle body dispersion liquid. The ratio (the charged functional group of the charged substance in the charged substance-containing liquid / the charged functional group of the polymer particle body in the particle body dispersion liquid) is from the viewpoint of suppressing the aggregation of the polymer particle body in the merged fluid. It is preferably 0.01 or more, more preferably 0.05 or more, still more preferably 0.1 or more, and from the same viewpoint, it is preferably 50 or less, more preferably 30 or less, still more preferably 20 or less. .. The ratio of the number of moles of the charged functional group in the charged substance-containing liquid to the number of moles of the charged functional group of the polymer body particle in the particle body dispersion is preferably 0.01 or more and 50 or less. It is preferably 0.05 or more and 30 or less, and more preferably 0.1 or more and 20 or less. When the charged functional group of the polymer particle body in the particle body dispersion liquid is a cationic group, the charged functional group of the charged substance in the charged substance-containing liquid is an anionic group. When the charged functional group of the polymer particle body in the particle body dispersion is an anionic group, the charged functional group of the charged substance in the charged substance-containing liquid is a cationic group. Further, when the polymer particle body or the charged substance contains both a cationic group and an anionic group, the number of moles of the functional group having the charge thereof is the difference in the number of moles of the cationic group and the anionic group.

The flow rate _Q1 of the particle body dispersion liquid before merging is preferably 0.1 L / h or more, more preferably 0.3 L / h or more, still more preferably 0.3 L / h or more, from the viewpoint of suppressing aggregation of the polymer particle body in the merged fluid. It is 0.5 L / h or more, and from the same viewpoint, it is preferably 30 L / h or less, more preferably 20 L / h or less, and further preferably 15 L / h or less. The flow rate _Q1 of the particle body dispersion liquid before merging is preferably 0.1 L / h or more and 30 L / h or less, more preferably 0.3 L / h or more and 20 L / h or less, and further preferably 0.5 L / h or more and 15 L. It is less than / h.

The flow rate _Q2 of the charged substance-containing liquid before merging is preferably 0.1 L / h or more, more preferably 0.5 L / h or more, still more preferably 0.5 L / h or more, from the viewpoint of suppressing aggregation of the polymer particle body in the merging fluid. It is 1.0 L / h or more, and from the same viewpoint, it is preferably 30 L / h or less, more preferably 20 L / h or less, and further preferably 15 L / h or less. The flow rate _Q2 of the charged substance-containing liquid before merging is preferably 0.1 L / h or more and 30 L / h or less, more preferably 0.5 L / h or more and 20 L / h or less, and further preferably 1.0 L / h or more and 15 L. It is less than / h.

The flow rate ratio (Q ₁ / Q ₂ ) of the particle body dispersion liquid before merging to the charged substance-containing liquid is preferably 0.01 or more, more preferably 0, from the viewpoint of suppressing aggregation of the polymer particle body in the merging fluid. It is 1.1 or more, more preferably 0.5 or more, and from the same viewpoint, it is preferably 5 or less, more preferably 2 or less, still more preferably 1.5 or less. The flow rate ratio (Q ₁ / Q ₂ ) of the particle body dispersion liquid before merging to the charged substance-containing liquid is preferably 0.01 or more and 5 or less, more preferably 0.1 or more and 2.0 or less, and further preferably 0. 5 or more and 1.5 or less.

It is preferable that the temperatures of the particle body dispersion liquid and the charged substance-containing liquid before merging are the same, and therefore the temperature of the fluid after merging is also the same. The temperature of the particle body dispersion liquid and the charged substance-containing liquid before merging and the fluid after merging thereof is preferably 1 ° C. or higher, more preferably 5 ° C. or higher from the viewpoint of suppressing aggregation of the polymer particle body in the merged fluid. It is more preferably 10 ° C. or higher, and from the same viewpoint, it is preferably 70 ° C. or lower, more preferably 50 ° C. or lower, still more preferably 30 ° C. or lower. The temperature of the particle body dispersion liquid and the charged substance-containing liquid before merging and the fluid after merging thereof is preferably 1 ° C. or higher and 70 ° C. or lower, more preferably 5 ° C. or higher and 50 ° C. or lower, and further preferably 10 ° C. or higher and 30 ° C. It is as follows.

The mode of merging of the particle body dispersion liquid and the charged substance-containing liquid in the merging step is not particularly limited.

The mode of collision (angle, etc.) when the particle body dispersion liquid and the charged substance-containing liquid are merged is, for example, a mode in which both are head-on collided and merged (countercurrent collision resistance), and one is orthogonal to the other. A mode in which one collides with the other from diagonally behind to merge, a mode in which one collides with the other diagonally from the front and merges, and a mode in which one is brought into contact along the other to merge. An embodiment in which one is made to collide from the entire circumference of the other and merged can be mentioned. Of these, from the viewpoint of suppressing the aggregation of the polymer particle bodies in the merged fluid, it is preferable to collide one of them from the entire circumference of the other to merge them.

As the mode (number, etc.) of the merging method when merging the particle body dispersion liquid and the charged substance-containing liquid, both are collided from a plurality of directions to be merged, and one is made to collide with the other from a plurality of directions. There is an embodiment of merging. In the former, it is preferable to collide both of them from two or more directions, and it is preferable to collide from four or less directions from the viewpoint of productivity, although there is no particular upper limit. In the latter, it is preferable to collide one with the other from two or more directions, and it is preferable to collide one with the other from four directions or less from the viewpoint of productivity, although there is no particular upper limit.

After at least one of the particle body dispersion liquid and the charged substance-containing liquid is circulated in the pores having the same structure as the pores through which the fluid merged in the pore flow step described later is circulated, or in the pores. They may be distributed and merged.

<Pore distribution step>
In the pore circulation step, the fluid merged in the merging step is circulated in the pores having a pore diameter of 0.03 mm or more and 20 mm or less.

According to the method for producing polymer particles according to the embodiment, a fluid in which a flowing particle body dispersion liquid and a charged substance-containing liquid are merged is circulated in pores having a pore diameter of 0.03 mm or more and 20 mm or less, respectively, to be charged. It is possible to suppress the aggregation of the polymer particle body when the substance is added. This is due to adsorption in a non-uniformly mixed state because the fluid in which the particle body dispersion liquid and the charged substance-containing liquid are combined is circulated through the pores, and the adsorption starts after they are rapidly and uniformly mixed. This is thought to be because aggregation can be suppressed.

Examples of the cross-sectional shape of the pores include a circle, a semicircle, an ellipse, a semi-elliptical shape, a square, a rectangle, a trapezoid, a parallelogram, a star shape, an irregular shape, and the like. Of these, a circular shape is preferable from the viewpoint of suppressing aggregation of the polymer particle body in the merged fluid. The cross-sectional shape of the pores is preferably the same along the length direction.

The direction in which the pores extend is preferably the same as at least one of the flow direction of the particle body dispersion liquid and the flow direction of the charged substance-containing liquid from the viewpoint of suppressing aggregation of the polymer particle body in the merged fluid.

The pore diameter of the pores is 0.03 mm or more and 20 mm or less. The pore diameter is preferably 0.04 mm or more, more preferably 0.05 mm or more, still more preferably 0.1 mm or more, still more preferably 0. It is 15 mm or more, and from the same viewpoint, it is preferably 10 mm or less, more preferably 5 mm or less, still more preferably 3 mm or less, still more preferably 1 mm or less. The pore diameter of the pores is preferably 0.04 mm or more and 10 mm or less, more preferably 0.05 mm or more and 5 mm or less, still more preferably 0.1 mm or more and 3 mm or less, and further preferably 0.15 mm or more and 1 mm or less. The diameter of the pores is the diameter when the cross-sectional shape of the pores is circular, but the equivalent hydraulic diameter (4 x channel area / cross-sectional length) when the cross-sectional shape of the pores is non-circular. ).

The length of the pores is preferably 0.05 mm or more, more preferably 0.1 mm or more, still more preferably 0.3 mm or more, and the same, from the viewpoint of suppressing aggregation of the polymer particle body in the merged fluid. From the viewpoint of the above, it is preferably 10 mm or less, more preferably 5 mm or less, still more preferably 2 mm or less. The length of the pores is preferably 0.05 mm or more and 10 mm or less, more preferably 0.1 mm or more and 5 mm or less, and further preferably 0.3 mm or more and 2 mm or less.

The ratio (length / pore diameter) of the pore length to the pore diameter is preferably 0.1 or more, more preferably 0.5 or more, still more preferably 0.5 or more, from the viewpoint of suppressing the aggregation of the polymer particle body in the merged fluid. It is 1 or more, and from the same viewpoint, it is preferably 30 or less, more preferably 10 or less, and further preferably 5 or less. The ratio (length / pore diameter) of the pore length to the pore diameter is preferably 0.1 or more and 30 or less, more preferably 0.5 or more and 10 or less, and further preferably 1 or more and 5 or less.

The flow path area of the pores is preferably 0.005 mm ² or more, more preferably 0.01 mm ² or more, still more preferably 0.02 mm ² or more, from the viewpoint of suppressing aggregation of the polymer particle body in the merged fluid. From the same viewpoint, it is preferably 20 mm ² or less, more preferably 5 mm ² or less, still more preferably 1 mm ² or less, still more preferably 0.5 mm ² or less. The flow path area of the pores is preferably 0.005 mm ² or more and 20 mm ² or less, more preferably 0.005 mm ² or more and 5 mm ² or less, still more preferably 0.01 mm ² or more and 1 mm ² or less, still more preferably 0.02 mm. ² or more and 0.5 mm ² or less.

The method of circulating the fluid in which the particle body dispersion liquid and the charged substance-containing liquid are merged through the pores is to make the particle body dispersion liquid and the charged substance-containing liquid pores from the viewpoint of suppressing the aggregation of the polymer particle body in the merged fluid. A method of merging immediately before the merging and allowing the fluid immediately after the merging to flow through the pores as it is, or a method of merging the particle body dispersion liquid and the charged substance-containing liquid in the pores and continuously flowing the merged fluid through the pores. The method of making the particles is preferable. In addition, a method may be used in which the particle body dispersion liquid and the charged substance-containing liquid are once merged at the liquid reservoir, and the fluid in which they are in a mixed state is circulated in the pores.

The ratio of the content m ₂ of the charged substance to the content m ₁ of the polymer particle body in the fluid flowing through the pores, that is, (m ₂ / m ₁ ) × 100 suppresses the aggregation of the polymer particle body in the merged fluid. From the viewpoint of the above, it is preferably 1% by mass or more, more preferably 5% by mass or more, still more preferably 8% by mass or more, and from the same viewpoint, preferably 30% by mass or less, more preferably 20% by mass or less. , More preferably 18% by mass or less. The ratio of the content m ₂ of the charged substance to the content m ₁ of the polymer particle body in the fluid flowing through the pores is preferably 1% by mass or more and 30% by mass or less, more preferably 5% by mass or more and 20% by mass or less. More preferably, it is 8% by mass or more and 18% by mass or less.

The flow rate Q of the fluid flowing through the pores is preferably 0.1 L / h or more, more preferably 0.5 L / h or more, still more preferably 1. It is 0 L / h or more, and from the same viewpoint, it is preferably 50 L / h or less, more preferably 40 L / h or less, and further preferably 25 L / h or less. The flow rate Q of the fluid flowing through the pores is preferably 0.1 L / h or more and 50 L / h or less, more preferably 0.5 L / h or more and 40 L / h or less, and further preferably 1.0 L / h or more and 25 L / h or less. It is as follows.

The flow velocity u of the fluid flowing through the pores is preferably 5 m / s or more, more preferably 7 m / s or more, still more preferably 10 m / s or more, from the viewpoint of suppressing aggregation of the polymer particle body in the merged fluid. From the same viewpoint, it is preferably 40 m / s or less, more preferably 30 m / s or less, and further preferably 22 m / s or less. The flow velocity u of the fluid flowing through the pores is preferably 5 m / s or more and 40 m / s or less, more preferably 7 m / s or more and 30 m / s or less, and further preferably 10 m / s or more and 22 m / s or less. The flow velocity u of the fluid flowing through the pores can be controlled by the flow rate Q of the fluid flowing through the pores.

From the viewpoint of suppressing the aggregation of the polymer particle body in the merged fluid, the fluid flowing through the pores is preferably circulated under turbulent flow conditions. The Reynolds number Re of the fluid flowing through the pores is preferably 5000 or more, more preferably 10,000 or more, still more preferably 60,000 or more, and the same, from the viewpoint of suppressing the aggregation of the polymer particle body in the merged fluid. From the viewpoint, it is preferably 200,000 or less, more preferably 150,000 or less, still more preferably 100,000 or less. The Reynolds number Re of the fluid flowing through the pores is preferably 5,000 or more and 200,000 or less, more preferably 10,000 or more and 150,000 or less, and further preferably 60,000 or more and 100,000 or less. Here, the Reynolds number Re of the fluid flowing through the pores is the average flow velocity u (m / s) of the fluid in the pores, the pore diameter d (m), the viscosity μ (Pa · s) of the fluid, and so on. And, it is obtained by a general Reynolds number calculation formula (Reynolds number Re = duρ / μ) of the pipe flow using the value of the fluid density ρ (kg / m ³ ).

The pressure loss ΔP before and after the pores is the pressure difference before and after the pore flow, and the size of the jet can be evaluated by this. This pressure loss ΔP is preferably 0.01 MPa or more, more preferably 0.05 MPa or more, still more preferably 0.1 MPa or more, and is excessive, from the viewpoint of suppressing aggregation of the polymer particle body in the merged fluid. From the viewpoint of preventing pressure loss ΔP from occurring and causing damage to the equipment, the pressure loss is preferably 5 MPa or less, more preferably 1 MPa or less, still more preferably 0.8 MPa or less. The pressure loss ΔP is preferably 0.01 MPa or more and 5 MPa or less, more preferably 0.05 MPa or more and 1 MPa or less, and further preferably 0.1 MPa or more and 0.8 MPa or less.

From the viewpoint of suppressing the aggregation of the polymer particle body in the merged fluid, it is preferable to allow the fluid flowing through the pores to flow out to the channel expansion portion where the channel diameter is expanded to facilitate turbulence.

Examples of the cross-sectional shape of the flow path of the flow path expansion portion include a circle, a semicircle, an ellipse, a semi-elliptical shape, a square, a rectangle, a trapezoid, a parallelogram, a star shape, and an indefinite shape. Of these, the circular shape is preferable from the viewpoint of suppressing the aggregation of the polymer particle body in the merged fluid. The cross-sectional shape of the flow path enlarged portion is preferably the same along the length direction, but may include different shapes along the length direction.

The flow path expanding portion is preferably formed so as to expand in a cone shape from the pores to the portion having the maximum flow path diameter from the viewpoint of suppressing the aggregation of the polymer particle body in the merged fluid. This cone enlargement angle (θ ₁₂ in FIG. 2A) is preferably 80 ° or more, more preferably 90 ° or more, still more preferably 100 ° or more, from the viewpoint of suppressing aggregation of the polymer particle body in the merged fluid. From the same viewpoint, it is preferably 180 ° or less, more preferably 170 ° or less, and further preferably 140 ° or less. The cone enlargement angle is preferably 80 ° or more and 180 ° or less, more preferably 90 ° or more and 170 ° or less, and further preferably 100 ° or more and 140 ° or less.

The maximum flow path diameter of the flow path expanding portion is preferably 2 times or more, more preferably 3 times or more, still more preferably 5 times or more the pore diameter of the pores from the viewpoint of suppressing aggregation of the polymer particle body in the merged fluid. Also, from the same viewpoint, it is preferably 40 times or less, more preferably 20 times or less, still more preferably 12 times or less. The maximum flow path diameter of the flow path enlarged portion is preferably 2 times or more and 40 times or less, more preferably 3 times or more and 20 times or less, and further preferably 5 times or more and 12 times or less the pore diameter of the pores. The maximum diameter of the flow path enlarged portion is the diameter when the cross-sectional shape of the flow path is circular, but is the equivalent hydraulic diameter when the cross-sectional shape of the flow path is non-circular.

The operation of flowing the fluid in which the particle body dispersion liquid and the charged substance-containing liquid are merged into the pores is a segregation index (Segregation index (Segregation index), which is obtained by a method described later from the viewpoint of suppressing aggregation of the polymer particle body in the merged fluid. Xs)) is preferably 0.1 or less, more preferably 0.01 or less, still more preferably 0.004 or less. Although there is no particular lower limit, 0.0001 or more is sufficient, and 0.001 or more may be sufficient.

Here, the segregation index (Xs) indicates the mixing and stirring effect of the particle body dispersion liquid and the charged substance-containing liquid in the method for producing polymer particles according to the embodiment, and the smaller the value, the higher the mixing property. show. The segregation index (Xs) is an index that is academically used for general purpose evaluation of mixing performance of mixers, and can be derived from the following equation using Villermaux / Dushman reaction. For details of this reaction system, refer to P.I. Guichardon and L. Falk, Chemical Engineering Science 55 (2000) 4233-4243.

Specifically, first, 0.171N sulfuric acid and boric acid buffer are prepared as two aqueous solutions that react by mixing. The composition of the boric acid buffer is 0.045 mol / L of boric acid, 0.045 mol / L of sodium hydroxide, 0.00313 mol / L of potassium iodine, and 0.0156 mol / L of potassium iodine. Then, when these two liquids are mixed, the following neutralization reaction (I) and the redox reaction (II) produced by iodine proceed at the same time. The mixing of the two liquids is carried out under the condition that the boric acid buffer solution becomes excessive in the state after mixing.

<Surface treatment system S>
FIG. 1 shows an example of a surface treatment system S that can be used in a surface treatment step in the method for producing polymer particles according to an embodiment. In the following, one of the first and second liquids will be a particle body dispersion liquid and the other will be a charged substance-containing liquid.

The surface treatment system S is composed of a micromixer 100 and an accessory portion such as a fluid supply system.

2A and 2B show the micromixer 100 having the first configuration.

The micromixer 100 having the first configuration includes a fluid flow path portion 10, a fluid confluence confluence section 20 continuously provided on the downstream side thereof, and a fluid outflow section 30 continuously provided on the downstream side thereof. And.

The fluid flow path portion 10 has a small diameter pipe 11 and a large diameter pipe 12. The large-diameter pipe 12 accommodates the small-diameter pipe 11, which have a common length direction and are arranged coaxially. As a result, the fluid flow path portion 10 is configured with the first flow path 11a inside the small diameter pipe 11 and the second flow path 12a inside the large diameter pipe 12 and outside the small diameter pipe 11. The first flow path 11a in the small diameter tube 11 communicates with the first liquid supply unit 101 provided at one end of the device, and the second flow path 12a in the large diameter tube 12 is provided on the side surface of the device. It communicates with the second liquid supply unit 102.

The outer shape of the small diameter tube 11 and the cross-sectional shape of the hole are not particularly limited, and are, for example, circular, semi-circular, elliptical, semi-elliptical, square, rectangular, trapezoidal, parallelogram, star-shaped, and amorphous. And so on. The cross-sectional shape of the hole of the large-diameter tube 12 is not particularly limited, and like the small-diameter tube 11, for example, circular, semi-circular, elliptical, semi-elliptical, square, rectangular, trapezoidal, parallelogram, etc. It may be a star shape, an indefinite shape, or the like. However, the outer shape and the cross-sectional shape of both the outer shape and the hole of the small diameter tube 11 and the hole of the large diameter tube 12 are preferably circular from the viewpoint of suppressing the aggregation of the polymer particle body in the merged fluid. Further, it is preferable that the small-diameter pipe 11 and the large-diameter pipe 12 are provided so that the cross-sectional shapes are symmetrical and coaxial from the viewpoint of suppressing the aggregation of the polymer particle body in the merged fluid. Therefore, as shown in FIG. 2B, the small-diameter pipe 11 and the large-diameter pipe 12 have a circular cross-sectional shape of the first flow path 11a and a donut-shaped cross-sectional shape of the second flow path 12a. It is preferable that the configuration is provided.

Both the outer shape and the cross-sectional shape of the hole of the small-diameter pipe 11 have the same shape along the length direction except for the pipe end portion 11b described later, from the viewpoint of suppressing the aggregation of the polymer particle body in the merged fluid. Is preferable. The cross-sectional shape of the hole of the large-diameter pipe 12 is also the same along the length direction from the viewpoint of suppressing the aggregation of the polymer particle body in the merged fluid, except for the portion corresponding to the pipe end portion 11b of the small-diameter pipe 11. The shape is preferable.

When both the outer shape and the cross-sectional shape of the hole of the small diameter tube 11 are circular, the outer diameter D ₁₁ is preferably 1.6 mm or more, more preferably, from the viewpoint of suppressing aggregation of the polymer particle body in the merged fluid. Is 2 mm or more, and from the same viewpoint, it is preferably 25 mm or less, more preferably 15 mm or less, still more preferably 10 mm or less, still more preferably 4 mm or less. The outer diameter D ₁₁ is preferably 1.6 mm or more and 25 mm or less, more preferably 2 mm or more and 15 mm or less, still more preferably 2 mm or more and 10 mm or less, still more preferably 2 mm or more and 4 mm or less.

The inner diameter D ₁₂ of the small diameter tube 11, that is, the flow path diameter of the first flow path 11a is preferably 0.8 mm or more, more preferably 1 mm or more, from the viewpoint of suppressing aggregation of the polymer particle body in the merged fluid. From the same viewpoint, it is preferably 20 mm or less, more preferably 10 mm or less, still more preferably 5 mm or less, still more preferably 3 mm or less. The inner diameter D ₁₂ is preferably 0.8 mm or more and 20 mm or less, more preferably 1 mm or more and 10 mm or less, still more preferably 1 mm or more and 5 mm or less, still more preferably 1 mm or more and 3 mm or less.

When the cross-sectional shape of the hole of the large-diameter tube 12 is circular, the inner diameter D ₁₃ is preferably 1.8 mm or more, more preferably 4 mm or more, from the viewpoint of suppressing aggregation of the polymer particle body in the merged fluid. Also, from the same viewpoint, it is preferably 50 mm or less, more preferably 20 mm or less, still more preferably 10 mm or less, still more preferably 6 mm or less. The inner diameter D ₁₃ is preferably 1.8 mm or more and 50 mm or less, more preferably 4 mm or more and 20 mm or less, still more preferably 4 mm or more and 10 mm or less, still more preferably 4 mm or more and 6 mm or less.

The gap Δ1 of the _second flow path 12a between the small diameter tube 11 and the large diameter tube 12 is preferably 0.1 mm or more, more preferably 0.3 mm, from the viewpoint of suppressing aggregation of the polymer particle body in the merged fluid. As described above, it is more preferably 0.7 mm or more, and from the same viewpoint, it is preferably 12.5 mm or less, more preferably 6 mm or less, still more preferably 3 mm or less, still more preferably 1 mm or less. The gap Δ ₁ is preferably 0.1 mm or more and 12.5 mm or less, more preferably 0.3 mm or more and 6 mm or less, still more preferably 0.7 mm or more and 3 mm or less, still more preferably 0.7 mm or more and 1 mm or less.

As shown in FIG. 2A, the outer peripheral portion of the tube end portion 11b on the downstream side of the small-diameter tube 11 is preferably formed in a tapered shape from the viewpoint of suppressing aggregation of the polymer particle body in the merged fluid. It is more preferable that the cross-sectional shape in the thickness direction is formed into a sharp spire shape on the inner peripheral side.

The gap δ ₁ which is a part of the second flow path 12a formed between the inner wall of the large-diameter pipe 12 and the pipe end portion 11b of the small-diameter pipe 11 is a viewpoint of suppressing aggregation of the polymer particle body in the merged fluid. Therefore, it is preferable that the fluid flow direction is uniform. The gap δ ₁ is preferably 0.02 mm or more, more preferably 0.05 mm or more, still more preferably 0.1 mm or more, and the same, from the viewpoint of suppressing aggregation of the polymer particle body in the merged fluid. From the viewpoint, it is preferably 12.5 mm or less, more preferably 6 mm or less, still more preferably 1 mm or less, still more preferably 0.40 mm or less. The gap δ ₁ is preferably 0.02 mm or more and 12.5 mm or less, more preferably 0.05 mm or more and 6 mm or less, still more preferably 0.1 mm or more and 1 mm or less, still more preferably 0.1 mm or more and 0.4 mm or less. be.

The fluid confluence condensing portion 20 is configured with a fluid confluence portion 21 in front of the pipe end of the small diameter pipe 11, and pores 22 are continuously perforated in the fluid confluence portion 21. Therefore, in the fluid merging portion 21, the first liquid flowing through the first flow path 11a and the second liquid flowing through the second flow path 12a merge immediately before the pores 22, and the fluid immediately after the merging remains as it is. It circulates in the pores 22.

As shown in FIG. 2A, the fluid merging portion 21 is preferably formed in a tapered cone shape converging toward the pores 22 from the viewpoint of suppressing aggregation of the polymer particle body in the merging fluid. The cone convergence angle θ ₁₁ is preferably 90 ° or more, more preferably 100 ° or more, and preferably 180 ° or less from the viewpoint of suppressing aggregation of the polymer particle body in the merged fluid. , More preferably 170 ° or less, still more preferably 140 ° or less. The cone convergence angle θ ₁₁ is preferably 90 ° or more and 180 ° or less, more preferably 100 ° or more and 170 ° or less, and further preferably 100 ° or more and 140 ° or less. The cone convergence angle θ ₁₁ is preferably the same as the cone expansion angle θ ₁₂ when the flow path expanding portion 31 has a cone shape, from the viewpoint of suppressing aggregation of the polymer particle body in the merged fluid.

The pipe end of the small-diameter pipe 11 of the fluid merging portion 21, that is, the length L1 from the end of the fluid flow path portion ₁₀ to the pores 22, is preferably from the viewpoint of suppressing aggregation of the polymer particle body in the merging fluid. It is 0.02 mm or more, more preferably 0.2 mm or more, still more preferably 0.3 mm or more, and from the same viewpoint, it is preferably 20 mm or less, more preferably 10 mm or less, still more preferably 1 mm or less. The length L ₁ is preferably 0.02 mm or more and 20 mm or less, more preferably 0.2 mm or more and 10 mm or less, and further preferably 0.3 mm or more and 1 mm or less.

The cross-sectional shape of the pores 22, the extending direction, the pore diameter d ₁ , the length l ₁ , and the ratio of the length l ₁ to the pore diameter d ₁ (length l ₁ / pore diameter d ₁ ), and the flow path area s ₁ have already been obtained. As mentioned above.

The fluid outflow portion 30 includes a flow path expanding portion 31 in front of the pores 22. The fluid flowing through the pores 22 flows out to the flow path expanding portion 31. The flow path expanding portion 31 communicates with the polymer dispersion liquid discharging portion 103 provided at the other end of the device.

The cross-sectional shape and shape of the flow path of the fluid outflow portion 30, the cone enlargement angle θ ₁₂ , and the maximum flow path diameter D ₁₄ of the flow path expansion portion 31 are as described above.

The micromixer 100 having the first configuration may be composed of a plurality of members each made of metal, ceramics, resin, or the like, and the fluid flow path portion 10 and the fluid merging contraction may be formed by combining these members. The flow portion 20 and the fluid outflow portion 30 may be configured.

In the micromixer 100 having the first configuration, the first liquid supply pipe 42a extending from the first liquid storage tank 41a is connected to the first liquid supply unit 101 communicating with the first flow path 11a. A first pump 43a for circulating the first liquid, a first flow meter 44a for detecting the flow rate of the first liquid, and a first filter 45a for removing impurities of the first liquid are upstream of the first liquid supply pipe 42a. A first pressure gauge 46a for detecting the pressure of the first liquid is attached to a portion between the first flow meter 44a and the first filter 45a, which are interposed in order from the side. Each of the first pump 43a, the first flow meter 44a, and the first pressure gauge 46a is electrically connected to the flow controller 47.

A second liquid supply pipe 42b extending from the second liquid storage tank 41b is connected to the second liquid supply unit 102 communicating with the second flow path 12a. A second pump 43b for flowing the second liquid, a second flow meter 44b for detecting the flow rate of the second liquid, and a second filter 45b for removing impurities of the second liquid are upstream in the second liquid supply pipe 42b. A second pressure gauge 46b for detecting the pressure of the second liquid is attached to a portion between the second flow meter 44b and the second filter 45b, which are interposed in order from the side. Each of the second pump 43b, the second flow meter 44b, and the second pressure gauge 46b is electrically connected to the flow controller 47. In this surface treatment system S, the pressure before the pore flow is the pressure measured by the second pressure gauge 46b, and the pressure after the pore flow is an open system, so it is 0. The pressure loss ΔP is a pressure value measured by the second pressure gauge 46b.

The flow rate controller 47 is configured to be able to input the set flow rate and the set pressure of the first liquid, and has a built-in arithmetic element. The set flow rate information of the first liquid and the flow rate detected by the first flow meter 44a. The operation of the first pump 43a is controlled based on the information and the pressure information detected by the first pressure gauge 46a. Similarly, the flow rate controller 47 is configured to be able to input the set flow rate and the set pressure of the second liquid, and the set flow rate information of the second liquid, the flow rate information detected by the second flow meter 44b, and the second pressure. The operation of the second pump 43b is controlled based on the pressure information detected by the total of 46b.

A polymer dispersion liquid recovery pipe 48 extends from the polymer dispersion liquid discharge unit 103 that communicates with the flow path expansion unit 31 and is connected to the polymer dispersion liquid recovery tank 49.

Next, the operation of this surface treatment system S will be described.

When the surface treatment system S is operated after the first liquid is charged in the first liquid storage tank 41a and the second liquid is charged in the second liquid storage tank 41b, the first pump 43a charges the first liquid in the first liquid storage tank. Continuing from the first liquid supply unit 101 of the fluid flow path portion 10 to the first flow path 11a of the small diameter tube 11 via the first liquid supply pipe 42a from 41a and passing through the first flow meter 44a and the first filter 45a in order. Supply. The first flow meter 44a sends the detected flow rate information of the first liquid to the flow controller 47. Further, the first pressure gauge 46a sends the detected pressure information of the first pressure gauge 46a to the flow rate controller 47.

The second pump 43b passes the second liquid from the second liquid storage tank 41b via the second liquid supply pipe 42b, and sequentially passes through the second flow meter 44b and the second filter 45b, and the second liquid of the fluid flow path portion 10. The supply unit 102 continuously supplies water to the second flow path 12a between the large-diameter pipe 12 and the small-diameter pipe 11. The second flow meter 44b sends the detected flow rate information of the second liquid to the flow controller 47. Further, the second pressure gauge 46b sends the detected pressure information of the second pressure gauge 46b to the flow rate controller 47.

The flow rate controller 47 of the first liquid is based on the set flow rate information and the set pressure information of the first liquid, the flow rate information detected by the first flow meter 44a, and the pressure information detected by the first pressure gauge 46a. The operation of the first pump 43a is controlled so that the set flow rate and the set pressure are maintained. At the same time, the flow rate controller 47 is based on the set flow rate information and the set pressure information of the second liquid, the flow rate information detected by the second flow meter 44b, and the pressure information detected by the second pressure meter 46b. The operation of the second pump 43b is controlled so that the set flow rate and the set pressure of the two liquids are maintained.

In the micromixer 100 having the first configuration, in the fluid flow path portion 10, the first liquid flows through the first flow path 11a and the second liquid flows through the second flow path 12a.

In the fluid merging and condensing section 20, the first and second liquids flowing out from the fluid flow path section 10 are the second liquid diagonally from the rear and from the entire circumference of the flowing first liquid in the fluid merging section 21. Meet in a colliding manner. In the fluid merging section 21, the fluid in which the first and second liquids have merged is mixed in the process of flowing through the pores 22. Then, in this process, in the merged fluid, a charged substance is adsorbed on the surface of the polymer particle body to form the polymer particle.

In the fluid outflow section 30, the fluid flowing through the pores 22 flows out in the flow path expanding section 31, and the polymer dispersion liquid in which the polymer particles adsorbed on the surface of the polymer particle body are dispersed in the dispersion medium is continuously operated. can get.

From the polymer dispersion liquid discharge unit 103 communicating with the flow path expansion unit 31, the obtained polymer dispersion liquid is collected in the polymer dispersion liquid recovery tank 49 via the polymer dispersion liquid recovery pipe 48.

FIGS. 3A to 3C show the micromixer 100 having the second configuration. The part having the same name as the first configuration is indicated by the same reference numeral as the first configuration.

The micromixer 100 having the second configuration includes a fluid flow path portion 10, a fluid confluence confluence section 20 continuously provided on the downstream side thereof, and a fluid outflow section 30 continuously provided on the downstream side thereof. And.

The fluid flow path portion 10 has one small diameter pipe 11 and a large diameter pipe 12. The large-diameter pipe 12 accommodates the small-diameter pipe 11, which have a common length direction and are arranged coaxially. As a result, the fluid flow path portion 10 is configured with the first flow path 11a inside the small diameter pipe 11 and the second flow path 12a inside the large diameter pipe 12 and outside the small diameter pipe 11. The tube end surface of the small diameter tube 11 is formed on a surface perpendicular to the axial direction. The first flow path 11a in the small diameter tube 11 communicates with the first liquid supply unit 101, and the second flow path 12a in the large diameter tube 12 communicates with the second liquid supply unit 102. As a result, the first liquid flows through the first flow path 11a, and the second liquid flows through the second flow path 12a. The micromixer 100 having a second configuration in which the fluid flow path portion 10 has a simple double pipe structure is easy to maintain by disassembling and cleaning.

The fluid confluence condensing portion 20 has a pipe structure continuous with the large-diameter pipe 12, and its front end is sealed by a wall perpendicular to the axial direction, and a pore 22 is perforated in the center of the wall. As a result, the fluid merging and condensing portion 20 is configured with the fluid merging portion 21 in the cylindrical space in front of the pipe end of the small diameter pipe 11. The length of the fluid confluence portion 21, that is, the length L ₂ from the end of the fluid flow path portion 10 to the pores 22, is preferably 0.1 mm or more from the viewpoint of suppressing aggregation of the polymer particle body in the confluent fluid. , More preferably 0.2 mm or more, still more preferably 0.5 mm or more, and from the same viewpoint, preferably 3.0 mm or less, more preferably 2.0 mm or less, still more preferably 1.5 mm or less. .. The length L ₂ is preferably 0.1 mm or more and 3.0 mm or less, more preferably 0.2 mm or more and 2.0 mm or less, and further preferably 0.5 mm or more and 1.5 mm or less.

In the fluid merging section 21, the first liquid flowing through the first flow path 11a and the second liquid flowing through the second flow path 12a merge, and in the pores 22, the first and second liquids in the fluid merging section 21 merge. The fluid that merged with each other circulates.

The fluid outflow portion 30 includes a flow path expanding portion 31 in a cylindrical space in front of the pores 22. The fluid flowing through the pores 22 flows out to the flow path expanding portion 31. The flow path expanding portion 31 communicates with the polymer dispersion liquid discharging portion 103.

Other configurations and operations are the same as in the case of the micromixer 100 having the first configuration.

By the way, the first and second liquids flowing out of the fluid flow path portion 10 and merging at the fluid merging portion 21 are finally mixed by the pores 22. At this time, in order to obtain higher speed mixing performance, it is sufficient that the mixed state of the fluid merging portion 21 is composed of minute segments of each liquid. Therefore, it is preferable that the number of the first flow paths 11a is larger, and there are a plurality of small diameter tubes 11 as shown in FIGS. 4A and 4B than when there is one small diameter tube 11 as shown in FIGS. 3A and 3B. In the case of, a faster mixing characteristic can be obtained.

FIG. 5 shows a micromixer 100 having a third configuration. The part having the same name as the first configuration is indicated by the same reference numeral as the first configuration.

The micromixer 100 having the third configuration is composed of a T-shaped tube including a straight tube portion 110 and a branch tube portion 120 branched from the central portion of the straight tube portion 110 and extending in an orthogonal direction. Such a T-shaped tube micromixer 100 has a simple device configuration and is easy to maintain by disassembling and cleaning.

One end of the straight tube portion 110 is for the first liquid supply section 101, the other end of the straight tube portion 110 is for the second liquid supply section 102, and the end of the branch tube portion 120 is for the polymer dispersion liquid discharge section. It is configured in 103 respectively.

The straight pipe portion 110 is composed of a large pore diameter portion on both sides, while the central portion is configured in a small pore diameter portion in which the flow path is discontinuously narrowed from the large pore diameter portion, of which one end side is the first flow. The path 11a and the other end side are configured in the second flow path 12a, respectively.

The branch pipe portion 120 has pores 22 extending along the pipe axis and communicating with the straight pipe portion 110, and the central portion of the straight pipe portion 110, that is, the inside of the branch portion to the branch pipe portion 120. Is configured in the fluid confluence 21 continuous with the pores 22. The branch pipe portion 120 is configured with a flow path expanding portion 31 in a cylindrical space in which the flow path is discontinuously expanded following the pores 22.

The inner diameters D ₃₁ , D ₃₂ , and D ₃₄ of the large hole diameter portions on both sides of the straight pipe portion 110 and the flow path expansion portion 31 of the branch pipe portion are preferably 0 from the viewpoint of suppressing aggregation of the polymer particle body in the merged fluid. It is 0.3 mm or more, more preferably 0.5 mm or more, and from the same viewpoint, it is preferably 5.0 mm or less, more preferably 3.0 mm or less, still more preferably 1.0 mm or less. The inner diameters D ₃₁ , D ₃₂ , and D ₃₄ are preferably 0.3 mm or more and 5.0 mm or less, more preferably 0.5 mm or more and 3.0 mm or less, and further preferably 0.5 mm or more and 1.0 mm or less. Each of the first flow path 11a and the second flow path 12a has an inner diameter D ₃₃ and a flow path cross-sectional area, that is, a pore area equal to or similar to that of the pore 22. Therefore, in the micromixer 100 having the third configuration, the first and second liquids before merging are circulated to the first flow path 11a and the second flow path 12a constituting the pores and merged, and subsequently. , A polymer dispersion is produced by further circulating the fluid in which they are merged into the pores 22. From the viewpoint of keeping the pressure loss ΔP small, it is preferable that the lengths of the first flow path 11a and the second flow path 12a, that is, the hole lengths are the same as or about the same as the pores 22.

The configuration such as the shape and size of the pores 22 and the operation in the production of the polymer particles are the same as in the case of the micromixer 100 having the first configuration.

By the way, in the micromixer 100 having the third configuration shown in FIG. 5, the flow directions of the first and second liquids toward the fluid confluence 21 and the extending directions of the pores 22 are different from each other. The present invention is not particularly limited to this, and for example, as shown in FIG. 6, one end of the straight tube portion 110 is the first liquid supply section 101, and the end of the branch tube portion 120 is the second liquid supply section. Further, the other end of the straight tube portion 110 is configured in the polymer dispersion liquid discharge portion 103, and one of the respective flow directions toward the fluid confluence portion 21 of the first and second liquids is the pore 22. The configuration may be the same as the extending direction of. However, from the viewpoint of suppressing the aggregation of the polymer particle body in the merging fluid, the respective flows toward the fluid merging portion 21 of the first and second liquids as in the micromixer 100 having the third configuration shown in FIG. It is preferable that the direction and the extending direction of the pores 22 are different from each other.

Further, the micromixer 100 having the third configuration shown in FIG. 5 has a configuration having a first flow path 11a and a second flow path 12a in which the flow path in the central portion of the straight tube portion 110 is narrowed. For example, as shown in FIG. 7, a uniform flow path may be formed in the straight tube portion 110 from one end to the other end. In the micromixer 100 shown in FIG. 7, neither the first liquid nor the second liquid before merging is circulated in the pores, and only the fluid in which they are merged is circulated in the pores 22, so that the polymer dispersion liquid is circulated. To manufacture.

Further, in the micromixer 100 having the third configuration shown in FIG. 5, the straight tube portion 110 and the branch tube portion 120 are communicated with each other via the pores 22, but the present invention is not particularly limited to this. For example, as shown in FIG. 8, the main body portion is composed of a T-shaped pipe having a straight pipe portion 110 and a branch pipe portion 120 having a uniform flow path, and the end opening of the branch pipe portion 120 is closed. A plate-shaped member 130 having pores 22 formed in the center may be provided. Even in the micromixer 100 shown in FIG. 8, neither the first liquid nor the second liquid before merging is circulated in the pores, and only the fluid in which they are merged is circulated in the pores 22, so that the polymer dispersion liquid is circulated. To manufacture.

FIG. 9 shows a micromixer 100 having a fourth configuration. The part having the same name as the first configuration is indicated by the same reference numeral as the first configuration.

The micromixer 100 having the fourth configuration is composed of a Y-shaped tube in which three first to third tubes 111 to 113 are butted and connected to communicate with each other. Such a Y-tube micromixer 100 has a simple device configuration and is easy to maintain by disassembling and cleaning.

The end of the first pipe 111 is to the first liquid supply part 101, the end of the second pipe 112 is to the second liquid supply part 102, and the end of the third pipe 113 is the polymer dispersion liquid discharge part. It is configured in 103 respectively.

Each of the first to third pipes 111 to 113 has a large hole diameter portion on the end side, while the coupling end side is configured on a small hole diameter portion in which the flow path is discontinuously narrowed from the large hole diameter portion. The first pipe 111 has a first flow path 11a, the second pipe 112 has a second flow path 12a, and the third pipe 113 has a pore 22. The small hole diameter portion of the first pipe 111 constituting the first flow path 11a, the small hole diameter portion of the second pipe 112 constituting the second flow path 12a, and the coupling portion of the pores 22 are configured in the fluid confluence portion 21. Has been done. The third tube 113 is configured with a flow path expanding portion 31 in a cylindrical space in which the flow path is discontinuously expanded following the pores 22.

Each of the large hole diameter portions of the first to third pipes 111 to 113 and the inner diameters D ₄₁ , D ₄₂ , and D ₄₅ of the flow path expanding portion 31 is preferable from the viewpoint of suppressing aggregation of the polymer particle body in the merged fluid. It is 0.5 mm or more, more preferably 1.0 mm or more, and from the same viewpoint, it is preferably 5.0 mm or less, more preferably 3.0 mm or less, still more preferably 1.2 mm or less. Each of the inner diameters D ₄₁ , D ₄₂ , and D ₄₅ is preferably 0.5 mm or more and 5.0 mm or less, more preferably 1.0 mm or more and 3.0 mm or less, and further preferably 1.0 mm or more and 1.2 mm or less. Further, from the viewpoint of suppressing the aggregation of the polymer particle body in the merged fluid, it is preferable that D ₄₁ , D ₄₂ and D ₄₅ are the same. Further, each of the first flow path 11a and the second flow path 12a has an inner diameters D ₄₃ and D ₄₄ , a flow path cross-sectional area, that is, a pore area equal to or similar to that of the pore 22. Therefore, in the micromixer 100 having the fourth configuration, the first and second liquids before merging are circulated to the first flow path 11a and the second flow path 12a constituting the pores, respectively, and merged with each other. Then, the fluid in which they are merged is circulated in the pores 22 to produce a polymer dispersion. From the viewpoint of keeping the pressure loss ΔP small, it is preferable that the lengths L ₄₃ and L ₄₄ of the first flow path 11a and the second flow path 12a, that is, the hole length is the same as or about the same as that of the pore 22.

The angle Θ ₄₁ formed by the extending direction of the first flow path 11a and the extending direction of the pore 22 and the angle Θ ₄₂ formed by the extending direction of the second flow path 12a and the extending direction of the pore 22 are each of the merged fluids. It is preferably more than 90 °, more preferably 100 ° or more, still more preferably 120 ° or more, still more preferably 140 ° or more, and preferably from the same viewpoint, from the viewpoint of suppressing the aggregation of the polymer particle body in the above. Is less than 180 °, more preferably 170 ° or less, still more preferably 160 ° or less. Each of the angle Θ ₄₁ and the angle Θ ₄₂ is preferably larger than 90 ° and less than 180 °, more preferably 100 ° or more and 170 ° or less, still more preferably 120 ° or more and 160 ° or less, still more preferably 140 ° or more. It is 160 ° or less. Further, from the viewpoint of suppressing the aggregation of the polymer particle body in the merged fluid, it is preferable that Θ ₄₁ = Θ ₄₂ . The angle Θ ₄₃ formed by the first flow path 11a and the second flow path 12a preferably exceeds 0 °, more preferably 20 ° or more, still more preferably 20 ° or more, from the viewpoint of suppressing aggregation of the polymer particle body in the merged fluid. Is 40 ° or more, and from the same viewpoint, preferably less than 180 °, more preferably 160 ° or less, still more preferably 120 ° or less, still more preferably 80 ° or less. The angle Θ ₄₃ is preferably greater than 0 ° and less than 180 °, more preferably 20 ° or more and 160 ° or less, still more preferably 40 ° or more and 120 ° or less, still more preferably 40 ° or more and 80 ° or less.

The configuration such as the shape and size of the pores 22 and the operation in the production of the polymer particles are the same as in the case of the micromixer 100 having the first configuration.

<Polymer dispersion>
According to the method for producing polymer particles according to the embodiment, after this surface treatment step, a polymer dispersion liquid in which polymer particles in which a charged substance is adsorbed on the surface of a polymer particle body is dispersed in a dispersion medium can be obtained.

The Z average particle size of the polymer particles contained in the obtained polymer dispersion is preferably 0.01 μm or more, more preferably 0.05 μm or more, still more preferably 0.1 μm or more, and preferably 10 μm or less. It is more preferably 5 μm or less, still more preferably 2.5 μm or less. The Z average particle size of the polymer particles is preferably 0.01 μm or more and 10 μm or less, more preferably 0.05 μm or more and 5 μm or less, and further preferably 0.1 μm or more and 2.5 μm or less.

Particle body of polymer particles contained in the obtained polymer dispersion The ratio of Z average particle size to the polymer particle body before adsorption contained in the dispersion (Z average particle size of polymer particles / Z average particle size of polymer particle body) ) Is the degree of aggregation, the degree of aggregation is 1 or more, preferably 10 or less, more preferably 7.5 or less, and further preferably 5.0 or less.

The zeta potential of the polymer particles contained in the obtained polymer dispersion is greater than zero for the cationic polymer particles in which the cationic group-containing substance of the charged substance is adsorbed on the surface of the anionic polymer particle body, while the cationic polymer. It is smaller than zero for anionic polymer particles in which an anionic group-containing substance of a charged substance is adsorbed on the surface of the particle body. The absolute value of the zeta potential of the polymer particles is preferably 0.1 mV or more, more preferably 1 mV or more, still more preferably 5 mV or more, and preferably 50 mV or less, more preferably 30 mV or less, still more preferably 25 mV or less. be. The absolute value of the zeta potential of the polymer particles is preferably 0.1 mV or more and 50 mV or less, more preferably 1 mV or more and 30 mV or less, and further preferably 5 mV or more and 25 mV or less.

If the difference obtained by subtracting the zeta potential of the polymer particle body before adsorption contained in the particle body dispersion from the zeta potential of the polymer particles contained in the obtained polymer dispersion is taken as the charge conversion degree, the absolute charge conversion degree is absolute. The value is preferably 1 mV or more, more preferably 10 mV or more, still more preferably 20 mV or more, and preferably 100 mV or less, more preferably 80 mV or less, still more preferably 60 mV or less. The absolute value of the charge conversion degree is preferably 1 mV or more and 100 mV or less, more preferably 10 mV or more and 80 mV or less, and further preferably 20 mV or more and 60 mV or less.

The polymer dispersion liquid containing the polymer particles obtained as described above can be used as, for example, a composition for washing clothes such as detergents, sizing agents, softeners and bleaches, adhesives, adhesives, paints, coating agents and the like. Used as a compounding agent.

Hereinafter, experiments for producing polymer particles of Examples 1 to 4 and Comparative Examples 1-1 to 2 will be described. The respective configurations are also shown in Tables 1 and 2.

(Surface treatment system)
In the surface treatments of Examples 1 to 4, the same surface treatment system A as shown in FIG. 1 in the above embodiment to which the micromixer 100 of the first configuration shown in FIGS. 2A and 2B was applied was used.

The micromixer 100 having the first configuration has an outer diameter D ₁₁ : 3 mm of the small diameter tube 11, an inner diameter D ₁₂ : 2 mm of the small diameter tube 11, an inner diameter D ₁₃ : 4.71 mm of the large diameter tube 12, and a small diameter tube 11 and a large diameter. Gap between the tube 12 Δ ₁ : 0.855 mm, gap between the small diameter tube 11 and the large diameter tube δ ₁ : 0.25 mm, length from the end of the fluid flow path portion 10 to the pore 22 L ₁ : 0. 68 mm, cone convergence angle of fluid confluence 21 θ ₁₁ : 120 °, pore diameter d ₁ : 0.22 mm, pore length l ₁ : 0.55 mm, flow path area of pore 22 s ₁ : 0.038 mm ² , the length of the pore 22 l ₁ / the pore diameter of the pore 22 d ₁ : 2.5, the cone expansion angle of the flow path expansion section 31 θ ₁₂ : 120 °, the maximum flow of the flow path expansion section 31 The one having a path diameter D ₁₄ : 2 mm and a maximum flow path diameter D ₁₄ / pore diameter 22 pore diameter d ₁ : 9.1 was used.

(Particle body dispersion)
N-butyl acrylate (hereinafter referred to as "BA"), methyl methacrylate (hereinafter referred to as "MMA"), and methacrylic acid in the same manner as disclosed in JP-A-2015-117315. By emulsifying and polymerizing 2-hydroxyethyl (hereinafter referred to as "HEMA") and acrylic acid (hereinafter referred to as "AA"), BA: MMA: HEMA: AA = 63: 31: 5: 1. A particle body dispersion liquid 1-1 having a solid content concentration c1 in which the polymer particle body ₁ copolymerized at the molar ratio of 30% by mass was dispersed in water was prepared. Further, in a separate lot from the particle body dispersion liquid 1-1, a particle body dispersion liquid 1-2 having a solid content concentration c ₁ in which the polymer particle body 1 was dispersed in water was similarly prepared. No surfactant was used in the preparation of the particle body dispersions 1-1 and 1-2.

A polymer copolymerized at a molar ratio of BA: MMA: AA = 72: 27: 1 by emulsion polymerization of BA, MMA, and AA in the same manner as disclosed in JP-A-2015-117315. A particle body dispersion liquid 2-1 having a solid content concentration c ₁ in which the particle body 2 was dispersed in water was prepared. In addition to the particle body dispersion liquid 2-1, similarly, the particle body dispersion liquid 2-2 and the particle body dispersion liquid 2-3 having a solid content concentration c1 in which the polymer particle body ₂ is dispersed in water are 30% by mass. Prepared. An anionic surfactant (polyoxyethylene lauryl ether sodium sulfate, manufactured by Emar 20C Kao Corporation) was used in the preparation of the particle body dispersion liquid 2-1. No surfactant was used in the preparation of the particle body dispersion 2-2. In the preparation of the particle body dispersion liquid 2-3, a nonionic surfactant (ethylene oxide adduct of lauryl alcohol, manufactured by Emargen 150 Kao Corporation) was used.

By emulsion polymerization of vinyl acetate (hereinafter referred to as "Vac") and methacrylic acid (hereinafter referred to as "MAA") in the same manner as disclosed in JP-A-2015-117315. A particle body dispersion liquid 3 having a solid content concentration c ₁ in which the polymer particle body 3 copolymerized at a molar ratio of Vac: MAA = 97: 3 was dispersed in water was prepared. An anionic surfactant (polyoxyethylene lauryl ether sodium sulfate, manufactured by Emar 20C Kao Corporation) was used in the preparation of the particle body dispersion liquid 3.

The particle body dispersion liquids 1-1 to 3 have reduced residual monomers by distillation in the same manner as disclosed in JP-A-2015-117315 after emulsion polymerization.

A cationic particle body dispersion liquid (manufactured by Viniblanc 2687 Nisshin Kagaku Co., Ltd.) having _a solid content concentration c1 in which the acrylic polymer particle body 4 exhibiting cationic properties was dispersed in water was used as the particle body dispersion liquid 4. ..

(Liquid containing charged substances)
A charged substance-containing liquid 1 having a solid content concentration c2 of ₅ % by mass contained in water as a charged substance 1 containing cationized starch (MX2075 Kao Corporation, weight average molecular weight (Mw): 13.6 million) which is a cationic group-containing substance. Was prepared.

A charged substance having a solid content concentration c2 of 5% by mass, which is contained in water as a charged substance ₂ containing a cationized starch (manufactured by Excell DH Nissho Chemical Co., Ltd., weight average molecular weight (Mw): 3.57 million) which is a cationic group-containing substance. The containing liquid 2 was prepared.

A charged substance-containing liquid 3 having a solid content concentration c ₂ contained in water of 5% by mass was prepared by using stearyltrimethylammonium chloride (Q86W, manufactured by Kao Co., Ltd.), which is a quaternary ammonium salt which is a cationic group-containing substance, as a charged substance 3.

Cationized Poval (CM-318, manufactured by Kuraray Co., Ltd., weight average molecular weight (Mw): 80,000), which is a cationic group-containing substance, is contained in water as a charged substance 4 and contains a charged substance having a solid content concentration c ₂ of 5% by mass. Liquid 4 was prepared.

Prepare a charged substance-containing liquid 5 having a solid content concentration c ₂ of 3.5% by mass, which is contained in water as a charged substance 5 using sodium polyacrylate (weight average molecular weight (Mw): 10,000) which is an anionic group-containing substance. did. The sodium polyacrylate was produced by performing the same operation as in Example 3 described in paragraphs 0069 to 0071 of JP-A-2010-150327.

(Test method)
<Z average particle size and zeta potential>
The Z average particle diameter of the polymer particle body was measured by a dynamic light scattering method for each of the particle body dispersions 1-1 to 4. In addition, the Z average particle size of the polymer particles was measured in the same manner for each of the polymer dispersions obtained in Examples 1 to 4 and Comparative Examples 1-1 to 2. Then, the ratio of the Z average particle diameter of the polymer particles to the polymer particle body was calculated as the degree of cohesion.

The zeta potential of the polymer particle body was measured by light scattering electrophoresis for each of the particle body dispersions 1-1 and 2-1 to 4. In addition, the zeta potentials of the polymer particles were measured in the same manner for each of the polymer dispersions obtained in Examples 1 to 4 and Comparative Example 2. Then, the difference obtained by subtracting the zeta potential of the polymer particle body from the zeta potential of the polymer particle was calculated as the charge conversion degree.

For the Z average particle size and zeta potential, specifically, a sample of the particle body dispersion or the polymer dispersion is diluted 1000 times with tap water (carbonate alkalinity: 37 degrees (mg / lCaCO ₃ )) and Malvern. The measurement was performed using a Zetasizer Nano ZS (Nano-ZS) manufactured by the same company. In the measurement, for water as a dispersion medium, the temperature was set to 25 ° C., the viscosity was set to 0.8872 cP, the RI (refractive index) was set to 1.330, and the dielectric constant was set to 78.5.

The carbonate alkalinity was determined by the following method. First, 100 ml of test water was placed in a 200 ml beaker, and 0.15 ml of a bromocresol green-methyl red ethanol solution (manufactured by Wako Pure Chemical Industries, Ltd.) was added as an indicator. The solution was titrated with 10 mmol / l sulfuric acid while stirring with a magnetic stirrer and a rotor (length 30 mm, diameter 8 mm) (rotation number 200 rpm) until the color of the solution changed from blue to purplish red. Then, the carbonate alkalinity was calculated based on the following equation.
Carbonate alkalinity (degrees) = a × 10
(A is the amount (ml) of 10 mmol / l sulfuric acid required for titration. In the above formula, once means 1 CaCO ₃ mg / l).

<Appearance of polymer dispersion>
The appearance of each of the polymer dispersions obtained in Examples 1 to 4 and Comparative Examples 1-1 to 2 was visually confirmed immediately after production and after storage for 24 hours. Then, the case where the dispersion was uniform was evaluated as A, the case where partial precipitation occurred and a non-uniform part was present was evaluated as B, and the case where significant precipitation occurred and clear separation could be confirmed was evaluated as C.

(Manufacturing of polymer particles)
<Example 1>
As the first liquid, the particle body dispersion liquid 1-1 was charged into the first liquid storage tank 41a of FIG. 1 and brought to room temperature (20 ° C.). Further, as the second liquid, the charged substance-containing liquid 1 was charged into the second liquid storage tank 41b of FIG. 1 and brought to room temperature (20 ° C.).

The surface treatment system A is operated, and at room temperature (20 ° C.), the molar ratio of the cationic group of the charged substance 1 in the charged substance-containing liquid 1 to the anionic group of the polymer particle body 1 in the particle body dispersion liquid 1-1. The flow rate _Q1 of the particle body dispersion liquid 1-1 is 8.4 L / h and the flow rate _Q2 of the charged substance-containing liquid 1 is 10.6 L / h so that the (cationic group / anionic group) is 0.45. By setting them as h and mixing them with the micromixer 100 in a continuous operation, a polymer dispersion liquid in which the polymer particles in which the charged substance 1 is adsorbed on the surface of the polymer particle body 1 is dispersed in water is obtained in the polymer dispersion liquid recovery tank 49. rice field.

At this time, the flow rate ratio (Q ₁ / Q ₂ ) of the particle body dispersion liquid 1-1 to the charged substance-containing liquid 1 was 0.8. The ratio of the content m ₂ of the charged substance 1 to the content m ₁ of the polymer particle body 1 in the fluid flowing through the pores 22 was 14.7% by mass. The flow rate Q of the fluid flowing through the pores 22 was 19.0 L / h. The flow velocity u of the fluid flowing through the pores was 14.5 m / s. The Reynolds number Re of the fluid flowing through the pores was 83571. The pressure loss ΔP before and after the pores was 0.2 MPa.

<Comparative Example 1-1>
At room temperature (20 ° C.), the molar ratio of the cationic group of the charged substance 1 in the charged substance-containing liquid 1 to the anionic group of the polymer particle body 1 in the particle body dispersion liquid 1-2 (cationic group / anionic group). ) Is 0.28, the particle body dispersion liquid 1-2 is dropped onto the charged substance-containing liquid 1, and the particles are stirred and mixed by a batch operation to bring the charged substance 1 onto the surface of the polymer particle body 1. A polymer dispersion was obtained in which the polymer particles adsorbed by the particles were dispersed in water. The ratio of the content m ₂ of the charged substance 1 to the content m ₁ of the polymer particle body 1 was 9.0% by mass.

<Comparative Example 1-2>
The molar ratio (cationic group / anionic group) of the cationic group of the charged substance 1 in the charged substance-containing liquid 1 to the anionic group of the polymer particle body 1 in the particle body dispersion liquid 1-2 is 0.46. By performing the same operation as in Comparative Example 1-1 except for the above, a polymer dispersion liquid in which the polymer particles in which the charged substance 1 was adsorbed on the surface of the polymer particle body 1 was dispersed in water was obtained. The ratio of the content m ₂ of the charged substance 1 to the content m ₁ of the polymer particle body 1 was 14.9% by mass.

<Comparative Example 1-3>
At room temperature (20 ° C.), the molar ratio (cationic group / anionic group) of the cationic group of the charged substance 1 to the anionic group of the polymer particle body 1 in the particle body dispersion liquid 1-2 is 0.28. As described above, cationized starch (manufactured by MX2075 Kao Co., Ltd.), which is a cationic group-containing substance, is added to the particle body dispersion liquid 1-2 and dissolved by heating, and these are stirred and mixed by a batch operation. A polymer dispersion was obtained in which the polymer particles in which the charged substance 1 was adsorbed on the surface of the polymer particle body 1 were dispersed in water. The ratio of the content m ₂ of the charged substance 1 to the content m ₁ of the polymer particle body 1 was 9.0% by mass.

<Comparative Example 1-4>
Except that the molar ratio (cationic group / anionic group) of the cationic group of the charged substance 1 to the anionic group of the polymer particle body 1 in the particle body dispersion liquid 1-2 is 0.46. By performing the same operation as in Comparative Example 1-3, a polymer dispersion liquid in which the polymer particles in which the charged substance 1 was adsorbed on the surface of the polymer particle body 1 was dispersed in water was obtained. The ratio of the content m ₂ of the charged substance 1 to the content m ₁ of the polymer particle body 1 was 14.9% by mass.

<Example 2-1>
As the first liquid, the particle body dispersion liquid 2-1 was charged in the first liquid storage tank 41a and brought to room temperature (20 ° C.). Further, as the second liquid, the charged substance-containing liquid 2 was charged into the second liquid storage tank 41b and brought to room temperature (20 ° C.).

The surface treatment system A is operated, and at room temperature (20 ° C.), the molar ratio of the cationic group of the charged substance 2 in the charged substance-containing liquid 2 to the anionic group of the polymer particle body 2 in the particle body dispersion liquid 2-1. The flow rate _Q1 of the particle body dispersion liquid 2-1 is 1.6 L / h and the flow rate Q2 of the charged substance-containing liquid ₂ is 1.4 L / h so that the (cationic group / anionic group) is 0.31. By setting them as h and mixing them with the micromixer 100 in a continuous operation, a polymer dispersion liquid in which the polymer particles in which the charged substance 2 is adsorbed on the surface of the polymer particle body 2 is dispersed in water is obtained in the polymer dispersion liquid recovery tank 49. rice field.

At this time, the flow rate ratio (Q ₁ / Q ₂ ) of the particle body dispersion liquid 2-1 to the charged substance-containing liquid 2 was 1.2. The ratio of the content m ₂ of the charged substance 2 to the content m ₁ of the polymer particle body 2 in the fluid flowing through the pores 22 was 9.9% by mass. The flow rate Q of the fluid flowing through the pores 22 was 3.0 L / h. The flow velocity u of the fluid flowing through the pores was 21.8 m / s. The pressure loss ΔP before and after the pores was 0.6 MPa.

<Example 2-2>
The molar ratio (cationic group / anionic group) of the cationic group of the charged substance 2 in the charged substance-containing liquid 2 to the anionic group of the polymer particle body 2 in the particle body dispersion liquid 2-1 is 0.46. As described above, the same as in Example 2-1 except that the flow rate _Q1 of the particle body dispersion liquid 2-1 was 1.3 L / h and the flow rate Q2 of the charged substance-containing liquid ₂ was 1.7 L / h. By performing the operation, a polymer dispersion liquid in which the polymer particles in which the charged substance 2 was adsorbed on the surface of the polymer particle body 2 was dispersed in water was obtained in the polymer dispersion liquid recovery tank 49.

At this time, the flow rate ratio (Q ₁ / Q ₂ ) of the particle body dispersion liquid 2-1 to the charged substance-containing liquid 2 was 0.8. The ratio of the content m ₂ of the charged substance 2 to the content m ₁ of the polymer particle body 2 in the fluid flowing through the pores 22 was 14.8% by mass. The flow rate Q of the fluid flowing through the pores 22 was 3.0 L / h. The flow velocity u of the fluid flowing through the pores was 21.9 m / s. The pressure loss ΔP before and after the pores was 0.6 MPa.

<Example 2-3>
As the first liquid, the particle body dispersion liquid 2-2 was charged into the first liquid storage tank 41a and brought to room temperature (20 ° C.). Further, as the second liquid, the charged substance-containing liquid 3 was charged into the second liquid storage tank 41b and brought to room temperature (20 ° C.).

The surface treatment system A is operated, and at room temperature (20 ° C.), the molar ratio of the cationic group of the charged substance 3 in the charged substance-containing liquid 3 to the anionic group of the polymer particle body 2 in the particle body dispersion liquid 2-2. The flow rate _Q1 of the particle body dispersion liquid 2-2 is 10.8 L / h and the flow rate _Q2 of the charged substance-containing liquid 3 is 9.6 L / h so that the (cationic group / anionic group) is 2.1. By setting them as h and mixing them with the micromixer 100 in a continuous operation, a polymer dispersion liquid in which the polymer particles in which the charged substance 3 is adsorbed on the surface of the polymer particle body 2 is dispersed in water is obtained in the polymer dispersion liquid recovery tank 49. rice field.

At this time, the flow rate ratio (Q ₁ / Q ₂ ) of the particle body dispersion liquid 2-2 to the charged substance-containing liquid 3 was 1.1. The ratio of the content m ₂ of the charged substance 3 to the content m ₁ of the polymer particle body 2 in the fluid flowing through the pores 22 was 10.3% by mass. The flow rate Q of the fluid flowing through the pores 22 was 20.4 L / h. The flow velocity u of the fluid flowing through the pores was 15.6 m / s. The pressure loss ΔP before and after the pores was 0.3 MPa.

<Example 2-4>
As the first liquid, the particle body dispersion liquid 2-3 was charged into the first liquid storage tank 41a and brought to room temperature (20 ° C.). Further, as the second liquid, the charged substance-containing liquid 4 was charged into the second liquid storage tank 41b and brought to room temperature (20 ° C.).

The surface treatment system A is operated, and at room temperature (20 ° C.), the molar ratio of the cationic group of the charged substance in the charged substance-containing liquid 4 to the anionic group of the polymer particle body 2 in the particle body dispersion liquid 2-3 ( The flow rate _Q1 of the particle body dispersion liquid _2-3 is 1.6 L / h and the flow rate Q2 of the charged substance-containing liquid 4 is 1.4 L / h so that the (cationic group / anionic group) is 0.25. By continuously mixing them with the micromixer 100, a polymer dispersion in which the polymer particles in which the charged substance 4 was adsorbed on the surface of the polymer particle body 2 was dispersed in water was obtained in the polymer dispersion recovery tank 49. ..

At this time, the flow rate ratio (Q ₁ / Q ₂ ) of the particle body dispersion liquid 2-3 to the charged substance-containing liquid 4 was 1.1. The ratio of the content m ₂ of the charged substance 4 to the content m ₁ of the polymer particle body 2 in the fluid flowing through the pores 22 was 10.4% by mass. The flow rate Q of the fluid flowing through the pores 22 was 2.9 L / h. The flow velocity u of the fluid flowing through the pores was 11.5 m / s. The pressure loss ΔP before and after the pores was 0.5 MPa.

<Comparative Example 2>
At room temperature (20 ° C.), the molar ratio of the cationic group of the charged substance 2 in the charged substance-containing liquid 2 to the anionic group of the polymer particle body 2 in the particle body dispersion liquid 2-1 (cationic group / anionic group). ) Is 0.30, the particle body dispersion liquid 2-1 is dropped onto the charged substance-containing liquid 2, and the particles are stirred and mixed by a batch operation to bring the charged substance 2 onto the surface of the polymer particle body 2. A polymer dispersion was obtained in which the polymer particles adsorbed by the particles were dispersed in water. The ratio of the content m ₂ of the charged substance 2 to the content m ₁ of the polymer particle body 2 was 9.7% by mass.

<Example 3>
The particle body dispersion liquid 3 was charged into the first liquid storage tank 41a as the first liquid and brought to room temperature (20 ° C.). Further, as the second liquid, the charged substance-containing liquid 2 was charged into the second liquid storage tank 41b and brought to room temperature (20 ° C.).

The surface treatment system A is operated, and at room temperature (20 ° C.), the molar ratio of the cationic group of the charged substance 2 in the charged substance-containing liquid 2 to the anionic group of the polymer particle body 3 in the particle body dispersion liquid 3 (cation). The flow rate _Q1 of the particle body dispersion liquid 3 is 1.3 L / h and the flow rate Q2 of the charged substance-containing liquid ₂ is 1.7 L / h so that the sex group / anionic group) is 0.13. Was continuously mixed by the micromixer 100 to obtain a polymer dispersion in which the polymer particles in which the charged substance 2 was adsorbed on the surface of the polymer particle body 3 were dispersed in water in the polymer dispersion recovery tank 49.

At this time, the flow rate ratio (Q ₁ / Q ₂ ) of the particle body dispersion liquid 3 to the charged substance-containing liquid 2 was 0.7. The ratio of the content m ₂ of the charged substance 2 to the content m ₁ of the polymer particle body 3 in the fluid flowing through the pores 22 was 12.5% by mass. The flow rate Q of the fluid flowing through the pores 22 was 3.0 L / h. The flow velocity u of the fluid flowing through the pores was 21.9 m / s. The pressure loss ΔP before and after the pores was 0.4 MPa.

<Example 4>
The particle body dispersion liquid 4 was charged into the first liquid storage tank 41a as the first liquid and brought to room temperature (20 ° C.). Further, as the second liquid, the charged substance-containing liquid 5 was charged into the second liquid storage tank 41b and brought to room temperature (20 ° C.).

The surface treatment system A is operated, and at room temperature (20 ° C.), the flow rate _Q1 of the particle body dispersion liquid 4 is set to _1.2 L / h and the flow rate Q2 of the charged substance-containing liquid 5 is set to 1.2 L / h. By mixing with the micromixer 100 in a continuous operation, a polymer dispersion liquid in which the polymer particles in which the charged substance 5 was adsorbed on the surface of the polymer particle body 4 was dispersed in water was obtained in the polymer dispersion liquid recovery tank 49.

At this time, the flow rate ratio (Q ₁ / Q ₂ ) of the particle body dispersion liquid 4 to the charged substance-containing liquid 5 was 1.0. The ratio of the content m ₂ of the charged substance 5 to the content m ₁ of the polymer particle body 4 in the fluid flowing through the pores 22 was 10.9% by mass. The flow rate Q of the fluid flowing through the pores 22 was 2.4 L / h. The flow velocity u of the fluid flowing through the pores was 5.4 m / s. The pressure loss ΔP before and after the pores was 0.1 MPa.

From the above results, it can be seen that in Examples 1 to 4, a polymer dispersion liquid in which polymer particles having a small particle size are dispersed is obtained. Further, in Examples 1, 2-1 to 2-4, and 4, precipitation was not observed immediately after production and was uniform, and in Example 2-1 although some precipitation was observed after storage, it was carried out. In Examples 2-2 and 4, it can be seen that no precipitation was observed even after storage and the mixture was uniform.

On the other hand, in Comparative Examples 1-1 to 1-4, it can be seen that the particle size of the polymer particles was so large that the Z average particle size could not be measured. It is considered that this is because the adsorption started from the non-uniform mixed state, and a large amount of aggregates were generated due to unevenness of the charged substance and the like. Further, in Comparative Examples 1-1 to 1-4 and 2, it can be seen that the precipitation was remarkably separated immediately after production and after storage. In Examples 2-3 and 4, the Z average particle diameter of the polymer particles is smaller than that of the polymer particle body, and therefore the degree of aggregation is smaller than 1, but the particle body dispersion before production is also used. No agglomerates were observed in the polymer dispersion after production, which is considered to be due to a measurement error.

The present invention is useful in the technical field of methods for producing polymer particles.

22 pores

Claims (5)

A method for producing polymer particles in which a charged substance having a charge opposite to that of the polymer particle body is adsorbed on the surface of a polymer particle body having a Z average particle diameter of 10 nm or more and 900 nm or less .
The particle body dispersion liquid in which the polymer particle body is dispersed and the charged substance-containing liquid containing the charged substance are each flowed and merged, and the merged fluid has a pore diameter of 0 at a flow rate of 5 m / s or more. Distribute to pores of .03 mm or more and 20 mm or less,
A method for producing polymer particles, wherein the ratio of the flow rate of the particle body dispersion liquid before merging to the flow rate of the charged substance-containing liquid before merging is 0.01 or more and 5 or less . The method for producing polymer particles according to claim 1, wherein the polymer particle body is formed of an anionic polymer and the charged substance is a cationic group-containing substance. The method for producing polymer particles according to claim 1, wherein the polymer particle body is formed of a cationic polymer and the charged substance is an anionic group-containing substance. In the particle body dispersion liquid and the charged substance-containing liquid to be merged, the functional group having the charge of the charged substance in the charged substance-containing liquid with respect to the charged functional group of the polymer particle body in the particle body dispersion liquid. The method for producing polymer particles according to any one of claims 1 to 3, wherein the molar ratio of the above is 0.01 or more and 50 or less. The polymer according to any one of claims 1 to 4, wherein the ratio of the content of the charged substance to the content of the polymer particle body in the fluid flowing through the pores is 1% by mass or more and 30% by mass or less. How to make particles.

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