JP2008120943A - Manufacturing method of polymer particle, polymer particle, delustering agent, resin composition, coating composition, molded article and coating film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of polymer particles which prevents the occurrence of aggregated particles and is inhibited in the foaming of the latex of the polymer particles resulting from agitation or transfer. <P>SOLUTION: In the method of manufacturing polymer particles by adding a vinyl monomer, a polymerization initiator soluble in the monomer and a first surfactant in an aqueous medium, starting the polymerization after the emulsification of them and adding a second surfactant after the start of the polymerization, a reactive surfactant is used as the second surfactant. The second surfactant is preferably added between 2 and 50% polymerization conversion ratio of the vinyl monomer. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention is a polymer for stably producing a polymer having a particle size suitable for uses such as a matting agent, a light diffusing agent, a resin film anti-blocking agent, a cosmetic filler, and a slipperiness imparting agent for resin or paint. The present invention relates to a method for producing particles, polymer particles, a matting agent, a resin composition, a coating composition, a molded article, and a coating film.

In recent years, fine polymer particles have been widely used in matting agents for resins or paints, light diffusing agents, anti-blocking agents for resin films, cosmetic fillers, slipping agents, and the like. The polymer particles are produced by polymerizing a vinyl monomer by emulsion polymerization, seed polymerization, dispersion polymerization, fine suspension polymerization, or the like.
However, it is difficult to produce a polymer having a particle size of 0.5 μm or more by emulsion polymerization, which is not suitable for the above-mentioned use. In seed polymerization, a polymer having a particle size of several μm suitable for the above-mentioned use can be produced. However, since the operation is complicated, there is a problem that the production cost is increased. Since dispersion polymerization uses a solvent such as alcohol, it has a problem of high production costs.

  In the fine suspension polymerization, a polymerizable monomer, a polymerization initiator soluble in the monomer, a surfactant, and other polymerization aids are added to an aqueous medium and emulsified, and then the polymerization is started. A method of producing polymer particles. As a result, a polymer having a particle size suitable for the application can be produced.

However, in the fine suspension polymerization, the monomer droplets repeatedly collide in the polymerization process, so that aggregated particles are likely to be generated.
If aggregated particles are present in the polymer particles, the original function of the polymer particles cannot be fully exhibited when added to the resin as a matting agent, a light diffusing agent, an anti-blocking agent or the like. Further, when a large number of aggregated particles are present in the polymer particles, there arises a manufacturing problem that it becomes difficult to transfer the polymer particle latex.

In order to solve such a problem, various methods have been proposed. For example, in the fine suspension polymerization of a polyfunctional monomer having two or more vinyl groups and a vinyl monomer in an aqueous medium containing a hardly water-soluble inorganic salt and an anionic surfactant, A method for producing crosslinked fine particles in which aggregated particles are not generated by adding an anionic surfactant into the reaction system when the polymerization conversion rate is 10 to 40% is disclosed (Patent Document 1).
However, when an anionic surfactant having no polymerizable functional group is added, foaming of the polymer particle latex is promoted by stirring and transport, and aggregated particles are generated along with foaming. In addition, Patent Document 1 does not have a description suggesting that a reactive surfactant is used as the surfactant to be added.

A production method using a reactive surfactant for fine suspension polymerization has also been proposed. For example, in a fine suspension polymerization with a high solid content concentration, there is a method for producing a polymer dispersion that can be used in a resin particle-containing composition as it is without requiring filtration and drying by using a reactive surfactant as a dispersant. It is disclosed (Patent Document 2). However, if most of the surfactant present in the initial stage of polymerization in the fine suspension polymerization is a reactive surfactant, the reactive surfactant will be incorporated into the polymer particles, so that it will not function effectively. There is a problem that a large number of occurrences occur. In order to prevent this, it is necessary to increase the surfactant present in the initial stage of polymerization. However, when the amount of the surfactant is increased, there arises a problem that emulsion polymerization occurs simultaneously and a polymer having a small particle size is generated.
Japanese Patent No. 3467399 JP 2005-281339 A

  An object of the present invention is to stably produce a polymer having a particle size suitable for uses such as matting agents for resins or paints, light diffusing agents, anti-blocking agents for resin films, cosmetic fillers, and slipping agents. The present invention provides a method for producing polymer particles, a polymer particle, a matting agent, a resin composition, a coating composition, a molded article, and a coating film.

As a result of intensive studies, the present inventors have found that polymer particles can be produced by a method that does not generate agglomerated particles and does not generate bubbles in the fine suspension polymerization method of a vinyl monomer.
That is, in the method for producing polymer particles of the present invention, a vinyl monomer, a polymerization initiator soluble in the monomer, and a first surfactant are added to an aqueous medium and emulsified, and then polymerization is started. In the method for producing polymer particles by adding a second surfactant after the start of polymerization, a reactive surfactant is used as the second surfactant.
Here, it is preferable that the second surfactant is added while the polymerization conversion rate of the vinyl monomer is 2 to 50%.

The polymer particles of the present invention are produced by the production method described above.
The matting agent of the present invention is obtained from the polymer particles.
The resin composition of the present invention is obtained by blending the polymer particles with a resin.
The coating composition of the present invention is obtained by blending the polymer particles with a coating material.
The molded body of the present invention is obtained by molding the resin composition.
The coating film of the present invention is obtained by applying the coating composition.

According to the method for producing polymer particles of the present invention, polymer particles can be produced in the fine suspension polymerization method of a vinyl monomer without the generation of aggregated particles and without occurrence of foaming.
The polymer particles of the present invention do not have aggregated particles and are suitable for use as a matting agent for resin, a light diffusing agent, and the like.
The matting agent of the present invention can impart a matting effect to a resin or paint.

According to the resin composition of the present invention, a molded article having an excellent matte appearance can be obtained.
According to the coating composition of the present invention, a coating film having an excellent matte appearance can be obtained.

In this specification, (meth) acryl means acryl or methacryl, and (meth) acrylate means acrylate or methacrylate.
In the method for producing polymer particles of the present invention, a vinyl monomer, a polymerization initiator soluble in the monomer, and a first surfactant are added to an aqueous medium, emulsified, and then polymerization is started. This is a method of adding a second surfactant later.
It is a production method in which a vinyl monomer and a polymerization initiator soluble in the monomer are emulsified in an aqueous medium, and the polymerization is carried out in a state where the vinyl monomer is emulsified and dispersed. preferable.

Examples of vinyl monomers include monofunctional non-crosslinkable monomers and polyfunctional crosslinkable monomers.
Examples of the non-crosslinkable monomer include aromatic vinyl monomers such as styrene and α-methylstyrene; methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl ( (Meth) acrylate, t-butyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, stearyl (meth) acrylate, lauryl (meth) acrylate, isobornyl (meth) acrylate, benzyl (meth) acrylate, (Meth) acrylic acid esters such as phenyl methacrylate; vinyl cyanide monomers such as (meth) acrylonitrile; vinyl ethers such as methyl vinyl ether and butyl vinyl ether; vinyl halide monomers such as vinyl chloride and vinyl bromide; Vinylidene halide monomers such as vinylidene bromide; vinyl monomers having a glycidyl group such as glycidyl (meth) acrylate and allyl glycidyl ether; hydroxyl group-containing vinyl monomers such as hydroxyethyl (meth) acrylate; ) Carboxyl group-containing vinyl monomers such as acrylic acid. These vinyl monomers may be used alone or in combination of two or more. Among these, since generation of aggregated particles can be suppressed, n-butyl (meth) acrylate, i-butyl (meth) acrylate, t-butyl (meth) acrylate, and cyclohexyl (meth) acrylate are highly hydrophobic. Monomers are preferred.

  Examples of the crosslinkable monomer include ethylene glycol di (meth) acrylate, 1,3-butylene glycol di (meth) acrylate, 1,4-butylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, and the like. Alkylene glycol di (meth) acrylate; allyl methacrylate; polyvinylbenzene such as divinylbenzene and trivinylbenzene. These crosslinkable monomers may be used individually by 1 type, and may use 2 or more types together. Among these, since generation of aggregated particles can be suppressed, ethylene glycol di (meth) acrylate, 1,3-butylene glycol di (meth) acrylate, 1,4-butylene glycol di (meth) acrylate, propylene glycol di ( A monomer having a high polymerization rate such as (meth) acrylate is preferred.

When the polymer particles of the present invention are used as a matting agent, a light diffusing agent, an anti-blocking agent or the like, a crosslinkable polymer obtained by copolymerizing a crosslinkable monomer is preferable. The content of the crosslinkable monomer in the vinyl monomer is preferably 0.5 to 40% by mass in 100% by mass of all vinyl monomers (non-crosslinkable monomer + crosslinkable monomer). .
When the content of the crosslinkable monomer is 0.5% by mass or more, the generation of aggregated particles is reduced, the matte effect when the polymer particles are used as a matting agent, and the use as a light diffusing agent. This is preferable because the light diffusion effect is high. When the content is 40% by mass or less, the degree of polymerization is easily increased, the heat resistance is not lowered due to an increase in residual double bonds, and heat removal at the time of polymerization is easy.

The polymerization initiator used in the present invention needs to be soluble in the vinyl monomer, and the solubility in water is preferably less than 0.5% by mass. If the solubility in water is less than 0.5% by mass, there is no fear of simultaneous emulsion polymerization during fine suspension polymerization, which is preferable.
Examples of the polymerization initiator include azo radical polymerization initiators such as azonitrile, azoamide, cyclic azoamidine, azoamidine, and macroazo compounds; ketone peroxide, peroxyketal, hydroperoxide, dialkyl peroxide, diacyl peroxide, peroxy Examples thereof include peroxide radical polymerization initiators such as esters and peroxydicarbonates. These polymerization initiators may be used alone or in combination of two or more.

As for the usage-amount of a polymerization initiator, 0.01-1.0 mass part is preferable with respect to 100 mass parts of vinyl monomers.
It is preferable that the amount of the polymerization initiator used is 0.01 parts by mass or more because the polymerization initiator functions sufficiently, the polymerization rate is high, and the amount of unreacted vinyl monomers decreases. If it is 1.0 part by mass or less, it is preferable because there is no rapid polymerization heat generation.

The first surfactant of the present invention is a surfactant used when a vinyl monomer, a polymerization initiator soluble in the monomer, and an aqueous medium are mixed and emulsified. As the first surfactant, a known non-reactive surfactant and / or reactive surfactant can be used, and one kind may be used alone, or two or more kinds may be used in combination. Good.
Among non-reactive surfactants, it is preferable to use an anionic surfactant because of the wide range of selection. Examples of the anionic surfactant include sodium alkyl sulfate, sodium alkyl sulfonate, sodium alkyl phosphate, and the like.

Examples of the reactive surfactant include polyoxyethylene alkyl ether having a polymerizable functional group, sulfonate or phosphate thereof; polyoxyethylene phenyl ether having a polymerizable functional group, sulfonate or phosphoric acid thereof Salt; alkyl fatty acid salt having a polymerizable functional group; alkyl sulfonic acid having a polymerizable functional group, or a salt thereof; alkyl phosphoric acid having a polymerizable functional group, or a salt thereof.
Preferred examples of the reactive surfactant include Latemul S-180, Latemuru PD-104, Latemuru PD-420, Latemuru PD-430 (manufactured by Kao Corporation); Surfmer FP-80, Surfmer FP-100, Surfmer FP-120, Surfmer FP-160, Surfmer FP-200, Surfmer FP-125 (above, manufactured by Toho Chemical Industry Co., Ltd.); Adeka Soap SE-10N, Adeka Soap SE-20N, Adeka Soap NE- 10, ADEKA rear soap NE-20, ADEKA rear soap NE-30, ADEKA rear soap NE-40, ADEKA rear soap ER-20, ADEKA rear soap ER-30, ADEKA rear soap ER-40 (above, ADEKA Corporation) Manufactured by AntoxMS-60, AntoxMS-2N (Nippon Emulsifier Co., Ltd.) Ltd.): Eleminol JS-2, ELEMINOL RS-30 (or more, manufactured by Sanyo Chemical Industries, Ltd.) and the like.

In order to suppress the generation of aggregated particles in the polymerization step, it is preferable that 60% by mass or more of the first surfactant is a non-reactive surfactant. When the content of the non-reactive surfactant is less than 60% by mass (the content of the reactive surfactant is 40% by mass or more), the reactive surfactant is taken into the polymer particles in the process of fine suspension polymerization. And aggregated particles may be generated.
0.01-5.0 mass parts is preferable with respect to 100 mass parts of vinyl monomers, and, as for the usage-amount of a 1st surfactant, 0.05-3.0 mass parts is more preferable. It is preferable that the amount of the first surfactant used is 0.01 parts by mass or more because the stability of the polymer particle latex is good and adhesion of aggregates to a stirring blade or the like can be prevented. When the amount is 5.0 parts by mass or less, foaming of the polymer particle latex is suppressed, and simultaneous occurrence of emulsion polymerization can be prevented, which is preferable.

The aqueous medium of the present invention contains water as a main component, and water-soluble solvents, salts, and the like may be added as necessary.
As for the usage-amount of an aqueous medium, 50-1000 mass parts is preferable with respect to 100 mass parts of vinyl monomers. It is preferable that the amount of the aqueous medium used be 50 parts by mass or more because heat generation during polymerization is suppressed and heat removal from the polymerization heat generation is improved. When the amount is 1000 parts by mass or less, the productivity of the polymer particles is high and preferable.

In the present invention, a vinyl monomer, a polymerization initiator soluble in the monomer, and a first surfactant are added to an aqueous medium to carry out an emulsification treatment. The emulsification treatment can be performed using a known emulsification apparatus. Examples of the emulsifier include a stirrer such as a propeller mixer and a turbine mixer; a high-speed rotary stirrer and disperser such as a homomixer; a pressure nozzle emulsifier and disperser such as a homogenizer; a colloid mill and an ultrasonic emulsifier. .
By the emulsification treatment, the mixture of the vinyl monomer and the polymerization initiator is emulsified and dispersed in the aqueous medium as fine droplets having a particle diameter of 0.5 to 100 μm, and the emulsified dispersion state is stabilized by the first surfactant. The

The vinyl monomer emulsified and dispersed in the aqueous medium is polymerized by radicals generated from the mixed polymerization initiator. The polymerization initiator used in the present invention is a thermal decomposition type, and the polymerization proceeds by heating an aqueous medium in which the vinyl monomer is emulsified and dispersed, and a polymer particle latex can be obtained.
The polymerization operation can be performed using a method known as fine suspension polymerization.

The second surfactant of the present invention is a surfactant added to the reaction system after the start of polymerization of the vinyl monomer. As the second surfactant, a known reactive surfactant can be used, and one kind may be used alone, or two or more kinds may be used in combination.
As the reactive surfactant used for the second surfactant, the reactive surfactants exemplified as the first surfactant can be used.

The second surfactant has a reactive surfactant as a main component, but may contain a non-reactive surfactant as necessary. The content of the non-reactive surfactant is preferably less than 40% by mass, and more preferably less than 20% by mass. When the content of the non-reactive surfactant is less than 40% by mass, foaming due to the addition of the second surfactant is suppressed, and generation of aggregated particles is preferably suppressed.
As the non-reactive surfactant used for the second surfactant, the non-reactive surfactant exemplified as the first surfactant can be used.

  0.01-1.0 mass part is preferable with respect to 100 mass parts of vinyl monomers, and, as for the usage-amount of a 2nd surfactant, 0.05-0.8 mass part is more preferable. When the amount of the second surfactant used is 0.01 parts by mass or more, the generation of aggregated particles can be suppressed, which is preferable. Since it is suppressed as foaming is 1.0 mass part or less, it is preferable.

The second surfactant is preferably added to the reaction system while the polymerization conversion rate of the vinyl monomer is 2 to 50%, more preferably 5 to 35%. When the polymerization conversion rate is added at 2% or more, it is preferable that the surfactant is hardly taken into the polymer particles and the function of stabilizing the polymer particle latex is not lowered. When it is 50% or less, the generation of aggregated particles is small and the effect of adding a surfactant is large, which is preferable.
The second surfactant may be added all at once in the reaction system or may be added dropwise over a certain period of time. Moreover, you may throw in as aqueous solution diluted with water as needed.

  The reactive surfactant added as the second surfactant is fixed to the surface of the polymer particles by a polymerization reaction, and improves the stability of the polymer particle latex. By using the reactive surfactant, it is possible to prevent the surfactant from being detached from the surface of the polymer particles. The present invention is a technique for improving the stability of an emulsified dispersion of a vinyl monomer formed in the initial stage of polymerization and the stability of a polymer particle latex in the polymerization process. And a technique for increasing the particle size by introducing a pre-emulsion of a surfactant.

The polymer particles can be recovered from the polymer particle latex by appropriately selecting a method such as salting out or acid precipitation aggregation, spray drying, freeze coagulation, freeze drying and the like.
The volume average particle diameter of the polymer particles is preferably 0.5 to 100 μm, and more preferably 1.0 to 50 μm.
The polymer particles of the present invention can be used as matting agents for resins or paints, light diffusing agents, anti-blocking agents for resin films, cosmetic fillers, slipping agents, and the like.

  The polymer particles of the present invention can be blended in a resin or paint as a matting agent. By blending with a resin, a molded article having an excellent matte appearance can be obtained, and by blending with a paint, a coating film having an excellent matte appearance can be obtained.

  When blending the polymer particles of the present invention with a resin, a known resin can be appropriately selected as the base resin. For example, polycarbonate, acrylic resin, styrene resin, methyl methacrylate-styrene copolymer, polyvinyl chloride, polyolefin, acrylonitrile-styrene resin, acrylonitrile-butadiene-styrene resin, fluorine resin, polyamide, polyester, polyacetal, thermoplastic elastomer, etc. Thermosetting resins such as epoxy resins, unsaturated polyesters, phenol resins, amino resins, and the like.

  The polymer particles are preferably blended in an amount of 0.1 to 200 parts by mass with respect to 100 parts by mass of the resin. Moreover, you may mix | blend various additives with base resin. Examples of additives include various stabilizers such as antioxidants and ultraviolet absorbers; flame retardants, lubricants, antistatic agents, inorganic fillers, processing aids, impact modifiers, foaming agents, antibacterial agents, and coloring. Agents and the like.

  As a method of blending the base resin and polymer particles, for example, the resin, polymer particles, and additives as necessary are mixed with a Henschel mixer, tumbler, etc., and this is melt-mixed with an extruder, kneader, mixer, etc. And a method of sequentially mixing other components with a previously melted component.

  A molded body can be obtained by molding the blended resin composition. Examples of the molding method include extrusion molding, injection molding, calendar molding, blow molding, cast molding, press molding, and vacuum molding.

  When blending the polymer particles of the present invention in a paint, a known resin can be appropriately selected as the binder resin for paint. For example, acrylic resins, polyesters, urethane resins, epoxy resins, polyolefins, silicone resins, fluorine resins, nitrocellulose resins, etc., which are generally soluble in organic solvents. Moreover, the said resin of water solubility, a suspension, and an emulsion can also be illustrated. The binder resin for paint is usually diluted with an organic solvent or water.

  The polymer particles are preferably blended in an amount of 0.1 to 200 parts by mass with respect to 100 parts by mass of the binder resin. Moreover, you may mix | blend various additives with binder resin. Examples of additives include various stabilizers such as antioxidants and ultraviolet absorbers; pigments, dyes, colorants, antifoaming agents, thickeners, flame retardants, lubricants, antistatic agents, inorganic fillers, processing aids. Agents, antibacterial agents and the like.

  Examples of the method of blending the binder resin and the polymer particles include a method of mixing the binder resin, polymer particles, and additives as necessary with a stirrer, a kneader, a mixer, and the like.

  A coating film can be obtained by applying the blended coating composition to a substrate and drying it. Examples of the application method include spray coating, roll coating, and brush coating.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. “Part” in the examples represents “part by mass”.

(Measurement of polymerization conversion)
1) 2 ml of polymer particle latex was sampled and the mass was measured. Subsequently, 0.2 mg of polymerization inhibitor p-methoxyphenol was added and cooled.
2) The residual mass when the latex to which the polymerization inhibitor was added was heated in a hot air dryer at 105 ° C. for 5 hours was measured.
3) The polymerization conversion rate was calculated by the following formula.
Polymerization conversion rate (%) = [(mass of heating residue / mass of collected latex) / (charge amount of vinyl monomer / total amount of polymerization charge)] × 100

(Measurement of particle diameter)
The particle size of the polymer particles was measured using a laser diffraction / scattering particle size distribution measuring device (LA-910: manufactured by Horiba, Ltd.).
Ion exchange water was used as a dispersion medium for the polymer particles, and the refractive index of the polymer particles was set to 1.12.
The particle diameter in this specification was represented using the median diameter in volume average conversion by this measurement.

(Rate of aggregate)
From the mass of the aggregate floating on the polymer particle latex after polymerization, the mass of the aggregate peeled off from the stirring blade, and the charged amount of the vinyl monomer, the ratio of the aggregate was calculated by the following formula.
Aggregate ratio (%) = (mass of aggregate / preparation amount of vinyl monomer) × 100
The evaluation criteria for the ratio of aggregates are shown below.
A: Aggregate ratio is less than 1% O: Aggregate ratio is 1% or more and less than 2% Δ: Aggregate ratio is 2% or more and less than 8% X: Aggregate ratio is 8% or more

(Bubbling evaluation)
The amount of foam generated on the surface of the latex during the polymerization was visually evaluated.
The evaluation criteria for foaming are shown below.
○: A small amount of bubbles are generated around the stirring bar ×: A large amount of bubbles are generated on the entire surface of the latex

(Filterability evaluation)
After polymerization, the polymer particle latex was filtered through a # 300 mesh cloth and evaluated.
The evaluation criteria for filterability are shown below.
○: Filtering with # 300 mesh cloth is quick Δ: Filtering with # 300 mesh cloth is slow ×: Filtering with # 300 mesh cloth is difficult

<Example 1>
In a 2 liter reaction vessel equipped with a thermometer, a stirring bar, a cooling tube, and a nitrogen introduction tube, 450.0 parts of ion-exchanged water was placed, and the inside of the reaction vessel was purged with nitrogen.
The following monomer mixture was emulsified at 11,000 rpm for 1 minute using a mixer (Ultra Turrax T-25: manufactured by IKA) to obtain an emulsified dispersion. Here, the usage-amount of a 1st surfactant is 0.4 parts with respect to 100 parts of vinyl monomers.
Monomer mixture:
i-butyl methacrylate 437.0 parts n-butyl acrylate 8.8 parts ethylene glycol dimethacrylate 54.2 parts Perocta-O (manufactured by NOF Corporation) 1.0 part phosphanol RS-610NA 2.0 parts ( First surfactant Non-reactive surfactant: manufactured by Toho Chemical Co., Ltd.
Ion exchange water 500.0 parts

The emulsion dispersion of the monomer mixture was put into a reaction vessel and heated for 2 hours using a 70 ° C. hot water bath while stirring at 350 rpm.
When the polymerization conversion of the vinyl monomer was 0.12%, the following surfactant mixture was added to the reaction vessel. Here, the usage-amount of a 2nd surfactant is 0.2 parts with respect to 100 parts of vinyl monomers.
Surfactant mixture:
LATEMUL S-180 1.0 part (second surfactant reactive surfactant: manufactured by Kao Corporation)
FS Antifoam EPK 2.5 parts (Defoamer: Toray Dow Corning Co., Ltd.)
43.5 parts of ion exchange water

  Further, the temperature was raised to 80 ° C. and heating was performed for 1 hour to complete the polymerization. The obtained polymer particles had a volume average particle diameter of 5.7 μm. Agglomerated particles were not observed, and the agglomerate ratio was 6.5%. There was little foaming during polymerization, and the filtration rate with # 300 mesh cloth was slightly slow.

<Examples 2 to 6>
Polymer particles were produced in the same manner as in Example 1 except that the addition of the surfactant mixture was changed to the time of polymerization conversion shown in Table 1. Table 1 shows the volume average particle diameter of the obtained polymer particles, the ratio of aggregates, foaming during polymerization, and filterability.

<Example 7>
The composition of the monomer mixture was changed to the following contents, the conditions for the emulsification treatment were changed to 1 minute at 24,000 rpm, and the addition of the surfactant mixture was changed to the time when the polymerization conversion was 11.1%. Produced polymer particles in the same manner as in Example 1. Table 1 shows the volume average particle diameter of the obtained polymer particles, the ratio of aggregates, foaming during polymerization, and filterability.
Monomer mixture:
i-butyl methacrylate 318.8 parts methyl methacrylate 112.3 parts n-butyl acrylate 9.6 parts ethylene glycol dimethacrylate 59.3 parts perocta-O 1.0 part phosphanol RS-610NA 2.0 parts ion-exchanged water 500.0 parts

<Comparative Example 1>
Example 1 except that the second surfactant was phosphanol RS-610NA, a non-reactive surfactant, and the addition of the surfactant mixture was changed to a point of 32.5% polymerization conversion. In the same manner, polymer particles were produced. Table 1 shows the volume average particle diameter of the obtained polymer particles, the ratio of aggregates, foaming during polymerization, and filterability.

<Example 8>
The composition of the first surfactant is a combination of phosphanol RS-610NA, which is a non-reactive surfactant, and latemul S-180, which is a reactive surfactant (the ratio is described in Table 2: total 2. 0 parts), and polymer particles were produced in the same manner as in Example 1 except that the addition of the surfactant mixture was changed to the point where the polymerization conversion was 37.5%. Table 2 shows the volume average particle diameter of the obtained polymer particles, the ratio of aggregates, foaming during polymerization, and filterability.

<Examples 9 and 10>
The composition of the first surfactant is the content described in Table 2 (total: 2.0 parts), the stirring of the emulsified dispersion of the monomer mixture is changed from 350 rpm to 150 rpm, and the addition of the surfactant mixture is performed. Polymer particles were produced in the same manner as in Example 1, except that the polymerization conversion rate shown in Table 2 was changed. Table 2 shows the volume average particle diameter of the obtained polymer particles, the ratio of aggregates, foaming during polymerization, and filterability.

<Comparative example 2>
Production of polymer particles was attempted in the same manner as in Example 10 except that the surfactant mixture was not added. However, it aggregated and solidified at the peak of the polymerization exotherm.

<Recovery of polymer particles>
The polymer particle latex produced in Examples 1 to 10 and Comparative Example 1 was filtered through a # 300 mesh cloth, and then spray-dried and recovered as polymer particles.
The spray drying was performed under operating conditions of a hot air inlet temperature of 180 ° C. and a hot air outlet temperature of 75 ° C.

<Creation of molded body>
10 parts of the recovered polymer particles are blended with 100 parts of polyacetal resin (Duracon M90-34: manufactured by Polyplastics Co., Ltd.) and melt-kneaded at 200 ° C. using a twin screw extruder. Pellets were obtained.
The resin composition pellets were molded at 200 ° C. using an injection molding machine to obtain a molded body having a length of 80 mm, a width of 50 mm, and a thickness of 3 mm.

About the obtained molded object, the external appearance was evaluated by visual observation.
The evaluation criteria of the appearance of the molded body are shown below. The evaluation results are shown in Tables 1 and 2.
○: Uniform matt appearance ×: Insufficient matt appearance, non-uniform appearance

<Creation of coating film 1>
5 parts of the recovered polymer particles are blended with 100 parts of the solid content of the water-soluble paint (water-soluble glossy varnish: manufactured by Campehapio Co., Ltd.), and 180 parts by a mixer (manufactured by Kentaro Awatori: manufactured by Shinky Co., Ltd.). Mixed for 2 seconds. The coating composition was applied to the electrodeposition plate with a spatula and dried at room temperature for 30 minutes and then in an oven at 105 ° C. for 30 minutes to obtain a coating film.
<Creation of coating film 2>
5 parts of the recovered polymer particles were blended with 100 parts of the solid content of the oil-soluble paint (clear lacquer: manufactured by Campehapio Co., Ltd.), and a coating film was obtained in the same manner as in the coating film 1.

The appearance of the obtained coating film was visually evaluated.
The evaluation criteria of the appearance of the coating film are shown below. The evaluation results are shown in Tables 1 and 2.
○: Uniform matt appearance ×: Insufficient matt appearance, non-uniform appearance

  The polymer particles obtained by the production method of the present invention are free of aggregated particles, and are suitably used as matting agents for resins or paints, light diffusing agents, anti-blocking agents for resin films, cosmetic fillers, slipping agents, etc. Used.

Claims (8)

A vinyl monomer, a polymerization initiator soluble in the monomer, and a first surfactant are added to an aqueous medium, emulsified, and then the polymerization is started. After the polymerization is started, a second surfactant is added. In the method of producing polymer particles,
A method for producing polymer particles, wherein a reactive surfactant is used as the second surfactant.   The method for producing polymer particles according to claim 1, wherein the second surfactant is added while the polymerization conversion rate of the vinyl monomer is 2 to 50%.   The polymer particle obtained by the manufacturing method of the polymer particle of Claim 1 or 2.   A matting agent obtained by using the polymer particles according to claim 3.   The resin composition obtained by mix | blending the polymer particle of Claim 3 with resin.   The coating composition obtained by mix | blending the polymer particle of Claim 3 with a coating material.   The molded object obtained by shape | molding the resin composition of Claim 5.   The coating film obtained by apply | coating the coating composition of Claim 6.