KR20170042478A - Method for producing spherical polyorganosilsesquioxane particles - Google Patents

Abstract

The present invention provides a method for effectively producing spherical polyorganosilsesquioxane particles in which indeterminate form particles are not mixed, wherein the spherical polyorganosilsesquioxane particles can be produced without changing the particle size even when a production scale is large. A method for producing spherical polyorganosilsesquioxane particles having an average particle size of 0.5 to 30 m comprises the steps of: (i) obtaining a transparent solution by adding organoalkoxysilane represented by formula, R^1Si(OR^2)_3, in water having pH of 4.0 to 7.0 and by performing hydrolysis (in formula, R^1 represents a C1 to 20 monovalent hydrocarbon group, and R^2 represents a C1 to 6 monovalent hydrocarbon group); (ii) mixing a solution obtained in step (i) with an alkaline material or a solution having an alkaline material dissolved therein in a line mixer; and (iii) precipitating polyorganosilsesquioxane particles while being stationed after the mixing of step (ii).

Description

FIELD OF THE INVENTION [0001] The present invention relates to a method for producing spherical polyorganosilsesquioxane particles,

The present invention relates to a process for producing spherical polyorganosilsesquioxane particles having an average particle diameter of 0.5 to 30 mu m.

The polyorganosilsesquioxane particles are used as a light diffusing agent, an antiblocking agent for plastic film or paper, an agent for improving the feel of a cosmetic such as a foundation or a skin care product, a quenching agent for paints, a spreadability improving agent for a cleaner wax, .

As a method for obtaining spherical polymethylsilsesquioxane particles, there is a method of adding methyltrimethoxysilane or methyltriethoxysilane to an aqueous solution of an alkali metal hydroxide, ammonia or organic amine under stirring to perform hydrolysis and condensation reaction (Patent Document 1: Japanese Examined Patent Publication (Kokai) No. 40-16917), a method in which methyl trialkoxysilane is used as an upper layer and an aqueous solution of ammonia or amine is used as a lower layer to conduct hydrolysis and condensation reaction at these interfaces Methyltrialkoxysilane is mixed with water to obtain a homogeneous solution, followed by addition of alkali, followed by stirring and homogeneous mixing, stirring is then stopped, and condensation reaction is carried out under the conditions of a condensation reaction (Patent Document 3: JP-A-4-88023) and the like are known. Further, as a method for obtaining spherical polyorganosilsesquioxane microparticles, for example, a method in which a trialkoxysilane containing an organic group other than a methyl group is used in Patent Document 4 (Japanese Patent Application Laid-open No. 4-202325) There is disclosed a method of manufacturing the same in the same manner as in Patent Document 1 or Patent Document 3.

However, in the method in which the organotrialkoxysilane is added to an aqueous alkali solution under stirring to perform the hydrolysis and condensation reaction, particularly when the amount of the organotrialkoxysilane is increased, solid agglomerated particles of several millimeters are partially generated, Even if pulverized, it becomes irregularly shaped particles. The aggregated particles can be removed using a sieve, but the yield is lowered.

In the method of hydrolyzing and condensing the methyl trialkoxy silane as the upper layer and the aqueous alkaline solution as the lower layer at these interfaces, it is difficult to maintain the reaction interface between the silane and the aqueous alkali solution, and when the production scale is large There is a problem that production takes time and production efficiency is lowered.

There is no problem in the above-mentioned method in which the organotrialkoxysilane is stirred with water to prepare a homogeneous solution, and then the alkali is added and stirred, uniformly mixed, and then the stirring is stopped and the condensation reaction is carried out under the above conditions. However, this method has a problem that the particle size may be changed depending on the production scale.

Japanese Patent Publication (Tokukai) No. 40-16917 Japanese Patent Application Laid-Open No. 63-77940 Japanese Patent Laid-Open No. 4-88023 Japanese Patent Laid-Open Publication No. 4-202325

Accordingly, an object of the present invention is to provide a process for producing spherical polyorganosilsesquioxane particles free from the above problems.

The inventors of the present invention have made intensive studies in order to achieve the above object, and as a result, have found that, in the method for obtaining spherical polymethylsilsesquioxane particles, even in large scale production, Particles were obtained, and the present invention was completed.

That is,

The present invention provides a process for producing spherical polyorganosilsesquioxane particles having an average particle size of 0.5 to 30 탆, characterized by having the following steps (i), (ii) and (iii)

(i) a compound represented by the following general formula (1)

R^OneSi (OR²)₃ (One)

(Wherein R ¹ represents an unsubstituted or substituted monovalent hydrocarbon group of 1 to 20 carbon atoms and R ² represents a monovalent hydrocarbon group of 1 to 6 carbon atoms)

Is added to water having a pH of 4.0 to 7.0 to conduct a hydrolysis reaction to obtain a transparent aqueous solution

(ii) a step of mixing the aqueous solution obtained in the step (i) and an aqueous solution in which an alkaline substance or an alkaline substance is dissolved in a line mixer

(iii) a step of precipitating polyorganosilsesquioxane fine particles in a stationary state after the mixing of the step (ii)

According to the present invention, spherical polyorganosilsesquioxane particles in which amorphous particles are not mixed can be produced efficiently, and even if the production scale is enlarged, the particle size can not be changed.

1 is a flow chart showing an example of a procedure for producing polyorganosilsesquioxane particles by applying the present invention.

The present invention is a process for producing spherical polyorganosilsesquioxane particles having an average particle size of 0.5 to 30 탆, characterized by having the following steps (i), (ii) and (iii).

(i) a compound represented by the following general formula (1)

R^OneSi (OR²)₃ (One)

(Wherein R ¹ represents an unsubstituted or substituted monovalent hydrocarbon group of 1 to 20 carbon atoms and R ² represents a monovalent hydrocarbon group of 1 to 6 carbon atoms)

Is added to water having a pH of 4.0 to 7.0 to conduct a hydrolysis reaction to obtain a transparent aqueous solution

(ii) a step of mixing the aqueous solution obtained in the step (i) and an aqueous solution in which an alkaline substance or an alkaline substance is dissolved in a line mixer

(iii) a step of precipitating polyorganosilsesquioxane fine particles in a stationary state after the mixing of the step (ii)

The term " spherical " in the present invention includes modified spheres in which the shape of the particles is spherical, and the length of the longest axis / the length (aspect ratio) of the shortest axis is in the range of 1 to 1.5 on average. The shape of the particles can be confirmed by observing the particles with an electron microscope.

Hereinafter, each step will be described in detail.

Step (i)

In the present invention, an organotrialkoxysilane represented by the following general formula (1) is used as a raw material.

R^OneSi (OR²)₃ (One)

(Wherein R ¹ represents an unsubstituted or substituted monovalent hydrocarbon group of 1 to 20 carbon atoms and R ² represents an unsubstituted monovalent hydrocarbon group of 1 to 6 carbon atoms)

In the general formula (1), R ¹ is an unsubstituted or substituted monovalent hydrocarbon group of 1 to 20 carbon atoms. R ^{1 is preferably a} methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, decyl group, undecyl group, dodecyl group, , An octadecyl group, a nonadecyl group, and an icosyl group; Alkenyl groups such as a vinyl group and an allyl group; Aryl groups such as phenyl, tolyl and naphthyl; Aralkyl groups such as a benzyl group and a phenethyl group; A cycloalkyl group such as a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group; And a part or all of the hydrogen atoms bonded to the carbon atoms of these groups may be replaced with atoms and / or amino groups such as halogen atoms (fluorine, chlorine, bromine and iodine), acryloyloxy groups, methacryloyloxy groups, , A glycidoxy group, a mercapto group, and a carboxyl group. In order to obtain spherical particles, it is preferable that R ¹ is a methyl group, a vinyl group, an acryloyloxy group, a methacryloyloxy group, or a phenyl group.

R ² is a monovalent hydrocarbon group of 1 to 6 carbon atoms. Examples of R ² include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group, but a methyl group is preferable for obtaining spherical particles. The organotrialkoxysilane may be used alone or in combination of two or more.

In the present invention polyorganosilsesquioxane it is, but consisting of the general formula R ¹ SiO _3/2 units, and the R ¹ ₂ SiO _2/2 units, R _{¹ 3} SiO _^1/2 units and SiO _{4 / When} at least one of the _two units is to be introduced, at least one of R ¹ ₂ Si (OR ² ) ₂ , R ¹ ₃ SiOR ² and Si (OR ² ) ₄ corresponding to each of them may be added , R < ¹ > and R < ² > are as defined above. R ¹ Si (OR ²⁾ ₃ and _{^{R 1 2 Si (OR 2)}} 2, R 1 3 SiOR 2 and Si (OR ²⁾ the case of using at least one of _{^{4, R 1 Si (OR 2}} ) content of ₃ Is preferably 70 mol% or more, and more preferably 80 mol% or more, of the alkoxysilane.

In the step (i), the organotrialkoxysilane represented by the general formula (1) is added to water having a pH of 4.0 to 7.0, and a hydrolysis reaction is carried out to obtain a transparent aqueous solution.

The water used in the present step needs to have a pH of 4.0 to 7.0 in order to hydrolyze the organotrialkoxysilane. If the pH is lower than 4.0 or higher than 7.0, the condensation reaction proceeds and a gel is formed. And preferably in the range of 5.0 to 6.8. For example, if the water used here is ion-exchanged water, the pH is in the above range due to the carbonic acid dissolution in the air, so that it can be used as it is. A small amount of an acidic substance may be added to adjust the pH to the above range. The acidic substance is not particularly limited and includes, for example, carboxylic acids such as formic acid, acetic acid, oxalic acid, malonic acid, lactic acid and malic acid, hydrochloric acid; Phosphoric acid; Sulfuric acid; Methanesulfonic acid; Trifluoromethanesulfonic acid, and the like.

In this step, a water-soluble organic solvent may be added to water for the purpose of improving the hydrolysis reaction rate of the organotrialkoxysilane or controlling the particle diameter of the polyorganosilsesquioxane particles. The organic solvent used herein is not particularly limited as long as it is water-soluble, and examples thereof include alcohols such as methanol, ethanol, propanol and butanol, and ketones such as acetone.

The amount of the organotrialkoxysilane to be added is preferably 1 to 40 parts by weight, based on 100 parts by weight of the water used in the step (i) and the water for dissolving the alkaline substance in the step (ii) The amount added is preferably in the mass. If the amount of the organotrialkoxysilane is small, the production efficiency is deteriorated, and if it is large, the gel is produced in the step (iii). More preferably 10 to 30 parts by mass.

In the step (i), it is preferred that the organol alkoxysilane is added to water and the hydrolysis reaction of the organotrialkoxysilane is carried out with stirring using a conventional stirrer such as a propeller blade, a turbine blade, and a paddle blade. The organotrialkoxysilane may be added at once, but may be slowly added over time. On the contrary, water may be added to the organotrialkoxysilane, or may be added and mixed simultaneously in the bath. The temperature at this time is not limited, and may be set in the range of 0 to 100 캜. By hydrolysis Organic notes Lee alkoxysilane of the general formula R ¹ Si (OH) ₃ and the organosilane triol represented by (R ¹ represents the same meanings as R ¹ in the general formula (1)), and alcohol This is a by-product. Thus, the silane becomes soluble in water containing alcohol and becomes a transparent aqueous solution.

Stirring is continued until a clear aqueous solution is obtained. The time varies depending on the hydrolysis reaction rate, that is, the type of organotrialkoxysilane, the pH of the water, and the reaction temperature. Also, it varies depending on the addition amount of the organotrialkoxysilane.

Step (ii)

This step is a step of mixing an aqueous solution of the silane obtained in the step (i) and an aqueous solution in which an alkaline substance or an alkaline substance is dissolved in a line mixer.

The alkaline substance acts as a condensation reaction catalyst of the hydrolyzed organotrialkoxysilane, that is, organosilane triol, thereby producing polyorganosilsesquioxane particles in step (iii). The alkaline substance may be used alone or in combination of two or more. The alkaline substance may be added as it is, but since it is necessary to dissolve the alkaline substance uniformly in water in a short time, it is preferable to add the alkaline substance in the form of an aqueous solution. The amount of the alkaline substance is required to be such that at least the condensation reaction proceeds in the step (iii) to produce polyorganosilsesquioxane particles. The minimum required amount differs depending on the pH of the water in step (i), the kind of organotrialkoxysilane, the type of alkaline substance, and the reaction temperature, but the amount of water used in step (i) and the alkaline substance in step (ii) For example, 0.001 parts by mass or more, and particularly preferably 0.01 parts by mass or more, based on 100 parts by mass of water combined with water for dissolution, for example, in the case of 28% ammonia water. If the amount of the alkaline substance is too large, the rate of the condensation reaction is accelerated, and the polyorganosilsesquioxane particles are produced in the step (ii) and a gel is produced. Therefore, it is necessary to suppress the amount of polyorganosilsesquioxane particles in the step (ii) so as not to generate polyorganosilsesquioxane particles. The maximum amount varies depending on the type of organotrialkoxysilane, the amount of organotrialkoxysilane to water, the kind of alkaline substance, or the reaction temperature, but the amount of water used in step (i) and the alkaline substance in step (ii) For example, 1.0 part by mass or less, and particularly preferably 0.5 part by mass or less, based on 100 parts by mass of water combined with water for dissolution, for example, in the case of 28% ammonia water.

The alkaline substance used herein is not particularly limited, and examples thereof include alkali metal hydroxides such as potassium hydroxide, sodium hydroxide and lithium hydroxide; Alkaline earth metal hydroxides such as calcium hydroxide and barium hydroxide; Alkali metal carbonates such as potassium carbonate and sodium carbonate; ammonia; Tetraalkylammonium hydroxides such as tetramethylammonium hydroxide and tetraethylammonium hydroxide; Or amines such as monomethylamine, monoethylamine, monopropylamine, monobutylamine, monopentylamine, dimethylamine, diethylamine, trimethylamine, triethanolamine and ethylenediamine. Of these, ammonia water is preferable which can be easily removed from the obtained polyorganosilsesquioxane particles by volatilization.

In the step (ii), the silane aqueous solution obtained in the step (i) is mixed with an aqueous solution in which an alkaline substance or an alkaline substance is dissolved by using a line mixer. When the whole amount of the aqueous solution in which the alkaline substance or the alkaline substance is dissolved in the total amount of the aqueous solution of the silane is added in the batchwise manner and the aqueous solution containing the alkaline substance or the alkaline substance dissolved therein is mixed in the batchwise manner, It takes time until the aqueous solution in which the alkaline substance or the alkaline substance is dissolved is uniformly dissolved in the aqueous solution of the silane. The time difference until the aqueous solution in which the alkaline substance or the alkaline substance is dissolved is uniformly dissolved may affect the particle size of the resulting polyorganosilsesquioxane. On the other hand, it can be seen that, in the case of mixing by the line mixer, the scale of the mixing process can be made small even if the manufacturing scale is increased.

The type and shape of the line mixer used in the present invention are not particularly limited as long as an aqueous solution in which an alkaline substance or an alkaline substance is dissolved is uniformly dissolved in an aqueous solution of silane in a short period of time so that there is no driving part like a static mixer, A static mixer having a shape having a partition plate and a displacement plate, and a stirrer having a stirring blade rotating in the pipe. Examples of the stirring blade include a conventional stirrer such as a propeller blade, a turbine blade, and a paddle blade, a ribbon-screw type stirrer, a shape having a sawtooth edge on the outer periphery of the disk or a shape including a turbine and a stator such as a homomixer Type stirrer, or the like, and a baffle may be provided. The size (inner diameter) of the line mixer is not limited. However, when the line mixer is excessively large, a difference in particle diameter may occur. The inner diameter is preferably 3 mm to 500 mm, particularly preferably 10 mm to 100 mm. There is no limitation on the length of the line mixer. However, since the gel is produced when polyorganosilsesquioxane particles are produced in the line mixer, it is necessary to set the length so that polyorganosilsesquioxane particles can not be produced in the line mixer. Therefore, the length is preferably 5 mm to 10 m, particularly preferably 10 mm to 5 m.

It is preferable that the supply to the line mixer is performed by a pump so that the aqueous solution of the silane and the aqueous solution containing the alkaline substance or the alkaline substance are mixed at a predetermined ratio. The feed should be at a rate such that the mixing time in the line mixer is shorter than the time at which the polyorganosilsesquioxane particles are produced. When polyorganosilsesquioxane microparticles are produced in a line mixer, a gel is produced. If the alkali is uniformly dissolved in the aqueous solution of silane, the mixing time in the line mixer may be short, i.e., less than 1 second.

The piping to the line mixer may be such that the aqueous solution of the silane and the aqueous solution containing the alkaline substance or the alkaline substance are mixed in the feed port of the line mixer or the aqueous solution in which the alkaline substance or the alkaline substance is dissolved is mixed in the middle of the line mixer have. When the aqueous solution of the silane and the aqueous solution in which the alkaline substance or the alkaline substance is dissolved is used as a pipe joining in front of the feed port of the line mixer, the distance from the confluence point to the feed port of the line mixer is preferably short.

The temperature at the time of mixing is preferably 0 to 80 占 폚, more preferably 0 to 60 占 폚. If the temperature is higher than 80 deg. C, the production time of the polyorganosilsesquioxane particles is shortened, and it may become difficult to pass the polyorganosilsesquioxane particles through the line mixer before they are produced.

Step (iii)

This step is a step of precipitating polyorganosilsesquioxane fine particles in a stationary state after mixing with a line mixer.

After mixing the line mixer in the step (ii), the mixed solution is placed in a tank and allowed to stand. If the flow of the liquid is severe, a gel is generated. Therefore, it is preferable to use a pipe supplied from the bottom portion of the tank so as not to flow as much as possible.

When the fine particles are generated, the liquid becomes cloudy. Since the particles are not sufficiently solidified even if they are opaque, they are allowed to stand for a while. When stirring is carried out in a state where it is not solidified, the particles agglomerate or generate gel. The required standing time differs depending on the condensation reaction rate, that is, the kind of the organotrialkoxysilane, the kind and amount of the alkali substance, and the reaction temperature, but is preferably from 5 minutes to 24 hours, more preferably from 10 minutes to 12 hours .

After the completion of the step (iii), an organotrialkoxysilane of a species having an organic group different from the organotrialkoxysilane used, or an organotin alkoxysilane of R ¹ ₂ Si _{^{(OR 2) 2, R 1}} 3 SiOR 2, Si (OR 2) 4 and [(CH _{3) 3} Si] by the addition of one or more of the ₂ NH, may be a condensation reaction (these formulas, R ¹ and R ² is as described above.

Further, after the step (iii), an alkaline substance may be added or heated at 40 to 100 DEG C under stirring to complete the condensation reaction.

Further, after the step (iii), if necessary, an acidic substance may be added and neutralized under stirring.

After the condensation reaction, water and alcohols produced by the hydrolysis reaction are removed from the aqueous dispersion of the obtained polyorganosilsesquioxane particles, whereby desired spherical polyorganosilsesquioxane microparticles can be obtained. The removal of water can be carried out, for example, by heating the aqueous dispersion after the reaction under atmospheric pressure or under reduced pressure. More specifically, the dispersion can be removed by standing under heating to remove moisture, A method of spraying and dispersing a dispersion in a hot air stream such as a spray dryer, a method of using a heat transfer medium, and the like. Further, as a pretreatment of this operation, the dispersion may be concentrated by methods such as heat dehydration, filtration, centrifugation, decantation, etc., and if necessary, the dispersion may be washed with water or alcohol.

When the product obtained by removing water from the aqueous dispersion after the reaction is aggregated, it may be pulverized by a pulverizer such as a jet mill, a ball mill or a hammer mill.

Thus, spherical polyorganosilsesquioxane particles having an average particle diameter of 0.5 to 30 占 퐉 can be obtained.

<Examples>

Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples, but the present invention is not limited to these examples.

The average particle diameter of the polymethylsilsesquioxane particles is an average particle diameter based on volume at 25 占 폚 measured with an electric resistance method particle size distribution analyzer "Multisizer 3" (manufactured by Beckman Coulter, Inc.).

[Example 1]

In a 10-liter glass flask, 8,162 g of ion-exchanged water was charged, and the water temperature was set to 15 캜. The pH of the ion-exchanged water was measured to be 5.8. Under agitation at an impeller speed of 150 rpm, 870 g of methyltrimethoxysilane 1 was added to this ion-exchanged water while stirring was carried out, and the solution became transparent after 15 minutes from the addition . The solution was maintained at a temperature of 15 to 20 占 폚 and stirred for another 1 hour to obtain an aqueous solution of the hydrolyzate of methyltrimethoxysilane. The temperature after one hour from the start of the stirring was set at 15 캜.

8 g of a 28% ammonia aqueous solution and 792 g of ion-exchanged water were charged into a 1-liter glass flask, and the temperature was set at 15 캜.

As shown in Fig. 1, an aqueous solution of the hydrolyzate of methyltrimethoxysilane and an aqueous ammonia solution were mixed with a line mixer "TK pipeline homomixer M type" (manufactured by Primix Co., Ltd.) 30 mm, length 30 mm). In the method of supplying the mixture to the line mixer, a vinyl hose was put in each flask, and the mixture was sucked from there through a gear pump and supplied to a line mixer. The stirring speed of the homomixer was 3,000 rpm. The supply time of each liquid was 2 minutes and 40 seconds, the supply amount of the aqueous solution of the hydrolyzate of methyltrimethoxysilane was 9,100 g, and the supply amount of the aqueous ammonia solution was 500 g.

The mixed solution discharged from the line mixer was introduced into a 10-liter glass flask. The tip of the supply vinyl hose was positioned at the bottom of the flask so that the liquid flowing into the flask could not flow as much as possible. The temperature of the liquid flowing into the 10-liter glass flask was 16 占 폚. After 18 minutes from the start of feeding into a 10-liter glass flask, clouding of the liquid in the flask occurred. After confirming cloudiness, the solution in the flask was again allowed to stand for 3 hours, and stirring was started under the condition of a blade rotation speed of 150 rpm. Simultaneously with the stirring, the liquid in the flask was heated to 75 캜, 380 g of a 28% aqueous ammonia solution was added, and stirring was performed again at a temperature of 73 to 77 캜 for 1 hour.

The obtained liquid was dewatered by using a pressure filter to obtain a cake, and the cake was dried in a hot-air circulating dryer at a temperature of 105 ° C, and the dried material was pulverized with a jet mill to obtain polymethylsilsesquioxane particles.

The shape of the polymethylsilsesquioxane particle was observed by an electron microscope and found to be spherical.

The average particle diameter of the polymethylsilsesquioxane particles was measured using an electric resistance method particle size distribution analyzer &quot; Multisizer 3 &quot; (manufactured by Beckman Coulter, Inc.), and found to be 5.0 mu m.

[Comparative Example 1]

789 g of ion-exchanged water was charged into a 1-liter glass flask, and the water temperature was set to 15 캜. The pH of the ion-exchanged water was measured and found to be 5.9. 170 g of methyltrimethoxysilane was added to the ion-exchange water under agitation with an anchor-type stirring blade under the condition of a wing rotation speed of 150 rpm, and heat was generated. After 15 minutes from the injection, the liquid became transparent. The solution was maintained at a temperature of 15 to 20 占 폚 and stirred for another 1 hour to obtain an aqueous solution of the hydrolyzate of methyltrimethoxysilane. The temperature after 1 hour from the start of stirring was set at 15 캜.

To the aqueous solution of the hydrolyzate of the methyltrimethoxysilane was added a mixed solution of 0.5 g of 28% ammonia aqueous solution and 2.5 g of ion-exchanged water, stirred for 1 minute, and then stirred. After 16 minutes of stirring stoppage, clouding occurred. After confirming cloudiness, the solution in the flask was again allowed to stand for 3 hours, and stirring was started at a rotation speed of 150 rpm. Simultaneously with the stirring, the liquid in the flask was heated to 75 캜, 38 g of 28% ammonia aqueous solution was added, and stirring was performed again at 73 to 77 캜 for 1 hour.

The obtained liquid was dewatered by using a pressure filter to obtain a cake, and the cake was dried in a hot-air circulating dryer at a temperature of 105 ° C, and the dried material was pulverized with a jet mill to obtain polymethylsilsesquioxane particles.

The shape of the polymethylsilsesquioxane particle was observed by an electron microscope and found to be spherical.

The average particle diameter of the polymethylsilsesquioxane particles was measured using an electric resistance method particle size distribution analyzer &quot; Multisizer 3 &quot; (manufactured by Beckman Coulter, Inc.), and found to be 5.0 mu m.

[Comparative Example 2]

7,890 g of ion-exchanged water was introduced into a 10-liter glass flask, and the temperature of the water was set to 15 캜. The pH of the ion-exchanged water was measured to be 6.0. While 1,100 g of methyltrimethoxysilane was added to the ion-exchange water while stirring with an anchor-type stirring blade under the condition of a wing rotation speed of 150 rpm, heat generation occurred, and the solution became transparent after 15 minutes from the injection. And further stirred for 1 hour to obtain an aqueous solution of the hydrolyzate of methyltrimethoxysilane. The temperature after one hour from the start of the stirring was set at 15 캜.

To the aqueous solution of the hydrolyzate of the methyltrimethoxysilane was added a mixed solution of 5 g of 28% ammonia aqueous solution and 25 g of ion-exchanged water, stirred for 1 minute, and then stirring was stopped. After 15 minutes of stirring stoppage, clouding occurred. After confirming cloudiness, the solution in the flask was again allowed to stand for 3 hours, and stirring was started at a rotation speed of 150 rpm. Simultaneously with the stirring, the liquid in the flask was heated to 75 캜, 380 g of a 28% aqueous ammonia solution was added, and stirring was performed again at a temperature of 73 to 77 캜 for 1 hour.

The obtained liquid was dewatered by using a pressure filter to obtain a cake, and the cake was dried in a hot-air circulating dryer at a temperature of 105 ° C, and the dried material was pulverized with a jet mill to obtain polymethylsilsesquioxane particles.

The shape of the polymethylsilsesquioxane particle was observed by an electron microscope and found to be spherical.

The average particle diameter of the polymethylsilsesquioxane particles was measured using an electric resistance method particle size distribution analyzer &quot; Multisizer 3 &quot; (manufactured by Beckman Coulter, Inc.), and found to be 3.9 mu m.

[Example 2]

8,140 g of ion-exchanged water was charged into a 10-liter glass flask, and the water temperature was set to 30 占 폚. The pH of the ion-exchanged water was measured to be 5.8. Under stirring at 150 revolutions per minute, stirring was performed with an anchor stirrer, and 215 g of methyltrimethoxysilane 1 was added to the ion-exchanged water. Three minutes after the introduction of the methyltrimethoxysilane, It became transparent and stirred again for 5 minutes. Subsequently, 654 g of phenyltrimethoxysilane was added to this solution, stirring was continued while maintaining the temperature at 30 to 35 DEG C, and after 60 minutes from the introduction of the phenyltrimethoxysilane, the solution became transparent again, And the mixture was stirred for 5 minutes. Thereafter, the solution was cooled to 5 캜 over 55 minutes.

8 g of a 28% ammonia aqueous solution and 792 g of ion-exchanged water were charged into a 1-liter glass flask, and the temperature was adjusted to 5 캜.

As shown in Fig. 1, an aqueous solution of a hydrolyzate of methyltrimethoxysilane and phenyltrimethoxysilane and an aqueous ammonia solution were mixed in a line mixer &quot; TK Pipeline homomixer M type &quot; (Manufactured by Kagaku Kogyo Co., Ltd.). In the method of supplying the mixture to the line mixer, a vinyl hose was put in each flask, and the mixture was sucked from there through a gear pump and supplied to a line mixer. The stirring speed of the homomixer was 3,000 rpm. The supply time of each solution was 2 minutes and 40 seconds, the supply amount of the aqueous solution of the hydrolyzate of methyltrimethoxysilane and phenyl trimethoxysilane was 9,100 g, and the supply amount of the aqueous ammonia solution was 520 g.

The mixed solution discharged from the line mixer was introduced into a 10-liter glass flask. The tip of the supply vinyl hose was positioned at the bottom of the flask so that the liquid flowing into the flask could not flow as much as possible. The temperature of the liquid flowing into the 10-liter glass flask was 7 ° C. After 60 seconds from the start of feeding into a 10-liter glass flask, clouding of the liquid in the flask occurred. After confirming cloudiness, the solution in the flask was again allowed to stand for 3 hours, and stirring was started at a rotation speed of 150 rpm. Simultaneously with the stirring, the liquid in the flask was heated to 75 캜, 380 g of a 28% aqueous ammonia solution was added, and stirring was performed again at a temperature of 73 to 77 캜 for 1 hour.

The obtained liquid was dewatered by using a pressure filter to obtain a cake, and the cake was dried in a hot-air circulating dryer at a temperature of 105 ° C, and the dried material was pulverized with a jet mill to obtain polymethylsilsesquioxane particles.

The shape of the polymethylphenylsilsesquioxane particle was observed by an electron microscope to be spherical.

The average particle diameter of the polymethylphenylsilsesquioxane particles was measured using an electric resistance method particle size distribution analyzer &quot; Multisizer 3 &quot; (manufactured by Beckman Coulter, Inc.), and found to be 2.2 μm.

[Comparative Example 3]

789 g of ion-exchanged water was charged into a 1-liter glass flask, and the water temperature was set to 30 占 폚. The pH of the ion-exchanged water was measured and found to be 5.9. 110.5 g of methyltrimethoxysilane was added to this ion exchange water while stirring was carried out with an anchor type stirring wing under conditions of a wing rotation speed of 150 rpm. Two minutes after the introduction of methyltrimethoxysilane, the liquid was transparent And it was stirred again for five minutes. To this solution, 59.5 g of phenyltrimethoxysilane was subsequently added and stirring was continued while maintaining the temperature at 30 to 35 ° C. After 45 minutes from the introduction of the phenyltrimethoxysilane, the solution became transparent, and after 5 minutes Lt; / RTI &gt; Thereafter, the solution was cooled to 5 캜 over 30 minutes.

To the aqueous solution of the hydrolyzate of methyltrimethoxysilane and phenyltrimethoxysilane was added a mixed solution of 0.52 g of 28% ammonia aqueous solution and 2.6 g of ion-exchanged water, stirred for 30 seconds, and then stirred. After 20 seconds of stirring stoppage, clouding occurred. After confirming cloudiness, the solution in the flask was again allowed to stand for 3 hours, and stirring was started at a rotation speed of 150 rpm. Simultaneously with the stirring, the liquid in the flask was heated to 75 캜, 38 g of 28% ammonia aqueous solution was added, and stirring was performed again at 73 to 77 캜 for 1 hour.

The obtained liquid was dewatered by using a pressure filter to obtain a cake, and the cake was dried in a hot-air circulating dryer at a temperature of 105 ° C, and the dried material was pulverized with a jet mill to obtain polymethylsilsesquioxane particles.

The shape of the polymethylphenylsilsesquioxane particle was observed by an electron microscope to be spherical.

The average particle diameter of the polymethylphenylsilsesquioxane particles was measured using an electric resistance method particle size distribution analyzer &quot; Multisizer 3 &quot; (manufactured by Beckman Coulter, Inc.), and found to be 2.1 μm.

[Comparative Example 4]

7,890 g of ion-exchanged water was charged into a 10-liter glass flask, and the temperature of the water was set to 30 占 폚. The pH of the ion-exchanged water was measured and found to be 5.9. And 1,105 g of methyltrimethoxysilane was added to the ion-exchange water while stirring with an anchor-type stirring wing under the condition of a wing rotation speed of 150 rpm. Three minutes after the introduction of methyltrimethoxysilane, the liquid was transparent And it was stirred again for five minutes. To this solution, 595 g of phenyltrimethoxysilane was subsequently added, and stirring was continued while maintaining the temperature at 30 to 35 ° C. After 60 minutes from the introduction of the phenyltrimethoxysilane, the mixture became transparent and stirred again for 5 minutes did. Thereafter, the solution was cooled to 5 캜 over 55 minutes.

To the aqueous solution of the hydrolyzate of methyltrimethoxysilane and phenyltrimethoxysilane was added a mixed solution of 5.2 g of 28% ammonia aqueous solution and 26 g of ion-exchanged water, stirred for 30 seconds, and then stirred. Whitening occurred after 15 seconds of stirring stop. After confirming cloudiness, the solution in the flask was again allowed to stand for 3 hours, and stirring was started at a rotation speed of 150 rpm. Simultaneously with the stirring, the liquid in the flask was heated to 75 캜, 38 g of 28% ammonia aqueous solution was added, and stirring was performed again at 73 to 77 캜 for 1 hour.

The obtained liquid was dewatered by using a pressure filter to obtain a cake, and the cake was dried in a hot-air circulating dryer at a temperature of 105 ° C, and the dried material was pulverized with a jet mill to obtain polymethylsilsesquioxane particles.

The shape of the polymethylphenylsilsesquioxane particle was observed by an electron microscope to be spherical.

The average particle diameter of the polymethylphenylsilsesquioxane particles was measured using an electric resistance method particle size distribution analyzer &quot; Multisizer 3 &quot; (manufactured by Beckman Coulter, Inc.), and found to be 3.2 탆.

As in Comparative Example 2 and Comparative Example 4, when the aqueous solution of silane and the aqueous solution of alkali were mixed in a flask in a scale of about 10 kg, as in Comparative Example 1 and Comparative Example 3, The average particle size of the polymethylsilsesquioxane particles was different. However, when the aqueous solution of the silane and the aqueous solution of the alkali were mixed using a line mixer as in Example 1 or Example 2, The average particle size of the methyl silsesquioxane particles was almost the same.

Industrial Applicability According to the present invention, spherical polyorganosilsesquioxane particles in which amorphous particles are not mixed efficiently can be produced efficiently, and even if the production scale is enlarged, the production scale can be manufactured without changing the particle size, and therefore, it is industrially advantageous.

1: Aqueous solution of the hydrolyzate of organotrimethoxysilane A 10-liter glass flask
2: Ammonia aqueous solution 1 liter glass flask
3: Gear pump
4: line mixer
5: 10 liter glass flask
6: Vinyl hose

Claims (1)

A process for producing spherical polyorganosilsesquioxane particles having an average particle diameter of 0.5 to 30 占 퐉, characterized by having the following steps (i), (ii) and (iii).
(i) a compound represented by the following general formula (1)
R^OneSi (OR²)₃ (One)
(Wherein R^OneRepresents an unsubstituted or substituted monovalent hydrocarbon group of 1 to 20 carbon atoms, and R²Represents a monovalent hydrocarbon group of 1 to 6 carbon atoms)
Is added to water having a pH of 4.0 to 7.0 to conduct a hydrolysis reaction to obtain a transparent aqueous solution
(ii) a step of mixing the aqueous solution obtained in the step (i) and an aqueous solution in which an alkaline substance or an alkaline substance is dissolved in a line mixer
(iii) a step of precipitating polyorganosilsesquioxane fine particles in a stationary state after the mixing of the step (ii)

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