JPH0433927A - Production of spherical silicone fine particle - Google Patents

Abstract

PURPOSE:To obtain the subject fine particle suitable for cosmetics, etc., at a low cost by suspending a specified silane compound, its partially hydrolyzed material, its low condensate and derivatives thereof in a dispersion medium in the presence of a nonionic surfactant and carrying out hydrolysis condensation. CONSTITUTION:A hydrolyzable silane compound represented by the formula (R is H, 1-18C alkyl, 6-14C aryl or 2-18C alkenyl; X is H, OH, 1-4C alkoxy or acyloxy; n is 0-3), its partially hydrolyzed material, its low condensate and/or derivatives thereof are suspended in a dispersion medium in the presence of a basic catalyst such as sodium hydroxide or an acid catalyst using a nonionic surfactant (preferably oxyethyleneoxypropylene type block copolymer) and subsequently subjected to hydrolysis condensation, thus giving the objective fine particle having 0.5-100mum average particle size and suitable for a filler, a flatting agent, an anti-blocking agent, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for producing spherical silicone fine particles. More specifically, it relates to a method for relatively inexpensively producing spherical silicone fine particles by hydrolyzing and condensing a silane compound, and the fine particles can be used in cosmetics, matting agents, fillers, solid lubricants, etc. inorganic filler,
It is useful as a surface treatment agent, etc.

[Prior Art] Various methods for obtaining silicone fine particles have been known. For example, in JP-A-54-72300, methyltrialkoxysilane or its partial hydrolyzate is mixed with an alkaline earth metal oxide or an alkali metal carbonate. A method of hydrolytic condensation in an aqueous solution containing a salt is disclosed. According to this method, the particles obtained not only contain a large amount of aggregates, but also contain hydrolysis and condensation at the interface between the water layer and methyltrialkoxysilane, so the raw material silane compound is methyltrialkoxysilane. There is a problem in that it is limited to silane compounds that easily undergo hydrolysis and condensation reactions, such as partial hydrolysates thereof. In addition, JP-A-60-13813 and JP-A-63-77940 disclose a method of hydrolyzing and condensing methyltrialkoxysilane or a partial hydrolyzate thereof in an ammonia or amine aqueous solution. The above-mentioned problem that silane compounds are limited to silane compounds in which hydrolysis and condensation reactions easily proceed has not been solved. JP-A-1-145317 describes Si as a silane compound.
Using X4 and RnS iX t-n (X-alkoxy group, etc.), Rn5JX4-1 has a silicon equivalent ratio of 0.0.
A method for producing truly spherical Norica fine particles using 5IX4 in combination with 5IX4 is disclosed, in which 5IX4 is mixed so as to be 017 to 1, and hydrolyzed and condensed in an organic solution containing at least ammonium ions as a catalyst and water exceeding the hydrolysis equivalent. There is. According to this method, since an organic solvent capable of dissolving the silane compound is used as the organic solution, it is thought that the hydrolyzed and condensed silane compound is successively precipitated to form Norica fine particles. Therefore, the particle size of the obtained particles depends on factors such as the type of organic solution, the amount of raw material silane compound, and the amount of ammonia water used as a catalyst, and most of the obtained particles have an average particle size of 1 μl or less. particles.

Therefore, in order to obtain particles with an average particle diameter of several microns, a method has been proposed in which particles are grown by sequentially adding a silane compound to the obtained particles as seed particles, but the average particle diameter is 10 microns or more. In order to obtain particles of , it is necessary to repeat the reaction many times, and it is difficult to say that this method is industrially advantageous.

[Problems to be Solved by the Invention] In view of the above circumstances, the present invention aims to produce spherical silicone fine particles having a desired average particle diameter industrially and more efficiently by suspending various silane compounds and then subjecting them to hydrolytic condensation. The aim is to provide it using an inexpensive manufacturing method.

[Means for Solving the Problems] The present invention relates to a compound of the general formula [IcoRn5JX4-n [I3] [wherein R is the same or different, each is hydrogen, an alkyl group having 1 to 18 carbon atoms, or 6 carbon atoms] ~14 aryl group or 2~ carbon atoms
18 alkenyl groups, X is hydrogen, hydroxyl group or carbon number 1
~4 alkokino group or alkoxy group, n is O~3
means a hydrolyzable silane compound, a partial hydrolyzate, or a mixture of two or more of these derivatives,
Using a nonionic surfactant, a basic catalyst is suspended in a dispersion medium in the presence of an acidic catalyst, and then hydrolyzed and condensed.The average particle size is in the range of 0.5 to 100 μl. A method for producing certain spherical silicone particles is provided.

The method for producing noricone fine particles of the present invention is different from the conventional interfacial polycondensation and solution polycondensation, and is different from the so-called!
! It is based on the turbidity polycondensation method. Therefore, the particle size of suspension droplets of silane compounds, partial hydrolysates, etc. can be easily controlled within the range of 0.5 to 100 μM by selecting the type and amount of surfactant and by controlling the stirring conditions. It is possible to obtain spherical silicone fine particles.

General formula [1
R in the hydrolyzable silane compound represented by
The alkyl group having 1 to 18 carbon atoms in the group represented by
It may be direct or branched, such as methyl, edyl, propyl, isopropyl, butyl, isobutyl, pentyl, hequinol, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl,
Bentadenle, hexadecyl, hebutadenle, octadecyl and the like can be mentioned. Examples of the aryl group having 6 to 14 carbon atoms include phenyl and naphthyl.

The alkenyl group having 2 to 18 carbon atoms may be linear or branched, and includes, for example, vinyl, allyl, 2-propenyl, isopropenyl, and the like.

The alkoxy group having 1 to 4 carbon atoms represented by X may be linear or branched, and includes, for example, methoxy, ethoxy, propoxy, isopropoxy, butoxy, and the like. Examples of the acyloxy group having 1 to 4 carbon atoms include acetoxy, propionyloxy, butyryloxy, and the like.

Specific examples of such silane compounds include the following.

Compounds of the formula [I] where n=0 [I] Compounds of the formula [1] such as tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, trimethoxysilane, triethoxysilane, etc. [1] where n=1 , ethyltrimethoxysilane, ethyltriethoxysilane, octyltriethoxysilane, octadecyltrimethoxysilane, phenyltrimethoxysilane, vinyltrimethoxysilane, vinyltriacetoxysilane, allyltrimethoxysilane, etc. of the formula [+] where n = 2 Compounds dimethyldimethquine 7ran, dimethylnoethoxylinan, diethyldimethquinanran, dimethinodibutquinsilane, diethylnoethoxynolan, nophenyldimethoxylinan, diphenylshedoxinran, methylphenyldimethoxinran, methylphenyldiethoxysilane, The raw material silane compounds, such as trimethylmethoxysilane and trimethylethoxysilane, are not limited to those exemplified; In view of ease, alkyl alkoxylans are preferred. Also,
As the silane compound, partial hydrolysates, low condensates, and derivatives thereof of the above-mentioned silane compounds can also be used.

In the present invention, the above-mentioned silane compounds, partial hydrolysates, low condensates, and derivatives thereof can be used alone or in combination of two or more.

The above silane compounds, partial hydrolysates, low condensates, and their derivatives are suspended in a dispersion medium that does not substantially dissolve these compounds or mixtures in the presence of a nonionic surfactant, and then a hydrolytic condensation reaction is carried out. However, at this time, a basic catalyst or an acidic catalyst is added to the dispersion medium. The basic catalysts used here include sodium hydroxide, potassium hydroxide,
Calcium hydroxide, potassium carbonate, ammonia, monomethylamine, etc. can be used. In addition, as an acidic catalyst,
Hydrochloric acid, sulfuric acid, acetic acid, etc. can be used. The amount of water used for hydrolysis is required to be about 1 to 10 times the total amount of silane compounds.

Additionally, if an organic tin compound such as dibutyltin dilaurate, dibutyltin diacetate, dioctyltin dilaurate, or dioctyltin diacetate is added in advance to the above-mentioned various silane compounds or mixtures used in the reaction, polymerization will be further promoted. There are many cases.

As mentioned above, a dispersion medium that does not substantially dissolve the silane compound is used, but since it is often used in the form of a hydrolytic condensation catalyst or an aqueous solution, a dispersion medium that dissolves the aqueous solution containing the catalyst is often used. Polyhydric alcohols are preferred.

Representative polyhydric alcohols include ethylene glycol, diethylene glycol, polyethylene glycol, propylene glycol, nopropylene glycol, hexyl glycol, chrycerin, and derivatives thereof. Among these, polyethylene glycol is suitable for carrying out hydrolytic condensation in a stable suspended state. However, if a lower alcohol such as methanol or ethanol in which the silane compound is soluble is used as a dispersion medium, particles will precipitate as the hydrolysis condensation progresses, making it difficult to control the particle size to a specific size. It is.

Examples of nonionic surfactants include polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, sorbitan alkylate, polyoxyethylene sorbitan alkylate, polyoxyethylene acetylene glycol, and ochinoethylene brobylene type block copolymers. Among these nonionic surfactants, oxyethylene oxypropylene type block copolymers are particularly excellent in dispersion stability.

In addition, anionic surfactants such as sodium alkylbenzene sulfonate, sodium alkyl sulfate, sodium dioctyl sulfosuccinate, sodium naphthalene sulfonate formalin condensate, alkyltrimethylammonium chloride, polyoxyethylene alkyl can be used in combination with the above nonionic surfactants. Cationic surfactants such as amines, amphoteric surfactants such as dimethylalkyl lauryl betaine and alkylglycine, inorganic fine particles such as alumina and silica, polyvinyl alcohol, polyhinylpyrrolidone, methylcellulose, ethylcellulose, hydroxypropylcellulose, sodium alginate , propylene glycol alginate, sodium polyacrylate, styrene maleic anhydride copolymer, and other polymeric dispersants may be used together as suspension stabilizers without any problem. The amount of nonionic surfactant added is 0 to the silane compound.
．． 01 to 30% by weight, preferably 0.1 to 10% by weight.

After adding the nonionic surfactant and hydrolysis condensation catalyst to a dispersion medium that does not substantially dissolve the silane compound, the silane compound is added and adjusted to a desired particle size using a homogenizer, ultrasonic disperser, etc.

The proportion of the silane compound to be added is not particularly limited, and is suitably in the range of 10 to 100% by weight based on the dispersion medium.

Thereafter, hydrolytic condensation is carried out with stirring at, for example, 20°C to 70°C for 5 to 24 hours. At that time, the nranol groups (=SiOH) generated by hydrolysis are successively condensed, and =SiOS
i: Generate connections. After the reaction is completed, the product is filtered, washed, and dried to obtain spherical silicone fine particles.

The average composition of the resulting spherical silicone particles is expressed by the formula [: % formula %] [wherein R is the same or different and each represents hydrogen, an alkyl group having 1 to 18 carbon atoms, an aryl group having 6 to 14 carbon atoms, or It is represented by an alkenyl group having 2 to 18 carbon atoms, and m means 0 to 3.

Second Example E: Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited to the Examples.

Example 1 After adding polyethylene glycol #400 809, 2.07 g of a 5% potassium hydroxide aqueous solution, and 6.0 g of pure water to a 2003+ (! reaction vessel equipped with a stirrer), oxidized water as a nonionic surfactant was added. Ethylene oxypropylene type block copolymer (manufactured by Daiichi Kogyo Yakuhin Co., Ltd.,
1.29% of the product (trade name: Diskol N509) was completely dissolved. Add 40g of methyltriethquinonolane to these mixtures.
was added, and then dispersed for 1 minute at 6400 rpm using a homogenizer (Tokushu Kika Kogyo Gen, trade name: TK Homomixer Model M). After dispersion, keep at 30°C and perform 300 rp
Stirring was continued at m for 10 hours to complete the hydrolytic condensation. Thereafter, the mixture was filtered, washed with water, and dried to obtain spherical Noricon fine particles with an average particle diameter of 17 μm.

Example 2 After adding polyethylene glycol stand 400 so@, 2.0 g of 10% potassium hydroxide aqueous solution, and pure water 209 to a 200x reaction vessel equipped with a stirrer, oxyethylene was further added as a nonionic surfactant. Oxypropylene type block copolymer (manufactured by Daiichi Kogyo Yakuhin Co., Ltd.,
1.2 g of Diskol N509 (trade name) was completely dissolved. Partial hydrolyzate 409 of octyltrimethoxine oran was added to these mixed solutions, and after a few minutes, the mixture was dispersed at 500 rpm for 5 minutes.

After dispersion, the mixture was maintained at 30° C. and stirred at 300 rpm for 10 hours to complete hydrolytic condensation. Thereafter, it was filtered, washed with water, and dried to obtain spherical silicone fine particles with an average particle diameter of 47.5 μm.

Example 3 As the silane compound described in Example 1, 30 g of octyltrimethynesilane and a partial hydrolyzate of tetraethquinsilane 109 were used instead of methyltriethoxynolane, and 4.09 g of 5% potassium hydroxide solution was used as a catalyst. The same procedure as in Example 1 was carried out except that hydrolytic condensation was carried out to obtain spherical silicone fine particles having an average particle diameter of 1.3 μm.

Comparative Example 1 The same procedure as Example 2 was carried out except that methanol was used instead of polyethylene glycol #400 described in Example 2, but particles fused together during hydrolytic condensation and spherical silicone fine particles were not obtained. Ta.

Comparative Example 2 The same procedure as in Example 2 was carried out except that the oxyethylene oxypropylene type block copolymer was not used as the nonionic surfactant described in Example 2. During hydrolytic condensation, particles were fused and formed into a spherical shape. No silicone particles were obtained.

[Effects of the Invention] By the method of the present invention, spherical silicone fine particles having an average particle diameter of 0.5 to 100 μm can be produced industrially and at low cost. Furthermore, by changing the combination of raw material silane compounds, particles with different specific gravity and affinity with various base materials can be obtained.

These particles are used as fillers, matting agents, antiblocking agents, surface treatment agents, etc. for various materials.

Claims (4)

[Claims] (1) General formula [I]: R_nSiX_4_-_n [I] [In the formula, R is the same or different and each represents hydrogen, an alkyl group having 1 to 18 carbon atoms, an aryl group having 6 to 14 carbon atoms, or a carbon number 2-18 alkenyl group, X is hydrogen, hydroxyl group, alkoxy group having 1-4 carbon atoms, or acyloxy group, n is 0-3] A condensate or a mixture of two or more of their derivatives is suspended in a dispersion medium using a nonionic surfactant as a dispersant in the presence of a basic catalyst or an acidic catalyst, and then hydrolyzed and condensed. A method for producing spherical silicone fine particles having an average particle diameter in the range of 0.5 to 100 μm. (2) Claims (1) in which the nonionic surfactant is an oxyethylene oxypropylene type block copolymer
) method described. (3) Claims in which the dispersion medium is a polyhydric alcohol (
1) The method described. (4) The method according to claim (3), wherein the polyhydric alcohol is polyethylene glycol.