JPH04370150A - Silicone oil-containing organic resin particle and production thereof - Google Patents

Abstract

PURPOSE:To provide the title particles capable of incorporation in powder coatings or powder decorative materials without impairing powder fluidity or electrical properties, also capable of incorporation in silicone oil-insoluble medium compositions without causing phase separation or maldispersion, usable as a surface regulator, etc. CONSTITUTION:The objective particles 0.05-1mum in mean size containing (A) inside them, 5-70wt.% of a silicone oil of the formula (R<1> to R<6> are each H, hydroxyl group, alkyl group, cycloalkyl group, etc.; m is such number so as to come to <=1000000 (pref. 400-100000) in the molecular weight of the siloxane skeleton) liquid at <=100 deg.C and (B) on the surface layer of them, 30 95wt.% of a thermoplastic resin 30-200 (pref. 50-200) deg.C in glass transition temperature and <=1000000 in average molecular weight, prepared from an ethylene-based unsaturated monomer (e.g. vinyl monomer). The present particles can be obtained by adding the ethylene-based unsaturated monomer to a silicone oil emulsion <=1mum in the micell's mean particle size followed by emulsion polymerization.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to silicone oil-containing organic resin fine particles and a method for producing the same. Specifically, the present invention provides a silicone oil-containing organic material that can be suitably blended into powder coatings, powder cosmetics, etc. without impairing powder fluidity or electrical properties, and can be stably dispersed even in silicone oil-insoluble media and has excellent storage stability. This invention relates to resin fine particles and their manufacturing method. More specifically, the present invention provides silicone oil-containing organic resin fine particles, which release silicone oil inside the resin particles upon heating and function as a surface conditioner, fluidity conditioner, antifoaming agent, water repellent, mold release agent, etc. and its manufacturing method.

0002

[Prior art] Silicone oil has conventionally been used as a surface conditioner,
Widely used as fluidity regulator, antifoaming agent, water repellent, mold release agent, etc. However, when silicone oil itself is directly blended into a powder coating, there is a problem in that the powder fluidity, electrical properties, etc. are significantly impaired. Furthermore, when silicone oil is added to a medium that is not compatible with silicone oil, it easily phase separates and has low dispersion stability, resulting in very poor storage stability. The problem is that silicone oil cannot be used in water-based paints, electrodeposition paints, cosmetics, etc.). As a method to solve this problem, it is proposed to modify the silicone oil into a special one. However, it is economically disadvantageous to change the modification method for silicone oil depending on the type of medium, and it is practically impossible to find a modification method for all media.

[0003] As a method for improving the powder fluidity of the powder coating described above, particles made of a composite of a thermoplastic resin and a polyorganosiloxane have been proposed. As such particles, particles in which a vinyl monomer is graft-polymerized to a polyorganosiloxane skeleton are generally known (Japanese Patent Application Laid-Open No. 62-8141).
Publication No. 2, JP-A-62-127364, JP-A-6
4-45414). These powder particles can be provided with excellent powder flowability by techniques such as spray drying.

[0004] However, all of the above powder particles are designed as impact-resistant materials and are not suitable as surface conditioners or fluidity conditioners. For example, the polyorganosiloxane of the above-mentioned composite particles is a solid with a very high molecular weight, and therefore requires a considerably high temperature to be turned into a liquid as a surface conditioner or fluidity conditioner. Also, in its particle structure, the polyorganosiloxane is partially but strongly bound to the thermoplastic resin by covalent bonds, so the thermoplastic resin and the polyorganosiloxane cannot be separated. . That is, there is an essential problem that the silicone oil cannot be eluted from the inside of the powder particles as a surface conditioner or fluidity conditioner by heating.

[0005]

[Problems to be Solved by the Invention] The present invention is suitable for use as a surface conditioner, fluidity conditioner, antifoaming agent, water repellent, mold release agent, etc. without impairing powder fluidity or electrical properties. It can be blended into powder paints and powder cosmetics, and even after a long period of time, the
An object of the present invention is to provide silicone oil-containing organic resin fine particles that can be suitably blended into a silicone oil-insoluble medium composition without causing layer separation or poor dispersion, and a method for producing the same.

[0006]

[Means for Solving the Problems] As a result of intensive studies to achieve the above object, the inventors of the present invention found that it is possible to powderize silicone oil by encapsulating an emulsion containing silicone oil with a thermoplastic resin. It becomes possible to add silicone oil to the powder coating or the above-mentioned insoluble medium composition without impairing the powder fluidity of the powder coating or the dispersion stability in the silicone oil-insoluble medium,
Furthermore, the inventors have discovered that by heating the particles after addition, the silicone oil inside the particles can be eluted and function as a surface conditioner, fluidity conditioner, etc., and the present invention has been completed.

That is, in the present invention, the organic resin fine particles have the general formula:

[Formula, R1, R2, R3, R4, R5 and R6 may be the same or different, hydrogen atom; hydroxyl group; alkyl group;
Cycloalkyl group; alkoxy group; alkenyl group; phenyl group; represents a monovalent hydrocarbon group; a polyoxyalkylene group; a vinyl polymer residue; or a fatty acid ester group,
m represents a number such that the molecular weight of the siloxane skeleton is 1,000,000 or less. ] Silicone oil 5 to 70
% by weight, and the particle surface layer contains 30 to 95 weight % of a thermoplastic resin with a glass transition temperature of 30 to 200°C prepared from an ethylenically unsaturated monomer, and an average particle diameter of 0.0
Provided are silicone oil-containing organic resin fine particles having a particle size of 5 to 1 μm. The present invention further provides the silicone oil-containing organic resin fine particles, characterized in that the ethylenically unsaturated monomer is added to an emulsion of the silicone oil [I] whose micelles have an average particle diameter of 1 μm or less and subjected to emulsion polymerization. Provide manufacturing method.

The organic resin fine particles of the present invention have the above general formula:
Contains silicone oil represented by [I]. Expression [
I] In R1 to R6, the carbon-containing group is, for example, a lower group having 1 to 20 carbon atoms, or a molecular weight of 200 to 10
,000 vinyl polymer residues and the like. Specific examples of the lower groups include methyl, ethyl, aminoethyl, aminoethylaminopropyl, glycidoxypropyl, cyclohexylepoxy, carboxypropyl, hydroxypropyl, hydroxyphenylpropyl, phenylmethylethyl, 3,3,3 -Trifluoropropyl, propyl, butyl, phenyl, lauryl, stearyl and the like. In addition, the siloxane skeleton molecular weight in formula [I] is 1,000,000 or less, preferably 20
0 to 1,000,000, more preferably 400 to 30
It is 0,000. If the skeleton molecular weight exceeds 1,000,000, the surface elution rate of the silicone oil upon heating will be delayed, which is not preferable. Furthermore, silicone oil [I] is preferably liquid at 100°C or lower, particularly 80°C or lower. If a temperature higher than 100° C. is required for liquefaction, encapsulation becomes difficult, and the silicone oil does not liquefy instantaneously, resulting in a delayed dissolution rate, which is undesirable.

As will be described later, in the production of the organic resin fine particles of the present invention, silicone oil [I] is used in the form of an emulsion. Such an emulsion of silicone oil [I] may be prepared, for example, by emulsification and ring-opening polymerization in an aqueous medium using a cyclic siloxane as a monomer and an organodisiloxane or the like as a polymerization terminator. Specific examples of the cyclic siloxane include octamethylcyclotetrasiloxane, tetraphenyltetramethylcyclotetrasiloxane, and tetramethyltetrahydrodienecyclotetrasiloxane. Specific examples of the polymerization terminator include hexamethyldisiloxane, hexaphenyldisiloxane, hexahydrodienedisiloxane, and the like. During emulsion polymerization, additives such as surfactants, polymerization catalysts, and polymerization stabilizers may be used. The emulsion polymerization composition is appropriately selected depending on the degree of polymerization, but for example, cyclic siloxane 100
The amount of polymerization terminator may be 0.1 to 20 parts by weight based on parts by weight.

[0010] The silicone oil [I] itself is a commercially available product [for example, KF-50, KF-96, KF-410,
KF-860, KF-910, KF-945, KF-3
935, KF-6002, X-22-163B, X-2
2-801B, X-22-162C, X-22-822
(manufactured by Shin-Etsu Chemical Co., Ltd.), etc.]. In this case, the emulsion of the silicone oil [I] can be prepared by, for example, melting the silicone oil [I] with heat, blending a surfactant with it, and adding an aqueous medium to it while stirring vigorously, or by emulsifying it using a Gaulin homogenizer or the like. It may be prepared using equipment.

[0011] In the emulsion of silicone oil [I] prepared as described above, the average particle diameter of micelles is 1 μm or less, preferably 0.01 to 0.8 μm. If the particle size of the micelles exceeds 1 μm, stable encapsulation of silicone oil by the thermoplastic resin described below cannot be expected.
The silicone oil separates as it dries, which is undesirable. The viscosity of the emulsion of silicone oil [I] is preferably 5 to 5,000 centipoise.

The silicone oil-containing organic resin fine particles of the present invention contain the above-mentioned silicone oil based on the total weight of the fine particles.
[I] is encapsulated with a thermoplastic resin. That is, the silicone oil-containing organic resin fine particles of the present invention are
It has a two-layer structure in which the silicone oil [I] is present in the inner core of the particle, and a thermoplastic resin is present on the surface layer of the particle covering the silicone oil [I]. The thermoplastic resin is prepared by emulsion polymerization of ethylenically unsaturated monomers as described below. Examples of ethylenically unsaturated monomers include vinyl monomers, (meth)acrylamide monomers, (meth)acrylate monomers, unsaturated mono- and di-carboxylic acid monomers, and one or more of these monomers may be used. More specifically, ethylenically unsaturated monomers include, for example, styrene, methyl or butyl (meth)acrylate, hydroxyethyl (meth)acrylate, ethylhexyl (meth)acrylate, vinyl acetate, perfluoropropyl (meth)acrylate, and ethylstyrene. ,(
Examples include meth)acrylonitrile and the like. Other monomers such as divinylbenzene, ethylene glycol di(meth)acrylate, etc. may be used in combination to the extent that the effects of the present invention are not impaired.

[0013] The thermoplastic resin on the surface layer of such fine particles is
Glass transition temperature 30-200°C, preferably 50-15
It has a temperature of 0°C. If the glass transition temperature is less than 30°C, a problem will arise in blocking resistance, and if it exceeds 200°C, the thermal meltability will decrease and silicone oil will not be released, which is not preferable. Furthermore, the average molecular weight of the thermoplastic resin is 1,000,000 or less, particularly 1,000,000 or less.
0 to 300,000 is preferred. Average molecular weight is 1,00
If it exceeds 0,000, encapsulation becomes difficult due to high viscosity, and thermal responsiveness decreases, making it impossible to release silicone oil instantly, which is not preferable.

The silicone oil-containing organic resin fine particles of the present invention contain 5 to 70% by weight of the silicone oil [I].
(preferably 10 to 50% by weight) and 30 to 95% by weight (preferably 50 to 90% by weight) of the above thermoplastic resin. Furthermore, the silicone oil-containing organic resin fine particles of the present invention have an average particle diameter of 0.05 to 1 μm, preferably 0.08 to 0.80 μm. When the particle size exceeds 1 μm, the mechanical stability of the particles decreases in the particle isolation and drying steps described below, and there is a risk that the silicone oil will separate due to particle breakage. On the other hand, the particle size is 0.
If it is smaller than 0.05 μm, it becomes impossible to disintegrate into primary particles due to the strong cohesive force between the fine particles after isolation and drying.

[0015] The production of the silicone oil-containing organic resin fine particles of the present invention as described above is carried out by using the silicone oil [
The above-mentioned ethylenically unsaturated monomer is added to the emulsion of [I] and emulsion polymerization is carried out. The ethylenically unsaturated monomer may be added before emulsion polymerization or while emulsion polymerization is being performed. Furthermore, in emulsion polymerization, it is preferable to use a polymerization degree regulator in order to obtain a desired average molecular weight of the thermoplastic resin. Examples of the polymerization degree regulator include allyl monomers and mercapto monomers, and one or more of these may be used. Specific examples of the allyl monomer include α-methylstyrene dimer, allyl alcohol, and the like. Specifically, as the mercapto monomer, for example, t
-dodecanethiol, octyl thioglycolate, thioglycolic acid and the like. Examples of emulsion polymerization initiators include radical polymerization initiators (specifically peroxide initiators, t-butyl peroctoate, potassium or ammonium persulfate, azo initiators [U-50, U-70,
U-59, U-501, U-60 (Wako Pure Chemical), etc.)
can be mentioned. Furthermore, during emulsion polymerization, a surfactant (
For example, it is preferably carried out in the presence of an anionic, cationic, or nonionic surfactant. Other additives such as polyvinyl alcohol and polyethylene oxide may be added during emulsion polymerization.

The emulsion polymerization composition is appropriately selected depending on the average molecular weight of the thermoplastic resin, but for example, 100 parts by weight of the silicone oil [I], 100 to 900 parts by weight of the ethylenically unsaturated monomer, and 0 parts by weight of the degree of polymerization regulator. .5~5
0 parts by weight and 0.1 to 10 parts by weight of the polymerization initiator are preferred. Emulsion polymerization conditions are also selected appropriately, for example, 0 to 100°C.
may be for 1 to 48 hours.

After the emulsion polymerization, the silicone oil-containing organic resin fine particles of the present invention may be purified and dried from the polymerization mixture by a conventional method, if necessary. Purification may be, for example, ultrafiltration, diafiltration, etc. Drying may be performed, for example, by spray drying, vacuum drying, freeze drying, or the like.

[0018]

As explained above, according to the present invention, a silicone oil-containing organic resin fine particle emulsion having an average particle diameter of 1 μm or less and excellent storage stability and dilution stability can be easily obtained. Further, by drying treatment (spray drying, freeze drying, etc.), a silicone oil-containing organic resin fine particle powder having excellent powder fluidity and storage stability can be obtained. Such powder particles are effective as a material for introducing silicone oil into powders such as powder coatings without impairing powder fluidity, electrical properties, etc.

[0019]

[Examples] The present invention will be specifically explained below with reference to Examples. In addition, unless otherwise specified, "parts" represent parts by weight. Preparation of silicone oil emulsion Preparation Example 1 In a 2-liter glass reaction vessel equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet, 5.14 parts of dodecylbenzenesulfonic acid and 488 parts of deionized water were added. In addition, the temperature was raised to 95±2°C. Here, 250 parts of octamethylcyclotetrasiloxane, 7.20 parts of hexamethyldisiloxane, which were treated with a high-speed homomixer,
A crude emulsion of 5.14 parts of Perex SSL (anionic surfactant manufactured by Kao Corporation; non-volatile content 50%) and 284 parts of deionized water was added dropwise over 3 hours, and an aging treatment was further performed at the same temperature for 5 hours. After the reaction was completed, the mixture was cooled and neutralized by adding a 2N aqueous sodium carbonate solution. As a result, a good seed emulsion having an average particle diameter of 0.204 μm and a silicone oil viscosity of 37.2 centipoise was obtained.

Preparation Example 2 In a 2-liter glass reaction vessel equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet, 300 parts of octamethylcyclotetrasiloxane, 1.6 parts of hexamethyldisiloxane, A crude emulsion of 4.5 parts of dodecyl sulfonic acid and 900 parts of deionized water was prepared and the mixture was heated to 90±2
The reaction was carried out at ℃ for 5 hours. After the reaction was completed, the mixture was cooled and neutralized by adding a 2N aqueous sodium carbonate solution. As a result, a seed emulsion having an average particle diameter of 0.054 μm and a silicone oil viscosity of 1010 centipoise was obtained.

Preparation Example 3 560 parts of deionized water, 10 parts of distearyldimethylammonium chloride, 400 parts of octamethylcyclotetrasiloxane and 12.3 parts of hexamethyldisiloxane were added to a 2-liter beaker and mixed uniformly. This was passed once through a Gaulin homogenizer at a pressure of 600 kg/cm2 to obtain a crude emulsion. Next, 8 liters of deionized water was placed in a 5 liter cylindrical glass reaction vessel equipped with a stirrer, thermometer, reflux condenser and nitrogen gas inlet.
70 parts and 10 parts of stearyltrimethylammonium hydroxide were added and dissolved, and the liquid temperature was maintained at 85±2° C. with slow stirring. The crude emulsion prepared earlier was gradually dropped therein over 2 hours. Aging was further performed at the same temperature for 4 hours. After that, cool it down and
Neutralization treatment was performed with normal phosphoric acid. As a result, the average particle size is 0.
．． A seed emulsion with a silicone oil viscosity of 42 centipoise was obtained.

Preparation Example 4 In a stainless steel beaker, add 40% fatty acid-modified silicone oil (product name KF-910; melting point 45°C) manufactured by Shin-Etsu Chemical Co., Ltd.
Department, polyether-modified silicone oil manufactured by Shin-Etsu Chemical Co., Ltd. (
Product name KF-945), 50 parts of dimethyl silicone oil manufactured by Shin-Etsu Chemical Co., Ltd. (product name KF-96 100CS), nonionic surfactant manufactured by Nippon Nyuka Co., Ltd. (product name NEWC)
OL-714) and 5 parts of anionic surfactant Perex SSL (non-volatile content 50%) manufactured by Kao Corporation were separated.
The mixture was melted at 60° C. in an oil bath and mixed well. 300 parts of deionized water was gradually added to the mixture while stirring to obtain a crude emulsion with a cloudy appearance. This rough emulsion was heated to 800k using a Gaulin homogenizer.
When treated three times at a pressure of g/cm2, the average particle size was 0.
．． A seed emulsion of 525 μm was obtained.

Production Example 1 of Organic Resin Fine Particles Containing Silicone Oil Silicone oil emulsion 37 obtained in Preparation Example 1
2 parts, 200 parts of methyl methacrylate, 6.0 parts of t-dodecanethiol, and deionized water were crudely emulsified by high-speed homomixer treatment. Next, this crude emulsion was charged into a 1-liter glass reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas inlet, and the temperature was raised to 80±2° C. under nitrogen supply conditions. An aqueous solution of 1.0 part of potassium persulfate dissolved in 200 parts of deionized water was added dropwise thereto over 1 hour, followed by further aging at the same temperature for 3 hours. As a result, a good silicone oil-containing organic resin fine particle emulsion having an average particle diameter of 0.273 microns was obtained.

Next, the silicone oil-containing organic resin fine particle emulsion obtained above is subjected to emulsion purification by ultrafiltration, and then dried using a spray dryer to obtain dry silicone oil-containing organic resin fine particles in the form of a powder with excellent powder fluidity. was gotten.

When the dried fine particles of the organic resin containing silicone oil thus obtained were subjected to a blocking test for 96 hours in an oven at 40°C, no change in powder fluidity was observed. Additionally, the thermal properties of the dried resin fine particle powder were measured. The results are shown in Table-1.

Example 2 Silicone oil emulsion 78 obtained in Preparation Example 2
8 parts, 100 parts of styrene, 94 parts of butyl acrylate,
6.0 parts of t-dodecanethiol and deionized water were processed into a crude emulsion using a high-speed homomixer. Next, this crude emulsion was charged into a 1-liter glass reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas inlet, and the temperature was raised to 80±2° C. under nitrogen supply conditions. Add 1.0 part of potassium persulfate to 2 parts of deionized water.
An aqueous solution of 0.00 parts was added dropwise over 1 hour, and the mixture was further aged at the same temperature for 5 hours. As a result, a good silicone oil-containing organic resin fine particle emulsion having an average particle diameter of 0.098 microns was obtained. Thereafter, the silicone oil-containing organic resin fine particles were purified and dried in the same manner as in Example 1, and the thermal properties of the fine particles were tested. The results are shown in Table-1.

Example 3 Silicone oil emulsion obtained in Preparation Example 3 50
1 part, V-50 (Wako Pure Chemical's cationic azo-based initiation catalyst)
0.55 parts and 284 parts of deionized water were charged into a 1-liter glass reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas inlet, and the mixture was heated for 70 minutes under nitrogen gas supply conditions.
The temperature was raised to ±2°C. A mixed solution of 94.2 parts of styrene, 49.5 parts of butyl methacrylate, 4.36 parts of hydroxyethyl methacrylate and 1.98 parts of 2-ethylhexylthioglycolate was added dropwise thereto over 1 hour.
Furthermore, aging treatment was performed at the same temperature for 3 hours. As a result, a good silicone oil-containing organic resin fine particle emulsion having an average particle diameter of 0.163 microns was obtained. Thereafter, the silicone oil-containing organic resin fine particles were purified and dried in the same manner as in Example 1, and the thermal properties of the fine particles were tested. The results are shown in Table-1.

Example 4 Silicone oil emulsion 20 obtained in Preparation Example 4
0 parts, 290 parts of styrene, 150 parts of butyl acrylate, 10 parts of α-methylstyrene dimer, 3 parts of dodecylbenzenesulfonic acid sodium salt, 2.4 parts of potassium persulfate.
1 part and 450 parts of deionized water were processed into a crude emulsion by high-speed homomixer treatment. Furthermore, deionized water 900
After adding 50% of the mixture, the mixture was charged into a 3-liter glass reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas inlet, and the reaction temperature was 84±2°C under nitrogen supply conditions. Polymerization was carried out for 6 hours at a lower temperature. As a result, a cloudy white emulsion of silicone oil-containing organic resin fine particles having an average particle diameter of 0.782 was obtained.

[0029]

[Table 1]

Claims (8)

[Claims] [Claim 1] The organic resin fine particles have a general formula: ;
Cycloalkyl group; alkoxy group; alkenyl group; phenyl group; represents a monovalent hydrocarbon group; a polyoxyalkylene group; a vinyl polymer residue; or a fatty acid ester group,
m represents a number such that the molecular weight of the siloxane skeleton is 1,000,000 or less. ] Silicone oil 5 to 70
% by weight, and the particle surface layer contains 30 to 95 weight % of a thermoplastic resin with a glass transition temperature of 30 to 200°C prepared from an ethylenically unsaturated monomer, and an average particle diameter of 0.0
Silicone oil-containing organic resin fine particles having a particle size of 5 to 1 μm. Claim 2: The siloxane skeleton has a molecular weight of 400 to 1.
The silicone oil-containing organic resin fine particles according to claim 1, wherein the silicone oil-containing organic resin fine particles have a molecular weight of 0.00,000. 3. The silicone oil-containing organic resin fine particles according to claim 1 or 2, wherein the silicone oil is liquid at 100° C. or lower. 4. Claims 1 to 3, wherein the thermoplastic resin has a glass transition temperature of 50 to 200°C.
The silicone oil-containing organic fine particles according to any one of the above. [Claim 5] The thermoplastic resin has an average molecular weight of 1.0.
00,000 or less.
4. The silicone oil-containing organic fine particles according to any one of 4. 6. The ethylenically unsaturated monomer is a vinyl monomer, (meth)acrylamide monomer, (meth)
The silicone oil-containing organic resin fine particles according to any one of claims 1 to 5, characterized in that the particles are selected from the group consisting of acrylate monomers, unsaturated monomers, and dicarboxylic acid monomers. 7. The silicone according to claim 1, wherein the ethylenically unsaturated monomer is added to an emulsion of the silicone oil in which the micelles have an average particle size of 1 μm or less and emulsion polymerization is carried out. A method for producing oil-containing organic resin particles. 8. The method for producing silicone oil-containing organic resin fine particles according to claim 7, wherein the degree of polymerization of the thermoplastic resin is further adjusted by using an allyl monomer, a mercapto monomer, or both.