JPH07196802A - Production of fluid dispersion of diorganopolysiloxane with high degree of polymerization - Google Patents

Abstract

PURPOSE:To obtain a fluid dispersion of a diorganopolysiloxane with a degree of polymn. of 3,000 or higher efficiently in a short time by condensing a silanolterminated diorganopolysiloxane with a specific diaminosilane in the presence of a specific terminal-blocking agent. CONSTITUTION:A silanol-terminated diorganopolysiloxane of the formula: HO (R<1>2SiO)nH (wherein R<1> is a 1-8C monovalent hydrocarbon group; and n is an integer of 2-1,000) is condensed with a diaminosilane of the formula: R<2>2Si(NR<3>2)2 (wherein R<2> and R<3> are each a 1-8C monovalent hydrocarbon group) or its partial hydrolyzate or their mixture in a molar ratio of the NR<3>2 group of the latter reactant to the silanol group of the former of 0.5-5 in the presence of a terminal-blocking agent comprising a silanol of the formula: R<4>3SiOH (wherein R<4> is a 1-8C hydrocarbon group) or an aminosilane of the formula: R<4>3SiNR<3>2 (wherein R<3> and R<4> are each a 1-8C hydrocarbon group) or a disilazane of the formula: (R<4>3Si)2NH (wherein R<4> is a 1-8C hydrocarbon group).

Description

Detailed Description of the Invention

[0001]

The present invention relates to a cosmetic raw material, a release agent,
The present invention relates to a method for producing a high polymerization degree organopolysiloxane dispersion liquid which is useful as a material for coating agents and the like.

[0002]

2. Description of the Related Art Dispersions of high degree of polymerization diorganopolysiloxane have been conventionally used as cosmetic raw materials, mold release agents, coating agents and the like. Usually, the high degree of polymerization diorganopolysiloxane having a degree of polymerization of 3,000 or more is in the form of a gum, and the dispersion is prepared by adding the high degree of polymerization diorganopolysiloxane in the form of gum to a volatile organic solvent or a volatile liquid diorganopolysiloxane. Although it is produced by dispersing it in the solution, it is necessary to stir for a long time (usually about 10 hours or more) in order to obtain a uniform dispersion. Therefore, since such a manufacturing method is not efficient, it is desired to improve productivity.

[0003]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a method for efficiently producing a dispersion of a high degree of polymerization diorganopolysiloxane having a degree of polymerization of 3000 or more in a short time.

[0004]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that when a terminal silanol group-terminated diorganopolysiloxane, a specific diaminosilane and a specific terminal blocking agent are condensed in a volatile solvent, The present invention has been completed by finding that the degree of polymerization of diorganopolysiloxane is obtained in a state of being dispersed in the solvent.

In the present invention, in a volatile solvent, (A) the following general formula (1): HO [(R ¹ ) ₂ SiO] _n H (1) (In the formula, a plurality of R ^1's may be the same or different. May also be a substituted or unsubstituted monovalent hydrocarbon group having 1 to 8 carbon atoms,
n is an integer of 2 to 1000. ) A terminal silanol group-terminated diorganopolysiloxane, and (B) the following general formula (2): (R ² ) ₂ Si [N (R ³ ) ₂ ] ₂ (2) (wherein a plurality of R ² may be the same or different and is a substituted or unsubstituted monovalent hydrocarbon group having 1 to 8 carbon atoms,
A plurality of R ^{3 s} may be the same or different and have 1 to 3 carbon atoms.
8 is a monovalent hydrocarbon group. ) Diaminosilane represented by the formula, a partial hydrolysis product thereof, or a mixture thereof,
(C) The following general formula (3): (C) is an amount such that 0.5 mol of the —N (R ³ ) ₂ group contained in the general formula (2) is 0.5 to 5 mol of the silanol group of the component (A). Silanol represented by R ⁴ ) ₃ SiOH (3) (in the formula, plural R ^{4 s} may be the same or different and each is a substituted or unsubstituted monovalent hydrocarbon group having 1 to 8 carbon atoms). The following general formula (4): (R ⁴ ) ₃ Si N (R ³ ) ₂ (4) (In the formula, a plurality of R ⁴ may be the same or different, and as described above, a plurality of R ³ are the same. However, it may be different as described above.), And an aminosilane represented by the following general formula (5): [(R ⁴ ) ₃ Si] ₂ NH (5) (in the formula, plural R ⁴ may be the same or different. It may be different as described above.) The polymerization in the presence of at least one end-capping agent selected from the group consisting of disilazanes represented by Higher than 3000 degrees Provided is a method for producing a dispersion of a high degree of polymerization diorganopolysiloxane, which comprises producing a degree diorganopolysiloxane.

(A) Terminal silanol group terminated diorganopoly
The terminal silanol group-terminated diorganopolysiloxane (A) of the siloxane (A) component is represented by the above general formula (1). The above general formula
R ^{1 in} (1) is specifically, for example, an alkyl group such as a methyl group, an ethyl group or a propyl group; for example, a vinyl group,
An alkenyl group such as an allyl group; for example, an aryl group such as a phenyl group and a tolyl group; a chloromethyl group obtained by substituting a part or all of hydrogen atoms of these groups with a substituent such as a halogen atom and a cyano group, Examples include groups such as 3,3,3-trifluoropropyl group and 2-cyanoethyl group.

The viscosity of the above silanol-terminated diorganopolysiloxane at 25 ° C. is usually 5 to 10
It is 0,000 cSt.

The component (B) diaminosilane (B) reacts with the silanol group of the component (A) —N (R
³ ) A diaminosilane represented by the above general formula (2) having two ₂ groups and / or a partial hydrolysis product thereof, for increasing the degree of polymerization of the obtained diorganopolysiloxane. The component (B) has an advantage that it can be easily removed to the outside of the reaction system because NH (R ³ ) _{2 and the} like produced as a by-product of condensation with the silanol group of the component (A) are volatile.

Specific examples of R ² and R ³ in the general formula (2) include the groups exemplified as R ¹ in the general formula (1).

Examples of the diaminosilane represented by the above general formula (2) include dimethylbis (dimethylamino) silane, dimethylbis (diethylamino) silane, dimethylbis (di-n-butylamino) silane, methylvinylbis ( Examples thereof include dimethylamino) silane, methylvinylbis (diethylamino) silane, methylvinylbis (di-n-butylamino) silane, and methyltrifluoropropylbis (diethylamino) silane. Preferred among these are dimethylbis (dimethylamino) silane, dimethylbis (diethylamino) silane, methylvinylbis (dimethylamino) silane and methylvinylbis (diethylamino) silane.

Further, the partial hydrolysis product of diaminosilane represented by the above general formula (2) is, for example, the following general formula (8)
: (R ² ) ₂ [N (R ³ ) ₂ ] SiO- [(R ³ ) ₂ SiO] _s -Si [N (R ³ ) ₂ ] (R ² ) ₂ (8) (wherein a plurality of R ² may be the same or different as described above, plural R ³ may be the same or different as described above, and s is an integer of 0 or more, preferably an integer of 1 to 100. It is represented by).

Among the above-mentioned components (B), preferred ones are
It is a partial hydrolysis product of dimethylbis (dimethylamino) silane, dimethylbis (diethylamino) silane, methylvinylbis (dimethylamino) silane and methylvinylbis (diethylamino) silane.

The amount of the component (B) used is such that the amount of the --N (R ³ ) ₂ group is 0.5 to 5 mol, preferably 0.8 to 3.0 mol, per 1 mol of the silanol group of the component (A). Is the amount. When the amount of the component (B) used is such that the amount of -N (R ³ ) ₂ groups is less than 0.5 mol per 1 mol of the silanol group of the component (A), the high degree of polymerization diorganopolysiloxane having a degree of polymerization of 3000 or more is When the amount of the -N (R ³ ) ₂ group exceeds 5 mol, it becomes difficult to stably produce a high degree of polymerization diorganopolysiloxane, and it is economically disadvantageous.

(C) Terminal Blocking Agent The terminal blocking agent of the component (C) is for controlling the molecular weight of the high degree of polymerization diorganopolysiloxane obtained by condensation, and as the component (C), the above-mentioned general At least one selected from the group consisting of silanol represented by the formula (3), aminosilane represented by the general formula (4) and disilazane represented by the general formula (5) is used.

As R ⁴ in the above general formulas (3) to (5),
Specific examples include the groups exemplified as R ¹ in the above general formula (1).

Examples of the silanol represented by the above general formula (3) include trimethylsilanol, methyldiphenylsilanol, trivinylsilanol and the like.
Examples of the aminosilane represented by the above general formula (4) include trimethyl (dimethylamino) silane, trimethyl (diethylamino) silane, dimethylvinyl (dimethylamino) silane, dimethylvinyl (diethylamino) silane and the like. Furthermore, the above general formula (5)
Examples of the disilazane represented by: include hexamethyldisilazane, tetramethyldivinyldisilazane, hexavinyldisilazane, and the like.

Volatile Solvent Examples of the volatile solvent used in the above production method include volatile organic solvents and volatile siloxanes.

Specific examples of the volatile organic solvent include aromatic hydrocarbons such as benzene, toluene and xylene; aliphatic hydrocarbons such as pentane, hexane, heptane, octane, nonane and decane; For example,
Ethers such as diethyl ether and dibutyl ether;
For example, ketones such as acetone, methyl ethyl ketone, methyl propyl ketone, and cyclohexanone; examples thereof include heterocyclic compounds such as tetrahydrofuran, among which aromatic hydrocarbons such as toluene and xylene; and aliphatic hydrocarbons such as hexane and octane. Hydrocarbons are preferred.

The volatile siloxane is cyclic, linear,
It may have any branched structure. Examples of the cyclic volatile siloxane include, for example, the following general formula (6): [(R ⁵ ) ₂ SiO] _p (6) (In the formula, a plurality of R ^{5 s} may be the same or different and may be a hydrogen atom or a carbon atom. A hydrocarbon group of formula 1 to 8, for example, an alkyl group, an alkenyl group or an aryl group, and p is 3
It is an integer from ~ 15. ).

Examples of the hydrocarbon group having 1 to 8 carbon atoms represented by R ⁵ in the general formula (6) include those exemplified for R ¹ , preferably an alkyl group, and more preferably an alkyl group. It is a methyl group. Suitable cyclic siloxanes are
Octamethylcyclotetrasiloxane and decamethylcyclopentasiloxane.

Examples of the linear volatile siloxane include, for example, the following general formula (7): (R ⁶ ) ₃ Si [(R ⁵ ) ₂ SiO] _q Si (R ⁶ ) ₃ (7) R ^{6 s} may be the same or different and each is a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, such as an alkyl group, an alkenyl group or an aryl group, and q is an integer of 1 to 13. , A plurality of R ^{5 s} may be the same or different and are as described above.

R ⁶ in the above general formula (7) is preferably
It is an alkyl group, more preferably a methyl group. Suitable linear siloxanes are hexamethyldisiloxane and octamethyltetrasiloxane.

Further, as the branched volatile siloxane,
For example, a siloxane in which an alkylsiloxy group is introduced into the side chain of the above linear volatile siloxane can be mentioned, and specifically, for example, tris (trimethylsiloxy)
Examples include methylsilane and tetra (trimethylsiloxy) silane.

Reaction Conditions The reaction of the above components (A) to (C) in the above volatile solvent is usually carried out at 100 to 200 ° C., and the polymerization degree is usually 3000 or more and the high polymerization degree is 3000 or more in 0.5 to 3 hours. A diorganopolysiloxane is produced.

The degree of polymerization of the high degree of polymerization diorganopolysiloxane is 30 in that the resulting dispersion exhibits good fluidity.
00 to 20000 is preferable, and 5000 to 12000 is more preferable.
Further, the high polymerization degree diorganopolysiloxane produced is
It is in a state of being dispersed in the volatile solvent. That is, at the same time as the formation of the diorganopolysiloxane, the desired dispersion of the high degree of polymerization diorganopolysiloxane is produced.

The concentration of the component (A) in the volatile solvent in the condensation reaction is not particularly limited and is usually in the range of 5 to 90% by weight.

Since condensation by-products such as dialkylamines produced by the above condensation are volatile, they can be easily removed from the system by stripping under reduced pressure or by blowing in steam.

[0028]

EXAMPLES The present invention will be specifically described below with reference to examples. Example 1 A 1 L flask was charged with 700 g of octamethylcyclotetrasiloxane, 300 g of silanol group-terminated dimethylpolysiloxane having silanol groups at both ends having a viscosity of 5000 cSt at 25 ° C., and 0.1 g of trimethylsilanol, and they were uniformly mixed. Then, add dimethylbis (dimethylamino) to the flask.
After adding 2.3 g of silane and stirring at room temperature for 10 minutes, the temperature in the flask was raised to 150 ° C. and the reaction was carried out at 150 ° C. for 1 hour. The dispersion thus obtained was a colorless and transparent liquid having a viscosity at 25 ° C. of 39000 cSt.

The dispersion was analyzed by gel permeation chromatography to find that the weight average molecular weight was 486,000.
It was confirmed that a high degree of polymerization dimethylpolysiloxane having a degree of polymerization of 6570 was contained.

The dispersion was stripped under the conditions of 150 ° C. and 10 mmHg and analyzed for volatile matter. As a result, the dispersion contained 71% by weight of octamethylcyclotetrasiloxane. It was confirmed. Therefore,
It was found that the octamethylcyclotetrasiloxane was unreacted.

Example 2 A 1 L flask was charged with 850 g of octamethylcyclotetrasiloxane and 150 g of dimethylpolysiloxane terminated with silanol groups at both ends and having a viscosity of 700 cSt at 25 ° C., and mixed uniformly. Subsequently, 2.5 g of dimethylbis (dimethylamino) silane and trimethyl were added to the flask.
(Dimethylamino) silane 0.2g was added at room temperature for 10
After stirring for 1 minute, the temperature in the flask was raised to 150 ° C and the reaction was carried out at 150 ° C for 1 hour. The thus obtained dispersion liquid was a colorless and transparent liquid having a viscosity at 25 ° C. of 4200 cSt.

The dispersion was analyzed by gel permeation chromatography to find that the weight average molecular weight was 448,000.
It was confirmed that a high degree of polymerization dimethylpolysiloxane having a degree of polymerization of 6050 was contained.

The dispersion was stripped under the conditions of 150 ° C. and 10 mmHg and analyzed for volatile matter. As a result, the dispersion contained 86% by weight of octamethylcyclotetrasiloxane. It was confirmed. Therefore,
It was found that the octamethylcyclotetrasiloxane was unreacted.

Example 3 In a 1 L flask, 850 g of toluene and a viscosity of 1200 cSt at 25 ° C. and 5 units of diphenylcyclosiloxane were added.
150 g of dimethyldiphenylpolysiloxane terminated with silanol groups at both ends containing mol% was charged and uniformly mixed. Subsequently, 3.5 g of dimethylbis (diethylamino) silane and 0.3 g of trimethyl (diethylamino) silane were added to the flask and stirred at room temperature for 10 minutes,
The temperature in the slasco was raised to 150 ° C, and the reaction was carried out at 150 ° C for 1 hour. The dispersion thus obtained has a temperature of 25 ° C.
It was a colorless transparent liquid having a viscosity of 5500 cSt.

As a result of analyzing this dispersion by gel permeation chromatography, it was confirmed that it contained a highly polymerized dimethyldiphenylpolysiloxane having a weight average molecular weight of 43500 (polymerization degree of 5400) (volatile content: 84%). .

The dispersion was stripped under the conditions of 150 ° C. and 10 mmHg, and the volatile content was analyzed. As a result, it was confirmed that the dispersion contained 84% by weight of the volatile content. It was

[0037]

According to the production method of the present invention, the degree of polymerization is 3000
Since the dispersion liquid of the above-mentioned high degree of polymerization diorganopolysiloxane can be efficiently produced in a short time, the productivity is improved.

Claims (1)

[Claims] 1. In a volatile solvent, (A) the following general formula (1): HO [(R ¹ ) ₂ SiO] _n H (1) (In the formula, plural R ¹ may be the same or different. A substituted or unsubstituted monovalent hydrocarbon group having 1 to 8 carbon atoms,
n is an integer of 2 to 1000. ) A terminal silanol group-terminated diorganopolysiloxane, and (B) the following general formula (2): (R ² ) ₂ Si [N (R ³ ) ₂ ] ₂ (2) (wherein a plurality of R ² may be the same or different and is a substituted or unsubstituted monovalent hydrocarbon group having 1 to 8 carbon atoms,
A plurality of R ^{3 s} may be the same or different and have 1 to 3 carbon atoms.
8 is a monovalent hydrocarbon group. ) Diaminosilane represented by the formula, a partial hydrolysis product thereof, or a mixture thereof,
(C) The following general formula (3): (C) is an amount such that 0.5 mol of the —N (R ³ ) ₂ group contained in the general formula (2) is 0.5 to 5 mol of the silanol group of the component (A). Silanol represented by R ⁴ ) ₃ SiOH (3) (in the formula, plural R ^{4 s} may be the same or different and each is a substituted or unsubstituted monovalent hydrocarbon group having 1 to 8 carbon atoms). The following general formula (4): (R ⁴ ) ₃ Si N (R ³ ) ₂ (4) (In the formula, a plurality of R ⁴ may be the same or different, and as described above, a plurality of R ³ are the same. However, it may be different as described above.), And an aminosilane represented by the following general formula (5): [(R ⁴ ) ₃ Si] ₂ NH (5) (in the formula, plural R ⁴ may be the same or different. It may be different as described above.) The polymerization in the presence of at least one end-capping agent selected from the group consisting of disilazanes represented by Higher than 3000 degrees A method for producing a dispersion of a high degree of polymerization diorganopolysiloxane, which comprises producing a degree diorganopolysiloxane.