JP2003252995A - Method for manufacturing polyorganosiloxane, and liquid silicone rubber containing polyorganosiloxane - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique for manufacturing a polyorganosiloxane of a narrow molecular weight distribution having both ends modified in a more effective, more economical and highly safe method, and a liquid silicone rubber which has been deprived of (or which contains) a low-molecular weight cyclic siloxane to an extent that silicone troubles are not caused. <P>SOLUTION: The method for manufacturing a polyorganosiloxane comprises subjecting at least one cyclic siloxane represented by formula (1) (wherein R<SP>1</SP>and R<SP>2</SP>are each independently a 1-20C alkyl group, a 6-10C aryl group, a vinyl group, a trifluoropropyl group or hydrogen; and p is an integer of 3-10) to a polymerization reaction in the presence of a lithium-containing polymerization catalyst in a solvent containing water and subsequently terminating the polymerization reaction using a chlorosilane represented by formula (2) (wherein R<SP>3</SP>and R<SP>4</SP>are each independently a 1-20C alkyl group or a 6-10C aryl group; and X is a 2-20C alkenyl group, a styryl group, a methacryloyloxypropyl group or an acryloyloxypropyl group). <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a polyorganosiloxane and a liquid silicone rubber containing the polyorganosiloxane.

[0002]

Both end-modified polyorganosiloxanes are
It is produced by anionic (living) polymerizing a cyclic siloxane using water as an initiator in the presence of a lithium-based catalyst using one or a mixture of two or more polar solvents having no active hydrogen such as tetrahydrofuran. (For example, refer to Patent Document 1.). However, when the conversion of the cyclic siloxane exceeds 95 mol% (hereinafter, “mol%” is simply referred to as “%” for the conversion), the molecular weight distribution of the both-end-modified polyorganosiloxane obtained becomes wide. In order to obtain a polyorganosiloxane modified at both ends with a narrow molecular weight distribution, the conversion rate of the cyclic siloxane is 9
The polymerization reaction had to be stopped before reaching 5%. Further, since a polar solvent is used in the polymerization reaction, a large amount of waste water containing an organic solvent is generated in the water washing step. Therefore, the method for producing a polyorganosiloxane modified at both ends with a narrow molecular weight distribution is not always an efficient and economical production method. Further, since polar solvents such as tetrahydrofuran and 1,4-dioxane used as a polymerization reaction solvent are highly explosive, attention (care) is required in terms of safety. Therefore, a technique for producing a polyorganosiloxane modified at both ends with a narrow molecular weight distribution by a more efficient, more economical and highly safe method is desired.

On the other hand, liquid silicone rubbers and silicone modified resins used as materials for electric parts and electronic parts are manufactured by an equilibrium reaction method or a cohydrolysis method. However, low molecular cyclic siloxanes (D _{3 to} D) that are by-produced in the liquid silicone rubber obtained by these methods.
₍ Expressed as ₁₀ components) is contained in the order of 10 and several weight%. Therefore, when these liquid silicone rubbers are used as materials for electrical parts and electronic parts, low molecular weight cyclic siloxane burns on electrical contacts or polymerizes and adheres to the contacts, resulting in poor conduction or contact wear. Cause trouble. This silicone trouble can be prevented in many cases by using a liquid silicone rubber or the like made of polyorganosiloxane having a total amount of D _{3 to} D ₁₀ components of 500 ppm or less (for example, See Patent Document 1.). The low-molecular cyclic siloxane is removed by distillation so as not to cause this silicone trouble. However, the removal of the low-molecular cyclic siloxane is insufficient with the polyorganosiloxane distilled and purified by the conventional technique, and the high-temperature, high vacuum It is not practical because it is necessary to subject it to thin film evaporation. Therefore, low molecular cyclic siloxane was removed to the extent that it does not cause silicone trouble (only included)
Liquid silicone rubber and the like are strongly desired as materials for electric parts and electronic parts.

[Patent Document 1] JP-A-1-272633

[Non-Patent Document 1] Silicone Handbook, Nikkan Kogyo Shimbun, August 1990, 396 pages.

[0004]

DISCLOSURE OF THE INVENTION An object of the present invention is to provide a technique for producing a polyorganosiloxane modified at both ends with a narrow molecular weight distribution by a more efficient, more economical and highly safe method and a low molecular weight compound. It is to provide a liquid silicone rubber in which the cyclic siloxane has been removed (contained only) to the extent that it does not cause silicone troubles.

[0005]

SUMMARY OF THE INVENTION In view of the above-mentioned problems of the prior art, the present inventors have conducted extensive research. As a result, a method for producing a polyorganosiloxane in which at least one cyclic siloxane is polymerized in the presence of a lithium-based polymerization catalyst in a solvent containing water and then the polymerization reaction is terminated by using chlorosilane If so, the amount of cyclic siloxane 3- to 10-mer (D _{3 to} D ₁₀ ) having a low vapor pressure, which is usually generated in the polymerization reaction of the cyclic siloxane, is small, so that the polymerization reaction liquid is heated at high temperature under high vacuum. It has been found that it is possible to easily reduce the content ratio of the cyclic siloxane contained in the polymerization reaction liquid by distillation with a solvent cut level without subjecting it to evaporation or the like.

Furthermore, in the above-mentioned production method, it was found that the molecular weight and viscosity of the obtained polyorganosiloxane can be controlled by controlling the amount of cyclic siloxane and the amount of water in the solvent, and the present invention was completed. Let

The present invention has the following configuration. (1) A chlorosilane represented by the following formula (2) after polymerizing at least one cyclic siloxane represented by the following formula (1) in the presence of a lithium-based polymerization catalyst in a solvent containing water. A method for producing a polyorganosiloxane, characterized in that the polymerization reaction is stopped by using. (In the formula, R ¹ and R ² are each independently an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 10 carbon atoms, a vinyl group, a trifluoropropyl group or hydrogen, and p is 3 to 10
Is an integer. ) (In the formula, R ³ and R ⁴ are each independently an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 10 carbon atoms, and X is an alkenyl group having 2 to 20 carbon atoms, a styryl group, or methacryloxypropyl. Group or acryloxypropyl group.)

(2) The method for producing a polyorganosiloxane according to the above item 1, wherein the solvent is a mixed solvent of a nonpolar solvent and a polar solvent. (3) Item 1 or 2 above, wherein the proportion of the lithium-based polymerization catalyst is in the range of 0.001 to 1 mol with respect to 1 mol of water.
6. A method for producing a polyorganosiloxane according to the item.

(4) The molecular weight and viscosity of the resulting polyorganosiloxane are controlled by controlling the amount of cyclic siloxane and the amount of water in the solvent. The method for producing a polyorganosiloxane according to claim 1.

(5) In the chlorosilane represented by the formula (2) described in the above item 1, X is an alkenyl group having 2 to 20 carbon atoms, and both terminals alkenyl group modification described in any one of the above items 1 to 4 A method for producing a polyorganosiloxane.

(6) Production of a polyorganosiloxane modified with vinyl groups at both ends according to any one of the above items 1 to 4, wherein the polymerization reaction is terminated using chlorosilane represented by the following formula (3). Method.

(7) A polyorganosiloxane modified with methacrylpropyl groups at both ends according to any one of the above items 1 to 4, wherein the chlorosilane represented by the following formula (4) is used to terminate the polymerization reaction. Production method.

(8) A chlorosilane represented by the following formula (5) is used to terminate the polymerization reaction, and the polyorganosiloxane modified with an acrylic propyl group at both ends according to any one of items 1 to 4 above Production method.

(9) At least one polyorganosiloxane (A) selected from the polyorganosiloxanes produced by the production method according to any one of items 1 to 8 and SiH groups in one molecule. A one-component or two-component liquid silicone rubber containing at least two organohydrogenpolysiloxanes (B) and a platinum catalyst (C).

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.
The production method of the present invention comprises anionic living polymerization of a monomeric cyclic siloxane represented by the above formula (1) in a solvent containing water in the presence of a lithium-based catalyst. At that time, the chlorosilane represented by the above formula (2) is used as a polymerization terminator. The polyorganosiloxane obtained by the production method of the present invention is a polyorganosiloxane modified at both ends with a narrow molecular weight distribution, and has a low content of unreacted low molecular weight siloxane.

In the above formula (1) which is a monomer, R
¹ and R ² are each independently an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 10 carbon atoms, a vinyl group, a trifluoropropyl group or hydrogen. Of these, carbon number 1
As the alkyl group of ˜20, even a straight-chain alkyl group,
It may be a branched chain, but is preferably a linear alkyl group. Specific examples of the alkyl group having 1 to 20 carbon atoms include methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, s-butyl group,
Examples thereof include t-butyl group, pentyl group, neopentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, cyclopentyl group and cyclohexyl group.

Examples of the aryl group having 6 to 10 carbon atoms include phenyl group, toluyl group, xylyl group and ethylphenyl group. As other R ¹ and R ² , a vinyl group or hydrogen is effective for increasing the degree of crosslinking of the liquid silicone rubber, and a trifluoropropyl group is effective for increasing the solvent resistance.

Of these, R ¹ and R ² are preferably methyl, ethyl, phenyl, vinyl or hydrogen because of easy availability of raw materials. From the viewpoints of economy and ease of handling, R ¹ and R ² are particularly preferably methyl groups.

Examples of the cyclic siloxane represented by the formula (1) which is a monomer include cyclic trisiloxane (p is 3), cyclic tetrasiloxane (p is 4), cyclic pentasiloxane (p is 5) and the like. Is mentioned. Of these, specific examples of the cyclic trisiloxane include 1,1,
3,3,5,5-hexamethylcyclotrisiloxane,
1,1,3,3,5,5-hexaethylcyclotrisiloxane, 1,3,5-trimethyl-1,3,5-triethylcyclotrisiloxane, 1,3,5-trimethyl-
1,3,5-triisopropylcyclotrisiloxane,
1,1,3,3,5,5-hexaphenylcyclotrisiloxane, 1,3,5-trimethyl-1,3,5-triphenylcyclotrisiloxane, 1,3,5-trimethyl-1,3 5-trivinylcyclotrisiloxane,
1,1,3,3,5,5-hexavinylcyclotrisiloxane, 1,3,5, -trimethyl-1,3,5-
(3,3,3-Trifluoropropyl) cyclotrisiloxane, 1,3,5-trimethyl-1,3,5-trihydrocyclotrisiloxane, and 1,3,5-triphenyl-1,3,5 -Trihydrocyclotrisiloxane and the like, and at least one or more of them are used in the present invention.

In the above formula (2) which is a polymerization terminator,
R ³ and R ⁴ are each an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 10 carbon atoms, and X has 2 to 2 carbon atoms.
0 is an alkenyl group, a styryl group, a methacryloxypropyl group or an acryloxypropyl group. this house,
The alkyl group having 1 to 20 carbon atoms may be linear or branched, but is preferably a linear alkyl group. Specific examples of the alkyl group having 1 to 20 carbon atoms include methyl group, ethyl group, n-propyl group,
i-propyl group, n-butyl group, i-butyl group, s-butyl group, t-butyl group, pentyl group, neopentyl group,
Hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, cyclopentyl group,
Examples thereof include a cyclohexyl group. The aryl group having 6 to 10 carbon atoms includes phenyl group, toluyl group, xylyl group, ethylphenyl group and the like.

Examples of the alkenyl group having 2 to 20 carbon atoms in X include vinyl group, allyl group, butenyl group, pentenyl group, hexenyl group, octenyl group and undecenyl group.

Among these, R is easy to obtain because of its availability.
³ , R ⁴ is preferably a methyl group or a phenyl group, and X is preferably a vinyl group, a styryl group, a methacryloxypropyl group or an acryloxypropyl group. From the viewpoints of economy and ease of handling, it is particularly preferable that R ³ and R ⁴ are methyl groups, and X is a vinyl group or a methacryloxypropyl group.

Specific examples of the chlorosilane represented by the formula (2) which is a polymerization terminator include vinyldimethylchlorosilane, vinylphenylmethylchlorosilane, vinyldiphenylchlorosilane, allyldimethylchlorosilane, 3-butenyldimethylchlorosilane and 4-pentenyldimethylchlorosilane. , 5-hexenyldimethylchlorosilane, 7-
Octenyldimethylchlorosilane, 10-undecenyldimethylchlorosilane, styryldimethylchlorosilane, 3-methacryloxypropyldimethylchlorosilane, and 3-acryloxypropyldimethylchlorosilane. As the chlorosilane represented by the formula (2) which is a polymerization terminator, Is preferred. Furthermore, vinyldimethylchlorosilane,
3-methacryloxypropyldimethylchlorosilane and 3-acryloxypropyldimethylchlorosilane are particularly preferred.

The polymerization reaction in the production method of the present invention is carried out in a solvent containing water. The solvent used is not particularly limited. Specific examples thereof include nonpolar solvents such as toluene, xylene, n-hexane and cyclohexane, and polar solvents such as dimethylformamide, dimethylacetamide, tetrahydrofuran, dimethylsulfoxide and diglyme. A mixed solvent obtained by mixing these non-polar solvents and polar solvents can also be used.
It is preferable to use a mixed solvent of a non-polar solvent and a polar solvent rather than carrying out the polymerization reaction only with the non-polar solvent, since the reaction rate becomes faster. In addition, the mixed solvent facilitates uniform dissolution of water in the solvent. The mixing ratio of the non-polar solvent and the polar solvent in the mixed solvent is not particularly limited, but a mixed solvent containing a non-polar solvent as a main solvent is preferable. In particular, the ratio of the polar solvent is preferably 1 to 50 parts by weight with respect to 100 parts by weight of the nonpolar solvent.

The amount of water contained in the solvent is not particularly limited, but is the number of moles obtained by dividing the weight of the cyclic siloxane used in the polymerization reaction by the molecular weight of the desired polyorganosiloxane (cyclic siloxane). (Weight / molecular weight of desired polyorganosiloxane). The amount of water is an important factor controlling the molecular weight and viscosity of the polyorganosiloxane,
By varying the amount of water, the molecular weight and viscosity of the polyorganosiloxane obtained can be controlled. The amount of water mentioned above also includes water containing the cyclic siloxane and the solvent in advance. Therefore, the amount of water used for polymerization is
This is the total amount of water previously contained by the cyclic siloxane and the solvent and water to be added later. For the weight of water that the cyclic siloxane and solvent already contain,
It can be obtained by quantitative analysis using a gas chromatograph.

The lithium-based polymerization catalyst used in the production method of the present invention is not particularly limited, and specific examples thereof include alkyllithium, lithium hydroxide and lithium trialkylsilanolate. Examples of the alkyl lithium include n-butyl lithium, s-butyl lithium, t-butyl lithium and methyl lithium. Examples of the lithium trialkylsilanolate include lithium trimethylsilanolate, lithium triethylsilanolate and lithium triisopropylsilanolate. Of these, n-butyllithium and lithium hydroxide can be preferably used in the present invention.

The living anionic polymerization reaction rate in the production method of the present invention can be controlled by changing the ratio of the lithium-based polymerization catalyst to water. In the production method of the present invention, the ratio is not particularly limited, but in order to keep the reaction rate of the polymerization reaction within a suitable range, the ratio of the lithium-based polymerization catalyst to 1 mol of water is 0. It is preferably in the range of 001 to 1, and more preferably in the range of 0.005 to 0.1 in terms of molar ratio. Within this range, the reaction rate will be moderate, so that the conversion of the cyclic siloxane can be easily measured. Therefore, the polymerization reaction can be easily controlled.

In the method for producing a polyorganosiloxane of the present invention, polymerization is initiated by adding a catalyst to a solvent containing a monomer, and when a preset conversion rate is reached, a polymerization terminator is added. The reaction is terminated. More specifically, by adding a lithium-based polymerization catalyst to a mixed solution of a solvent containing water and a cyclic siloxane represented by the above formula (1), an amount of cyclic siloxane corresponding to the amount of water can be increased. Open the ring. Then, the ring-opened siloxane serves as an initiator and consumes the cyclic siloxane to perform living anionic polymerization. At that time, the residual amount of unreacted cyclic siloxane is regularly tracked to calculate the conversion rate. When the conversion rate reaches a predetermined value, the polymerization reaction is terminated by adding the chlorosilane represented by the formula (2), which is a polymerization terminator.
Thereafter, if necessary, the reaction solution is neutralized, washed with water, and distilled off by heating with a low boiling point.

The amount of cyclic siloxane is determined by an arbitrarily set conversion rate and cannot be uniquely specified. In the production method of the present invention, the molecular weight and viscosity of the obtained polyorganosiloxane can be controlled by controlling the amount of water and the conversion rate.

The conversion of cyclic siloxane can be determined by measuring the amount of cyclic siloxane in the reaction solution by gas chromatography. In order to stop the polymerization reaction at the conversion rate set before the reaction, it is preferable to track the amount of cyclic siloxane in the reaction solution and predict the stop time from the rate of decrease.

The conversion of the cyclic siloxane is not particularly limited, but in the production method of the present invention, it is 75 to 1
It is preferably in the range of 00 mol%, and more preferably in the range of 85 to 99.5 mol%. When the conversion rate is within this range, the polyorganosiloxane having a low amount of low molecular weight cyclic siloxane and a sharp molecular weight distribution can be efficiently obtained.

The temperature of the reaction solution during the polymerization reaction is not particularly limited, but it is 0 to 50 in the production method of the present invention.
It is preferably in the range of 0 ° C, and particularly preferably in the range of 10 to 30 ° C. The reaction temperature during the polymerization reaction is preferably controlled within a range of ± 2 ° C. The polymerization reaction time is until the preset conversion rate is reached.
Since the amount of the polar solvent, the type and amount of the catalyst, and the polymerization temperature (hereinafter, referred to only as the amount of the solvent in this paragraph) vary, the polymerization reaction time cannot be uniquely specified as what hours. However, in the production method of the present invention, the amount of solvent and the like are preferably adjusted so that the polymerization reaction time is in the range of 0.5 to 10 hours. It is particularly preferable to adjust the amount of solvent and the like so that the polymerization reaction time is in the range of 1 to 5 hours.

The termination of the polymerization reaction is carried out by adding the chlorosilane represented by the formula (2). The amount of the chlorosilane necessary for stopping the polymerization reaction is preferably in the range of 2 to 5 times, and particularly preferably in the range of 2 to 3 times, in terms of the molar ratio to water contained in the polymerization system.

A basic compound may be added for the purpose of capturing the generated hydrochloric acid when the polymerization reaction is stopped, as long as the effect of the production method of the present invention is not impaired. The basic compound is preferably an organic base such as triethylamine or tributylamine, and the amount thereof used is preferably in the range of 0.5 to 5 times, and in the range of 1 to 2 times the molar ratio with respect to the amount of the chlorosilane. It is particularly preferable that

An aqueous solution of a weak acid and a weak base can be used for neutralizing the reaction solution. Further, a water-soluble substance such as salt can be extracted into the aqueous layer by washing with water to remove the salt generated by neutralization, that is, by adding water to the reaction solution and stirring. Furthermore, after washing the reaction solution with water, the organic layer is separated,
After adding a dehydrating agent such as anhydrous magnesium sulfate to the organic layer, a dehydrating treatment of filtering this may be performed.

Finally, in order to remove the solvent contained in the organic layer and the cyclic trisiloxane not used in the polymerization, these low boiling components may be distilled off by heating. This heating-distillation operation is preferably performed under reduced pressure, and an evaporator or a simple distillation apparatus can be used in the laboratory.

The production method of the present invention comprises a cyclic siloxane trimer (D _{3 to} D) having a low vapor pressure in the polymerization reaction.
_{Since the amount of 10} ) produced is small, it is possible to easily control the content of the low-molecular cyclic siloxane to 500 ppm or less by distillation with a solvent cut level. On the other hand, in the equilibration reaction method and the co-hydrolysis method, a large amount of D _{3 to} D ₁₀ components are produced in the polymerization reaction, and therefore, the distillation of a solvent level can remove the low-molecular cyclic siloxane to a target level. Difficult and requires distillation at high temperature and high vacuum. In addition,
According to the production method of the present invention, even when the conversion of the cyclic siloxane is 95% or more, the polydispersity (Mw / Mn) showing a molecular weight distribution is 1.3 without accompanying side reactions such as redistribution reaction. It is possible to obtain a polyorganosiloxane having the following sharp molecular weight distribution. Since it is possible to consume most of the cyclic siloxane as a reaction raw material, it is possible to contribute to reduction of waste, improvement of productivity, and ease of production control.

The component (A) which is the base polymer of the liquid silicone rubber of the present invention is at least one selected from the polyorganosiloxanes obtained by the production method of the present invention.
More than one. Among them, the viscosity at 25 ° C is 100.
Those in the range of up to 500,000 mPa · s can be suitably used in the liquid silicone rubber of the present invention.

As the component (B), an organohydrogenpolysiloxane having at least two, preferably three or more, SiH groups in one molecule is used. The component (B) acts as a crosslinking agent,
It is used to intermolecularly crosslink the unsaturated group of the component (A) and the hydrogen group (SiH group) bonded to the silicon atom of the component (B) by a hydrosilylation reaction.

As the organohydrogenpolysiloxane, the organopolysiloxane obtained by the production method of the present invention may be used, and since the proportion of the cross-linking agent used is smaller than that of the base polymer, the above-mentioned equilibration reaction is performed. Products or co-hydrolyzed products may be used. In the liquid silicone rubber of the present invention, the component (B) is preferably an organohydrogenpolysiloxane having a viscosity in the range of 1 to 1000 mPa · s at 25 ° C.

The blending ratio of the component (B) is not particularly limited, but per 1 mol of the unsaturated group of the component (A),
The component (B) is preferably blended so that the hydrogen atom bonded to the silicon atom is in the range of 0.5 to 5 in terms of molar ratio, and more preferably in the range of 0.8 to 2.5. Preferably.

The platinum-based catalyst (C) comprises the component (A) and the component (B).
It is a catalyst for promoting the hydrosilylation reaction of the components. In the liquid silicone rubber of the present invention, the platinum catalyst is not particularly limited. Specific examples include platinum-divinyltetramethyldisiloxane complex, platinum-cyclovinylmethylsiloxane complex, chloroplatinic acid, and alcohol-modified chloroplatinic acid. The mixing ratio of the component (C) is not particularly limited, but is preferably in the range of 0.1 to 1000 ppm in terms of platinum weight based on the total amount of the components (A) and (B). .

In the liquid silicone rubber of the present invention,
In addition to the components (A), (B), and (C) described above, additives can be added as necessary. Fillers are mentioned as one of the additives. Specific examples include fumed silica, titanium dioxide, carbon black and calcium carbonate. The fillers may be surface-treated with a surface-treating agent such as an organic silane compound or an organic titanium compound. Other additives include curing inhibitors. Specific examples include tetravinyltetramethylcyclotetrasiloxane and acetylene alcohol.

The liquid silicone rubber of the present invention comprises (A)-
It is produced by mixing or kneading the component (C) and, if necessary, the above additives. The liquid silicone rubber of the present invention contains the component (A), the component (C) and, if necessary, the additive, and the component (A) and the component (B) and the additive, if necessary. It is also possible to use a two-pack type in which and are mixed at the time of use,
The components (B) and (C) and, if necessary, additives may be mixed or kneaded together to form a one-pack type.

The liquid silicone rubber of the present invention can be cured at any temperature from room temperature to 200 ° C. by adjusting the compounding conditions. The cured product can be used as an adhesive, potting agent, coating agent, etc. for electric / electronic parts.

[0046]

EXAMPLES The present invention will now be described specifically and in detail with reference to examples, but the present invention is not limited to the examples. The obtained polyorganosiloxane was measured by the following analytical method. The content of low-molecular cyclic siloxane (method of measuring the low molecular cyclic siloxane (D ₃ to D ₁₀ component)) (D ₃ to D ₁₀ component) was determined by the internal standard method using gas chromatography. The detector was FID and the column used was a capillary column. N-decane was used as the internal standard substance, and n-hexane was used as the diluting solvent. Authentic samples of cyclic siloxanes used octamethyl succitotetrasiloxane (D ₄ ) with D ₃ and D ₅
Each component of ~ D ₁₀ was converted into D ₄ and quantitatively analyzed.

(Molecular weight and dispersity measuring method) The molecular weight and dispersity measuring method was measured by gel permeation chromatography. Toluene was used as an eluent and a differential refractometer was used as a detector. The calibration curve was created using polystyrene.

(Iodine Value Measuring Method) 100 g of the sample was reacted with halogen, and the amount of halogen to be bonded was converted into the number of g of iodine to be numerically expressed (Ig / 100 g). The sample was dissolved in chloroform and reacted with a 0.1 mol / liter ICl acetic acid solution (Wis solution), and the unreacted ICl was converted to I ₂ with a KI aqueous solution. I ₂ was reacted with an aqueous starch solution to give a blue-violet solution, which was titrated with an aqueous solution of 0.1 mol / liter sodium thiosulfate to give a colorless and transparent point. The iodine value was calculated from the difference between the blank test and the titration amount when the sample was used. Furthermore, from the elementary price,
The vinyl group equivalent in the polyorganosiloxane was calculated.

¹ H-NMR and viscosity measurement were performed by known and commonly used methods. The solvent for ¹ H-NMR was CDCl ₃ , and the viscosity was an E-type rotational viscometer.

Experimental Example 1 (Method for producing polyorganosiloxane where X is a vinyl group) A 500 ml four-necked flask was equipped with a magnetic stirrer, a thermometer, a nitrogen inlet tube, and a sampling device, and hexamethylcyclotriethyl was added. 139 g of siloxane (TSL8433 manufactured by GE Toshiba Silicones Co., Ltd.), 159 g of toluene, and 15.9 g of dimethylformamide were charged. The water content in the mixed solution in the flask is 0.11
It was adjusted to g (6.1 mmol).

At a liquid temperature of 23 ° C., 200 μl of a 1.6 mol / l hexane solution of n-butyllithium (0.
(32 mmol) to initiate living anionic polymerization. The conversion of hexamethylcyclotrisiloxane was monitored by gas chromatography while controlling the reaction temperature at 25 ° C ± 2 ° C. 1.4 minutes (14 mmol) of triethylamine was added 10 minutes before the scheduled conversion time of 90%, and 2 hours after the initiation of the polymerization, 1.6 g (13 mmol) of vinyldimethylchlorosilane was added to terminate the polymerization. It was The conversion rate of hexamethylcyclotrisiloxane was 90%.

Next, the reaction solution was put into a 1-liter separatory funnel, ion-exchanged water of the same volume as the reaction solution was added, 0.5 ml of acetic acid was added and stirred, and after standing, the lower layer was extracted. It was Next, ion exchange water having the same volume as that of the upper layer was added, 1 ml of saturated aqueous sodium hydrogen carbonate was added, and the mixture was stirred. After standing, the lower layer was extracted. Furthermore, the same volume of ion-exchanged water as the upper layer was added, and stirring, standing, and extraction were repeated 3 times. After adding 15 g of magnesium sulfate to the upper layer and stirring, magnesium sulfate was removed by vacuum filtration.

A 500 ml eggplant-shaped flask was charged with the above filtrate, and the evaporator was installed and the temperature of the oil bath was 120 ° C. and the pressure was 0.5 kPa for 2 hours. The solvent and unreacted hexamethylcyclotrisiloxane were used. And low molecular weight impurities were distilled off to obtain 113 g of a colorless transparent liquid.

The ¹ H-NMR, molecular weight, dispersity, average degree of polymerization, iodine value and viscosity of the obtained colorless transparent liquid are as described below. From these analyzes, this liquid was confirmed to have the structure of the following formula. It was

¹ H-NMR δ (ppm) 0.07 (Si—CH ₃ , s, 1930H) 5.70 to 5.95 (CH ₂ , m, 4H) 6.08 to 6.17 (CH, m , 2H) Number average molecular weight (Mn): 23700 Weight average molecular weight (Mw): 26100 Dispersion degree (Mw / Mn): 1.10 Average degree of polymerization (n): 318 Iodine value: 2.25 g / 100 g Therefore vinyl group Equivalent weight: 11300 Viscosity (25 ° C.): 600 mPa · s The low molecular weight cyclic siloxane content was 200 ppm.

Experimental Example 2 (Method for producing polyorganosiloxane where X is a vinyl group) A 500 ml four-necked flask was equipped with a magnetic stirrer, a thermometer, a nitrogen inlet tube, and a sampling device, and hexamethylcyclotriethyl was added. 139 g of siloxane (TSL8433 manufactured by GE Toshiba Silicones Co., Ltd.), 159 g of toluene, and 15.9 g of dimethylformamide were charged. The amount of water in the mixed solution in the flask is 0.07
It was adjusted to 6 g (4.2 mmol).

1. Liquid n-butyllithium at a liquid temperature of 20.degree.
130 μl of 6 mol / l hexane solution (0.21
Was added to initiate living anionic polymerization. The conversion of hexamethylcyclotrisiloxane was monitored by gas chromatography while controlling the reaction temperature at 22 ° C ± 2 ° C. 0.97 g (9.6 mmol) of triethylamine was added 10 minutes before the expected conversion time of 90%, and 1.1 g (9.1 mmol) of vinyldimethylchlorosilane was added 3 hours after the initiation of the polymerization. The polymerization was stopped. The conversion rate of hexamethylcyclotrisiloxane was 90%.

Next, the reaction solution was placed in a 1-liter separatory funnel, ion-exchanged water of the same volume as the reaction solution was added, 0.3 ml of acetic acid was added, and the mixture was stirred and allowed to stand. I pulled it out. Next, ion-exchanged water having the same volume as that of the upper layer was added, 0.7 ml of saturated aqueous sodium hydrogen carbonate was added, and the mixture was stirred and left standing, and then the lower layer was extracted. Ion-exchanged water of the same volume as that of the upper layer was added, and the procedure of stirring, leaving to stand, and withdrawing the lower layer was further repeated 3 times. After adding 15 g of magnesium sulfate to the upper layer and stirring, magnesium sulfate was removed by vacuum filtration.

A 500 ml eggplant-shaped flask was charged with the above filtrate, which was attached to an evaporator and the temperature of the oil bath was 120 ° C. and the pressure was 0.3 kPa for 2 hours under the conditions of solvent, unreacted hexamethylcyclotrisiloxane. Then, low molecular weight impurities were distilled off to obtain 120 g of a colorless transparent liquid.

The ¹ H-NMR, molecular weight, dispersity, average degree of polymerization, iodine value and viscosity of the obtained colorless transparent liquid are as described below. From these analyzes, this liquid was confirmed to have the structure of the following formula. It was

¹ H-NMR δ (ppm) 0.07 (Si-CH ₃ , s, 2730H) 5.70 to 5.95 (CH ₂ , m, 4H) 6.08 to 6.17 (CH, m , 2H) Number average molecular weight (Mn): 32300 Weight average molecular weight (Mw): 36400 Dispersion degree (Mw / Mn): 1.13 Average degree of polymerization (n): 434 Iodine value: 1.57 g / 100 g Therefore vinyl group Equivalent weight: 16200 Viscosity (25 ° C.): 1550 mPa · s The low molecular weight cyclic siloxane content was 220 ppm.

Experimental Example 3 (Method for producing polyorganosiloxane where X is a vinyl group) A 500 ml four-necked flask was equipped with a magnetic stirrer, a thermometer, a nitrogen inlet tube, and a sampling device, and hexamethylcyclotriethyl was added. 139 g of siloxane (TSL8433 manufactured by GE Toshiba Silicones Co., Ltd.), 159 g of toluene, and 15.9 g of dimethylformamide were charged. The amount of water in the mixed solution in the flask is 0.05
It was adjusted to 8 g (3.2 mmol).

1. Liquid n-butyllithium at a liquid temperature of 20.degree.
100 μl of 6 mol / l hexane solution (0.16
Was added to initiate living anionic polymerization. The conversion of hexamethylcyclotrisiloxane was monitored by gas chromatography while controlling the reaction temperature at 22 ° C ± 2 ° C. 0.72 g (7.1 mmol) of triethylamine was added 10 minutes before the expected conversion time of 90%, and 0.82 g (6.7 mmol) of vinyldimethylchlorosilane was added 2 hours and 50 minutes after the initiation of the polymerization. Then, the polymerization was stopped. The conversion rate of hexamethylcyclotrisiloxane was 91%.

Next, the reaction solution was placed in a 1-liter separatory funnel, ion-exchanged water of the same volume as the reaction solution was added, 0.3 ml of acetic acid was added, and the mixture was stirred and allowed to stand. I pulled it out. Next, ion-exchanged water having the same volume as that of the upper layer was added, 0.7 ml of saturated aqueous sodium hydrogen carbonate was added, and the mixture was stirred and left standing, and then the lower layer was extracted. Ion-exchanged water of the same volume as that of the upper layer was added, and the procedure of stirring, leaving to stand, and withdrawing the lower layer was further repeated 3 times. After adding 15 g of magnesium sulfate to the upper layer and stirring, magnesium sulfate was removed by vacuum filtration.

A 500 ml eggplant-shaped flask was charged with the above filtrate, which was attached to an evaporator and the temperature of the oil bath was 120 ° C. and the pressure was 0.1 kPa for 2 hours under the conditions of solvent, unreacted hexamethylcyclotrisiloxane. And low molecular weight impurities were distilled off to obtain 122 g of a colorless transparent liquid.

The ¹ H-NMR, molecular weight, dispersity, average degree of polymerization, iodine value and viscosity of the obtained colorless transparent liquid are as described below. From these analyzes, this liquid was confirmed to have the structure of the following formula. It was

¹ H-NMR δ (ppm) 0.07 (Si-CH ₃ , s, 4000H) 5.70 to 5.95 (CH ₂ , m, 4H) 6.08 to 6.17 (CH, m , 2H) Number average molecular weight (Mn): 45700 Weight average molecular weight (Mw): 50800 Dispersion degree (Mw / Mn): 1.11 Average degree of polymerization (n): 615 Iodine value: 1.13 g / 100 g Therefore vinyl group Equivalent weight: 22500 Viscosity (25 ° C.): 3650 mPa · s Low-molecular cyclic siloxane content was 220 ppm.

Experimental Example 4 (Method for producing polyorganosiloxane where X is a vinyl group) A 300 ml four-necked flask was equipped with a magnetic stirrer, a thermometer, a nitrogen inlet tube, and a sampling device, and hexamethylcyclotrisiloxane was attached. (GE Toshiba Silicone Co., Ltd. TSL8433) 110.0 g, toluene 110.0 g, and dimethylformamide 11.0 g.
Was charged. The amount of water in the mixed solution in the flask is 0.0
It was adjusted to 40 g (2.2 mmol).

1. At a liquid temperature of 26 ° C., 1.
65 μl (0.11 mmol) of 6 mol / l hexane solution was added to initiate living anionic polymerization.
The conversion of hexamethylcyclotrisiloxane was monitored by gas chromatography while controlling the reaction temperature at 28 ° C ± 2 ° C. 0.47 g (4.6 mmol) of triethylamine was added 10 minutes before the expected conversion time of 90%, and 0.53 g (4.4 mmol) of vinyldimethylchlorosilane was added 2 hours and 05 minutes after the initiation of the polymerization. Then, the polymerization was stopped. The conversion rate of hexamethylcyclotrisiloxane was 90%.

Next, the reaction solution was put into a 1-liter separatory funnel, ion-exchanged water of the same volume as the reaction solution was added, 0.3 ml of acetic acid was added, and the mixture was stirred and allowed to stand,
The lower layer was extracted. Next, ion-exchanged water having the same volume as that of the upper layer was added, 0.7 ml of saturated sodium bicarbonate water was added, and the mixture was stirred and allowed to stand, and the lower layer was extracted. Ion-exchanged water of the same volume as that of the upper layer was added, followed by stirring, allowing to stand, and withdrawing the lower layer, which was repeated three more times. 10g magnesium sulfate on top
After adding and stirring, magnesium sulfate was removed by vacuum filtration.

A 500 ml eggplant-shaped flask was charged with the above filtrate, which was attached to an evaporator and the temperature of the oil bath was 120 ° C. and the pressure was 0.3 kPa for 2 hours. The solvent and unreacted hexamethylcyclotrisiloxane were used. And low molecular weight impurities were distilled off to obtain 85 g of a colorless transparent liquid.

The ¹ H-NMR, molecular weight, dispersity, average degree of polymerization, iodine value and viscosity of the obtained colorless transparent liquid are as described below. From these analyzes, this liquid was confirmed to have the structure of the following formula. It was

¹ H-NMR δ (ppm) 0.07 (Si—CH ₃ , s, 4620H) 5.70 to 5.95 (CH ₂ , m, 4H) 6.08 to 6.17 (CH, m , 2H) Number average molecular weight (Mn): 54400 Weight average molecular weight (Mw): 60700 Dispersion degree (Mw / Mn): 1.12 Average degree of polymerization (n): 733 Iodine value: 0.99 g / 100 g Therefore vinyl group Equivalent weight: 25600 Viscosity (25 ° C): 6900 mPa · s The low molecular weight cyclic siloxane content was 470 ppm.

Experimental Example 5 (Method for producing polyorganosiloxane where X is a vinyl group) A 2-liter four-necked flask was equipped with a stirrer, a thermometer, a nitrogen introducing tube, a capillary, and a sampling device, and hexamethylcyclohexyl was added. 500 g of trisiloxane (TSL8433 manufactured by GE Toshiba Silicones Co., Ltd.), 500 g of toluene, and 50 g of N, N′-dimethylformamide were charged. The water content in the mixed solution in the flask was adjusted to 1.8 g. N at a liquid temperature of 25 ° C
0.52 ml of a 1.55 mol / l hexane solution of -butyllithium was added to initiate living anionic polymerization. The conversion of hexamethylcyclotrisiloxane was monitored by gas chromatography while controlling the reaction temperature at 25 ° C ± 2 ° C. Polymerization initiation conversion rate is 99%
The polymerization was terminated by adding 30 g of triethylamine 10 minutes before the scheduled time to become, and adding 6 g of vinyldimethylchlorosilane 6 hours after the initiation of the polymerization. The conversion rate of hexamethylcyclotrisiloxane was 99.5%.
Next, the same water washing operation as in Experimental Example 1 was performed, and the temperature of the oil bath was 120 ° C. and the pressure was 0.5 kP using an evaporator.
The solvent, unreacted hexamethylcyclotrisiloxane and low molecular weight impurities are distilled off for 2 hours under the condition of a.
0 g of a colorless transparent liquid was obtained. Of the obtained colorless transparent liquid
¹ H-NMR, molecular weight, dispersity, average degree of polymerization and viscosity are as described below, and these analyzes confirmed that this liquid had the structure of the following formula. ¹ H-NMR δ (ppm) 0.07 (Si-CH ₃ , s, 620H) 5.70-5.95 (CH ₂ , m, 4H) 6.08-6.17 (CH, m, 2H). Number average molecular weight (Mn): 7330 Weight average molecular weight (Mw): 8170 Dispersion degree (Mw / Mn): 1.11 Average degree of polymerization (n): 97 Viscosity (25 ° C): 80 mPa · s Low molecular weight cyclic siloxane content Was 230 ppm.

Experimental Example 6 (Method for producing polyorganosiloxane in which X is a methacryloxypropyl group) A 5-liter four-necked flask was equipped with a stirrer, a thermometer, a nitrogen introducing tube, a capillary, and a sampling device, and a hexa 2000 g of methylcyclotrisiloxane (TSL8433 manufactured by GE Toshiba Silicones Co., Ltd.),
2000 g of toluene and 100 g of N, N'-dimethylformamide were charged. The amount of water in the mixed solution in the flask was adjusted to 1.43 g. Liquid temperature 27 ° C
Then, 5.9 ml of a 1.6 mol / l hexane solution of n-butyllithium was added to start living anionic polymerization. While controlling the reaction temperature at 23 ° C ± 2 ° C,
The conversion of hexamethylcyclotrisiloxane was followed by gas chromatography. 19.2 g of triethylamine was added 10 minutes before the scheduled conversion time of 90%, and 26.7 hours after the initiation of the polymerization, 36.7 g of 3-methacryloxypropyldimethylchlorosilane was added to terminate the polymerization. The conversion rate of hexamethylcyclotrisiloxane was 90%. Next, the same water washing operation as in Experimental Example 1 was performed, and the temperature of the oil bath was adjusted to 120 by using an evaporator.
The solvent, unreacted hexamethylcyclotrisiloxane and low-molecular-weight impurities were distilled off under conditions of temperature of 0.5 ° C. and pressure of 0.5 kPa for 2 hours to obtain 1830 g of a colorless transparent liquid.
The ¹ H-NMR, molecular weight, dispersity, average degree of polymerization and viscosity of the obtained colorless transparent liquid are as described below, and these analyzes confirmed that this liquid had the structure of the following formula. ¹ H-NMR δ (ppm) 0.01 (Si-CH ₃ , s, 1820H) 0.46 to 0.54 (CH ₂ , m, 4H) 1.58 to 1.68 (CH ₂ , m, 4H) ) 1.88 (CH ₃ , m, 6H) 4.04 (CH ₂ , t, 4H) 5.47 (CH ₂ =, s, 2H) 6.04 (CH ₂ =, s, 2H) number average molecular weight (Mn): 29300 Weight average molecular weight (Mw): 31400 Dispersion degree (Mw / Mn): 1.07 Average degree of polymerization (n): 390 Viscosity (25 ° C.): 970 mPa · s Low molecular cyclic siloxane content is 320 ppm. there were.

Experimental Example 7 (Method for producing polyorganosiloxane in which X is a methacryloxypropyl group) A 2-liter four-necked flask was equipped with a stirrer, a thermometer, a nitrogen inlet tube, a capillary, and a sampling device, and a hexa 800 g of methylcyclotrisiloxane (TSL8433 manufactured by GE Toshiba Silicone Co., Ltd.), 800 g of toluene, and 64 g of N, N′-dimethylformamide were charged. The water content in the mixed solution in the flask was adjusted to 1.52 g. At a liquid temperature of 25 ° C,
2.1 ml of a 1.6 mol / l hexane solution of n-butyllithium was added to initiate living anionic polymerization. The conversion of hexamethylcyclotrisiloxane was monitored by gas chromatography while controlling the reaction temperature at 25 ° C ± 2 ° C. 18.9 g of triethylamine was added 10 minutes before the expected conversion time of 90%, and 2 hours after the initiation of polymerization, 39.3 g of 3-methacryloxypropyldimethylchlorosilane was added to terminate the polymerization. The conversion rate of hexamethylcyclotrisiloxane is 9
It was 0%. Next, the same water washing operation as in Experimental Example 1 was performed, and the temperature of the oil bath was 120 ° C. using an evaporator.
The solvent, unreacted hexamethylcyclotrisiloxane and low molecular weight impurities were distilled off under a pressure of 0.5 kPa for 2 hours to obtain 720 g of a colorless transparent liquid. The ¹ H-NMR, molecular weight, dispersity, average degree of polymerization and viscosity of the obtained colorless transparent liquid are as described below, and these analyzes confirmed that this liquid had the structure of the following formula. ¹ H-NMR δ (ppm) 0.01 (Si-CH ₃ , s, 680H) 0.46-0.54 (CH ₂ , m, 4H) 1.58-1.68 (CH ₂ , m, 4H) ) 1.88 (CH ₃ , m, 6H) 4.04 (CH ₂ , t, 4H) 5.47 (CH ₂ =, s, 2H) 6.04 (CH ₂ =, s, 2H) number average molecular weight (Mn): 10900 Weight average molecular weight (Mw): 11600 Dispersion degree (Mw / Mn): 1.06 Average degree of polymerization (n): 142 Viscosity (25 ° C.): 140 mPa · s Low molecular cyclic siloxane content is 300 ppm there were.

Experimental Example 8 (Polyorganosiloxane in which X is a methacryloxypropyl group) A 2-liter four-necked flask was equipped with a stirrer, a thermometer, a nitrogen introducing tube, a capillary, and a sampling device, and hexamethylcyclotriene was attached. 700 g of siloxane (TSL8433 manufactured by GE Toshiba Silicones Co., Ltd.), 700 g of toluene, and 70 g of N, N′-dimethylformamide were charged. The amount of water in the mixed solution in the flask was adjusted to 2.91 g. At a liquid temperature of 25 ° C,
1.35 ml of a 1.56 mol / l hexane solution of n-butyllithium was added to initiate living anionic polymerization. The conversion of hexamethylcyclotrisiloxane was monitored by gas chromatography while controlling the reaction temperature at 25 ° C ± 2 ° C. 10 minutes before the scheduled conversion time of 90%, 35.9 g of triethylamine was added, and 2 hours after the initiation of polymerization, 74.9 g of 3-methacryloxypropyldimethylchlorosilane was added to terminate the polymerization. The conversion rate of hexamethylcyclotrisiloxane was 88%. Next, the same water washing operation as in Experimental Example 1 was performed, and the temperature of the oil bath was adjusted to 120 by using an evaporator.
The solvent, unreacted hexamethylcyclotrisiloxane and low molecular weight impurities were distilled off under conditions of temperature of 0.5 ° C. and pressure of 0.5 kPa for 2 hours to obtain 670 g of a colorless transparent liquid. ¹ H-NMR, molecular weight, dispersity of the obtained colorless transparent liquid,
The average degree of polymerization and the viscosity are as described below, and these analyzes confirmed that this liquid had the structure of the following formula. ¹ H-NMR δ (ppm) 0.01 (Si-CH ₃ , s, 330H) 0.46-0.54 (CH ₂ , m, 4H) 1.58-1.68 (CH ₂ , m, 4H) ) 1.88 (CH ₃ , m, 6H) 4.04 (CH ₂ , t, 4H) 5.47 (CH ₂ =, s, 2H) 6.04 (CH ₂ =, s, 2H) number average molecular weight (Mn): 5670 Weight average molecular weight (Mw): 6180 Dispersion degree (Mw / Mn): 1.09 Average degree of polymerization (n): 72 Viscosity (25 ° C.): 57 mPa · s Low molecular cyclic siloxane content is 250 ppm there were.

Experimental Example 9 (Method for producing polyorganosiloxane in which X is a methacryloxypropyl group) A 2-liter four-necked flask was equipped with a stirrer, a thermometer, a nitrogen introducing tube, a capillary, and a sampling device, and a hexa 550 g of methylcyclotrisiloxane (TSL8433 manufactured by GE Toshiba Silicones Co., Ltd.), 550 g of toluene, and 110 g of N, N'-dimethylformamide were charged. The water content in the mixed solution in the flask was adjusted to 11.6 g. At a liquid temperature of 25 ° C., 0.28 ml of a 1.56 mol / l hexane solution of n-butyllithium was added to start living anionic polymerization. The conversion of hexamethylcyclotrisiloxane was monitored by gas chromatography while controlling the reaction temperature at 23 ° C ± 2 ° C. 90% conversion
Triethylamine 136g 10 minutes before the scheduled time
2 hours after the initiation of polymerization, 292 g of 3-methacryloxypropyldimethylchlorosilane was added to terminate the polymerization. The conversion rate of hexamethylcyclotrisiloxane was 92%. Next, the same water washing operation as in Experimental Example 1 was performed, and the temperature of the oil bath was adjusted to 120 by using an evaporator.
The solvent, unreacted hexamethylcyclotrisiloxane and low-molecular-weight impurities were distilled off under conditions of temperature of 0.5 ° C. and pressure of 0.5 kPa for 2 hours to obtain 720 g of a colorless transparent liquid. ¹ H-NMR, molecular weight, dispersity of the obtained colorless transparent liquid,
The average degree of polymerization and the viscosity are as described below, and these analyzes confirmed that this liquid had the structure of the following formula. ¹ H-NMR δ (ppm) 0.01 (Si-CH ₃ , s, 75H) 0.46 to 0.54 (CH ₂ , m, 4H) 1.58 to 1.68 (CH ₂ , m, 4H) ) 1.88 (CH ₃ , m, 6H) 4.04 (CH ₂ , t, 4H) 5.47 (CH ₂ =, s, 2H) 6.04 (CH ₂ =, s, 2H) number average molecular weight (Mn): 1890 Weight average molecular weight (Mw): 2150 Dispersion degree (Mw / Mn): 1.14 Average degree of polymerization (n): 21 Viscosity (25 ° C): 15 mPa · s Low molecular cyclic siloxane content is 200 ppm there were.

Experimental Example 10 (Comparative Example: Production by Equilibration Reaction) A 500 ml four-necked flask was equipped with a stirrer, a condenser, a nitrogen inlet tube, a thermometer, and a sampling device, and octamethylcyclotetrasiloxane (GE). Toshiba Silicone Co., Ltd. TSF404) 20
0 g, divinyltetramethyldisiloxane 1.01 g,
Then, 0.1 g of KOH ground in a mortar was charged.
The equilibration reaction was carried out for 30 hours while maintaining the reaction temperature at 120 ° C ± 1 ° C. The reaction solution was cooled to 10 g of activated clay (Galleon Earth NS manufactured by Mizusawa Industry Co., Ltd.) and toluene 8
0 g was added and the mixture was stirred at room temperature for 2 hours. The activated clay was removed by vacuum filtration, and the filter residue was washed with toluene.

A 500 ml eggplant-shaped flask was charged with the above filtrate, and the evaporator was installed and the temperature of the oil bath was 120 ° C. and the pressure was 0.1 kPa for 2 hours. The solvent and unreacted hexamethylcyclotrisiloxane were used. Then, low molecular weight impurities were distilled off to obtain 160 g of a colorless transparent liquid. About 50g of this, 200 ℃,
Low boiling cut was continued for 2 hours under the condition of 0.1 kPa to obtain 49 g of a colorless transparent liquid.

The molecular weight, dispersity, average degree of polymerization, iodine value and viscosity of the colorless transparent liquid after cutting at 120 ° C. are as described below. Number average molecular weight (Mn): 39200 Weight average molecular weight (Mw): 61400 Dispersion degree (Mw / Mn): 1.57 Average degree of polymerization (n): 527 Iodine value: 1.53 g / 100 g Therefore vinyl group equivalent: 16600 Viscosity (25 ° C): 5100 mPa · s Low molecular cyclic siloxane content is 120 ° C cut product is 2
7300ppm, 12400 for 200 ℃ cut product
It was ppm.

With respect to Examples 1 to 10, Table 1 shows the items of number average molecular weight (Mn), dispersity (Mw / Mn), average degree of polymerization (n) and low molecular cyclic siloxane content (ppm).

[Table 1]

Experimental Example 11 (Production of Liquid Silicone Rubber) Vinyl group-containing polyorganosiloxane of Experimental Example 1 (viscosity 600 mPa · s, vinyl group equivalent 11300 g / mol)
100 parts by weight of a methyl H siloxane-dimethyl siloxane copolymer having a hydrogen group in its side chain (viscosity 30 mPas
-S, H equivalent 290 g / mol) 3.8 parts by weight (H / vinyl molar ratio of 1.5 / 1) were mixed. Then platinum-
The divinyltetramethyldisiloxane complex solution was added dropwise to the total amount of the vinyl group-containing polyorganosiloxane and the methyl H siloxane-dimethylsiloxane copolymer in an amount of 1 ppm in terms of platinum weight and immediately mixed to obtain a liquid silicone rubber. It was

The above liquid silicone rubber was heated at 100 ° C. for 20 minutes.
After heating for a minute, a rubber-like cured product was obtained. When the rubber-like cured product was immersed in n-hexane for 24 hours at room temperature and the content of low-molecular cyclic siloxane in the rubber was analyzed, it was 110 ppm.

[0085]

INDUSTRIAL APPLICABILITY The production method of the present invention is characterized in that the formation of cyclic siloxane 3- to 10-mer (D _{3 to} D ₁₀ ) having a low vapor pressure in the conventional polymerization reaction of cyclic siloxane is small. It is possible to easily reduce the content ratio of the cyclic siloxane contained in the polymerization reaction liquid by distillation with a solvent cut level, without subjecting the reaction liquid after the polymerization reaction to evaporation under high temperature and high vacuum. . Furthermore, in the production method of the present invention, the molecular weight and viscosity of the polyorganosiloxane obtained can be controlled by controlling the amount of cyclic siloxane and the amount of water in the solvent. Since the polyorganosiloxane obtained by the production method of the present invention has a sharp molecular weight distribution, a polyorganosiloxane having an arbitrary molecular weight distribution can be produced by polymer blending with the polyorganosiloxane having a wide molecular weight distribution. Is possible. By using the production method of the present invention, a polyorganosiloxane modified at both ends with a narrow molecular weight distribution can be obtained more efficiently, more economically and safely. Further, by using the polyorganosiloxane obtained by the production method of the present invention, it is possible to provide a liquid silicone rubber in which low molecular cyclic siloxane is removed (includes only) to the extent that silicone trouble is not caused.

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 4J002 CP04X CP14W CP16W DE186                       DE196 EC076 EX016 FD14X                       FD156 GQ00 HA01                 4J035 BA01 BA02 CA14M CA17M                       CA17U CA29U FB01 FB02                       LA02 LB03 LB20

Claims (9)

[Claims] 1. A polymer represented by the following formula (2) after polymerizing at least one cyclic siloxane represented by the following formula (1) in a solvent containing water in the presence of a lithium-based polymerization catalyst. The method for producing a polyorganosiloxane, which comprises terminating the polymerization reaction with chlorosilane. (In the formula, R ¹ and R ² are each independently an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 10 carbon atoms, a vinyl group, a trifluoropropyl group or hydrogen, and p is 3 to 10
Is an integer. ) (In the formula, R ³ and R ⁴ are each independently an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 10 carbon atoms, and X is an alkenyl group having 2 to 20 carbon atoms, a styryl group, or methacryloxypropyl. Group or acryloxypropyl group.) 2. The method for producing a polyorganosiloxane according to claim 1, wherein the solvent is a mixed solvent of a nonpolar solvent and a polar solvent. 3. The method for producing a polyorganosiloxane according to claim 1, wherein the proportion of the lithium-based polymerization catalyst is in the range of 0.001 to 1 mol with respect to 1 mol of water. 4. The molecular weight and viscosity of the resulting polyorganosiloxane are controlled by controlling the amount of cyclic siloxane and the amount of water in the solvent. A method for producing a polyorganosiloxane. 5. The chlorosilane represented by the formula (2) according to claim 1, wherein X is an alkenyl group having 2 to 20 carbon atoms, and the both-end alkenyl group-modified poly according to any one of claims 1 to 4. Method for producing organosiloxane. 6. The polymerization reaction is terminated by using chlorosilane represented by the following formula (3).
5. The method for producing a polyorganosiloxane modified with vinyl groups at both ends according to any one of claims 4 to 4. 7. The polymerization reaction is terminated by using chlorosilane represented by the following formula (4).
5. The method for producing a polyorganosiloxane modified with methacrylpropyl groups at both ends according to any one of items 1 to 4. 8. The polymerization reaction is terminated by using chlorosilane represented by the following formula (5).
5. The method for producing a polyorganosiloxane modified with an acrylic propyl group at both ends according to any one of items 1 to 4. 9. At least one polyorganosiloxane (A) selected from the polyorganosiloxanes produced by the production method according to claim 1, and at least one SiH group in one molecule. A one-component or two-component liquid silicone rubber containing two organohydrogenpolysiloxanes (B) and a platinum catalyst (C).