JPH11322937A - Production of organopolysiloxane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an organopolysiloxane having a freely controlled degree of polymerization or molecular structure by effecting the equilibration polymerization of (A) an organosilane or organosiloxane having an amide group and an SiO bond and (B) an amide-group-free organo(poly)siloxane in the presence of (C) a basic catalyst. SOLUTION: The amide group of component A is desirably the one not directly bonded to the Si atom and is typified by the one represented by the formula [wherein R<1> is a 1-10C divalent hydrocarbon group; R<2> is H, a 1-10C monovalent hydrocarbon group, or C(=O)R<4> (wherein R<4> is H or a 1-50C monovalent hydrocarbon group); and (a) is 1-10]. Component B is exemplified by a linear organo(poly)siloxane, a cyclic organo(poly)siloxane, or a branched organo(poly)siloxane. Component C is, for example, lithium hydroxide. In the equilibration polymerization, the reaction temperature is 50-200 deg.C, and the reaction time is 10 min to 50 hr.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for producing an organopolysiloxane having an amide group.
The present invention relates to a method for producing an organopolysiloxane, which can arbitrarily adjust the degree of polymerization and the molecular structure of the organopolysiloxane having an amide group.

[0002]

2. Description of the Related Art As a method for producing an organopolysiloxane having an amide group, there is known a method in which an organopolysiloxane having an amino group is reacted with a carboxylic acid by heating (Japanese Patent Publication No. 36-7014, and Japanese Patent Application Laid-Open No. 6-220325).
JP-A-56-74113 and JP-A-57-101076, a method of reacting an organopolysiloxane having an amino group with a carboxylic anhydride or a carboxylic acid chloride. A method of subjecting an organopolysiloxane having a silicon-bonded hydrogen atom to an addition reaction with a higher fatty acid amide compound having an unsaturated group in a molecule using a platinum-based catalyst (JP-A-5-209)
No. 130) has been proposed.

However, JP-B-36-7014, JP-A-6-220325, and JP-A-56-74.
In the method proposed in JP-A-113-113 and JP-A-57-101076, it is difficult to confirm whether or not the reaction is completed, and the unreacted carboxylic acid, carboxylic anhydride, or carboxylic acid There is a problem that it is difficult to remove the substance from the organopolysiloxane. Furthermore, when a carboxylic acid chloride is used, a basic substance must be added to supplement hydrochloric acid produced as a by-product, and furthermore, an organic solvent or a large amount of water for performing a uniform reaction must be added. Therefore, there was a problem that the pot efficiency was extremely poor. Further, the method proposed in JP-A-5-209130 has a problem that the platinum-based catalyst is often poisoned by impurities contained in the higher fatty acid amide compound, and the reaction does not proceed sufficiently.

In these methods, the degree of polymerization or molecular structure of the organopolysiloxane used as a raw material becomes the same as the degree of polymerization or molecular structure of the desired organopolysiloxane having an amide group. There is a problem that it is necessary to adjust the degree of polymerization and the molecular structure of the siloxane.

[0005]

DISCLOSURE OF THE INVENTION The present inventors have intensively studied the above-mentioned problems, and as a result, have reached the present invention. That is, an object of the present invention is to provide a method for producing an organopolysiloxane in which the degree of polymerization and the molecular structure of the organopolysiloxane having an amide group can be arbitrarily adjusted.

[0006]

The process for producing an organopolysiloxane having an amide group according to the present invention comprises: (A) an organosilane or an organosiloxane having an amide group and a SiO bond; and (B) an organosilane having no amide group.
(C) equilibrium polymerization with (C) a basic catalyst.

[0007]

DETAILED DESCRIPTION OF THE INVENTION The organosilane or organosiloxane of the component (A) is a compound having an amide group and an SiO bond, and is a raw material for introducing an amide group into a target organopolysiloxane. It is preferable that the amide group in the component (A) does not directly bond to a silicon atom.

Embedded image Is a group represented by R ¹ in the above formula is the same or different and is a divalent hydrocarbon group having 1 to 10 carbon atoms, specifically, an alkylene group such as a methylene group, an ethylene group, a propylene group, a butylene group; a phenylene group And an alkylene arylene group such as a methylene phenylene group. R ² in the above formula is the same or different, and is a hydrogen atom, a monovalent hydrocarbon group having 1 to 10 carbon atoms, and a general formula:

Embedded image And a group selected from the group consisting of an acyloxy group represented by Examples of the monovalent hydrocarbon group for R ² include a methyl group,
Examples include alkyl groups such as ethyl group, propyl group and butyl group; alkenyl groups such as vinyl group, allyl group and butenyl group; and aryl groups such as phenyl group, tolyl group and xylyl group. In the acyloxy group for R ² , R ⁴ in the formula is a hydrogen atom or a monovalent hydrocarbon group having 1 to 50 carbon atoms, and the monovalent hydrocarbon group for R ⁴ includes a methyl group and an ethyl group. And alkenyl groups such as vinyl group, allyl group and butenyl group; and aryl groups such as phenyl group, tolyl group and xylyl group. Examples of such an acyloxy group for R ² include an acetoxy group, a hexanoyl group, and an acryloyl group.
R ³ in the above formula is a hydrogen atom or a group having 1 to 1 carbon atoms.
50 monovalent hydrocarbon groups, examples of R ³ monovalent hydrocarbon groups include alkyl groups such as methyl group, ethyl group, propyl group and butyl group; alkenyl groups such as vinyl group, allyl group and butenyl group; An aryl group such as a phenyl group, a tolyl group and a xylyl group is exemplified. A in the above formula is an integer in the range of 0 to 10. In the production method of the present invention, R ² in the above formula is the monovalent hydrocarbon group, and a is 0
It is preferred that

Examples of the organosilane (A) include an organoalkoxysilane having an amide group and an organohydroxysilane having an amide group.
Specifically, the following organosilanes are exemplified.

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As a method for preparing the organosilane as the component (A), a method of reacting an organosilane having an amino group and a SiO bond with a carboxylic acid, a carboxylic anhydride, or a chloride of a carboxylic acid, An example is a method in which an organosilane having a silicon-bonded hydrogen atom and a SiO bond is subjected to an addition reaction with an amide compound having an aliphatic unsaturated group in a molecule using a platinum-based catalyst.

As the organosiloxane (A), a straight-chain organosiloxane having an amide group may be used.
Examples thereof include a cyclic organosiloxane having an amide group and a branched-chain organosiloxane having an amide group. Specific examples include the following organosiloxanes.

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As a method for preparing such an organosiloxane as the component (A), a method of reacting an organosiloxane having an amino group with a carboxylic acid, a carboxylic anhydride, or a chloride of a carboxylic acid, a silicon atom bond, Examples include a method in which an organopolysiloxane having a hydrogen atom and an amide compound having an aliphatic unsaturated group in a molecule are subjected to an addition reaction with a platinum-based catalyst, and in particular, it is possible to confirm whether or not the reaction is completed. Since it is possible to easily remove unreacted carboxylic acid, carboxylic anhydride, or carboxylic acid chloride from the organosiloxane, it is preferable to use an organosiloxane having 50 or less silicon atoms as a raw material, Further, it is preferable to use an organosiloxane having 20 or less silicon atoms as a raw material. Properly, in particular, the number of silicon atoms is 10
It is preferable to use the following organosiloxane as a raw material. Further, it is preferable to use a cyclic organosiloxane as such an organopolysiloxane. The amide group-containing organopolysiloxane thus prepared has a relatively high amide group content, and by using this, the amide group content in the organopolysiloxane can be arbitrarily adjusted. There is an advantage.

The organo (poly) siloxane of the component (B) is
It is a compound having no amide group, and is a component for increasing the degree of polymerization of the target organopolysiloxane having an amide group. Examples of the organo (poly) siloxane of the component (B) include linear organosiloxanes, linear organopolysiloxanes, cyclic organosiloxanes, cyclic organopolysiloxanes, branched organosiloxanes, and branched organosiloxanes. A chain organopolysiloxane is exemplified. In particular, the component (B) is preferably a cyclic organosiloxane because the degree of polymerization of the desired organopolysiloxane having an amide group can be easily adjusted. Further, for the purpose of adjusting the molecular structure of the desired organopolysiloxane having an amide group, a branched organopolysiloxane may be used. Examples of the group bonded to the silicon atom of the component (B) include an alkyl group such as a methyl group, an ethyl group and a propyl group; an alkenyl group such as a vinyl group, an allyl group and a butenyl group; a phenyl group, a tolyl group and a xylyl group. An aryl group such as a group; a substituted or unsubstituted monovalent hydrocarbon group such as a halogenated alkyl group such as a 3,3,3-trifluoropropyl group; an alkoxy group such as a methoxy group or an ethoxy group; a hydroxyl group; Is exemplified.

As the organo (poly) siloxane of the component (B), hexamethylcyclotrisiloxane,
Octamethylcyclotetrasiloxane, 1,3,5-trimethyl-1,3,5-triphenylcyclotrisiloxane, 1,3,5,7-tetramethyl-1,3,5,7
-Tetraphenylcyclotetrasiloxane, hexaphenylcyclotrisiloxane, octaphenylcyclotetrasiloxane, 1,3,5-trimethyl-1,3,5-
Cyclic organo (poly) siloxanes such as trivinylcyclotrisiloxane and 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane; hexamethyldisiloxane, 1,1,3 , 3-Tetramethyldisiloxane, 1,3-divinyl-1,1,3,3-
Tetramethyldisiloxane, 1,3-dihydroxy-
1,1,3,3-tetramethyldisiloxane, dimethylpolysiloxane with trimethylsiloxy group at both ends of molecular chain, methylphenylpolysiloxane with trimethylsiloxy group at both ends of molecular chain, dimethylsiloxane / diphenyl with trimethylsiloxy group at both ends of molecular chain Linear organo (poly) such as siloxane copolymer, dimethylpolysiloxane with hydroxyl groups blocked at both ends of molecular chains, methylphenylpolysiloxane with hydroxyl groups at both ends of molecular chains, dimethylsiloxane / diphenylsiloxane copolymer with both molecular ends at hydroxyl groups Siloxane is exemplified.

The basic catalyst of component (C) is a catalyst for equilibrium polymerization of the organosilane or organosiloxane of component (A) with the organo (poly) siloxane of component (B). Examples of the basic catalyst of the component (C) include alkali hydroxides such as lithium hydroxide, sodium hydroxide, potassium hydroxide, cesium hydroxide, rubidium hydroxide, tetramethylammonium hydroxide, and tetrabutylphosphonium hydroxide. Hydroxide: alkali silanolate such as lithium silanolate, sodium silanolate, potassium silanolate, cesium silanolate, tetramethylammonium silanolate, tetrabutylphosphonium silanolate; butyllithium, methyllithium, sodium naphthalenide, potassium An organic metal compound such as naphthalenide is exemplified. In particular, in order to carry out sufficient equilibrium polymerization, it is preferable that the basic catalyst as the component (C) has potassium, cesium, and tetramethylammonium as alkaline components.

In the method of the present invention, a conventionally known polymerization accelerating solvent may be used for the purpose of accelerating the equilibrium polymerization. The use of this polymerization-promoting solvent is preferable because the equilibrium polymerization easily proceeds at a relatively low temperature and the decomposition reaction of the amide group during the equilibrium polymerization can be suppressed. Examples of such a polymerization accelerating solvent include polar organic solvents such as tetrahydrofuran, dimethylformamide, dimethylsulfoxide, and acetonitrile.

In the method of the present invention, the desired organopolysiloxane having an amide group can be prepared by subjecting component (A) and component (B) to equilibrium polymerization with component (C). The reaction temperature of this equilibrium polymerization is 50-200.
It is preferably performed within a temperature range of 50 ° C, but in order to sufficiently suppress the decomposition of the amide group, it is more preferable to perform the process within a temperature range of 50 to 150 ° C.
It is particularly preferred to work within the temperature range of ° C. The reaction time of the equilibrium polymerization depends on the above-mentioned reaction temperature, and the higher the reaction temperature, the shorter the reaction time, but generally, the longer the reaction time, the faster the decomposition reaction of the amide group. Therefore, the reaction time is preferably in the range of 10 minutes to 50 hours.
It is particularly preferred that it is within the range of 0 minutes to 20 hours. In the method of the present invention, a solvent other than the above-mentioned polymerization accelerating solvent may be used, and examples thereof include aromatic hydrocarbons such as benzene, xylene and toluene; and aliphatic hydrocarbons such as hexane and heptane. This equilibrium polymerization is tracked by measuring the viscosity of the reaction mixture, or measuring the concentration of the raw material by gas chromatography, and confirming that the viscosity has reached an equilibrium state when the viscosity becomes constant or when the raw material disappears. This can be achieved by deactivating the basic catalyst. Examples of the method of deactivating the basic catalyst include a method of adding an acidic substance to neutralize the basic catalyst and a method of thermally decomposing the basic catalyst itself. Then, after deactivating the basic catalyst, by-products having a low boiling point in the reaction mixture are distilled off under reduced pressure, whereby the desired organopolysiloxane having an amide group can be prepared.

[0017]

EXAMPLES The method for producing the organopolysiloxane of the present invention will be described in detail with reference to examples. The viscosity is a value at 25 ° C.

Reference Example 1 Under nitrogen atmosphere, stirrer, reflux
Dehydration tube with a tube, and 1 L of flask with thermometer
In the formula:

Embedded image 395.5 g of a cyclic organosiloxane having an Nt-butylaminopropyl group and toluene 20
0 mL was added and azeotropic dehydration was performed. After cooling to room temperature, 56 g of triethylamine was added. Further, after dropwise adding 120.5 g of lauric chloride at room temperature while cooling in a water bath,
Stir at room temperature for 3 hours. After completion of the reaction, low-boiling substances were distilled off from the reaction mixture under reduced pressure at 60 ° C. and 25 mmHg. Then, n
-200 mL of hexane was added to precipitate the salt. After the salt was filtered off, low-boiling substances were distilled off from the filtrate under reduced pressure at 70 ° C., 25 mmHg and further at 5 mmHg to obtain 211 g of a brownish brown viscous liquid.

The brown transparent viscous liquid is analyzed by infrared spectroscopy.
(Hereinafter referred to as IR) spectrum, the absorption at 1800 cm ^-1 observed in the raw material disappeared, and
An absorption of an amide group was observed at 655 cm ^-1 . Also, ¹³ C
-, And from the measurement results of ²⁹ Si-nuclear magnetic resonance analysis (hereinafter, NMR) spectrum, this brown transparent viscous liquid,
formula:

Embedded image It was confirmed that it was a cyclic organosiloxane having a lauric acid amide group represented by.

Reference Example 2 Under nitrogen atmosphere, stirrer, reflux
Dehydration tube with a tube, and a 200 mL filter equipped with a thermometer
In Lasco, use the Nt-butylaminop used in Reference Example 1.
11.5 g of cyclic organosiloxane having a propyl group
And 30 mL of toluene were added, and azeotropic dehydration was performed. Cool to room temperature
Thereafter, 6.9 g of pyridine and 8.0 g of acetic anhydride were added, and the mixture was
The mixture was stirred at room temperature under flowing conditions for 3 hours. After the reaction is complete, mix the reaction
Low-boiling substances at 70 ° C, 25mmHg, and further reduced to 5mmHg
By distilling off, 13.8 g of a brown-brown transparent high-viscosity liquid was obtained.
I got

The brownish transparent highly viscous liquid was found to have an amide group absorption at 1655 cm ^-1 by IR spectrum analysis. Further, from the measurement results of the ¹³ C- and ²⁹ Si-NMR spectra, this brown transparent highly viscous liquid has the formula:

Embedded image It was confirmed to be a cyclic organosiloxane having an acetic acid amide group represented by.

Reference Example 3 Under nitrogen atmosphere, stirrer, reflux
Dehydration tube with a tube, and a 300 mL filter equipped with a thermometer
In Lasco, use the Nt-butylaminop used in Reference Example 1.
12.3 g of cyclic organosiloxane having a propyl group
And 40 mL of toluene were added, and azeotropic dehydration was performed. Cool to room temperature
Thereafter, 7.5 g of triethylamine were added. In addition, dehydration
Cool 22.8 g of pear oil fatty acid chloride in a water bath
Then, the mixture was added dropwise at room temperature and stirred for 1 hour at room temperature. End of reaction
After that, low boiling point substances were reduced from the reaction mixture at 60 ° C and 25 mmHg.
Distilled off. Next, 50 mL of n-hexane was added to remove the salt.
Settled. After filtering off the salt, 70 ppm of low boiling point substances are removed from the filtrate.
At 25 ° C., 25 mmHg and then 5 mmHg.
24.9 g of a brownish transparent viscous liquid were obtained.

Analysis of this brownish viscous liquid by IR spectroscopy revealed that the absorption at 1800 cm ^-1 observed in the raw material disappeared and that the absorption of an amide group was observed at 1655 cm ^-1 instead. In addition, ¹³ C- and ²⁹ Si-NMR
According to the spectrum measurement result, this brown transparent viscous liquid has the formula:

Embedded image It was confirmed to be a cyclic organosiloxane having a dehydrated castor oil fatty acid amide group represented by.

[Example 1] Under nitrogen atmosphere, stirrer, reflux
Reference Example 1 was placed in a 5 L flask equipped with a tube and a thermometer.
Cyclic orga having a lauric amide group prepared in
69g of siloxane and molecular chain of 80 centipoise viscosity
Dimethylpolysiloxane having a terminal silanol group blocked, and
2.7 g of potassium hydroxide were added. 110 ° C to 120 ° C
After stirring for 3 hours at room temperature, the temperature was lowered to 60 ° C.
And 5 g of acetic acid is added, and the mixture is further stirred for 2 hours.
Lium was neutralized. To the obtained organopolysiloxane
800 mL of toluene was added and filtered. Low boiling point from filtrate
The substance is distilled off under reduced pressure at 70 ° C, 25 mmHg and further at 5 mmHg.
The viscosity is 4000 centipoise, and it is pale yellow and transparent
2,915 g of a viscous liquid were obtained.

When the pale yellow transparent viscous liquid was analyzed by IR spectrum, absorption of an amide group was observed at 1655 cm ^-1 . From the measurement results of ¹³ C- and ²⁹ Si-NMR spectra, this pale yellow transparent viscous liquid was
It was confirmed that it was an organopolysiloxane having a lauric acid amide group of 0.5 mol% as shown in the following formula.

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[Example 2] Under nitrogen atmosphere, stirrer, reflux
In a 300 mL flask equipped with a tube and a thermometer,
Cyclic organo having an amide amide group prepared in Example 2.
2.2 g of siloxane and both molecular chains having a viscosity of 80 centipoise
Dimethylpolysiloxane 149 having a terminal silanol group blocked
g, and 0.1 g of potassium hydroxide. 110 ° C
After stirring and polymerizing at ~ 120 ° C for 2 hours, the temperature was raised to 60 ° C.
And add 0.2 g of acetic acid and stir for an additional 2 hours
Thus, potassium hydroxide was neutralized. Obtained Oh
Add 100 mL of toluene to the luganopolysiloxane and filter.
I have. 70 ° C, 25mmHg, 5
By vacuum distillation at mmHg, viscosity 22000cm
124 g of a light yellow transparent viscous liquid of poise were obtained.

When this pale yellow transparent viscous liquid was analyzed by IR spectrum, absorption of an amide group was observed at 1655 cm ^-1 . From the measurement results of ¹³ C- and ²⁹ Si-NMR spectra, this pale yellow transparent viscous liquid was
It was confirmed to be an organopolysiloxane represented by the following formula and having an amide group of 0.5 mol%.

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[Embodiment 3] Under nitrogen atmosphere, stirrer, reflux
In a 300 mL flask equipped with a tube and a thermometer,
Dehydrated castor oil prepared in Example 3 having a fatty acid amide group
11.5 g of cyclic organosiloxane and octamethyl
Clotetrasiloxane 500 g, water 2 g, and hydroxylated
0.9 g of potassium was added. 2 hours at 110 ° C to 120 ° C
After stirring for polymerization, the temperature was lowered to 60 ° C.
Add 2 g and stir for an additional 2 hours to effect hydroxylation
Potassium was neutralized. The resulting organopolysiloxane
To the mixture was added 200 mL of toluene, followed by filtration. Low boiling from filtrate
Distill the residue at 70 ° C, 25 mmHg, and further under 5 mmHg under reduced pressure.
The light yellow color has a viscosity of 31,000 centipoise
461 g of a transparent viscous liquid were obtained.

When the pale yellow transparent viscous liquid was analyzed by IR spectrum, absorption of an amide group was observed at 1655 cm ^-1 . From the measurement results of ¹³ C- and ²⁹ Si-NMR spectra, this pale yellow transparent viscous liquid was
The dehydrated castor oil fatty acid amide group represented by the following formula is 0.5
It was confirmed that the organopolysiloxane had mol%.

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Example 4 Under a nitrogen atmosphere, water 10 was placed in a 2.0 L flask equipped with a stirrer, a reflux tube, and a thermometer.
0 g, toluene 400 g, and isopropanol 14
0 g, the system was cooled to 10 ° C., 336.7 g of phenyltrichlorosilane,
A solution composed of 8.1 g and 126 g of toluene was gradually added dropwise. After the completion of the dropwise addition, the mixture was heated under reflux for 1 hour,
The toluene solution was separated. The separated toluene solution was washed with 300 g of water and repeated until the washing solution became neutral. By adjusting the solid content, the silicone resin
452 g of a wt.% Toluene solution were obtained.

[0031] Under a nitrogen atmosphere, stirrer, reflux tube, and temperature
In a 300 mL flask equipped with a
Resin toluene solution 42.6g, prepared in Reference Example 3
Also, a cyclic orga having a dehydrated castor oil fatty acid amide group.
17.4 g of siloxane, 61 g of toluene and potassium hydroxide
0.07 g of Pt.
Let go. After the distilling of water, the solid content becomes more than 50%
After the toluene has been distilled off as
Cool. Measure the solids content of the reaction mixture and determine the amount of toluene.
By adjusting the concentration of the reaction mixture to 50% by weight.
Then, heating and reflux were performed again. Temporarily mix the reaction mixture
Sampling is performed at intervals, and this sample is neutralized.
After that, it is separated by gel permeation chromatography.
The child size was measured. After 6 hours, the molecular weight of the sample becomes constant
The reaction mixture was cooled and acetic acid
0.04 g was added. The generated potassium acetate is filtered
After that, the filtrate is heated under reduced pressure to distill off the solvent.
As a result, 36.8 g of a solid substance was obtained.

The number average molecular weight of this solid product is 4880,
The weight average molecular weight was 7,865. The solid was analyzed by IR spectrum to find that it was 1655 cm
^{At -1} , absorption of an amide group was observed. Also, from the measurement results of the ¹³ C- and ²⁹ Si-NMR spectra, it was confirmed that this solid was an organopolysiloxane having the following formula and having 18 mol% of a dehydrated castor oil fatty acid amide group.

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[0033]

According to the process for producing an organopolysiloxane of the present invention, the degree of polymerization and the molecular structure of the organopolysiloxane having an amide group can be arbitrarily adjusted, and the content of the amide group in the organopolysiloxane can be reduced. It has the feature that it can be adjusted as desired.

Claims (4)

[Claims] (1) An organosilane or an organosiloxane having an amide group and a SiO bond and (B) an organo (poly) siloxane having no amide group are represented by (C)
A method for producing an organopolysiloxane having an amide group, comprising carrying out equilibrium polymerization with a basic catalyst. 2. The amide group in the component (A) has a general formula: Wherein R ¹ is the same or different and has 1 to 1 carbon atoms.
0 is a divalent hydrocarbon group, R ² is the same or different, a hydrogen atom, a monovalent hydrocarbon group having 1 to 10 carbon atoms,
And the general formula: (Wherein, R ⁴ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 50 carbon atoms), and R ³ is a hydrogen atom, or A monovalent hydrocarbon group having 1 to 50 carbon atoms, and a is 0
Is an integer of 10 to 10. 2. The method for producing an organopolysiloxane according to claim 1, wherein the group is a group bonded to a silicon atom represented by｝. 3. The method for producing an organopolysiloxane according to claim 2, wherein R ² is a monovalent hydrocarbon group having 1 to 10 carbon atoms and a is 0. 4. The method for producing an organopolysiloxane according to claim 1, wherein the component (A) is a cyclic organosiloxane.