JPH07138267A - Vinyl-and alkoxy-functional organic silicon compound and its production - Google Patents

Abstract

PURPOSE:To efficiently obtain an organic silicon compound having a vinyl group and an alkoxy group having high condensation reactivity with a silanol group, and useful as a coupling agent, etc., by subjecting a specific siloxane and a specified alkoxysilane to a reequillibrim reaction in the presence of an acidic catalyst. CONSTITUTION:A compound of formula I (R is 1-4C alkyl; a is 1, 2), concretely, a compound of formula II (Vi is vinyl group; Me is methyl), etc. This compound is obtained by subjecting syn-divinyltetramethyldisiloxane and a vinyltrialkoxysilane to a reequillibrium reaction in the presence of an acidic catalyst. E.g. active China clay, etc., is preferably used as the catalyst.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel vinylalkoxy functional organosilicon compound and a method for producing the same. Specifically, it relates to a novel vinylalkoxy-functional organosilicon compound having an alkoxy group having high reactivity with a silanol group, and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, a large number of alkoxy-functional organosilicon compounds in which an alkoxy group is bonded to a silicon atom are known. These are coupling agents for bonding glass fibers and organic resins, silicone polymers and organic polymers. Widely used as a chain extender or crosslinking agent. Examples of such an alkoxy-functional organosilicon compound include a monofunctional alkoxysilane containing one alkoxy group, a bifunctional alkoxysilane containing two alkoxy groups, and a trifunctional alkoxysilane containing three alkoxy groups. Alkoxysilanes and tetrafunctional alkoxysilanes containing four alkoxy groups are known. The hydrolysis reactivity of the alkoxy group in the alkoxysilane and the condensation reactivity with the silanol group become lower as the number of the alkoxy groups decreases, so that the reactivity of the bifunctional alkoxysilane or the trifunctional alkoxysilane is lower. It had the drawback of being much lower than that of tetrafunctional alkoxysilanes. Therefore, an alkoxy-functional organosilicon compound having a high reactivity equivalent to that of the tetrafunctional alkoxysilane is desired. The present inventors previously disclosed, as a chain extender, an alkoxy-functional organosilicon compound represented by the formula: ((CH ₃ ) ₃ SiO) ₂ Si (OCH ₃ ) ₂ by Japanese Patent Application No. 4-187661. Proposed. However, the condensation reactivity of the alkoxy group of the alkoxy-functional organosilicon compound with the silanol group is not so high,
It was not completely satisfactory depending on the application. Also,
Vinyl group-containing alkoxysilanes, which are represented by vinylmethyldimethoxysilane and vinyltrimethoxysilane, and have an alkoxy functional group different from the alkoxysilyl group are also expected to be applied as chain extenders and crosslinkers.
However, these vinyl group-containing alkoxysilanes also have drawbacks such as insufficient condensation reactivity of alkoxy groups with silanol groups.

[0003]

The present inventors have arrived at the present invention as a result of extensive studies to solve the above-mentioned drawbacks.
That is, an object of the present invention is to provide a novel vinylalkoxy functional organosilicon compound having a vinyl group and an alkoxy group having a high condensation reactivity with a silanol group, and a method for producing the same.

[0004]

The present invention has the general formula:

[Chemical 2] (In the formula, R is an alkyl group having 1 to 4 carbon atoms, and a
Is 1 or 2. ), A vinylalkoxy-functional organosilicon compound, and a re-equilibration reaction of syn-divinyltetramethyldisiloxane and vinyltrialkoxysilane in the presence of an acidic catalyst, a general formula:

[Chemical 3] (In the formula, R is an alkyl group having 1 to 4 carbon atoms, and a
Is 1 or 2. ) Relates to a method for producing a vinylalkoxy-functional organosilicon compound.

The vinylalkoxy functional organosilicon compounds of the present invention have the general formula:

[Chemical 4] It is represented by. In the above formula, R is an alkyl group having 1 to 4 carbon atoms, and is a methyl group, an ethyl group, a normal propyl group,
Examples include isopropyl group, normal butyl group, isobutyl group, and tertiary butyl group. Of these, a methyl group or an ethyl group is preferable, and a methyl group is particularly preferable. a is 1 or 2. Specific examples of such a vinylalkoxy-functional organosilicon compound include compounds represented by the following formula. In the following formula, Vi represents a vinyl group, Me represents a methyl group, and Et represents an ethyl group. Formula: (ViMe ₂ SiO) ₂ SiVi (OMe) ₁ Formula: (ViMe ₂ SiO) ₁ SiVi (OMe) ₂ Formula: (ViMe ₂ SiO) ₂ SiVi (OEt) ₁ Formula: (ViMe ₂ SiO) ₁ SiVi (OEt) ) ₂

Such a vinylalkoxy-functional organosilicon compound of the present invention can be produced by re-equilibrating syn-divinyltetramethyldisiloxane and vinyltrialkoxysilane in the presence of an acidic catalyst. . The syn-divinyltetramethyldisiloxane and vinyltrialkoxysilane used in the production method of the present invention are widely used industrially. Among them, vinyltrialkoxysilane includes vinyltrimethoxysilane,
Examples are vinyltriethoxysilane and vinyltrinormal propoxysilane. In the manufacturing method of the present invention,
The amount of syn-divinyltetramethyldisiloxane and the amount of vinyltrialkoxysilane are represented by the formula: ViMe ₂ SiO (wherein Vi represents a vinyl group and Me represents a methyl group) in the vinyltrialkoxysilane. 1 organic group
When introducing one or two, it is generally a rule to add 1 mol or 2 mol of syn-divinyltetramethyldisiloxane to 1 mol of vinyltrialkoxysilane, respectively. The acidic catalyst used in the production method of the present invention may be one that does not adversely affect the reaction system,
Specific examples include acid-treated inorganic compounds such as activated clay, trifluorosulfonic acid, and dodecylbenzenesulfonic acid. The reaction product obtained by re-equilibrating syn-divinyltetramethyldisiloxane and vinyltrialkoxysilane has the formula: (ViMe ₂ S
iO) _X SiVi (OR) _3-X (where R is 1 carbon atom)
Is an alkyl group of 4 and x is a number of 0 to 3. Vi
Represents a vinyl group, and Me represents a methyl group. ) Is a mixture containing an organosilicon compound as a main component. By distilling this mixture, the desired vinylalkoxy-functional organosilicon compound can be obtained. In this re-equilibration reaction, one of the alkoxy groups in vinyl trialkoxysilane is substituted with an organic group represented by the formula: ViMe ₂ SiO (wherein Vi represents a vinyl group and Me represents a methyl group). Each time, the formula: ViMe ₂ SiOR
(In the formula, R is an alkyl group having 1 to 4 carbon atoms. V
i represents a vinyl group, and Me represents a methyl group. 1 molecule of vinyldimethylalkoxysilane represented by Therefore, it is preferable to proceed the reaction while distilling it off. The vinyl dimethylalkoxysilane produced as a by-product is
After hydrolyzing to syn-divinyltetramethyldisiloxane, this can be used as a raw material used in the production method of the present invention. The other by-produced organosilicon compound can be reused in addition to the equilibration reaction. The re-equilibration reaction starts around 70 ° C and is finally completed at 100 to 150 ° C. As the reaction progresses, the temperature at which the by-produced vinyldimethylalkoxysilane can be distilled off increases. After completion of the reaction, it is preferable to remove the acidic catalyst from the reaction product by neutralizing or filtering the reaction product. Incidentally, such a reaction may be carried out in the presence of an organic solvent.

In the vinylalkoxy-functional organosilicon compound of the present invention, a dimethylvinylsilyl group is bonded to one silicon atom via an alkoxy group, a vinyl group and an oxygen atom. It has high condensation reactivity and can react with other reactions by vinyl group. Therefore, by utilizing such characteristics, it is very useful as a coupling agent for binding glass fiber and an organic resin, a chain extender or a cross-linking agent for a silicone polymer or an organic polymer.

[0008]

EXAMPLES Next, the present invention will be described with reference to examples. In the examples, Vi and Me represent a vinyl group and a methyl group, respectively. Further, the identification of the vinylalkoxy-functional organosilicon compound was performed by ¹ H-nuclear magnetic resonance analysis and infrared spectroscopic analysis. The viscosity is a measured value at 25 ° C.

[0009]

Example 1 296.4 g (2.0 mol) of vinyltrimethoxysilane and syn-divinyltetramethyldisiloxane 372 were placed in a 1-liter four-necked flask equipped with a stirrer, a thermometer, and a device capable of simple distillation. 0.4 g (2.0 mol) and a cation exchange resin [manufactured by Mitsubishi Kasei Co., Ltd., trade name: Diaion RCP150HD] were charged. Liquid temperature is 100
The mixture was heated to ℃ and reacted with stirring. During the reaction, vinyl dimethylmethoxysilane produced as a by-product was distilled out of the reaction system. During the heated reaction, the reaction mixture was sampled from time to time and analyzed by gas chromatographic analysis.
The formula occupied in the reaction mixture 20 hours after the start of the reaction:
The content of the vinylalkoxy-functional organosilicon compound represented by (ViMe ₂ SiO) SiVi (OMe) ₂ is 35.
-40% by weight. The reaction was stopped here. After cooling, the resulting reaction mixture was filtered to remove the cation exchange resin. Then, the reaction mixture after the filtration was put into a Vigreux fractionation apparatus and fractionated to obtain a compound of the formula: (ViMe ₂ Si
O) 170 g of a crude fraction containing a large amount of vinylalkoxy-functional organosilicon compound represented by SiVi (OMe) _2.
Got This crude fraction was distilled under reduced pressure using a rotary band precision fractionation device to give a formula having a boiling point of 71 ° C./20 mmHg: (ViMe
36 g of vinylalkoxy-functional organosilicon compound represented by ₂ SiO) SiVi (OMe) ₂ were obtained. The purity of this vinylalkoxy functional organosilicon compound was 99%. The refractive index was 1.4080.

[0010]

Example 2 The reaction mixture after filtration obtained in Example 1 was placed in a Vigreux fractionator and fractionated to obtain the compound of the formula: (ViM
e ₂ SiO) ₂ SiVi (OMe) -containing crude fraction 4 having a high content of vinylalkoxy-functional organosilicon compound
5 g was obtained. This crude fraction was distilled under reduced pressure using a rotary band precision fractionator to obtain a compound having a boiling point of 102 ° C./20 mmHg: (V
28 g of vinylalkoxy-functional organosilicon compound represented by iMe ₂ SiO) ₂ SiVi (OMe) was obtained. The purity of this vinylalkoxy functional organosilicon compound is 98
%Met. Its refractive index was 1.4161.

[0011]

[Application] The reactivity of the vinylalkoxy-functional organosilicon compound of the present invention with dimethylpolysiloxane having silanol groups at both ends was evaluated. A mixture of 0.3 g of the vinylalkoxy-functional organosilicon compound obtained in Example 1 and 0.03 g of dibutyltin laurate was added to 5 g of dimethylpolysiloxane blocked with silanol groups at both ends (viscosity 12,500 centipoise) to obtain a uniform mixture. Mixed with
A room temperature curable organopolysiloxane composition was prepared.
When this composition was allowed to stand at room temperature and the viscosity change rate after 3 hours was measured, the viscosity change rate was 1280%. Here, the viscosity change rate was calculated according to the following equation. Viscosity change rate (%) = [(viscosity after 3 hours-viscosity immediately after production)]
/ Viscosity immediately after production] × 100 For comparison, instead of the vinylalkoxy-functional organosilicon compound obtained in Example 1 above, the formula:
A room temperature curable organopolysiloxane composition was prepared in the same manner as above except that an organosilicon compound represented by (Me ₃ SiO) ₂ Si (OMe) ₂ (wherein Me represents a methyl group) was used. Manufactured. When the rate of change in viscosity of this composition after 3 hours was measured in the same manner as above, the rate of change in viscosity was 210%. Further, for comparison, the room temperature-curable organopolysiloxane composition was prepared in the same manner as above except that methylvinyldimethoxysilane was used in place of the vinylalkoxy-functional organosilicon compound obtained in Example 1. Was manufactured. When the viscosity change rate of this composition after 3 hours was measured in the same manner as above, the viscosity change rate was 101% or less. From the above, it was found that the vinylalkoxy-functional organosilicon compound of the present invention obtained in Example 1 has a very high condensation reactivity with silanol groups.

[0012]

INDUSTRIAL APPLICABILITY The vinylalkoxy-functional organosilicon compound of the present invention is a novel compound having a vinyl group and an alkoxy group having a high condensation reactivity with a silanol group, and the production method of the present invention is It is characterized in that it can efficiently produce various vinylalkoxy-functional organosilicon compounds.

[Brief description of drawings]

FIG. 1 is an infrared absorption spectrum chart of the vinylalkoxy-functional organosilicon compound produced in Example 1.

2 is a ¹ H-nuclear magnetic resonance spectrum chart of the vinylalkoxy functional organosilicon compound prepared in Example 1. FIG.

FIG. 3 is an infrared absorption spectrum chart of the vinylalkoxy-functional organosilicon compound produced in Example 2.

FIG. 4 is a ¹ H-nuclear magnetic resonance spectrum chart of the vinylalkoxy-functional organosilicon compound prepared in Example 2.

Claims (3)

[Claims] 1. A general formula: (In the formula, R is an alkyl group having 1 to 4 carbon atoms, and a
Is 1 or 2. ) A vinylalkoxy-functional organosilicon compound represented by: 2. The vinylalkoxy-functional organosilicon compound according to claim 1, wherein R is a methyl group. 3. The method for producing a vinylalkoxy-functional organosilicon compound according to claim 1, wherein the syn-divinyltetramethyldisiloxane and vinyltrialkoxysilane are subjected to a re-equilibration reaction in the presence of an acidic catalyst.