JPS59524B2 - Method for producing silicone-modified polyoxyalkylene - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing silicone-modified polyoxyalkylenes having excellent curing properties.

Conventionally, a silane compound H-Si(
R)b(X)3-b (R in the formula represents an organic group, and X represents a group selected from a halogen atom, an alkoxy group, an acyloxy group, and a ketoxime group.

A method for producing polyoxyalkylene (a one-component room temperature curable silicon-terminated polymer) in which a silyl group is introduced at the end of the molecular chain by conducting an addition reaction with b is 0, 1 or 2 has been developed. (Refer to Japanese Patent Application Laid-open No. 156599/1983). However, in this type, when X is a halogen atom, the halogen is converted into the corresponding hydration compound by reacting it with an alcohol, an organic carboxylic acid, an amide, an acid amide, a dialkylhydroxylamine, or an oxime compound. It is necessary to use a decomposable group, and when X is a hydrolyzable group such as an alkoxy group, a metal salt of an organic carboxylic acid is used as a curing catalyst to obtain a room temperature curable composition. It is necessary to add a large amount of these ingredients, and adding such a large amount may affect the heat resistance of the cured product.
It has the disadvantage of impairing weather resistance.

Furthermore, if X is an acyloxy group, a strongly corrosive gas is generated during curing, and it is difficult to incorporate a filler with a base type into the composition.If X is an acid amide group, However, since the silane compound is unstable, there is a problem in that the addition reaction with the polyoxyalkylene having an allyl group at the end is difficult to proceed quantitatively.

The present invention eliminates such conventional drawbacks and cures! The purpose is to provide a method for producing silicone-modified polyoxyalkylene with improved properties, which has an unsaturated group at the end of the molecular chain represented by the formula (in which n is 0 or 1). , whose main chain consists essentially of chemically bonded repeating units of the formula (wherein R1 represents a divalent hydrocarbon group having 2 to 3 carbon atoms), with a molecular weight of 400 to 150
The following general formula (here, R2 and R4 are monovalent hydrocarbon groups, and R3 is Hydrogen atom or monovalent hydrocarbon group, A,
b, c are O〈a≦1, 0≦bku4, 0〈cku4, a+
This method is characterized in that hydrogen groups directly bonded to the silicon atoms of the organosilicon compound represented by b+c≦4) undergo an addition reaction in the presence of a platinum-based catalyst.

According to the method of the present invention, the unsaturated bond represented by formula (1) and the Si-H bond of the organosilicon compound represented by (1) quantitatively undergo an addition reaction, and at this time, the organosilicon compound Since the alkenyloxy group, which is another group in the polyoxyalkylene, exists stably without any problems such as decomposition or reaction, it is easy to create an organosilicon compound having an alkenyloxy group at the end of the molecular chain of polyoxyalkylene. The advantage is that a silicone-modified polyoxyalkylene with excellent curing properties can be obtained.

The present invention will be explained in detail below.

The unsaturated group-containing polyoxyalkylene, which is one of the raw materials used in the method of the present invention, has an unsaturated group represented by formula (1) at one or both ends of the molecular chain, and the main chain is essentially , consisting of chemically bonded repeating units represented by the formula (), where n is 0 or 1, and R in () is
1 represents a divalent hydrocarbon group having 2 to 3 carbon atoms, and examples of R1 include the following.

In addition, the repeating structure of oxyalkylene represented by formula () is not limited to only one type of R1, and may include a different type of group selected from the divalent hydrocarbon groups represented by R1 described above and an oxygen atom. For example, it may have a polyoxyethylene polyoxypropylene structure.

Such unsaturated group-containing polyoxyalkylenes are described, for example, in JP-A-50-156599 and JP-A-53-129.
It is described in detail in Publication No. 27 and Publication No. 53134095, etc., and any of the polyoxyalkylenes described in these publications can be used in the present invention, but those having a molecular weight of 400 to 15,000 are particularly preferred. .

Next, the organosilicon compound to be reacted with the unsaturated group-containing polyoxyalkylene needs to have a hydrogen atom directly bonded to a silicon atom and an alkenyloxy group in one molecule. , this is, for example, the general formula (ko\
R2 and R4 are monovalent hydrocarbon groups, R3 is a hydrogen atom or a monovalent hydrocarbon group, A, b, and c are O≦1, 0≦b≦4
, 0 x c x 4 and a+b+c≦4), and examples thereof include the silanes and siloxanes listed below.

However, in the following description, Me represents a methyl group, Et represents an ethyl group, and Ph represents a phenyl group (the same applies hereinafter). The desired silicone-modified polyoxyalkylene can be obtained by addition-reacting the unsaturated group-containing polyoxyalkylene and the above-mentioned organosilicon compound in the presence of a platinum-based catalyst, but the reaction of both raw materials at this time The molar ratio is calculated using the above formula (
The number of Si--H bonds in the organosilicon compound may be equal to one mole per mole of the unsaturated group represented by 1).
In order to carry out the addition reaction of the unsaturated groups in the unsaturated group-containing polyoxyalkylene as completely as possible, it is desirable to use an excess of the organosilicon compound, and the reaction temperature is
The temperature is preferably in the range of 0 to 150°C, particularly 40 to 120°C. Platinum-based catalysts used for this addition reaction include platinum metal, platinized activated carbon,
Examples include chloroplatinic acid, platinum alcohol compounds, platinum olefin complexes, platinum aldehyde complexes, and platinum ketone complexes.

Although the use of a solvent is not particularly required in this reaction,
If the starting material has a high viscosity and operations such as stirring are difficult, it is okay to use an inert organic solvent as appropriate, such as benzene, toluene,
Aromatic hydrocarbon solvents such as xylene, aliphatic hydrocarbon solvents such as hexane and octane, ethyl ether,
Examples include ether solvents such as butyl ether, ketone solvents such as methyl ethyl ketone, and halogenated hydrocarbon solvents such as trichloroethylene.

The silicone-modified polyoxyalkylene obtained by the method of the present invention is characterized in that it is rapidly cured by the action of moisture with a small amount of catalyst, and has no drawbacks such as corrosivity, toxicity, and odor. In particular, it is said that by adding a guanidyl group-containing compound, a cured product with excellent physical properties can be obtained without using a metal salt of an organic carboxylic acid that adversely affects the physical properties (heat resistance, weather resistance, etc.) of the cured product as a catalyst. It has notable advantages. Next, reference examples and examples of the present invention will be given.

Reference Example 1 Add acetone 3489 (6.0
mol), triethylamine 3039 (3.0 mol) and zinc chloride 19 were charged, and methyldichlorosilane 1259 (1.0 mol) was gradually added dropwise at room temperature.

The contents of the flask become pale and colored as the liquid is added, and the internal temperature reaches 3.
The temperature rose to 5°C. After dropping, stir at room temperature for 8 hours,
The mixture was further heated at 50°C for 1 hour.

After cooling and filtering, the filtrate was distilled and the boiling point was 53°C/
1039 fractions (products) of 133 mmHg were obtained.
This product was confirmed to be methyldiisopropenooxysilane by infrared absorption spectrum, gas chromatography, and elemental analysis (yield: 65%).

Reference Example 2 A reaction flask was charged with 516 g of diethyl ketone (660 mono(c)), triethylamine 3039 (3.0 mol) and zinc chloride 19, and methyldichlorosilane 1259 (1.0 mol) was prepared over 30 minutes at room temperature. was gradually added dropwise (almost no heat generation or endotherm was observed), then 50
Stirred at ℃ for 16 hours.

After cooling and filtering, the filtrate was distilled under reduced pressure to obtain 1281 fractions (products) with a boiling point of 85 C/13 mmHg. This product was confirmed by infrared absorption spectrum, gas chromatography, and elemental analysis to be an alkenyloxy group-containing silane represented by the formula.

Reference Example 3 In a reaction flask, acetone 1169 (2.0 mol), triethylamine 1519 (1.5 mol) and monochloride were added.
2 g of copper was charged, and 94 g (1.0 mol) of dimethylmonochlorosilane was added dropwise over 30 minutes at room temperature.
Heated at ~50°C for 8 hours.

After cooling and filtering, the filtrate was distilled to obtain 1109 dimethylmonoisoprobenoxysilane (yield 70%). Example 1 150 parts of polyoxypropylene (having an allyloxy group at both ends of the molecular chain and having a viscosity of 800 centistokes (average molecular weight 4200) at 25°C) was placed in a reaction flask.
18 parts of methyldiisopropenooxysilane obtained in Reference Example 1, 0.3 parts of isopropyl alcohol solution of chloroplatinic acid (2% by weight as platinum)
1 part and 200 parts of toluene were charged, and addition reaction was carried out at 9'C for 1 hour and then at 120°C for 2 hours while stirring.

After cooling, unreacted methyldiisopropenooxysilane was quantified by gas chromatography and the addition reaction rate was found to be 98%.

The alkenyloxy group-containing silicone-modified polyoxypropylene produced is shown by the formula, and has a viscosity of 970 centistokes (25°C), and the allyloxy group at the end of the polyoxypropylene has almost completely disappeared. was.

Example 2 In a reaction flask, 150 parts of polyoxypropylene similar to that used in the previous example, 20 parts of the alkenyloxy group-containing silane obtained in Reference Example 2, 0.3 part of chloroplatinic acid solution similar to that used in the previous example, and toluene were added. When 200 parts were charged and the addition reaction was carried out at 90°C for 1 hour with stirring and then at 120°C for 10 hours, the viscosity at 25°C was 950 centistokes.
-1V low. An alkenyloxy group-containing silicone-modified polyoxypropylene was obtained.

As a result of gas chromatography and quantitative determination of the allyl group at the end of polyoxypropylene, the addition rate was 82%. Example 3 A reaction flask containing an allyloxy group having an allyloxy group at both ends of the molecular chain and having a viscosity of 2200 centistokes at 25°C (
150 parts of polyoxypropylene with an average molecular weight of 6,000), 9 parts of dimethylmonoisopropenooxysilane obtained in Reference Example 3, and 0 parts of the same chloroplatinic acid solution used in Example 1.
．． 3 parts and 100 parts of toluene were charged, and an addition reaction was carried out at 40°C for 3 hours while stirring and then at 60°C for 8 hours, resulting in an alkenyloxy group-containing silicone having a viscosity of 3960 centistokes at 25°C. Modified polyoxypropylene was obtained.

The addition rate was 98%, and the 'allyl group at the end of the polyoxypropylene had almost completely disappeared. Example
4 In the reaction flask, a sample containing allyloxy groups at both ends of the molecular chain and having a viscosity of 2050 centistokes at 25°C (
Polyoxypropylene 150 with average molecular weight 5600)
18 parts of an alkenyloxy group-containing disiloxane represented by the formula
When the addition reaction was carried out at 10°C for 6 hours, an alkenyloxy group-containing silicone-modified polyoxypropylene represented by the formula and having a viscosity of 2630 centistokes at 25°C was obtained.

As a result of gas chromatography and quantitative determination of the allyl group at the end of polyoxypropylene, the addition rate was 89%.

Example 5 Polyoxypropylene 15 similar to that used in Example 4
0 parts, 28 parts of alkenyloxy group-containing cyclic siloxane represented by the formula, 0.2 parts of chloroplatinic acid solution similar to that used in Example 1, and 100 parts of toluene were added, and addition reaction was carried out at 100°C for 6 hours with stirring. When I let it go, 25
An alkenyloxy group-containing silicone-modified polyoxypropylene having a viscosity of 3250 centistokes at °C was obtained.

Claims (1)

[Scope of Claims] 1. Has an unsaturated group represented by the formula -(O)n-CH_2-CH=CH_2 (n in the formula is 0 or 1) at the end of the molecular chain, and the main chain is essentially Generally, it consists of chemically bonded repeating units represented by the formula -R^1O- (wherein R^1 represents a divalent hydrocarbon group having 2 to 3 carbon atoms) and has a molecular weight of 400 to 15,000. The following general formula ▲ has a hydrogen atom directly connected to a silicon atom and an alkenyloxy group in the double bond of an unsaturated group-containing polyoxyalkylene ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (here R^2 , R^4 is a monovalent hydrocarbon group, R^3 is a hydrogen atom or a monovalent hydrocarbon group, a, b, c are 0<a≦1
, 0≦b<4, 0<c<4, and a+b+c≦4) The hydrogen group directly bonded to the silicon atom of the organosilicon compound is subjected to an addition reaction in the presence of a platinum-based catalyst. A method for producing silicone-modified polyoxyalkylene.