JPS59108033A - Preparation of ladder-type polyphenylsiloxane having high molecular weight - Google Patents

Abstract

PURPOSE:To prepare the titled siloxane soluble in a solvent, having excellent heat resistance, hydrolysis resistance, etc., and suitable as an insulation material, etc., by condensing a specific phenylsiloxane oligomer having ladder structure in the presence of a fluorine compound as a catalyst. CONSTITUTION:The objective siloxane having a molecular weight (Mw) of preferably 10<4>-10<7> is prepared by condensing (A) a phenylsiloxane oligomer having ladder structure and having (i) terminal hydroxyl group or (ii) terminal cage group (silsesquioxane-type) in the presence of (B) a fluorine compound [preferably an alkali or alkaline earth metal fluoride such as LiF, KF, CsF, CaF, etc. or a quaternary ammonium fluoride of (CH2H5)4NF, C6H5N(CH3)3F, etc.] as a catalyst.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is soluble in solvents, has heat resistance, hydrolysis resistance,
Polyphenylsiloxane with a ladder structure that has excellent electrical insulation properties and strong mechanical strength as an insulating material and a heat-resistant coating material. This relates to a manufacturing method.

According to JP-A No. 57-18729, as a method for producing a high molecular weight terminal hydroxy ladder type polyphenylsiloxane represented by formula 1 below, a terminal hydroxy ladder type polyphenylsiloxane intermediate is dehydrated using a carbodiimide as a condensing agent. A condensation method has been proposed. According to the inventors' reexamination of this conventional method, a terminal hydroxy ladder type phenylpolysiloxane with a high molecular weight and residual hydroxyl groups at the terminals was obtained. The resulting membrane is
It is not fully satisfactory when viewed as a membrane material that has a membrane strength that can withstand practical use.

Further, a polymer having a terminal octaphenylsilsesquioxane structure represented by the following formula (1) is disclosed as a terminal cage type phenylpolysiloxane in Japanese Patent Publication No. 40-15989, USP 3,0
It is described in 1S No. 686, etc., and has been known for a long time as a heat-resistant polymer. According to the description in Japanese Patent Publication No. 40-15989, this polymer is 06 H,
From an intermediate obtained by hydrolyzing S i C1, using an alkaline catalyst such as caustic potash.

Octaphenylsilsesquioxane is produced, isolated, and then ring-opening polymerized again using an alkaline catalyst such as caustic potash at a high temperature. When the present inventors tried this method again, they found that it did indeed give a high molecular weight product, but in order to do so, ring-opening polymerization had to be carried out under conditions close to solid-state polymerization, and in some cases gel In order to improve reproducibility, the molecular weight distribution should be 1.
A wide distribution of 0 or more may occur. The intended use of this material is generally to dissolve it in an appropriate solvent and apply it in a solution state, or to use it in the form of a film formed by a casting method. The amount of low molecular weight substances contained in the water also increased.

This results in a decrease in heat resistance and film strength. Furthermore, the film obtained thereby has drawbacks such as containing fish eyes, and this method is not preferred as an industrial manufacturing method.

Furthermore, in order to improve the wide molecular weight distribution which is a drawback of this conventional method, in JP-A-57-10627,
A method has been proposed in which low molecular weight substances are extracted using a Soxhlet type extractor using acetone as an extraction solvent to obtain a ladder type polyphenylsiloxane with a narrowly fractionated molecular weight distribution, but polymer extraction is not a practical manufacturing method. However, it is not a preferable method because it not only complicates the process (but also uses highly flammable acetone).

In view of the fact that the known methods as illustrated above have many drawbacks and cannot produce industrial materials, the present inventors have developed a homogeneous material that is soluble in solvents and has strong film strength when formed into a film. For the purpose of producing ladder type polyphenylsiloxane.

As a result of extensive research, we have discovered a method for producing the high molecular weight ladder type polysiloxane of the present invention.

That is, the present invention is obtained by hydrolyzing C6H, S i C4. The present invention relates to a terminal hydroxy ladder type oligosiloxane, or a method for producing a ladder type polyphenylsiloxane having a molecular weight that is considered to be a terminal cage type oligosiloxane.

The molecular weight (M
w) and molecular weight a (]VIw/Mn) were prepared using a high performance liquid chromatograph HLC-802UR manufactured by Toyo Soda Co., Ltd. using tetrahydrofuran (THF) as a solvent, and using TSK standard polystyrene also manufactured by Toyo Soda Co., Ltd. This is a relative value obtained from the calibration Hi. The molecular weight (Mw) and molecular leaf distribution (Mw/Mn) shown hereinafter in this specification are values measured by Kenpo.

In addition, the heat resistance temperature shown in this specification refers to the thermal decomposition temperature of the polymer (as measured by the thermal wheel quantity measuring device MDT-20B, Tc-20 manufactured by Shimadzu Corporation), since the ladder type polyphenylsiloxane does not have meltability. positive amount decrease) start @ degree.

Furthermore, the film strength shown in this specification is based on a solution of molecular weight ladder type polyphenylsiloxane dissolved in toluene.

A film formed on a glass plate by the casting method was used as a sample, and a Tensilon tensile tester manufactured by Toyo Baldwin was used.

A tensile test was conducted in accordance with ASTM D882-61T, and the strength of the film was calculated using a conventional method.

The terminal hydroxy ladder type phenylsiloxane oligomer that can be used in the method of the present invention includes, for example, Eva CeHsSiC.
The molecular weight (Mw) easily obtained by hydrolysis in toluene at room temperature is 10&fJ to 8,000, which is similarly shown by the above formula 1. In addition, the ladder structure terminal cage type phenylsiloxane oligomer can be easily obtained by heating the terminal hydroxy ladder type polyphenylsiloxane intermediate represented by formula 1 above using a fluorine compound as a catalyst, and is a solid with a molecular weight (Mw). 1000-20
．． OO'O, which is also shown in the formula (2) above. Further, as is clear from the above, the raw material oligomer may be hydroxyl-terminated, cage-terminated, or a mixture of both, or may have different ends in the same molecule.

As a catalyst for the fluorine thread used in the method of the present invention, f@,
LiF.

Fluorine compounds of alkali metals or alkaline earth metals, such as NaF, KF, C5F-CaF2, (CHa)
4NF, (C2H5 NF.

(C,H full NF, (C4H9)4NF, C6H3
N(CH3)8F, CIIHa・CB2 N(CHa
) 3 F and other quaternary ammonium fluorides,
CsF is preferred. The amount of the catalyst used is from 0.00% to 5% by weight based on the raw material silane oligomer, preferably from 0.0.01 to 1M.

The solvent used in the method of the present invention may be any solvent as long as it can serve as a solvent for the produced polymer. In general, aromatic hydrocarbons such as benzene, toluene, xylene, diphenyl, diphenyl ether, N-7+ tilpyrrolidone, 0-dichlorobenzene, acetophenone, ketones, ethers, heterocyclic compounds, etc. can be used. These solvents can be used alone or in combination of two or more. Also, what is the concentration of polyphenylsiloxane, which is a raw material intermediate?

Although it varies depending on the structure of the raw materials and the method of operation, the amount of the final reaction product polymer ranges from 50 to 90% by weight, preferably 60% by weight.
It is in the weight range of 5 to 85. At a concentration below 50 weight, it is difficult to obtain a polymer with the desired high molecular weight, and at a concentration above 90 weight, it is close to solid phase polymerization, making it difficult to maintain system uniformity.
This method is difficult to recommend as an industrial manufacturing method due to poor reproducibility.

The high polymerization V reaction of the present invention can be carried out at a temperature of 150 to 300°C, or if the boiling point of the solvent used is lower than the reaction temperature, the reaction can be carried out under pressure. A suitable reaction temperature is 200-250°C.

The reaction time of the high polymerization reaction varies depending on the reaction temperature, the type and amount of catalyst, etc., and requires a long time at low temperatures, but the Hontaka Teigo reaction is a relatively rapid reaction, and for example, CsF is used. In this case, at a reaction temperature of 250°C, about 1 hour is sufficient.

After the reaction is completed, the reaction solution is added to a large amount of methanol under stirring to obtain a ladder-type polyphenylsiloxane having a single molecular weight as a precipitate. The molecular weight of the ladder type polyphenylsiloxane obtained here is 104 to 107.
is within the range of

Ladder type polyphenylsiloxane obtained by the present invention.

It is soluble in general-purpose solvents such as organic tohabenzene, toluene, xylene, chloroform, trichloroethylene, and tetrahydrofuran, and the infrared absorption spectrum (IR) of the film formed by the casting method shows 3500 cr.
No absorption of 10H of n-' was observed, and it is thought that the terminals are mainly cage-shaped. However, its cage-shaped structure is
The octasilsesquioxane type is limited, and there may also be the hexasilsesquioxane type and other cage types.

Solid polyphenylsiloxane obtained by non-invention.

Even if left in the air for a long period of time, no change in properties was observed.

In addition, there was no change in storage stability in the form of a solution containing a solvent, and the storage stability was extremely excellent.

The present invention will be explained below with reference to Reference Examples and Examples, but the present invention is not limited to these Examples.

Reference Example 1 Production of hydroxy-terminated ladder type polyphenylsiloxane intermediate Phenyltrichlorosilane CCeHsSiC&) 20
[1 g (0.95 mol) and 400 g of toluene in a stirrer and a cooler.

Temperature H ↑, put into a reactor with a dropping funnel and soak in a water bath for 2 hours.
Cool to below 0°C. While stirring and cooling to maintain the reaction temperature below 20° C., 52 g (2.9 mol) of ion-exchanged water is added dropwise from the dropping funnel over 60 minutes to effect hydrolysis. Thereafter, the reaction was continued for another 30 minutes at the same temperature to complete the hydrolysis. Then, 270 g of ion-exchanged water is added and the toluene layer is separated. The toluene layer is repeatedly washed with ion-exchanged water until it becomes neutral. Thereafter, the toluene solution was dried over anhydrous sodium sulfate, the toluene was distilled off, and the residue was dried under reduced pressure. The obtained compound is a white powder, and its IR is 3250.3625 cm-
' showed OH absorption, and it was confirmed that it had a hydroxy'/terminal pad type polyphenylsiloxane structure. The white powder obtained here was dissolved in tetrahydrofuran and the molecular weight (Mw) was measured and found to be 6900.
Met.

Example 1 10 g of the hydroxy-terminated ladder type polyphenylsiloxane intermediate obtained in Reference Example 1 was dehydrated using a reflux condenser and a stirrer.

Place in a reactor with a thermometer and add 50% of toluene as a solvent.
g.

2.5 g of diphenyl ether was added and dissolved to form a homogeneous solution.

C5F10 was added as a high polymerization reaction catalyst. The water produced by heating the reaction mixture is distilled out of the system as an azeotrope with toluene, and the reaction is continued while the temperature is increased while toluene is distilled off. After distilling off the toluene, the temperature was set at 250°C.

The straw bundle reaction was carried out for 60 minutes with stirring, and after one reaction was completed, the mixture was cooled and 91% of toluene was added to uniformly dissolve one reaction solution. The toluene solution was dropped into a large amount of methanol with stirring to precipitate a polymer with a high degree of polymerization. The precipitate was separated and dried under reduced pressure (60°C).The resulting polymer was a white powder, yield 9. i g, dissolved in an i-medium KJJ- such as benzene, toluene, xylene, etc. The average molecular weight (Mw) measured by dissolving in THF was 1.2X106. Molecular weight distribution (
Mw/Mn) is 6.6.

Heat resistance was 520°C. In addition, a film formed by dissolving it in toluene and using a casting method has been recognized as an extremely homogeneous, colorless, transparent, and strong film, and when cut from this film and subjected to a tensile test, /mm
It had a tensile strength of 2. Further, no OH was observed in the IR spectrum.

Reference Example 2 Production process of terminal cage type ladder polyphenylsiloxane 10 g of terminal hydroxy ladder type polyphenylsiloxane obtained in Reference Example 1 was placed in a reactor equipped with a dehydration reflux condenser, a stirrer, and a thermometer, and 50 g of toluene was added and dissolved to form a homogeneous solution. CsFlo as condensation catalyst
After adding 1.0 mg of water and heating the resulting water to the outside of the thread as an azeotropic mixture with toluene, the reaction was carried out for 2 hours with stirring.

After the reaction was completed, the reactants were dropped into a large amount of methanol to precipitate a polymer, and after separation, the mixture was dried under reduced pressure at 60°C. The obtained polymer was a white powder, and the yield was 94 g.

The average molecular weight (MW) measured by dissolving in THF is 780
0, no OH absorption was observed by IR, and the ends were cage-shaped.

Example 2 94 g of the end-cage ladder polyphenylsiloxane obtained in Reference Example 2 was placed in a reaction vessel equipped with a reflux condenser, a stirrer and a thermometer, and 2.0 g of diphenyl ether was added as a solvent.
1. 10 ml of CsF was added as a ring-opening polymerization catalyst. This reaction mixture was heated to 250° C. and reacted for 30 minutes under stirring and reflux. After the reaction was completed, the mixture was cooled and 90.9 g of toluene was added to dissolve the mixture uniformly. The solution was dropped into a large amount of methanol to precipitate the polymer, and then the polymer was separated and dried under reduced pressure.

The obtained polymer was a white powder, and the yield was 90 g. The average molecular weight (Mw) of this polymer is 1.6
The x10' molecular weight distribution was 2.7, and the tensile strength of the film formed from toluene was 3.8 Yu/12.

Comparative Example 1 A high polymerization reaction was carried out in the same manner as in Example 2 except that xoasome was used instead of CsF and the reaction was carried out for 4 hours to obtain a polymer. The average molecular weight (Mw) of this polymer was 3×105 molecular weight distribution was 8.2, and the heat resistance was 440°C. The tensile strength of the film formed by dissolving it in toluene and casting by a casting method was 1.1 kg/w', and fish eyes were observed in the film.

In the method of Example 1, the same conditions and operations were carried out except that the amount of the catalyst for high polymerization and the amount of i-enyl ether were changed. The properties of the resulting polymer are shown in Table-
Examples 7 to 12 In the method of Example 1, various other fluorine compounds were used instead of CsF as a catalyst for high polymerization. Except for this, the experiment was carried out under the same conditions and operations. The results are shown in the table-
As shown in 2.

9 1　Fuchi - 1111 colors

Claims (1)

[Scope of Claims] (2) A polymerization method characterized by condensing a terminal hydroxy type or terminal cage type (silsesquioxane type) 7-enylsiloxane oligomer having a ladder structure in the presence of a fluorine compound as a catalyst. Manufacturing method 2 of molecular weight ladder type polyphenylsiloxane Catalyst is LiF, KF, NaF, CsF, C
The manufacturing method according to claim 1, wherein the fluorine compound is an alkali metal or alkaline earth metal fluorine compound represented by aF, etc. 8. The catalyst is (C2H5)4NF, C6H5N(C
H3) The manufacturing method according to claim 1, which is a quaternary ammonium fluoride represented by 3F or the like. The manufacturing method according to claim 1 or 2, wherein the molecular weight (MW) is 104 to 107.