JPH03190931A - Production of titanosiloxane polymer - Google Patents

Abstract

PURPOSE:To obtain the subject polymer, capable of readily preparing raw materials, easily handleable using simple reaction operation and useful as inorganic fiber, etc., by reacting a specific Si-containing starting substance with a Ti-containing starting substance in a specified proportion. CONSTITUTION:The objective polymer obtained reacting (A) a solution containing a partial hydrolyzate of a tetra-alkoxysiane having 1-4C alkoxy groups as a silicon-containing starting substance with (B) a solution containing bisacetylacetonatotitanium diisopropoxide and/or bisethylacetoacetatotitanium diisopropoxide as a titanium-containing starting substance at 0.5-20.0 atomic ratio of Si/Ti. Furthermore, the hydrolyzate of the component (A) is preferably obtained by partially hydrolyzing a 1-4C tetra-alkoxysilane at -50 to +50 deg.C under conditions so as to provide 1.5-4.0 molar ratio of water/the aforementioned silane.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing a titanosiloxane polymer. The titanosiloxane polymer obtained by the present invention can be further subjected to hydrolysis and thermal decomposition reactions to become an inorganic oxide cured product consisting of titanium atoms, silicon atoms, and oxygen atoms. Used as a raw material for adhesives, inorganic binders, etc.

[Prior Art] As a method for producing a titanosiloxane polymer, which is a precursor of a 5i02-Ti02-based inorganic oxide cured product, the following method is conventionally known.

(i) A method in which silicic acid extracted in tetrahydrofuran (THF) is reacted with titanium bisacetylacetonate diisopropoxide (see JP-A-63-56529 and JP-A-63-56530).

(11) Method of co-hydrolyzing tetraethoxysilane and titanium tetraisopropoxide (Ceramics Association Journal Vol. 84, pp. 614-618, Vol. 85, pp. 308-3
(See page 09).

[Problem to be solved by the invention] However, in the method (1) above, THF of silicic acid
Because it undergoes an extraction process, it is not suitable for continuous industrial production. That is, by extracting silicic acid into THF, the T of silicic acid is
In order to prepare an HF solution, it is necessary to go through processes such as neutralization of sodium metasilicate, extraction with THF, salting out, liquid separation, drying, and filtration, and furthermore, during this process, contamination of chloride ions and sodium ions is avoided. This makes industrialization difficult. In addition, method (i) has the disadvantage that if the atomic ratio in the raw material components is 4 or more, it becomes difficult to control the reaction, resulting in gelation.

On the other hand, in the method (ii) above, the titanosiloxane polymer produced by cohydrolysis of TeI-laethoxysilane and titanium tetraisopropoxide is extremely unstable and the condensation reaction easily proceeds. Prone to gelation. For example, since the pot life of this titanosiloxane polymer is within about 30 minutes, it is difficult to provide it as an industrial product. Therefore, it is difficult to use the titanosiloxane polymer obtained by the method (N) as a raw material for inorganic fibers, paints, adhesives, binders, etc.

Therefore, the object of the present invention is to eliminate the drawbacks of the above-mentioned prior art, and (a) prepare raw materials easily and have high purity raw materials obtained.

(b) Raw materials are easy to handle.

(c) The reaction operation (method) is simple, and the copolymerization reaction is easy to control.

(d) A titanosiloxane polymer that is highly stable against gelation due to self-condensation and has a long pot life can be obtained.

(e) Even if the atomic ratio of Si/Ti in the raw material components is 4 or more, titanosiloxane polymers that are stable against gelation due to self-condensation can be obtained, and as a result, a wide range of 3iQ2/TiO
A cured inorganic oxide having a composition range of 2 is obtained.

An object of the present invention is to provide a method for producing a titanosiloxane polymer having the following advantages.

[Means for Solving the Problems] The above object is achieved by using a solution containing a partial hydrolyzate of tetraalkoxysilane whose alkoxy group has 1 to 4 carbon atoms as a silicon-containing starting material, and a solution containing a partial hydrolyzate of tetraalkoxysilane whose alkoxy group has 1 to 4 carbon atoms; A solution containing titanium acetylacetonate diisopropoxide and/or titanium bisethylacetoacetate diisopropoxide is added to the S in the above two starting materials.
The atomic ratio of i/Ti is 0. This is achieved by the method for producing a titanosiloxane polymer of the present invention, which is characterized by reacting the silicon-containing starting material and the titanium-containing starting material by mixing them in a ratio of 5 to 20.0. Ta.

The present invention will be explained in detail below.

In the method for producing a titanosiloxane polymer of the present invention, a partial hydrolyzate of tetraalkoxysilane whose alkoxy group has 1 to 4 carbon atoms is used as a silicon-containing starting material, and bisacetyl is used as a titanium-containing starting material. Titanium acetonate diisopropoxide and/or titanium bisethylacetoacetate diisopropoxide are used, the former silicon-containing starting material, i.e. a partial hydrolyzate of tetraalkoxysilane, having the general formula (I) Si
(OR) t,...(1) (in the formula, R has 1 carbon number
- 4 alkyl groups) in a mixed solvent of water and an organic solvent such as methanol or ethanol such that the molar ratio of water/tetraalkoxysilane is 1.5 or more and less than 4.0. It is preferable to obtain it by partial hydrolysis under such conditions. During this hydrolysis, the temperature of the reaction solution was -50°C.
It is preferable to set the temperature in the range of ~+50°C1, particularly 20~+25°C.

Also, during hydrolysis, approximately 0%
．． When hydrochloric acid or acetic acid is added in an amount of about 1 molar amount, hydrolysis is effectively carried out.

The partial hydrolyzate of tetraalkoxysilane has the general formula (
II) S i (OH) m (OR) 4-m-(II)
(wherein, R is the same as defined in general formula (I),
(m is an integer of 1, 2, or 3), or the reaction with the titanium-containing starting material described in detail below is carried out smoothly, and the desired properties (composition, molecular weight, solvent solubility, self-condensation stability,
In order to efficiently produce a titanosiloxane polymer having threadability), the general formula (m) ? 1 H-0-(-3i -〇)7-H...(II[)
OH (wherein R is the same as defined in general formula (I),
n is an integer of 1 or 2 or more. ), a partial hydrolyzate of tetraalkoxysilane (n = 1) or its low polymer (n≧2) is used as titanium chelate-1, which will be described later.
It is preferable to react with

That is, in the compound represented by general formula (III), each of the two hydroxyl groups reacts with two reaction sites of the titanium-containing starting material described below to form a chain substance, and the remaining one reacts with the two reaction sites of the titanium-containing starting material. A titanosiloxane polymer having desired physical properties (solvent solubility, self-condensation stability, stability in solution, stringability) can be obtained by hydroxyl groups forming hydrogen bonds with other chain substances, for example. It will be done. In order to obtain a silicon-containing starting material containing a large amount of the compound of general formula (m), a water/tetraalkoxysilane molar ratio of about 2.5 to about 3.5 is used at a temperature of 0 to +20°C. is preferred.

In the method for producing a titanosiloxane polymer of the present invention, a titanium-containing starting material is used together with the silicon-containing starting material. Limited to titanium diisopropoxide.

These titanium-containing starting materials may be prepared in advance, or titanium tetraisopropoxide may be used.
The product obtained by reacting about twice the molar amount of acetylacetone or ethyl acetoacetate in a solvent such as 2-propatol may be used as it is in the reaction with the silicon-containing starting material without isolation.

In the reaction between a silicon-containing starting material and a titanium-containing starting material, the atomic ratio of 3i/Ti in both starting materials is 0.
It is necessary to mix both so that it becomes 5 or more and 20.0 or less. The reason is that the Si/Ti atomic ratio is 0. 5
If it is less than 100%, spinnability is obtained, but crystallization tends to occur during heat treatment, and the strength and heat resistance of the inorganic oxide cured product including the finally obtained inorganic fibers are low, and Si/
When the atomic ratio of Ti exceeds 20.0, it is difficult to obtain a titanosiloxane polymer with good stability in solution;
．． If it is in the range of 5 or more and 20.0 or less, a titanosiloxane polymer that exhibits spinnability will be obtained, and the inorganic oxide cured product including the inorganic fibers finally obtained will have high strength and high heat resistance. Because it will be. In the method of the prior art (i) above, there was a problem that gelation occurred when the Si/Ti atomic ratio was set to 4 or more, but in the method of the present invention, Si/Ti
There is an advantage that a desired titanosiloxane polymer can be obtained even if the atomic ratio of Ti is set to 4 or more and 20 or less.

The reaction is preferably carried out at room temperature to the reflux temperature of the solvent for 0.5 to 3 hours, particularly about 1 hour.

According to the method of the present invention, an acetylacetonate or ethyl acetoacetate group is bonded to a titanium atom as a side chain group, and the main chain is a titanosiloxane bond (Ti-0-3i
) is produced. The NMR spectrum of acetylacetonate titanosiloxane polymer shows approximately 2.
There are peaks based on acetylacetone groups at 0 ppm and about 5.2 ppm, and peaks at about 3.2 ppm. A peak based on silanol groups was observed at 4 ppm, while the NMR spectrum of the ethyl acetoacetate titanosiloxane polymer had a peak of about 1.
Peaks based on ethyl acetoacetate groups are observed at 2 ppm, about 1.8 ppm, about 4.4 ppm, and 0 about 4.7 ppm, and a peak based on silanol groups is observed at about 3.4 ppm.

The obtained titanosiloxane polymer is obtained as a highly viscous solution by concentrating the solution of the reaction mixture. This highly viscous solution exhibits spinnability and becomes a spinning solution for precursor fibers of 5iQ2-T i 02-based inorganic fibers.

Alternatively, after dissolving the above-mentioned highly viscous solution in acetone, a large amount of hexane can be added to separate and collect the resulting precipitate to form a powdery substance. This powdery substance is dissolved in a solvent such as methanol, ethanol, acetone, chloroform, etc., and the dissolved substance exhibits spinnability and becomes a precursor of 5i02-Ti02-based inorganic fibers.

When dissolved in a solvent, the titanosiloxane polymer obtained by the method of the present invention shows little change in viscosity over time, has a long pot life, can be stored for a long time, and is suitable for industrial use.

In addition, the titanosiloxane 1-sane polymer obtained by the method of the present invention is soluble in various organic solvents, so when used as a coating agent, adhesive, or binder, for example,
Another advantage is that it dries quickly and requires less time for coating, adhesion, and bonding.

[Example] The present invention will be further explained below based on Examples.

Example 1 To a solution of tetraalkoxysilane mixed with 50 ml of tetraethoxysilane, 1.87 g of water and 0.83 g of 6N hydrochloric acid (0.15 mol as H2O, H
0 as CI. 0 0 5 mol) and methanol 5
A partial hydrolysis reaction was performed by adding a mixed solution of 0ml and 0ml at 0°C. The molar ratio of water/te)-laethoxysilane was 3/1. After the end of the heat generation, add 18.2 g (0.
05 mol) isopropyl alcohol solution containing 24
．． Added 3g. Based on the amounts of tetraethoxysilane and bisacetylacenate titanium diisopropoxide used, the Si/Ti atomic ratio was 21/1. A reaction mixture was obtained by reacting for 1 hour at the reflux temperature of the solvent. When this reaction mixture was concentrated, a highly viscous solution was obtained, and when a glass rod was brought into contact with this solution and pulled up, it exhibited stringiness, and it became clear that it could be used as a precursor for Si02-Ti02-based inorganic fibers. Separately, 1 g of the above concentrated solution was taken, dissolved in 10 ml of acetone, and then 50 ml of hexane was added to form a precipitate.

This precipitate was collected and dried to obtain 0.5 g of powder. This powder was soluble in methanol, ethanol, acetone, chloroform, etc., and insoluble in benzene, hexane, etc. Solutions dissolved in soluble solvents such as methanol also showed stringiness. In addition, solutions dissolved in soluble solvents have little change in viscosity over time and have a long pot life.
It has become clear that it can be preferably used as a coating agent, adhesive, or binder.

When the NMR of the above powder was measured, it was found to be 2.0 ppm and 5.
．． A peak based on acetylacetone group at 2 ppm,
3. At 4 ppm, 3 peaks were observed based on silanol groups. When the IR spectrum of this powder was measured, silanol groups at 3400 cm and 1 peak were observed at 3400 cm.
Acetylacetone groups at 580 and 1520 cm, 1
10Cl~]. Si-OSi bond at 000cm-1, 9
Absorption based on Si-〇-Ti bond was observed at 30 cm-1.

Example 2 Two types of reactions were carried out in the same manner as in Example 1, except that the same raw materials as those used in Example 1 were used and the partial hydrolysis reaction and polymerization reaction were carried out under the conditions listed in Table 1. A mixed solution was obtained. Table 1 shows the properties of the solution obtained by concentrating these reaction mixtures, the fiber length as a measure of spinnability, and the yield of the titanosiloxane polymer recovered.

From Table 1, Experiment No. 1 obtained by the method of the present invention. Titanosiloxane polymers 1 and 2 have stringiness, so S
It can be a precursor of i02-Ti02-based inorganic fibers. Although not shown in the table, it has been confirmed that it is soluble in various solvents, has little change in solution viscosity over time, and has a long pot life, so it is preferably used as a coating agent, adhesive, or binder. be done.

(Margin below) Table 1 5 *1...TE01 indicates tetraethoxysilane.

*2...Fiber length (cm) was determined by pulling a glass rod out of the concentrate at a constant speed.

*3... Yield indicates the weight (g) of the titanosiloxane polymer obtained by dissolving 1 g of the concentrate in 10 ml of acetone and adding this to 50 ml of hexane.

6 Example 3 Three reaction mixtures were carried out in the same manner as in Example 1, except that the same raw materials as those used in Example 1 were used and the partial hydrolysis reaction and polymerization reaction were performed under the conditions shown in Table 2. I got the liquid.

Table 2 shows the properties of the solution obtained by concentrating these reaction mixtures, the fiber length as a measure of spinnability, and the yield of the recovered titanosiloxane polymer.

From Table 2, experiment No. 11 obtained by the method of the present invention
．． It was confirmed that titanosiloxane polymers Nos. 12 and 13 both had a fiber length of -00 cm and had stringability. Although not shown in the table, it was confirmed that it is soluble in various solvents, has little change in solution viscosity over time, and has a long pot life.

Table 2 (blank below) 7 8 Example 4 Unlike Example 1, tetramethoxysilane was used as the tetraalkoxysilane. Two types of reaction mixtures were obtained in the same manner as in Example 1, except that 8 ml (0.05 mol) was used and the partial hydrolysis reaction and polymerization reaction were carried out under the conditions shown in Table 3. Table 3 shows the properties of the solution obtained by concentrating these reaction mixtures, the fiber length as a measure of spinnability, and the yield of the recovered titanosiloxane polymer.

From Table 3, Experiment No. 2 obtained by the method of the present invention
It was confirmed that the titanosiloxane polymers Nos. 1 and 22 had stringability.

Although not shown in the table, it was confirmed that it is soluble in various solvents, has little change in solution viscosity over time, and has a long pot life.

Table 3 (Margin below) *1a...TM01 indicates tetramethoxysilane.

For *2 and *3, see footnotes in Table 1.

90 Example 5 Bisethyl acetoacetate titanium diisopropoxide was added to 18. Two reaction mixtures were obtained in the same manner as in Example 1, except that the partial hydrolysis reaction and polymerization reaction were carried out under the conditions shown in Table 4 using an isopropyl alcohol solution containing 2 g (0.05 mol). . Table 4 shows the properties of the solution obtained by concentrating these reaction mixtures, the fiber length as a measure of spinnability, and the yield of the recovered titanosiloxane polymer.

From Table 4, Experiment No. 3 obtained by the method of the present invention
It was confirmed that the titanosiloxane polymers Nos. 1 and 32 had stringability.

Although not shown in the table, it was confirmed that it is soluble in various solvents, has little change in solution viscosity over time, and has a long pot life.

Continuous long fibers of titanosiloxane polymer having a diameter were obtained.

(Left below) Also, Example 1. 2. 3. When the titanosiloxane polymers exhibiting spinnability in 4 and 5 were subjected to normal dry spinning, fibers of 5 to 100 microns were obtained. (a) The titanium-containing starting material, bisacetylacetonate titanium diisopropoxide or bisethyl acetate titanium diisopropoxide, is less hydrolyzable than the conventionally used titanium diisopropoxide. Low and easy to handle.

(b) It is difficult to control the reaction in a method of co-hydrolyzing tetraalkoxysilane and titanium tetraisopropoxide, but in the present invention, a partial hydrolyzate of tetraalkoxysilane, which is a silicon-containing starting material, and the above titanium-containing A titanosiloxane polymer can be obtained by a simple operation of mixing the starting materials in a solvent and stirring or heating to reflux.

(c) In the co-hydrolysis of tetraalkoxysilane and titanium tetraisopropoxide, single condensation occurs due to the difference in the hydrolysis rate of each alkoxide, resulting in a block copolymer and a heterogeneous product. In the invention, after partial hydrolysis of tetraalkoxysilane, a titanosiloxane polymer is obtained by a dealcoholization reaction with bisacetylacetonate titanium diisopropoxide or bisethylacetoacetate, which has relatively high copolymerizability. A titanosiloxane polymer that is homogeneous at the molecular level can be obtained.

(d) In the titanosiloxane polymer obtained by the present invention, a ligand is bonded to the titanium atom of the titanosiloxane bond in the main chain, and an alkoxy group is bonded to the silicon atom as a side chain.・Compared to titanosiloxane polymers obtained by cohydrolysis of laalkoxysilane and titanium tetraisopropoxide or titanosiloxane polymers obtained using silicic acid, it has stringability but is stable against self-condensation. Highly sexual.

(e) By changing the amount of water added to the tetraalkoxysilane during partial hydrolysis of the tetraalkoxysilane and the hydrolysis temperature, Si/Ti of 0.5 or more - 20 or less can be obtained by changing the amount and hydrolysis temperature.
A titanosiloxane polymer having stringability with an atomic ratio is obtained.

By dry spinning it and using it as a precursor of TiO2-8i02 fiber, TiO2-8 with a wide range of composition ratios can be produced.
iO2 fibers are obtained.

It is also preferably used as a raw material for coating agents, adhesives, and binders.

It has technical effects such as

Claims (3)

[Claims] (1) A solution containing a partial hydrolyzate of tetraalkoxysilane whose alkoxy group has 1 to 4 carbon atoms as a silicon-containing starting material, and bisacetylacetonate titanium diisopropoxide and/or as a titanium-containing starting material. or bisethyl acetoacetate titanium diisopropoxide.
A method for producing a titanosiloxane polymer, which comprises reacting the silicon-containing starting material and titanium-containing starting material by mixing them in such a proportion that the atomic ratio of i is 0.5 or more and 20.0 or less. . (2) The partial hydrolyzate of tetraalkoxysilane as a silicon-containing starting material has an alkoxy group having 1 to 1 carbon atoms.
Obtained by partially hydrolyzing four tetraalkoxysilanes at a temperature of -50 to +50°C under conditions such that the water/tetraalkoxysilane molar ratio is 1.5 or more and less than 4.0. The method according to claim (1). (3) A titanosiloxane polymer obtained by the method according to claim (1) or (2).