JPH0333182B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to the production of high molecular weight organoaluminum polymers. In recent years, the emergence of high-strength, ultra-heat-resistant materials has been desired in various industrial fields, and alumina fibers, which are suitable for composite materials such as metals and ceramics, are attracting attention as one such material. A method by which precursor fibers made of organoaluminum polymers are fired has been attracting attention as an excellent method for producing alumina fibers. There was a lack of a manufacturing method. That is, it is already known that an organoaluminum polymer can be obtained by a condensation polymerization reaction of an organoaluminum compound and water, but depending on the known method, the general formula

An organoaluminum compound having the molecular structure of [formula] (residues X, Y, Z represent hydrogen, alkyl group, alkoxyl group,
Even if they are completely different residues or the same residue,
Furthermore, any two of residues X, Y, and Z may be the same residue, and the remaining residues may be different residues. ) and water to obtain a high molecular weight polymer suitable for molding into fibers, etc., through a condensation polymerization reaction. For this reason, the present presenters have conducted various studies on methods for obtaining high-molecular-weight organoaluminum polymers suitable for molding fibers, etc., and have found that 1 mole of organoaluminum compounds is For general formula
A high molecular weight organic aluminum compound suitable for forming fibers etc. by adding 1.1 to 10 moles of an organic acid represented by ROCH ₂ CH ₂ COOH (R represents an alkyl group having 1 to 5 carbon atoms). It was discovered that this can be obtained easily and efficiently. The present invention is based on the general formula

[Formula] In the production of an organoaluminum polymer by condensation polymerization reaction of an _{organoaluminum} compound with _a molecular structure of A method for producing a high molecular weight organoaluminum polymer suitable for molding fibers etc. is provided by carrying out the above reaction in the presence of 1.1 to 10 moles of an organic acid represented by (1 to 5 alkyl groups). This is what we provide. The organoaluminum compound used in the present invention has the general formula

In [Formula], if all of the residues X, Y, and Z are hydrogen, an alkyl group, or an alkoxyl group, even if they are completely different residues or the same residue, Two residues may be the same and the remaining residues may be different. In addition to hydrogen, alkyl groups include: methyl group, ethyl group, normal propyl group, isopropyl group, normal butyl group, and their isomers (for example, butyl group) There are various alkyl groups such as isobutyl group, secondary butyl group, and tertiary butyl group (the same applies hereinafter), normal pentyl group and its isomers, normal hexyl group and its isomers, etc. As a group: methoxyl group, ethoxyl group, normal propoxyl group,
Examples include various alkoxyl groups such as isopropoxyl group, normal butoxyl group and its isomers, normal pentoxyl group and its isomers, normal hexanoxyl group and its isomers. Further, in the present invention, the various organoaluminum compounds described above may be used alone or in a mixture of two or more types. If the amount of water used in the condensation polymerization reaction with the organoaluminum compound is in the range of 1.0 to 3.5 parts in molar ratio to 1 part of the organoaluminum compound, it is effective for producing a high molecular weight organoaluminum polymer. A range of 1.0 to 2.0 parts is preferred. The organic acid used in the present invention is represented by the above general formula, and specifically, methoxypropionic acid,
Examples include ethoxypropionic acid. The main saturated aliphatic monocarboxylic acids include various saturated aliphatic monocarboxylic acids such as acetic acid, propionic acid, butyric acid, isobutyric acid, pivalic acid, octanoic acid, lauric acid, and stearic acid.
Unsaturated aliphatic monocarboxylic acids include various unsaturated aliphatic monocarboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, and oleic acid.
Examples of alicyclic carboxylic acids include cyclohexanecarboxylic acid. Furthermore, the main substituents in the above-mentioned organic acids containing substituents in the main chain of the molecule are chlorine,
Examples include amino groups, hydroxyl groups, carboxyl groups, various alkoxyl groups, phenyl groups, and aryl groups. Further, in the present invention, the various organic acids described above may be used alone or in a mixture of two or more types. Organoaluminum compounds, water, and organic acids can be used without a solvent, but it is generally more convenient to handle them if they are diluted with an organic solvent, and they are also effective against condensation polymerization reactions. It is true. Organic solvents include organoaluminum compounds,
Any organic solvent that dissolves water and organic acids and does not react with these substances is effective, but in particular hydrocarbons such as benzene, toluene, xylene, tetralin, decalin, pentane, hexane, heptane, etc. Solvents: Ether solvents such as dioxane, diethyl ether, 1,2-dimethoxyethane, tetrahydrofuran, anisole, etc. Tertiary amine solvents such as pyridine, picoline, triethylamine: Polar solvents such as dimethyl sulfoxide, dimethylformamide, etc. I can list the types etc. In the condensation polymerization reaction between an organoaluminum compound and water, water can be added all at once, but since the reaction is quite rapid, it is preferable to add the water gradually. It is preferable to use Regarding the addition of the organic acid, it may be added all at once as in the case of water, but it is preferable to add it gradually. Also, regarding the order of addition of the organoaluminum compound, water, and organic acid, there is no problem if the organoaluminum compound is added later, but it is more convenient to determine the order of addition of water and organic acid to the organoaluminum compound. It is. As for the order of addition of the organic acid to water, the organic acid may be added during the condensation polymerization reaction between the organoaluminum compound and water, or after the condensation polymerization reaction.
Further, water may be added after adding an organic acid to an organoaluminum compound. Furthermore, an organic acid may be added to a polymer produced by a condensation polymerization reaction between an organoaluminum compound and water. The amount of the organic acid used in the present invention is in the range of 1.1 to 10 mol, preferably 1.5 to 3.5 mol, per 1 mol of the organoaluminum compound. The reaction temperature during the production of the organoaluminum polymer is not particularly limited as long as it is 200°C or less, but it is desirable to select it depending on the types of the organoaluminum compound, organic acid, and organic solvent used. In addition, industrially, it is natural to carry out the process between 0°C and around 60°C. The solution viscosity of the organoaluminum polymer obtained by the method of the present invention is 0.5 to 3.7 in terms of the relative viscosity indicating the molecular weight of the polymer (tetrachloroethane/phenol mixed solution, 30°C, concentration 0.5 g/dl). ), while the relative viscosity of the obtained polymer was approximately It was below 0.2. The present invention will be explained in more detail below with reference to Examples, but the present invention is not limited thereto. Example 1 6.66 g (58 mmol) of triethylaluminum was placed in a 200 ml three-necked flask fitted with a dropping funnel, a reflux condenser, and a three-way pot, and diluted with 24 ml of tetrahydrofuran. This solution was kept at -30℃ in an argon atmosphere, and while stirring vigorously with a magnetic stirrer, 1.04 g of distilled water was added.
10 ml of tetrahydrofuran solution containing (58 mmol) was gradually added dropwise over 1 hour. After the dropwise addition was completed, the solution temperature was raised to room temperature, and an additional 10.3 g (87 mmol) was added.
of 3-ethoxypropionic acid was added dropwise into the solution. A homogeneous, clear, viscous solution was obtained by standing overnight at room temperature. Then this solution
The mixture was poured into 500 ml of hexane and reprecipitated to obtain 10.8 g of a white powdery organoaluminum polymer.
The relative viscosity of an equal weight mixed solution of phenol and tetrachloroethane (concentration 0.5 g/dl, temperature 30°C) of this polymer was 0.81. Example 2 Using the same atmosphere and equipment as in Example 1, 7.35 g of diisobutylaluminum hydride was prepared.
(50 mmol) was diluted with 30 ml of dioxane, and a solution of 17.7 g (150 mmol) of 3-ethoxypropionic acid in dioxane (30 ml) was added dropwise to react at -78°C. Next, this system was gradually heated to 50° C., and then a solution of 1 g (56 mmol) of distilled water in dioxane (10 ml) was added while stirring well, and the mixture was allowed to react overnight.
Thereafter, the reaction solution was poured into a large amount of hexane and reprecipitated to obtain 12.8 g of an organoaluminum polymer. The relative viscosity of this polymer under the same conditions as in Example 1 was 0.52. Example 3 Using the same atmosphere and the same equipment as in Example 1, diethylaluminium 3-methylphenolate (bp,
130° C./0.1 mmHg) was dissolved in 20 ml of tetrahydrofuran, and a solution of 1.1 g (62 mmol) of distilled water in 10 ml of tetrahydrofuran was gradually added dropwise to react while stirring well at room temperature. After the dropwise addition was completed, stirring was continued for another 2 hours, and tetrahydrofuran was removed under reduced pressure to produce a white flake-like product.
6.2g was obtained. 1 g of this isolated product was taken, 10 ml of toluene and 2 ml of 3-methoxypropionic acid were added, and the mixture was stirred at room temperature. After standing for a day and night, the solution was poured into a large amount of hexane and reprecipitated to obtain 2.1 g of a white powdery organoaluminum polymer. The phenol of this polymer
Equal weight mixed solution of tetrachloroethane (concentration 0.4
The relative viscosity (g/dl, temperature 30°C) was 1.2.
The relative viscosity of the condensation polymerization reaction product of diethylaluminum 3-methylphenolate and water under the same conditions was 0.03 in the same solution.

Claims (1)

[Claims] 1. In the production of an organoaluminum polymer by a condensation polymerization reaction between an organoaluminum compound having a structure of the general formula [formula] type and water, a compound of the general formula
A high molecular weight organoaluminum characterized in that the above reaction is carried out in the presence of 1.1 to 10 moles of an organic acid represented by ROCH ₂ CH ₂ COOH (wherein R represents an alkyl group having 1 to 5 carbon atoms). Polymer manufacturing method. However, residues X, Y, and Z all represent hydrogen, an alkyl group, and an alkoxyl group;
Z may be completely different residues or the same residue, or any two of residues X, Y, and Z may be the same residue and the remaining residues may be different residues. There is no problem.