JPH0219847B2 - - 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. As an excellent method for producing alumina fibers, a method based on firing precursor fibers made of organoaluminum polymers has been attracting attention. lacked a good manufacturing method,
That is, it is already known that an organoaluminum polymer can be obtained by the reaction of an organoaluminum compound and water, but depending on the known method, the general formula

It has been difficult to obtain a high molecular weight polymer suitable for molding into fibers, etc. from an organoaluminum compound having a molecular structure of the following formula and water. For this reason, the present inventors have conducted various studies on methods for obtaining high-molecular-weight organoaluminum polymers suitable for molding fibers, etc., and have found that in the reaction of organoaluminum compounds and water, the molar ratio If an organic acid is added in an amount of 0.2 to 10 times, and the amount of water added is in the range of 1.0 to 3.5 times in molar ratio, a high molecular weight organoaluminum compound suitable for molding into fibers etc. can be easily and efficiently obtained. I discovered that it can be done. The present invention is based on the general formula

[Formula] When producing an organoaluminum polymer by reacting an organoaluminum compound having a molecular structure of type with water,
Water in molar ratio 1.0 to 3.5 times, organic acid in molar ratio
The present invention provides a method for producing a high molecular weight organoaluminum polymer suitable for forming fibers etc. by adding 0.2 to 10 times the amount. The organoaluminum compound used in this method has the general formula

In [Formula], both X and Y are hydrogen, an alkyl group, or an alkoxyl group, and as long as R is an organic residue, it is valid whether X and Y are the same residue or different residues. It is. If I were to list the main things about X and Y,
In addition to hydrogen, alkyl groups include: methyl group, ethyl group, normal prokyl group, isoprokyl group, normal butyl group, and their isomers (for example, for butyl groups, include isobutyl group, secondary butyl group,
Indicates a tertiary butyl group. There are various alkyl groups such as normal pentyl group and its isomers, normal hexyl group and its isomers, and examples of alkoxyl groups include: methoxyl group, ethoxyl group, normal propoxyl group, and isopropoxyl group. , normal butoxyl group and its isomers, normal pentoxyl group and its isomers, normal hexanoxyl group and its isomers. for R saturated and unsaturated aliphatic substituents;
Various organic residues such as alicyclic substituents and aromatic substituents are effective. The main organic residues include saturated aliphatic substituents: methyl group, ethyl group,
There are various alkyl groups such as normal propyl group, isoprokyl group, normal butyl group and its isomers, normal pentyl group and its isomers, normal nonyl group and its isomers, and alicyclic substituents include There are cyclohexyl groups, etc. In addition, unsaturated aliphatic substituents include: vinyl group,
There are various alkenyl groups such as allyl group and crotyl group, as well as mono-, di- and tri-unsaturated hydrocarbon groups such as butadienyl group and octatrienyl group, as well as ethynyl group, procypinyl group, etc. Examples include alkynyl groups. Examples of the aromatic group include various aryl groups such as phenyl group, tolyl group, anisyl group, and naphthyl group. Furthermore, regarding saturated aliphatic substituents, unsaturated aliphatic substituents, alicyclic substituents, aromatic substituents, etc., chlorine, amino groups, hydroxyl groups, carboxyl groups, various alkoxyl groups, aryl groups, etc. It is also effective even if it contains one or more of various substituents. In addition to the various organoaluminum compounds mentioned above, the organoaluminum compound may be a mixture of two or more organoaluminum compounds containing organic residues in which R is different. The amount of water used for the reaction with the organoaluminum compound is determined by the molar ratio to the organoaluminum compound.
If the amount is in the range of 1.0 to 3.5 times, it is effective for producing high molecular weight organoaluminum polymers, but 1.0
A range of 3.5 to 3.5 times the amount is preferred. Most organic acids are effective, but
The main ones include saturated and unsaturated aliphatic monocarboxylic acids excluding formic acid, alicyclic carboxylic acids, aromatic monocarboxylic acids, dicarboxylic acids, hydroxycarboxylic acids, and those containing substituents in the main chain of the molecule. These include the various organic acids mentioned above. 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. The main aromatic monocarboxylic acids are:
These include succinic acid, glutaric acid, phthalic acids, cyclohexanedicarboxylic acids, etc., and the main hydroxycarboxylic acids include glycolic acid, lactic acid, mandonic acid, etc. 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. In addition, the type of organic acid added in the reaction between the organoaluminum compound and water is the same as the organic acid (RCOOH) corresponding to the above-mentioned organic residue (R) in the organoaluminum compound used, or this organic acid. It is preferable to use an organic acid that is more acidic than the organic acid. For example, when the organic residue of the organoaluminum compound used in the reaction is an undecyl group, the corresponding organic acid is lauric acid. Typical organic acids with high oxidation levels include hexanoic acid, butyric acid, valeric acid, acetic acid, methacrylic acid, and acrylic acid (representative organic acids are listed from among saturated and unsaturated aliphatic monocarboxylic acids). The organic acids are not limited to these organic acids. Organoaluminum compounds, water, and organic acids can be used without a solvent, but it is generally easier to handle and more effective for reactions if they are diluted with an organic solvent. be. In particular, when using a solid acid as the organic acid, it is better to use it after diluting it with an organic solvent. Organic solvents include organoaluminum compounds,
Any organic solvent that dissolves water and organic acids and does not react with them 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, and anisole, tertiary amine solvents such as pyridine, picoline, and triethylamine, polar solvents such as dimethyl sulfoxide, dimethylformamide, etc. I can give you. In the 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, and the water added dropwise should also be used diluted with a solvent. It is preferable. 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. The reaction temperature for producing organoaluminum polymer is not particularly limited as long as it is 200°C or less, but
Organoaluminum compounds, organic acids,
It is desirable to select according to the type of organic solvent. Further, industrially, it is economical to carry out the process at a temperature 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 5.5 in terms of relative viscosity indicating the molecular weight of the polymer (mixed solution of equal amounts of tetrachloroethane and phenol, 30°C, concentration 0.5 g/dl). ), whereas, according to the results obtained by the present presenters using a known method using the same organoaluminum compound and adding 0.1 to 1.2 times the amount of water, 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 15 g of diisobutyl aluminum 3-ethoxypropionate (58 m
mol) and 30 ml of tetrahydrofuran were placed in a three-necked flask equipped with a dropping funnel, reflux condenser, and three-way pot, and stirred with a magnetic stirrer in a nitrogen atmosphere at room temperature.
Tetrahydrofuran 10 containing 1.04g (58mmol)
ml solution and 3.44 g of ethoxypropionic acid (29 m
mol) was gradually added dropwise to react. A homogeneous, clear, viscous solution was obtained by standing overnight at room temperature. This solution exhibited good spinnability at room temperature, which is indicative of good fiber forming. Then add this solution to 500
ml of hexane and was reprecipitated to obtain 11.6 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 1.01. Example 2 16.5 g of diethylaluminum laurylate obtained by the reaction of triethylaluminum and lauric acid using the same atmosphere and the same equipment as in Example 1.
(58 mmol), 1.26 g of water in 30 ml of tetrahydrofuran
(70 mmol) and lauric acid 2.4 g (12 mmol)
was added and reacted at 60°C. After several hours, the system became a homogeneous, viscous solution. Then, the solvent tetrahydrofuran was gradually removed under reduced pressure, and the residue was washed with hexane and dried. As a result, 14 g of a white resinous organic aluminum polymer was obtained. A solution of this polymer in tetrahydrofuran (concentration:
The relative viscosity (0.5g/dl, temperature 30°C) was 2.41. Example 3 In the reaction system of Example 2, β-methoxypropionic acid (6.03%) was used instead of lauric acid as the organic acid added.
g (58 mmol) and left at 0°C overnight.
A uniform viscous solution was obtained as in Example 2, but
This was poured into a large amount of hexane to obtain 13.5 g of a white powdery organoaluminum polymer. A mixed solution of this polymer in equal weight of phenol and tetrachloroethane (concentration: 0.5 g/dl, temperature 30°C)
The relative viscosity of was 1.6. Example 4 Using the same atmosphere and the same equipment as in Example 1, 0.45 g (25 mmol) of water and 9.0 g of propionic acid were added to a solution of 5.8 g (25 mmol) of isopropoquine secondary butoxyaluminum propionate and 50 ml of benzene.
g (125 mmol) was added at the same time and reacted at room temperature. After standing overnight, the thread was poured into hexane and reprecipitated to obtain 3.81 g of polymer. The phenol
Equal weight mixed solution of tetrachloroethane (concentration 0.5
The relative viscosity (g/dl, temperature 30°C) was 0.77. Example 5 Diisopropoxyaluminum secondary butoxide 5.45g (25mmol) and benzoic acid 3.05g (25mmol)
20 ml of a decalin solution containing a mixed product of diisopropoxyaluminum benzoate and isopropoxy secondary butoxyaluminum benzoate obtained by reaction with 0.68 g of water in the same atmosphere and apparatus as in Example 1. (38 mmol)
3.05 g (25 mmol) of benzoic acid was added thereto, the mixture was reacted at 50°C, and the mixture was left at the same temperature overnight. Then Example 4
In the same manner as above, 5.3 g of an organoaluminum polymer was obtained. Its dimethylformamide solution (concentration 0.5
The relative viscosity (g/dl, temperature 30°C) was 3.1.

Claims (1)

[Claims] 1. When producing an organoaluminum polymer by reacting an organoaluminum compound having a molecular structure of general formula [formula] type with water, the molar ratio of water to the organoaluminum compound is 1.0 to 1.
A method for producing a high molecular weight organoaluminum polymer, characterized by adding 3.5 times the amount and 0.2 to 10 times the molar amount of an organic acid. However, both X and Y are hydrogen, alkyl groups,
It represents an alkoxyl group, and X and Y may be the same residue or different residues. Further, R represents one or more types of organic residues.