JPH0447692B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to a method for producing aromatic polyamideimide ether, and more specifically to a method for efficiently producing aromatic polyamideimide ether having excellent mechanical properties, heat resistance, processability, etc. BACKGROUND OF THE INVENTION It is well known that polytrimellitamideimides can be obtained by reacting trimellitic anhydride or its functional derivatives with aromatic diamines or their functional derivatives. In particular, polytrimellitamide imide ether, which uses 4,4'-diaminodiphenyl ether as the aromatic diamine component, has a good balance of heat resistance, processability, cost, etc. among heat-resistant polymers. It has been put into practical use for a variety of applications such as varnishes, films, and molding resins. However, this polytrimellitamide imide ether has a problem in its manufacturing method. This problem manifests itself, for example, when trying to obtain a polymer capable of forming a flexible film by direct polymerization of trimellitic anhydride and 4,4'-diaminodiphenyl ether. That is, since such polymerization is generally difficult to perform by melt polymerization, N-
A high-boiling polar solvent such as methylpyrrolidone is used as a plasticizer rather than a reaction solvent, and thermal polymerization is carried out at high concentrations. However, when 4,4'-diaminodiphenyl ether is used, the polymerization solution is removed during the polymerization. It becomes sticky and eventually becomes sticky and glue-like, making further polymerization difficult and making it impossible to obtain a polymer with a high degree of polymerization. Furthermore, once the polymerization solution becomes cloudy, even if a solvent is added to dilute it, it will not become a homogeneous solution. Therefore, in order to obtain a film, it is necessary to first dilute a polymerization solution of a low polymerization degree polymer to form a dope, apply it, and then perform post-polymerization and curing at a temperature of about 250°C. However, in this case, it cannot be said that the processability is sufficient, and there is a risk that a new problem may arise in that the polymer concentration is low and the coating becomes rough due to the solvent. OBJECT OF THE INVENTION The present inventor has solved this problem and has improved mechanical properties.
As a result of intensive studies to obtain an aromatic polyamideimide polymer with excellent heat resistance and processability, we found that when 3,4'-diaminodiphenyl ether is used as the aromatic diamine and the reaction is carried out in the presence of a specific compound, The inventors have discovered that the above polymer can be obtained efficiently and have arrived at the present invention. Therefore, the purpose of the present invention is to improve mechanical properties, heat resistance,
The object of the present invention is to provide a method for efficiently producing aromatic polyamideimide ether having excellent processability. Structure/Effects of the Invention According to the present invention, an object of the present invention is to provide (A) an aromatic tricarboxylic acid and/or its acid anhydride, (B) 3,
4'-diaminodiphenyl ether and/or its lower fatty acid amide, (C) a diphenyl compound represented by the following formula (1), Ar ¹ -X-Ar ¹ ... (1) (where X is -O -, -SO ₂ -, -CO- or an alkylene group, and Ar ¹ is a phenyl group that may have a substituent). This is achieved by the manufacturing method. The aromatic tricarboxylic acid used as component A in the present invention is a compound represented by the following general formula. (However, in the formula, Ar is a trivalent aromatic group in which two bond positions are adjacent to each other.) As Ar (trivalent aromatic group) in the above general formula (),

【formula】

【formula】

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【formula】

【formula】

【formula】

[Formula] etc. can be exemplified. child Among these, especially

[Formula] is preferred. As a specific compound, trimellitic acid is particularly preferred. Furthermore, the acid anhydride of aromatic tricarboxylic acid used as component A in the present invention has the above general formula ()
It is an acid anhydride of a compound represented by, and trimellitic anhydride is particularly preferred. In the present invention, a portion of the aromatic tricarboxylic acid and/or its acid anhydride may be replaced with dicarboxylic acid, tetracarboxylic acid, tetracarboxylic acid anhydride, or the like. Specific examples of such compounds include terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, succinic acid, adipic acid, sebacic acid, decanedicarboxylic acid, cyclohexanedicarboxylic acid, pyromellitic acid, pyromellitic anhydride, diphenyl Examples include tetracarboxylic acid, diphenyltetracarboxylic anhydride, benzophenonetetracarboxylic acid, benzophenonetetracarboxylic anhydride, and the like. It is preferable to use these in an amount of 40 mol % or less, more 30 mol % or less, particularly 20 mol % or less, based on the total acid components. Further, the diamine used as component B in the present invention is 3,4'-diaminodiphenyl ether or its lower fatty acid amide, and a portion thereof may be substituted with other types of diamine or its lower fatty acid amide. Examples of lower fatty acids that form this amide include acetic acid, propionic acid, and butyric acid. Particularly preferred is acetic acid. Specific examples of other diamines include p-phenylenediamine,
m-phenylenediamine, tolylenediamine,
4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl,
3,3'-dimethyl-4,4'-diaminodiphenyl, 4,4'-diaminobenzophenone, 4,4'-
Examples include diaminodiphenylsulfone, ethylenediamine, tetramethylenediamine, hexamethylenediamine, decamethylenediamine, and the like.
These are preferably used in an amount of 40 mol % or less, more 30 mol % or less, particularly 20 mol % or less based on the total diamine components. The proportion of diamine used is usually substantially equivalent to the amount of component A. In the present invention, a small proportion of an aminocarboxylic acid such as p-aminobenzoic acid, m-aminobenzoic acid, etc. may be used in combination with the A component and the B component for copolymerization. The proportion of this aminocarboxylic acid is preferably 30% or less, particularly 20% or less, based on all repeating units. In the present invention, component A and component B, and optionally an aminocarboxylic acid component, are used to form (C)
Heat condensation is carried out in the presence of a low-molecular compound with a boiling point of 30°C or higher, which is compatible with the polymer to be produced and is substantially non-reactive with the polymer, but this low-molecular compound (C) is Molecular weight less than 1000, even
Preferably, it is 800 or less. In the present invention, a diphenyl compound represented by the above formula (1) is used as the low molecular weight compound (C). Such compounds include, for example, diphenylsulfone, 4,4'-diphenoxydiphenylsulfone, 4,4'-bis(4- or 3- or 2-chlorophenoxy)diphenylsulfone, 4,4'-
Bis(4- or 3- or 2-phenylphenoxy) diphenylsulfone, 4,4'-bis(4-
or 3- or 2-tbutylphenoxy) diphenylsulfone, 4,4'-bis(4- or 3-
or 2-octylphenoxy) diphenyl sulfone, 4,4'-bis(α or β-naphthyloxy) diphenyl sulfone, and the like. Among these, diphenyl sulfone is particularly preferred. In the present invention, the low molecular weight compound as component C is preferably 5 to 200% by weight based on the produced polymer.
More preferably 10 to 100% by weight, particularly preferably
It is used in a proportion of 20 to 70% by weight. The reaction between component A and component B, optionally using an aminocarboxylic acid component, is usually carried out over 200 to
350℃, preferably 250-320℃, particularly preferably
The reaction is carried out at a temperature of 260 to 310°C while water produced by the reaction is distilled out of the system. At this time, the reaction atmosphere may be normal pressure, increased pressure, or reduced pressure. In the case of a normal pressure reaction, it is preferable to carry out the reaction under an atmosphere of an inert gas such as nitrogen gas, argon gas, etc. Further, it is preferable to use a catalyst, a stabilizer, etc. in the reaction. Examples of this catalyst include various phosphorus compounds, boron compounds,
Examples include heteropolyacids. Specific examples include trimethyl phosphite, triethyl phosphite, triphenyl phosphite, phosphoric acid, triphenyl phosphite, and boric acid. Examples of the stabilizer include hindered phenol oxidation stabilizers. In this way, an aromatic polyamide ether having a desired degree of polymerization, particularly a high degree of polymerization, can be obtained in a mixed state with a low molecular weight compound. The aromatic polyamideimide ether can be subjected to molding as a mixture with a low-molecular compound, or can be subjected to molding after being separated from the low-molecular compound. Separation of low molecular weight compounds is preferably carried out by extraction treatment with an organic solvent that dissolves only the low molecular weight compounds. Preferred examples of the organic solvent include aromatic hydrocarbons, halogenated aliphatic hydrocarbons, aliphatic ketones, aliphatic ethers, cyclic ethers, and more specifically toluene, xylene, methylene chloride, chloroform,
Preferred examples include acetone, methyl ethyl ketone, methyl acetate, ethyl acetate, and dioxane. Since the compatibility of the low molecular weight compound (C) with aromatic polyamideimide ether is significantly greater than that with conventional reaction solvents, it is possible to increase the concentration of aromatic polyamideimide ether in the reaction product in the present invention. can. In this case, the reaction product can be directly subjected to molding without adjusting the concentration of the polymer. In the aromatic polyamideimide ether obtained by the present invention, 60 mol% or more of the total repeating units are of the following formula: However, the expressions in parentheses may be independently reversed. The repeating unit represented by, especially the following formula However, the expressions in parentheses may be independently reversed. A polymer consisting of repeating units represented by is preferred. The aromatic polyamide-imide ether obtained in the present invention can be used in a wide range of applications such as varnishes, adhesives, films, fibers, matrix resins for fiber-reinforced composites, and molding resins for compression molding, extrusion molding, injection molding, etc. I can do it. For example, for varnishes, it is generally in the form of a solution containing N-methylpyrrolidone or cresol as the main solvent, and can be used for enamel varnishes for electric wires, aluminum fixtures, etc. Furthermore, it can be powdered and used for metal surface coatings by powder baking. Films and fibers can be formed from a solution of the aromatic polyamideimide ether by wet or dry molding. Both can be used for electrical insulation, protective clothing, etc. by taking advantage of their good heat resistance and flame retardancy. As the adhesive, it is possible to use a dry film adhesive formed into a film, or a solution adhesive in which a solution is applied to an adherend and then heat-sealed after drying. Preferred examples of the adherend include metals, particularly iron, aluminum, stainless steel, copper, and the like. The matrix resin for fiber-reinforced composite materials can be applied to the surface of reinforcing fibers in the form of a solution or powder fluidized bed, formed into a strand, unidirectional prepreg, etc., and then molded in an autoclave, press molded, etc.
A molded article can be obtained by means such as filament widening. For the molding resin, we create a molding resin compound with various additives.
Using it, a molded article can be obtained by compression molding, extrusion molding, injection molding, etc. The molded products described above have well-balanced performance in heat resistance, mechanical properties, and chemical resistance, and are used as functional parts for various transportation equipment such as aerospace, automobiles, and ships, It can be widely used in advanced technology fields as a component for electronics, automation equipment, sporting goods, energy equipment, etc. In actual use, various additives, other polymers, etc. can be blended and used. Examples The present invention will be explained in detail with reference to Examples below. The examples are illustrative and not limiting. Example 1 3,4'diaminodiphenyl ether was added to a reactor equipped with a stirrer, a nitrogen gas inlet, and a by-product distillation outlet.
20.0g, trimellitic anhydride 19.2g, triphenyl phosphite 0.2g and diphenyl sulfone
After charging 15.3 g and thoroughly purging the inside of the reactor with nitrogen, the reaction was carried out for 2 hours while water produced at 280° C. was distilled out of the system in a nitrogen gas stream. The resulting reaction product mixture was transparent. Next, this mixture was crushed into 10 to 20 meshes and immersed in acetone to extract diphenyl sulfone under heating. The polymerization degree of the obtained polymer was NMP (N-
ηinh measured at 0.5 g/d in methylpyrrolidone) at 30°C was 0.64. Comparative Example 1 The same procedure as in Example 1 was carried out except that 4,4'-diaminodiphenyl ether was used instead of 3,4'-diaminodiphenyl ether. About 30 minutes after the start of the reaction, the reaction system solidified. Uniform stirring became impossible. Examples 2 to 5 The same procedure as in Example 1 was carried out except that the low molecular weight compound shown in Table 1 was used instead of 15.3 g of diphenylsulfone, and the reaction temperature and time were changed as shown in Table 1. All reaction product mixtures obtained were transparent. Next, the mixture was extracted in the same manner as in Example 1, and the ηinh of the obtained polymer was determined. The results are shown in Table 1.

[Table] Comparative Example 20.0 g of 3,4'-diaminodiphenyl ether, 19.2 g of trimellitic anhydride, 0.18 g of triphenyl phosphite, and N- After charging 33.4 g of methylpyrrolidone (NMP) and thoroughly purging the inside of the reactor with nitrogen, the reaction was carried out by heating in a nitrogen gas stream. N-methylpyrrolidone containing by-product water was distilled off from the reactor, and the viscosity of the solution gradually increased, as well as the internal temperature of the reactor. Approximately 28.3
The temperature inside the system was 262°C at the time when g of NMP (water content) was distilled off. A portion of this solution was taken out and precipitated with water in a mixer in a conventional manner to obtain a polymer powder. The degree of polymerization of this polymer was measured by NMP at a concentration of 0.5 g/d at 30°C, and ηinh was 0.26.

Claims (1)

[Scope of Claims] 1 (A) aromatic tricarboxylic acid and/or its acid anhydride and (B) 3,4'-diaminodiphenyl ether and/or its lower fatty acid amide, (C) the following formula ( 1)
A diphenyl compound represented by Ar ¹ -X-Ar ¹ (where X is -O-, -SO ₂ -, -CO- or an alkylene group, and Ar ¹ is a phenyl group that may have a substituent) A method for producing an aromatic polyamideimide ether, which comprises carrying out thermal condensation in the presence of