JPS61285224A - Polyamide imide resin composition - Google Patents

Abstract

PURPOSE:The titled novel resin composition, obtained by reacting a poly carboxylic acid with a polyamine in the presence of a polyamide resin and further reacting the resultant product with a polyhydric alcohol and having improved heat resistance, solubility and mechanical characteristics and high molecular weight in a high concentration. CONSTITUTION:A composition obtained by reacting (A) a polycarboxylic acid (derivative), preferably trimellitic acid anhydride with (B) a polyamine, preferably an aromatic diamine, e.g. p-phenylenediamine, at 1:1 equivalent ratio in the presence of (A) a polyamide resin, preferably in a phenolic solvent, normally at 150-250 deg.C for 2-20hr and further reacting the resultant reaction product with (D) a polyhydric alcohol, preferably diphenylsilanediol, preferably at 180-250 deg.C normally for 1 - some ten hours. Preferably, the components (D) is used in an amount of 5-40wt% based on the resin content in the composition.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to a novel polyamide-imide resin composition useful as an electrically insulating varnish or the like.

(Technical background of the invention and its problems) In recent years, with the need for resource and energy conservation and the miniaturization and weight reduction of peripheral devices, the high performance and miniaturization of electrical equipment itself has been progressing. Polyamide-imide resins, which have well-balanced mechanical properties, electrical properties, and economic efficiency, are becoming increasingly important in the field of electrical insulation materials, including edge varnishes.

Traditionally, trimellitic anhydride and aromatic diamine,
For example, it is known that a polyamide amide resin composition with a high p polymerization degree can be obtained by reacting in an aprotic polar solvent such as N-methyl-2-pyrrolidone or dimethylacetamide.

However, the polar solvent used in this method is highly hygroscopic;
Pseudo-gelling phenomena, clouding phenomena, etc. tend to occur when varnishes are used, making it difficult to store and manage the varnishes. Furthermore, the use of a special aprotic releasing solvent increased the price of the varnish and made it less useful industrially.For this reason, phenolic solvents are very commonly used as solvents for electrical insulation varnishes. There are not many proposals for 9-polyamide-imide resin using solvents (for example,
No. 23999, Special Publication No. 56-17374, Special Publication No. 17374
-22330, Special Publication No. 56-34210).

However, even if an attempt is made to obtain a polyamideimide resin by simply reacting trimellitic anhydride and an aromatic diamine such as 4,4'-diaminodiphenylmethane in a phenolic solvent, a cloudy precipitate or a homogeneous solution is obtained. Even if the reaction is carried out at a high temperature above the boiling point of the phenolic solvent, aryl esters and the like are formed at the ends, making it impossible to obtain a high molecular weight polymer that can be used as a practical insulating varnish.

When using aliphatic dicarboxylic acids, lactams, etc., the solubility in phenolic solvents improves, but on the other hand, the heat resistance, especially the heat softening temperature at 9 o'clock when used as an insulated wire, is lower than that of aromatic polyamide-imide resins. It has the disadvantage of being inferior.

(Purpose of the Invention) The present inventor has conducted various studies on the reaction between polycarboxylic acids and polyamines, and has found that a polymer with excellent heat resistance and extremely heavy polymerization can be obtained in the reaction in the coexistence of a polyamide resin, and that a polyamide resin coexisting therein can be obtained. The aromatic polyamide-imide resin is integrated with fc, which has excellent heat resistance and solubility.
It was discovered that a polyamide-imide resin with a fft standard was obtained, and that a polyamide-imide ester resin with a high # degree could be obtained by reacting this resin composition with a polyhydric alcohol.
The present invention was made based on this knowledge, and it is an object of the present invention to provide a polyamide-imide resin composition that does not have the above-mentioned conventional drawbacks.

(Summary of the Invention) That is, the present invention provides a polyamide-imide resin characterized by reacting a polyhydric alcohol with a resin composition obtained by reacting a polycarboxylic acid or a derivative thereof with a polyamine in the coexistence of a polyamide resin. It is intended to provide a composition.

The polycarboxylic acids used in the present invention include dibasic acids or their derivatives, tribasic acid anhydrides or their derivatives, and tetrabasic acid anhydrides or their derivatives. The compound or its derivative can be used alone or by partially replacing it with other polycarboxylic acids, and the tetrabasic acid anhydride or its derivative can be used by mixing it with other polycarboxylic acids.

Examples of dibasic acids or derivatives thereof used here include oxalic acid and dibasic acids and dibasic acid esters represented by formula (1).

R'OOCR2C00RT (1) Among these dibasic acids or derivatives thereof, aromatic dibasic acids or derivatives thereof are particularly preferable because of their heat resistance.

As tribasic acid anhydrides or derivatives thereof, citric acid, aromatic tricarboxylic acids, aromatic tricarboxylic acid esters, aromatic tricarboxylic acid amethysts, and the like represented by formulas (1') and (If'') are used. .

R2(COORT)s −・==−(1 O RT OOCR1<>O−・・・・・・(If”
) O From the viewpoint, trimellitic acid anhydride is preferred.

Tetrabasic acid anhydrides or derivatives thereof are, for example, pyrometh) acid 1
hydrate, 3.3',4,4'-ben/phenonetetracarboxylic anhydride, 3.3',4.4'-diphenyltetracarboxylic anhydride, naphthalenetetracarboxylic anhydride, butanetetracarboxylic acid There are acid anhydrides such as anhydrides, and derivatives such as acids and esters.

The polyamines used in the present invention include aliphatic, alicyclic,
Aromatic diamines are mainly used.

Suitable diamines include ethylene/diamine/, trimethylene diamine, tetramethylene diamine, pentamethylene diamine, hexamethylene diamine, heptamethylene diamine, octamethylene diamine, nonamethylene diamine, decamethylene diamine, trimethylhexamethylene diamine, and morpholine. Diamine, cyclohexane-1
, 4-diamine, 3,9-bis(3-aminopropyl)
-2,4,8,10-tetraoxaspiro [5] Undecane and other aliphatic and alicyclic diamines, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 4,4'- Diaminodiphenylpropane, 4,4'-diaminodiphenylsulfone, 3,3'-
Diaminodiphenylsulfone, 4,4'-diaminodiphenylsulfite, 3゜3'-dimethyl-4,4'-
Diaminodiphenylmethane, 3,3'-dichloro-4,
4'-diaminodiphenylmethane, 3,3'-dimethoxy-4,4'-diaminodiphenyl, 3,3'-dimethyl-4,4'-diaminodiphenyl, 4,4'-diaminodiphenyl, m-phenylenediamine, p - Aromatic diamines such as phenylene diamine, 2,4-diaminotoluene, 2,6-diaminotoluene, m-kylenediamine, and p-xylylene diamine can be used alone or in combination. A part of the diamine can also be replaced with a trivalent or higher polyamine such as 3,3',4'-IJ aminodiphenylmethane, 3.3',4,4'-tetraaminodiphenylmethane, etc., for the purpose of increasing the crosslinking component. .

Among the polyamines, aromatic diamines are particularly preferred from the viewpoint of heat resistance and mechanical properties of the insulating film.

The polyamide resin coexisting during the reaction of polycarboxylic acid or its derivative with polyamine has a nine-linear shape in which amide groups are repeated as the main part of the polymer chain and alkylene groups are bonded together. Synthetic polymers such as ordinary molecular-jtlo, nylon having a molecular weight of 000 or more, or aromatic polyamide resin can be used.

Examples of nylon include nylon 6, nylon 66,
There are copolymerized nylons obtained by mixing and polymerizing nylon 61O, nylon 11, chilon 12, and two or more types of homonylon monomers, and these can be used alone or in combination.

Aromatic polyamide resins include aromatic rings as acid or amine components, and are obtained, for example, by the reaction of aromatic dicarboxylic acids and aliphatic diamines. Those that dissolve in system solvents at high temperatures can also be conveniently used. The reaction between a polycarboxylic acid or a derivative thereof and a polyamine in the coexistence of a polyamide resin is carried out in the presence of an organic solvent.
The reaction is carried out at a temperature of 0° C. for 2 to 20 hours.

Suitable organic solvents for the present invention include phenol, 0-cresol, m-cresol, p-cresol, various xylenolic acids, various chlorphenols, nitrobenzene, N-methyl-2-pyrrolidone, dimethylformamide, Examples of solvents that can be used in combination with these include dimethylacetamide, hexamethylphosphoramide, and dimethyl sulfoxide.
, Cresol 1500, Nippon Oil Nippon Oil Hysol xo
(O, etc.), ethylene glycol monomethyl ether acetate, etc.

Particularly preferred reaction solvents are phenolic solvents such as phenol, cresol, and xylenol from the viewpoints of solubility for the starting materials, stability of the resulting resin solution, film-forming properties, economic efficiency, etc. When used as an electrically insulating varnish. A suitable solvent is a mixture of the phenolic solvent and a high boiling point aromatic hydrocarbon solvent.

The blending ratio of carboxylic acid or its derivative and polyamine is preferably approximately 1:1 in terms of equivalent ratio, where 2 equivalents of polycarboxylic acid or derivative thereof and 91 equivalents per amino group of polyamine. But either - 10,000 equivalent%
The following excesses are acceptable.

Although the function of the polyamide resin in the synthesis reaction of the present invention is not clear, it significantly accelerates the reaction between polycarboxylic acid or its derivative and polyamine, the resulting resin exhibits excellent solubility, and infrared rays. From the results of molecular weight distribution measurements using charts, thermogravimetric analysis, and gel permeation chromatography, it is assumed that the aromatic polyamide-imide resin produced and the polyamide resin used during synthesis react with each other and become integrated. Does polyamide resin have a matrix effect in the reaction between polycarboxylic acid or its derivatives and polyamine? At the same time, it is thought that a polymerization reaction is occurring centering on the amide groups of the polyamide resin.

Therefore, the proportion of the polyamide resin used can be varied depending on the amount sufficient to produce the matrix effect, the intended use of the resulting resin, and the required properties. For example, when used as an electrical insulating varnish, 3 to 3
40% by weight is preferred. If it is less than 3% by weight, a sufficient matrix effect will not be exhibited, and if it exceeds 40% by weight, the heat resistance of the enamelled wire obtained from the insulating varnish will decrease.

On the other hand, when used as a film or molded product, it is possible to use polyamide resin in an amount of 40% by weight or more depending on the required properties.

The polycarboxylic acid or its derivative, the polyamine, and the polyamide resin may be added at the same time at the start of the reaction, or one may be dissolved in a solvent and the other may be added at once, and then the other may be added in several batches. There are no restrictions on the method. However, it is particularly preferable to add the polyamide resin from the start of the reaction in order to obtain a high molecular weight polyamide-imide resin. - When used as an electrical insulating varnish, the reaction proceeds even during the baking process to form an enamel film, so the polyamide resin can be added relatively late in the reaction in the varnish synthesis stage.

Although the above reaction proceeds satisfactorily in the absence of a catalyst, the reaction of the present invention can be accelerated with a catalyst commonly used for reactions of polyamines.

Examples of suitable catalysts include - lead oxide, boric acid, metal salts of naphthenic acids such as lead naphthenate and zinc, phosphoric acid, polyphosphoric acid, triethylamine, etc. The preferred use is based on the solid content at the time of charging. The amount is 0.01 to 5% by weight.

The reaction is controlled within an appropriate range by observing the degree of bubbling of generated carbon dioxide and wetting of distilled water, as well as the viscosity of the resin solution.

The polyhydric alcohols used in the present invention include ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol, 1,3-butanediol, 1,4-butanediol, 1,3- Propanediol, neopentyl glycol, 1,6-hexane glycol, trimethylolpropane, trimethylolethane glycerin, pentaerythritol, 1,5-bentanediol, cyclohexane-1,4-diol, sorbitol, hexitol, erythritol, tris (2-
Hydroxyethyl) isocyanurate, etc.

In order to further improve the adhesion and flexibility when binding the insulated wire by baking the resin composition of the present invention onto a conductor, a polyhydric alcohol having a valence of 3 or more may be used as the polyhydric alcohol. is preferable, especially glycerin, tris (
2- and droxyethyl) isocyanurate is preferred.

Further, diphenylsilane diol is suitable in order to further improve the burnout property. When reacting the polyhydric alcohol with the polyamide-imide resin composition,
The polyhydric alcohol may be directly added to the phenolic solution of the polyamide-imide resin composition to react, or the polyhydric alcohol may be reacted with the polyamide-imide resin once taken out in a solvent-free or other organic solvent.

However, in order to improve the efficiency of the reaction and to use the final resin solution, it is recommended to mix polyhydric alcohol in the final stage of the reaction of the polyamide-imide resin solution that has been submerged in a phenolic solvent and continue the reaction. Most preferred.

Since distilled water is generated when a polyhydric alcohol is blended into the polyamide-imide resin composition, the reaction temperature is preferably in the range of 180° C. to 250° C. at which distilled water can be completely distilled off.

The reaction time for this reaction varies depending on the degree of pressure reduction in the reaction system, but is usually in the range of 1 to 10-odd hours until no distilled water is observed. It is possible to use normal pressure, but in order to facilitate the generation of distilled water, it is also possible to reduce the pressure to the extent that the phenolic solvent is not distilled off.

Although this reaction can be carried out without a catalyst, it is also possible to use a catalyst commonly used in reactions using polyhydric alcohols.

Examples of such catalysts include - lead oxide, lead naphthenate,
Examples include metal salts of naphthenic acids such as zinc, organic titanium compounds such as tetrabutyl titanate, tetrapropyl titanate, and triethanolamine titanate.

The blending ratio of polyhydric alcohol is particularly important; if it is less than the recommended weight %, which is set in the range of 5 to 40% by weight based on the resin content of the resin composition, the resin content will not increase sufficiently, and %, it is not preferable because the flexibility and heat resistance of the insulated wire, especially the heat softening temperature, decreases.

The resin solution of the polyamide-imide resin composition of the present invention is
As it is, organic titanium compounds such as tetrabutyl titanate and tetrapropyl titanate, metal salts of naphthenic acid such as zinc naphthenate, Millionate MS-50 (protsquison anate manufactured by Nippon Polyurethane Co., Ltd.), Desmodur CT Stable (backed by Bayer Co., Ltd.) It can also be used as a fine NA paint by adding a curing agent such as block incyanate.

(Example of the invention) The present invention will be explained in detail with reference to Examples below.

Example 1 fC-3 equipped with a thermometer, stirrer, cooling pipe, nitrogen introduction pipe, etc.
Trimellitic anhydride 192.1 in 14 Tulo flask
? (1.0 mol) 4,4'-diaminodiphenylmethane 198f (1.0 mol), nylon 6 (Amilan CM1007 manufactured by Toshi Co., Ltd.) 40 t, m-cresylic acid (JIS K2451, equivalent to metacresylic acid No. 1) 4009 Hiroshi Shikomi, 2 in a nitrogen stream for about 1 hour.
The temperature was raised to 00°C. A lot of foaming due to dehydration was observed at 70 to 160°C. The reaction temperature was set to 205°C and the reaction was carried out at normal pressure. The contents, which were transparent immediately after the start of the reaction at 205° C., temporarily became opaque, but after about 2 hours became a reddish-brown, transparent, and uniform bath liquid. After 8 hours at 205°C, when the contents had become a viscous solution that was difficult to stir, tris (2- and 40
Add 0f at 200℃ and continue the reaction. When tris(2-hydroxyethyl)isocyanurate is added, a dehydration reaction is observed, and water is distilled out along with a small amount of m-waresol.

After 1 hour, 400 r71 Q of m-cresol, which had become difficult to stir due to the high viscosity of the contents, was added to stop the reaction.

This resin solution has a non-volatile content (200℃ x 1.5 hours937
Weight%, viscosity (30℃) It has a viscosity of 30 voids. The obtained resin solution is 10 mm long, 3 mm wide, and 0.1 t thick.
The coating was applied uniformly to a copper plate of Im to a film thickness of about 15 μm, heated at 230°C for 30 minutes, and then the copper plate was heated to a temperature of 180°C.
A flexible coating film was obtained that did not cause cracks even when bent.

According to the usual method, furnace length 7m, furnace temperature 430-380-280
(Top → Bottom), 1. Using the obtained n* resin solution under the condition of linear speed of 10 m/min. The insulated wire was coated and baked 7 times on the copper wire inside the wire to form an insulated wire with a coating of about 38 μm. JIS
The characteristics measured in accordance with C3003 are as shown in Table 1.

Table 1 Comparative Example Using the same equipment as in Example 1, trimellitic anhydride 1
92.1 f (1,0 mol), 4,4'-diaminodiphenyl meta 7198.3 f (1,0 mol)
, 300 m-cresylic acid (JIS K2451, equivalent to metacresol'rR1) was charged, and the reaction was carried out in the same manner as in Example 1. Foaming similar to Example 1 was 70~
When heated to 160°C, the fL9 was 20°C, unlike in Example 1.
It becomes opaque right after 5℃! It did not become transparent even after 75 hours had elapsed, and after t05 hours, the reaction temperature was raised to 220°C while some of the cresol was wetting out, and the reaction was started at 205°C for another 3 hours.The reaction was continued for a total of 8 hours, and it became transparent at 9 points. A solution was obtained. The wetted cresol t'129t.

At this point, 559t of cresol was added to stop the reaction.

The resulting resin solution was reddish-brown and transparent, had a nonvolatile content of 30.1% by weight, and a viscosity (30°C) of 93 voids. Example 1
When a coating film was formed on a copper plate under the same conditions as above, cracks occurred due to 1800 degrees of bending, and a flexible coating film could not be obtained.

Example 2 Using the same equipment and starting materials as Example 1, 200 to 20
The reaction was continued at a temperature of 5°C for 5 hours, then Cresol 4001 was added, the internal temperature was lowered to 120°C, 50f of diphenylsilanediol was added, the temperature was gradually raised, and the reaction was further continued at 200°C for 3 hours. A resin with a non-volatile content (200°C x 90 minutes) of 36% and a viscosity (25°C) of 34 poise was obtained.

The characteristics of the e* wire, which was obtained in the same manner as in Example 1 at a line speed of 12 m/min and has a T coating thickness of about 38 μm, are shown in Table 2 (Effects of the Invention). Amide-imide resin compositions have high molecular weight, excellent mechanical properties, heat softening properties, and excellent solubility. Modification with Mayo polyhydric alcohol increases the nonvolatile content and improves workability. It is possible to impregnate resin in addition to insulating paint,
It can be applied not only to electric insulating materials such as 8-layer boards, films, and adhesives, but also to the fields of heat-resistant paints, fibers, and molded resins, and is extremely useful in practice.

Claims (1)

[Claims] 1. A polycarboxylic acid or its derivative and a polyamine,
A polyamide-imide resin composition characterized by reacting a polyhydric alcohol with a reaction product obtained by reacting in the coexistence of a polyamide resin at an equivalent ratio of approximately 1:1. 2. The polyamide-imide resin composition according to claim 1, wherein the polycarboxylic acid or its derivative is an aromatic polycarboxylic acid. 3. The polyamide-imide resin composition according to claim 1 or 2, wherein the aromatic polycarboxylic acid is trimellitic anhydride. 4. The polyamide-imide resin composition according to any one of claims 1 to 3, wherein the polyamine is an aromatic diamine. 5. The polyamide-imide resin composition according to any one of claims 1 to 4, wherein the polyhydric alcohol is a polyhydric alcohol containing a trivalent or higher hydroxyl group in one molecule. 6. The polyamide-imide resin composition according to any one of claims 1 to 5, wherein the polyhydric alcohol is diphenylsilanediol. 7. The polyamide-imide resin composition according to any one of claims 1 to 6, wherein the blending ratio of the polyhydric alcohol is 5 to 40% by weight based on the resin content of the resin composition.