JPH07238225A - Polyamide imide resin composition and insulated wire - Google Patents

Abstract

PURPOSE:To obtain a polyamide imide resin composition containing a polyamide imide resin and a specific compound, enabling high-speed baking without foaming, having excellent heat-resistance and abrasion resistance and useful for the coating material of insulated wire, etc. CONSTITUTION:This composition contains (A) a polyamide imide resin and (B) a compound of formula I [R1, R2, R4 and R5 each is H, a lower alkyl, phenyl or hydroxymethyl; R3 and R6 each is H, methyl or phenyl; X is a 1-8C alkylene, phenylene, vinylene, butadjenylene, (CH2)2-O-(CH2)2, (CH2)2-S-(CH2)2, NH-(CH2)2-S- S-(CH2)2-NH, group of formula II, group of formula III, etc.; (m) and (n) each is 0 or 1], e.g. 2,2'-bis(2-oxazoline). The amount of the component B is preferably 0.5-20wt.% based on the component A.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyamide-imide resin composition capable of high-speed baking and an insulated wire using the same.

[0002]

2. Description of the Related Art Conventionally, insulated electric wires (hereinafter abbreviated as enamel wires) obtained by coating and baking synthetic resin coatings such as polyvinyl formal, polyurethane, polyester, polyester imide, and polyamide imide on the conductor have their respective characteristics. Accordingly, it is used in various applications such as motors and transformers. Among them, polyamide-imide varnishes with good heat resistance, freon resistance and wear resistance are often used, but in recent years, in order to rationalize the production of enamel wire, the varnish for enameled wire has a rationalized production process in the baking process. There is a strong demand for high-speed seizure that corresponds to.

However, when high-speed baking is performed using a conventional synthetic resin paint using polyamide-imide, there has been a problem that the resin does not sufficiently have a high molecular weight and the heat softening temperature is lowered. Therefore, in order to solve the problem at the time of high-speed baking work, it has been studied to raise the baking temperature, but it has been found that raising the baking temperature causes a problem that the coating of the enameled wire foams.

[0004]

DISCLOSURE OF THE INVENTION The present invention provides a polyamide-imide resin composition and an insulated wire which do not foam during high-speed baking and does not lower the thermal softening temperature.

[0005]

The present invention has achieved the above object by adding a specific oxazoline compound to a polyamide-imide resin composition.

That is, the present invention relates to a polyamide-imide resin and the general formula (I).

[Chemical 3] [In the formula, R ₁ , R ₂ , R ₄ and R ₅ are each independently hydrogen,
Selected from the group consisting of a lower alkyl group, a phenyl group and a hydroxymethyl group, R ₃ and R ₆ are each independently selected from the group consisting of hydrogen, a methyl group and a phenyl group,
n is an integer of 0 or 1, X is an alkylene group having 1 to 8 carbon atoms, a phenylene group, vinylene group, butadienylene _{group, -CH 2 -CH 2 -O-CH} 2 -CH 2 -, - CH 2 -
_{CH 2 -S-CH 2 -CH 2} -, - NH-CH 2 -CH 2 -
_{-NH- S-S-CH 2 -CH} 2,

[Chemical 4] Selected from the group consisting of, m is an integer of 0 or 1]
The present invention relates to a polyamide-imide resin composition containing a compound represented by and an insulated electric wire obtained by applying and baking the polyamide-imide resin composition on a conductor directly or via another insulator.

Polyamideimide resin is disclosed in Japanese Patent Publication No. 44-19
It is produced by a known production method disclosed in Japanese Patent Publication No. 274, etc., and is obtained, for example, by reacting a tricarboxylic or higher polycarboxylic acid having an acid anhydride group or a derivative thereof with an aromatic diisocyanate in a polar solvent. .

As the tricarboxylic or higher polycarboxylic acid having an acid anhydride group or a derivative thereof, for example, a compound represented by the general formula (II) or (III) can be used,

[Chemical 5] [Wherein R represents hydrogen, an alkyl group or a phenyl group, and Y represents —CH ₂ —, —CO—, —SO ₂ — or —O.
-] A trivalent or higher polycarboxylic acid having an acid anhydride group that reacts with an isocyanate group or a derivative thereof may be used without any particular limitation. If necessary, a part of this is pyromellitic dianhydride, benzophenonetetracarboxylic dianhydride,
Butanetetracarboxylic dianhydride, bicyclo- [2,
2,2] -Oct-7-ene-2: 3: 5: 6-tetracarboxylic dianhydride and the like, or an aliphatic or aromatic dibasic acid may be substituted. Generally, trimellitic anhydride is most preferable in consideration of heat resistance and cost.

As the aromatic diisocyanate, for example, 4,4'-diphenylmethane diisocyanate, tolylene diisocyanate, xylylene diisocyanate, 4,4'-diphenyl ether diisocyanate and the like can be used, and these can also be used in combination. it can. Pre-synthesized polyisocyanate may be used, or those stabilized with a suitable blocking agent may be used to avoid aging.

The amounts of the above polycarboxylic acid or its derivative and the aromatic diisocyanate are selected so that the ratio of the isocyanate group to the carboxyl group or its derivative group and the acid anhydride group is 1.5 to 0.7. In order to obtain a high molecular weight resin, it is preferable to set the ratio of the isocyanate group to the carboxyl group or its derivative group and the acid anhydride group to around 1.0. The reaction is 80
In the temperature range of 150 ° C to 150 ° C, heat condensation is performed in the presence of a polar solvent while removing carbon dioxide which is liberated from the reaction system. The reaction time is appropriately selected depending on the scale of the batch and the reaction conditions adopted. As the polar solvent, a chemically inert organic solvent such as N-methyl-2-pyrrolidone,
N, N-dimethylformamide, N, N-dimethylacetamide, dimethylsulfoxide and the like can be used, and the amount thereof is preferably 1.0 to 3.0 times (weight) of the produced polyamideimide resin. After the synthesis of the polyamide-imide resin is completed, the isocyanate group at the resin terminal can be blocked with a blocking agent such as alcohols and lactams.

The polyamide-imide resin composition of the present invention contains the compound represented by the general formula (I) together with the polyamide-imide resin obtained as described above. Here, examples of the compound represented by the general formula (I) include 2,2′-bis (2-oxazoline), 5,5′-dimethyl-2,2′-bisoxazoline, 4,4,4. 4 ', 4'-tetramethyl-2,2'-bisoxazoline, 4,4'-diethyl-2,2'-bisoxazoline, 2,2'-methylenebis (2-oxazoline), 2,2'-ethylene Bis (2-oxazoline), 2,2'-ethylenebis (4,4-dimethyl-2)
-Oxazoline), 2,2'-trimethylenebis (4,
4-dimethyl-2-oxazoline), 2,2'-tetramethylenebis (4,4-dimethyl-2-oxazoline), 2,2'-pentamethylenebis (4,4-dimethyl-2-oxazoline), 2 , 2'-hexamethylenebis (4,4-dimethyl-2-oxazoline), 2,2 '
-Heptamethylenebis (4,4-dimethyl-2-oxazoline), 2,2'-octamethylenebis (4,4-dimethyl-2-oxazoline), 2,2'-ethylenebis (4-methyl-2-) Oxazoline), 2,2'-trimethylenebis (4-methyl-2-oxazoline), 2,
2'-tetramethylene bis (4-methyl-2-oxazoline), 2,2'-pentamethylene bis (4-methyl-
2-oxazoline), 2,2'-hexamethylenebis (4-methyl-2-oxazoline), 2,2'-heptamethylenebis (4-methyl-2-oxazoline), 2,
2'-tetramethylenebis (5-methyl-2-oxazoline), 2,2'-tetramethylenebis (4,4-diphenyl-2-oxazoline), 2,2'-tetramethylenebis-2-oxazoline-4 -Methanol, 2,2 '
-Tetramethylenebis-2-oxazoline-4,4'-
Dimethanol, 2,2'-tetramethylenebis-2-oxazoline, 2,2'-octamethylenebis-2-oxazoline, 2,2'-tetramethylenebis [4- (hydroxymethyl) -4-methyl-oxazoline ], 2,
2'-heptamethylenebis [4- (hydroxymethyl)
-4-Methyl-oxazoline], 2,2'-octamethylenebis [4- (hydroxymethyl) -4-methyl-oxazoline], 2,2'-vinylenebis (5-methyl-
2-oxazoline), 2,2 '-(1,3-butadienylene) bis-2-oxazoline, 2,2'-(oxydiethylene) di-2-oxazoline, 2,2 '-[ethylenebis (oxyethylene) ] Bis-2-oxazoline,
2,2 '-[propylenebis (oxyethylene)] bis-2-oxazoline, 2,2'-(1,3-phenylene) bis (2-oxazoline), 2,2'-p-phenylenebis-2- Oxazoline, 2,2'-p-phenylene bis (4,4-dimethyl-2-oxazoline), 2,
2'-p-phenylene bis (5-phenyl-2-oxazoline), 2,2 '-(oxydi-p-phenylene) bis-2-oxazoline, 2,2'-[oxybis (p-
Phenylene methylene)] bis-2-oxazoline, 2,
2 '-[((2-aminoethyl) imino) dimethylene]
Bis-2-oxazoline, 2,2 ′-(thiodiethylene) bis-2-oxazoline, 2,2 ′-[dithiobis (ethyleneimino)] di-2-oxazoline, 2,2 ′
-[Dithiobis (ethyleneimino)] bis (4-methyl-5-phenyl-2-oxazoline), 2,2 '-[dithiobis (ethyleneimino)] bis (4,4-dimethyl-2-oxazoline), 2, 2 ', 2 "-(nitrilotrimethylene) tris-2-oxazoline, 1,2,4-
Examples thereof include tri (2-oxazolin-2-yl) benzene.

The amount of the compound represented by the general formula (I) used is
Due to the high-speed baking workability, it is 0.
It is preferably 5 to 20% by weight.

As a method of adding the compound represented by the general formula (I), the compound to be added may be dissolved in the same solvent as the solvent contained in the polyamideimide resin composition in advance and then added. It may be added directly to the polyamide-imide resin composition.

The polyamide-imide resin composition according to the present invention is prepared by using a polar organic solvent such as N-methyl-2-pyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide and dimethyl sulfoxide to obtain a resin component 20.
It can be diluted to -40% by weight and used as a solution. In this case, xylene and NISSEKI HISOL-10 are used as cosolvents in consideration of the resin content concentration and viscosity.
0, 150, cellosolve acetate, ethylbenzene,
You may use p-cymene etc. together.

An epoxy resin and / or an amine-based additive may be added to the polyamide-imide resin composition of the present invention in order to improve its curability. The epoxy resin is not particularly limited, and examples thereof include Epicoat 815, 825, 827 manufactured by Yuka Shell Epoxy Co., Ltd.
828, 834, 1001, 1004, 1007, 10
09 bisphenol A type epoxy resin, Epicoat 152, 154, Nippon Kayaku Co., Ltd. EPPN-201,
Phenol novolac type epoxy resin such as DEN-438 manufactured by Dow Chemical Co., Ltd., EOCN-1 manufactured by Nippon Kayaku Co., Ltd.
02S, 103S, 104S and other o-cresol novolac type epoxy resins, Ep manufactured by Yuka Shell Epoxy Co., Ltd.
on1031S, Ciba Geigy Araldite 016
3, Denacol EX-611 manufactured by Nagase Kasei Co., Ltd.,
EX-614, EX-614B, EX-622, EX-
512, EX-521, EX-421, EX-411,
Multifunctional epoxy resin such as EX-321, Tohto Kasei Co., Ltd.
YH-434 manufactured by Mitsubishi Gas Chemical Co., Ltd. TETRAD-
Amine type epoxy resins such as X, TETRAD-C, GAN manufactured by Nippon Kayaku Co., Ltd., ELM-120 manufactured by Sumitomo Chemical Co., Ltd., heterocyclic ring-containing epoxy resins such as Araldite PT810 manufactured by Ciba-Geigy, ERL4234, 42 manufactured by UCC.
Alicyclic epoxy resins such as 99, 4221 and 4206 can be used, and one or more of these can be used.

As the amine-based additive, for example, 4,
4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, primary amines such as p-phenylenediamine, secondary amines such as piperidine and pyrrolidine,
N, N, N ', N'-tetramethylhexamethylenediamine, N, N, N', N'-tetramethylpropylenediamine, N, N, N ', N ", N" -pentamethyldiethylenetriamine, trimethylamino Ethylpiperazine, N, N'-dimethylcyclohexylamine, bis (2-dimethylaminoethyl) ether, N, N ',
N "-tris (3-dimethylaminopropyl) hexahydro-s-triazine, N, N-dimethylbenzylamine, N-methylmorpholine, N-ethylmorpholine, N
-Trioxyethylene-N, N-dimethylamine, triethylenediamine, 1,8-diaza-bicyclo (5,5
4,0) Undecene-7, N, N, N-tris (3-dimethylaminopropyl) amine, N-methyldicyclohexylamine, N-methyl-N- (dimethylaminopropyl) aminoethanol, N-methyl-N, N-bis (3-dimethylaminopropyl) amine, 2- (dimethylaminomethyl) phenol, 2,4,6-tris (dimethylaminomethyl) phenol, N, N'-dimethylpiperazine, pyridine, picoline, 1,2 , 2, 6, 6
-Pentamethyl-4-piperidinol, tertiary amines such as triethylamine and the like can be used.

An insulated wire can be obtained by applying and baking the polyamide-imide resin composition of the present invention onto a conductor directly or via another insulator. The polyamide-imide resin composition according to the present invention is mainly used as a varnish for enameled wire, but for other purposes, for example,
It can also be used as a sheet varnish combined with a base material such as an impregnating varnish for electric insulation, a cast varnish, mica and glass cloth, a varnish for MCL laminated plate, a varnish for friction material and the like.

[0018]

EXAMPLES Next, the present invention will be explained in detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

Comparative Example 1 N-methyl-2-pyrrolidone 7 was placed in a 2-liter four-necked flask equipped with a stirrer, a cooling tube, a nitrogen introducing tube and a thermometer.
Charged 47 g (1.19 mol), 4,4′-diphenylmethane diisocyanate 298 g (1.19 mol) and trimellitic anhydride 227 g (1.18 mol), 13
The temperature was raised to 0 ° C. After reacting for about 4 hours, a resin having a number average molecular weight of 17,000 was obtained. After the terminal of this resin was sealed with methanol, it was diluted with a mixed solvent of 70 parts by weight of N-methyl-2-pyrrolidone and 30 parts by weight of N, N-dimethylformamide to give a polyamideimide resin varnish having a nonvolatile content of 30% by weight. Obtained.

Example 1 1,3-P was added to 100 parts by weight of the resin component of the polyamide-imide resin varnish obtained by the same method as in Comparative Example 1.
3.0 parts by weight of BO [trade name of 2,2 ′-(1,3-phenylene) bis (2-oxazoline) manufactured by Takeda Pharmaceutical Co., Ltd.] is added to 70 parts by weight of N-methyl-2-pyrrolidone and N,
A solution diluted with a mixed solvent of 30 parts by weight of N-dimethylformamide to a nonvolatile content of 30% by weight was added, and a nonvolatile content of 30% was obtained.
A weight% polyamide-imide resin composition was obtained.

Example 2 Except that the amount of 1,3-PBO added was 5.0 parts by weight,
The same operation as in Example 1 is carried out to obtain a nonvolatile content of 30% by weight.
A polyamide-imide resin composition of was obtained.

Example 3 1,3-P was added to 100 parts by weight of the resin component of the polyamide-imide resin varnish obtained in the same manner as in Comparative Example 1.
3.0 parts by weight of BO and 3.0 parts by weight of Epon 1031S (trade name of tetrafunctional epoxy resin manufactured by Yuka Shell Epoxy Co., Ltd., epoxy equivalent 206) were added to 70 parts by weight of N-methyl-2-pyrrolidone and N, N-. Dimethylformamide 30
A solution diluted with 1 part by weight of a mixed solvent is added, and the nonvolatile content 3
0% by weight of polyamide-imide resin composition was obtained.

Example 4 Except that the amount of 1,3-PBO added was 0.4 parts by weight,
The same operation as in Example 1 is carried out to obtain a nonvolatile content of 30% by weight.
A polyamide-imide resin composition of was obtained.

The polyamide-imide resin compositions obtained in the above Comparative Examples and Examples were baked on a conductor to form an enamel wire, the characteristics of which were measured by the following methods, and the results are shown in Table 1.
The baking of the enamel wire was performed under the following conditions. Wire diameter 1mm, 1 type finish, 8 times die coating

Characteristic Test Appearance The degree of foaming was visually evaluated by the following criteria. ◎ No foaming ○ No foaming (slightly rough surface) × Foaming Flexibility and softening resistance were measured according to JIS-C3003 (mandrel winding, 20% elongation).

[0026]

[Table 1]

From the results shown in Table 1, the enamel wire obtained by baking the polyamide-imide resin composition of the present invention on a conductor does not cause foaming even if it is baked at high temperature and high speed, and the characteristics of the obtained enamel wire (acceptable). It is shown that flexibility and softening resistance) do not decrease.

[0028]

EFFECTS OF THE INVENTION According to the polyamide-imide resin composition of the present invention, foaming does not occur during high-speed baking work, and the characteristics of the obtained enameled wire are not deteriorated.
The productivity of the enameled wire can be significantly improved.

Claims (4)

[Claims] 1. A polyamide-imide resin and a compound represented by the general formula (I): [In the formula, R ₁ , R ₂ , R ₄ and R ₅ are each independently hydrogen,
Selected from the group consisting of a lower alkyl group, a phenyl group and a hydroxymethyl group, R ₃ and R ₆ are each independently selected from the group consisting of hydrogen, a methyl group and a phenyl group,
n is an integer of 0 or 1, X is an alkylene group having 1 to 8 carbon atoms, a phenylene group, vinylene group, butadienylene _{group, -CH 2 -CH 2 -O-CH} 2 -CH 2 -, - CH 2 -
_{CH 2 -S-CH 2 -CH 2} -, - NH-CH 2 -CH 2 -
_{S-S-CH 2 -CH 2} -NH-, ## STR2 ## Selected from the group consisting of, m is an integer of 0 or 1]
A polyamide-imide resin composition containing a compound represented by: 2. The polyamide-imide resin composition according to claim 1, which contains the compound represented by the general formula (I) in an amount of 0.5 to 20% by weight based on the polyamide-imide resin. 3. A resin content of 20 to 40 depending on the polar organic solvent.
The polyamide-imide resin composition according to claim 1 or 2, which is diluted to a weight percentage. 4. An insulated wire obtained by applying and baking the polyamideimide resin composition according to claim 1 on a conductor directly or via another insulator.