JPS59204609A - Polyamide-imide based resin composition - Google Patents

Abstract

PURPOSE:The titled composition, obtained by incorporating a polyamide-imide resin containing citric acid anhydride as a component with an aromatic polyimide resin soluble in phenolic solvents and a polyisocyanate stabilized with a phenolic compound, having improved softening temperature and width of baking conditions. CONSTITUTION:A composition obtained by incorporating (A) 100pts.wt. composition obtained by incorporating (i) a polyimide resin prepared by reacting an equimolar amount of an aromatic tetracarboxylic acid containing <=30mol% 3,3',4,4'-benzophenonetetracarboxylic acid with an equimolar amount of a diamine containing 30-60mol% aromatic diamine of formula I or II in a phenolic solvent under heating with (ii) a resin solution prepared by reacting an equimolar amount of an aromatic tricarboxylic acid anhydride containing >=5mol% citric acid anhydride with an equimolar amount of an aromatic diisocyanate in a phenolic solvent with (B) 5-70pts.wt. expressed in terms of polyisocyanate, polyisocyanate stabilized with a phenolic compound of formula III.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to a novel polyamide-imide resin composition.

(Technical background of the invention and its problems) As organic insulating materials used in electrical equipment, the use of imide group-containing resin coatings such as polyesterimide, polyamideimide, and polyimide, which have improved heat resistance, has been increasing in recent years. Among imide group-containing resins, polyamide-imide resin is known to have the best balance of heat resistance, mechanical properties, electrical properties, and chemical properties.

However, conventional aromatic polyamide-imide resins are only soluble in expensive organic polar solvents such as N-methyl-2-pyrrolidone and dimethylacetamide, which has resulted in the disadvantage of increasing the price of resin coatings.

Furthermore, since organic polar solvents have strong hygroscopicity, paints using organic polar solvents as solvents also have the disadvantage of being difficult to manage during storage and use.

For this reason, in the field of insulated wires, insulated Ti uses polyesterimide resin paint that sacrifices heat resistance to dissolve in relatively inexpensive phenolic solvents such as phenol, cresol, and xylenol;
Double-covered BL wires with polyesterimide iI4 resin paint on the bottom layer and polyamide-imide resin on the top layer are now mainly used, but insulated wires using polyamide-imide resin paint are not widely available. Because the characteristics are not balanced, the various requirements of current electrical equipment cannot be satisfied.

Therefore, many proposals have been made for polyamide-imide resins with excellent solubility in organic solvents that have been partially aliphatically modified by using amino acids, lactams, etc. as raw materials (for example, Honebun 11H56-17374, 56-22330S Special Publication No. 56-34210).

However, when aliphatic modification is performed in which a methylene chain is introduced into the molecule, as is the case with lactam, the heat resistance, especially the heat softening temperature when used as an insulated wire, is inferior to that of aromatic polyamideimide resin. The reality is that a resin with a good overall balance cannot be obtained.

The inventor of the present invention continued intensive studies to develop a polyamide-imide resin composition with excellent meltability, and as a result, by using citric acid, which has rarely been used as a material for heat-resistant resins, They discovered that it was possible to obtain a polyamide-imide resin composition that has superior heat softening properties than aromatic polyamide-imide resins and also has significantly improved meltability in organic solvents, and filed a patent application. (% Gansho 5
6-178289, etc.) However, the softening temperature of this product was not necessarily high enough to be satisfactory, and improvement thereof was desired. In addition, there was a drawback that baking conditions such as furnace temperature and baking speed had to be strictly controlled during baking. As a result of our investigation, we attempted to solve the above-mentioned problems by blending this polyamide-imide resin with a phenol solvent-soluble aromatic polyimide resin and a phenolic compound-stabilized polyisocyanate represented by the following general formula. It is something.

(Summary of the invention) The present invention was made based on the above knowledge, and includes (1)
Aromatic tetracarboxylic acids (including anhydrides and lower alkyl esters thereof) containing at least 30 moles of 3.3', 4,4'-benzophenone tetracarboxylic acid (including anhydrides and lower alkyl esters thereof). t
ro) 30 to 60 mol of the following general formula or (wherein, X is CH2,0, S02, C(CH3)2
or S, generally lower alkyl group, lower alkoxyl group, C0OH group, OH group, 80al
0 or less selected from i group or hapgen. ) of a polyimide resin solution obtained by heat-reacting approximately equal moles of diamines containing one or more aromatic diamines represented by (2) at least 5 moles of anhydrous in a phenolic solvent. The following general formula is applied to 100 parts by weight of a resin composition containing a resin solution obtained by reacting approximately equal moles of an aromatic tricarboxylic acid anhydride containing citric acid and an aromatic diisocyanate in a phenolic solvent. (However, W is an aromatic polyisocyanate residue, n is θ ~ 2, m is an integer from 1 to 4. The same applies hereinafter) is converted into the polyisocyanate content. 5 to 70 parts by weight of 3,3',4,4'-benzophenone tetracarboxylic acid used in the present invention may be added in addition to butodicarboxylic acid as it is, or its anhydride. or lower alkyl esters such as methyl ester and ethyl ester.

Aromatic tetracarboxylic acids other than 3,3',4,4'-benzophenonetetracarboxylic acid that can be used in the present invention include pyromellitic acid, 3.3',4,4'-benzophenonetetracarboxylic acid, and butanetetracarboxylic acid. carboxylic acid, 3
．． 3', 4.4'-diphenyltetracarboxylic acid, 2.
2',3.3'-diphenyltetracarboxylic acid, bicyclo(2,2,i)-off)-(7)-en-2,3,5
I. 6-tetodicarboxylic acid, 3.3', 4.4'-diphenyl ether tetracarboxylic acid, 2.2', 3.3
'-diphenyl ether tetracarboxylic acid, 1,4,5
,8-su7talentetracarboxylic acid, 2,3,6.7-
Naphthalenetetracarboxylic acid, 1,2,5.6-naphthalenetetracarboxylic acid, 2,2-bis(3,4-dicarboxyphenyl)sulfone, 2,5-bis(3,4-dicarboxyphenyl) 1, Examples include 3.4-oxadiazole and derivatives thereof such as anhydrides and esters thereof.

Examples of diamines represented by formulas [1] and (II') include 3,3'-diaminodiphenylmethane, 3,3'-diaminodiphenyl ether, 3,3'
-diaminodiphenylsulfone, 3,3'-diaminodiphenylpropane, 3,3'-diaminodiphenylsulfide, 2,4-diaminotoluene, 2,6-diaminotoluene, 1-isopropyl-2,4-metaphenylenediamine, l-ethoxy-2,4-diaminobenzene, l-epoxy-2,4-diaminobenzene, 2,
4-diaminobenzoic acid, 2.6-diaminobenzoic acid, 2
, 4-diaminophenol, 2,6-diamitfunol, ■-sulfo-2,4-diaminobenzene, 1-sulfo-2,6-diaminobenzene, 1-riOG! -2, 4
-diaminobenzene, l-chloro-2,4-diaminobenzene, l-7'Dmu-2,4-diaminobenzene, ■
-bromo2,6-cy7minobenzene, etc.

Furthermore, the above formula (1) and [l[) that can be used in the present invention
Aromatic diamines other than diamines represented by the formula include 4,4'-diaminodiphenylpropane, 4,
4'-diaminodiphenylmethane, 3゜3'-dichlorobenzidine, 4,4'-diaminodiphenylsulfide, 4,4'-diaminodiphenylsulfone,
4.4'-diaminodiphenyl ether, 1.5-diaminonaphthalene, metaphenylenediamine, paraphenylenediamine, 3°3'-dimethyl-4,4'-biphenyldiamine, 3.3'-dimethoxypentedine, 2,
4-bis(β-amino-t-butyl)toluene, 3,3
Examples include '-dimethyl-4,4'-diaminodiphenyl ether, 3,3'-dihydroxy-4,4'-diaminodiphenyl sulfone, and 3,3'-dimethoxy-4,4'-diaminodiphenylmethane.

As the aromatic tricarboxylic acid anhydride used in the present invention, those represented by the general formula can be used alone or in a mixture.

(However, X=-CH2-1-CO-1-80p, -1-C
(CH8)2-1-〇-) Trimellitic anhydride is generally preferred from the viewpoints of heat resistance, high reactivity, economic efficiency, etc.

In addition, in order to increase the imide bond ratio and improve heat resistance, a part of the aromatic tricarboxylic anhydride was replaced with pyromellitic anhydride, 3, 3', 4, 4' benzophenonetetracarboxylic anhydride, butanetetra It is also possible to substitute with a tetracarboxylic acid such as a carboxylic acid, or a derivative thereof.

On the other hand, if you want to increase the number of amide bonds from the standpoint of balancing the properties of a multi-component system, use terephthalic acid, isophthalic acid, oxalic acid, malonic acid, cobacic acid, ylutaric acid, adipic acid,
Aromatic acids such as pimelic acid, speric acid, and azelaic acid can also be used as part of an aromatic tricarboxylic acid anhydride.

If the amount of citric acid anhydride is less than 5 mol, the solubility in organic solvents, especially phenolic solvents will decrease, making it impossible to obtain a practical resin composition, so this specification was made.

The higher the ratio of citric acid, the higher the solubility in organic solvents.
Therefore, the ratio of citric acid can be arbitrarily changed within the above range depending on the form in which the resin composition of the present invention is used.

The aromatic diisocyanate used in the present invention is 4.
4'-diphenylmethane diisocyanate, 4-4'-
Diphenyl ether diisocyanate, 4-diphenylsulfone diisocyanate, 4,4'-diphenylsulfone diisocyanate, 3,3'-diphenylsulfone diisocyanate, 4,4'-dienylsulfide diisocyanate, 303'didimethyl- 41
4'-diphenylmethane diisocyanate, 3,3'-
Dichloro-4,4'-didiphenylmethane diisocyanate, 3113'-dimethyl-4,4'-bisphenyl diisocyanate, 3,3'-dimethoxy-4e4'-
bisphenyl diisocyanate, 4114'-bisphenyl diisocyanate), m-7 enylene diisocyanate, P-7 enylene diisocyanate'+2''4-) lylene diisocyanate, 2,6-lylene diisocyanate, m-xylylene diisocyanate, Aromatic diisocyanates such as P-xylylene diisocyanate can be used alone or in combination.

A part of the aromatic diisocyanate is aliphatic, fatty group'Z
It can also be replaced with a group diincyanate or a trivalent or higher valent polyisocyanate.

Generally, from the viewpoint of mechanical properties and economic efficiency of heat-resistant insulating coatings, 4,4'-diphenylmethane diisocyanate), 2.4
-) Lylene diisocyanate, 2゜6-lylene diisocyanate, m-xylylene diisocyanate, P-xylylene diisofuji 1-), 4,4'-diphenyl ether diisocyanate, etc., used alone or in combination of two types. It is desirable to do so.

The solvent used in the present invention is a phenolic solvent such as phenol cresol or xylenol.

Next, the preferred blending amounts of the coating materials (1) and (2) of the present invention are as follows: (1) polyimide resin solution 10 to 90 liters and (2) polyamideimide resin 90 to 90 liters.
It is preferable to add O in parts by weight.

If the polyimide resin solution is less than 10 parts by weight, a sufficient softening temperature will not be obtained, water resistance will not be sufficient, and 9 parts by weight will not be obtained.
If it exceeds 0 parts by weight, the crazing resistance will not be sufficient.

A suitable phenolic compound-stabilized polyisocyanate used in the present invention is a trimer of tolylene diisocyanate or a duplex of 4,4'-diphenylmethane diisocyanate having the following structure -NCO (I
n) etc. with phenol, cresol, xylenol, etc., and a urethane bond is added to the end. Among these stabilized polyisocyanates, stabilized aromatic polyisocyanates are particularly preferred in terms of heat resistance.

Furthermore, the stabilized diisocyanate represented by formula (IN) is likely to react with free carboxyl groups in the molecule.
-〇=N- bond, so it is preferable. It is preferred that the phenolic compound stabilized polyisocyanate be added at room temperature so that no dissociation of the stabilizer occurs. If the amount of phenolic compound-stabilized polyisocyanate added is small, the baking properties will not be improved; on the other hand, if it is too large, the deterioration resistance of the resulting enameled wire will be significantly reduced. It is preferable to add an isocyanate-stabilized isocyanate to 100 parts. (Examples of the Invention) The present invention will be explained below with reference to Examples.

[Reference Example 1 for producing polyimide resin] 145 g of 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 120 g of pyromellitic dianhydride
, 3,3'-diaminodiphenylsulfone 74,5 g
and 1500g of cresol for 31! The mixture was charged into a Mitsuro flask, and the temperature was gradually raised to 170° C. over about 1 hour while the water produced by the reaction was eluted out of the system to complete the reaction.

Next, a small amount of petroleum naphtha was added to adjust the resin content to 20%. 0.44 g of tetrabutyl titanate was added to the resin thus obtained.

[Manufacturing reference for polyamide-imide resin? TJ 2) Citric anhydride + 9.2g,) Limelitic anhydride 172.
8g, diphenylmethane diisocyanate 250.3
g and m-cresol 300g is 37? The mixture was placed in a Mitsuro flask and heated in a 200"Q trench for about 1 hour. Foaming and eluted water were observed from 70"C to 0.12"C at the reflux temperature of m-cresol. After reacting for a period of time, m-cresol was added to stop the reaction, and the unpressed portion (
200″0 x 90 minutes) 25% by weight resin solution.

(Example 1) 833 g of the resin obtained from Reference Example 1 and 667 g of the resin obtained from Reference Example 2 were uniformly mixed, and further 133 g of 4
Cresol-stabilized 4,4'-diaminodiphenylmethane diisocyanate containing 04'-diaminodiphenylmethane diisocyanate was gradually added as a No. 50 cresol solution while heating. The obtained resin solution was placed on a conductor wire with an outer diameter of 1.0 mmψ at a furnace length of 7 m and a furnace temperature of 390°C.
An insulated wire was manufactured by coating and baking in a baking furnace of "C" at a wire speed of 13 m/min.

(Example 2) 1250 g of the resin obtained from Reference Example 1 and 250 g of the resin obtained from Reference Example 2 were uniformly mixed to produce a desmodur CT containing 313 g of tolylene diisocyanate trimer.
Stable (trade name, manufactured by Bayer AG, West Germany) was added as a 50% by weight cresol solution in the same manner as in Example 1.

An insulated wire was manufactured from the obtained resin solution in the same manner as in Example 1.

(Example 3) 833 g of the resin obtained from Reference Example 1 and 667 g of the resin obtained from Reference Example 2 were uniformly mixed, and 133 g of the cresol stabilized diisocyanate represented by formula (1) was mixed with Example 1 and 667 g of the resin obtained from Reference Example 2. Added in the same way.

An insulated wire was produced from the obtained resin solution in the same manner as in Example 1.

(Example 4) 1250g of the resin obtained from Reference Example 1 and 250k of the resin obtained from Reference Example 2 were uniformly mixed, and 313g of [1]
A cresol stabilized diisocyanate represented by the formula was added in the same manner as in Example 1.

An insulated wire was manufactured using the obtained resin solution in the same manner as in Example 1.

(Comparative Example 1) An insulated wire was manufactured in the same manner as in Example 1 using the resin solution before adding the stabilized diisocyanate in Example 1.

(Comparative Example 2) An insulated wire was produced in the same manner as in Example 1 using a resin solution before adding the cresol stabilized diisocyanate represented by the formula IJ).

(Comparative Example 3) In Comparative Example 1, the knitting speed was set to the normal 10 m/min, and the insulation was 45! was manufactured.

The characteristics of the electric wires obtained in Examples 1 to 4 and Comparative Examples 1 to 3 are shown in the following table.

The following margin (effects of the invention) The resin composition of the present invention thus obtained exhibits extremely excellent solubility even in phenolic solvents due to the use of aromatic tricarboxylic acid anhydride containing anhydrous citric acid as an essential component. Moreover, the range of baking conditions can be widened.

Claims (1)

[Claims] 1. (1) 3.3', 4.4 of at least 30 molt.
'-Aromatic tetracarboxylic acid (including its anhydride and lower alkyl ester) containing tetracarboxylic acid (including its anhydride and lower alkyl ester) The following general formula (where X is CH2,0,80s, C(CH3)2
or S, R is a lower alkyl group, a lower alkoxyl group, a COOH group, an OH group, a 5OaH
or halogen. same as below. ) of a polyimide resin solution obtained by heat-reacting approximately equal moles of diamines containing one or more aromatic diamines represented by (2) at least 5 moles of anhydrous in a phenolic solvent. The following general formula is applied to 100 parts by weight of a resin composition containing a resin solution obtained by reacting approximately equal moles of an aromatic tricarboxylic acid anhydride containing citric acid and an aromatic diisocyanate in a phenolic solvent. (However, W represents an aromatic polyinsyanate residue, and n
is O~2, m is an integer from 1 to 4, and m is an integer from 1 to 4 (the same applies below 0), which is a phenolic compound-stabilized polyincyanate polyisocyanate O2, a phenolic compound-stabilized polyincyanate is expressed by the following general formula Ru. A polyamide-imide resin composition according to claim 1.