Coating solution of polyetherimide oligomers

Claim 2

A coating solution including oligomeric polyetherimides formed by: (a) reacting at least one aromatic bis(ether anhydride) of the formula: ##STR10## with less than a stoichometric amount of at least one diamine of the general formula: H.sub.2 N--R.sup.1 --NH.sub.2 in a suitable solvent to form oligomeric polyetheramic acids containing terminal anhydride groups; (b) heating the solution of (a) to a temperature between 80° C. and 250° C. to form oligomeric polyetherimide anhydrides; (c) hydrolizing the oligomeric anhydrides of (b) to form the free acids of the formula: ##STR11## (d) adding to the oligomer solution of (c) more of the same or different diamine, and optionally more solvent and water, where R is a member selected from the class consisting of (A) divalent organic radicals having the following formulas: ##STR12## and (B) divalent organic radicals of the general formula: ##STR13## where m is 0 or 1 and X is a member selected from the class consisting of divalent radicals of the formulas, ##STR14## where y is an integer from 1 to 4; R 1 is a divalent organic radical selected from the class consisting of (a) aromatic hydrocarbon radicals having from 6 to about 20 carbon atoms and haloginated derivatives thereof, (b) alkylene radicals having from 2 to about 20 carbon atoms, and cycloalkylene radicals having from 3 to about 30 carbon atoms, (c) from C 2 to about C 8 alkylene terminated polydiorganosiloxane, and (d) divalent radicals of the general formula: ##STR15## where m is as previously defined and Q is a member selected from the class consisting of ##STR16## where x is an integer from 1 to 5 inclusive; and n is an integer from 0 to 100.

Claim 3

The coating solution of claim 1 wherein the diamine is used in a ratio of between 0.5 and 0.2 moles diamine per mole of dianhydride.

Claim 4

The coating solution of claim 1 wherein the diamine is used in a ratio of between 1.0 and 1.2 moles diamine per mole of dianhydride.

Claim 5

The coating solution of claim 1 where the aromatic bis(ether anhydride) is ##STR17## where R 2 is ##STR18## and Q 1 is selected from ##STR19##

Claim 6

The coating solution of claim 1 where the aromatic bis(ether anhydride) is ##STR20## where R 2 is ##STR21## and Q 1 is selected from ##STR22##

Claim 7

The coating solution of claim 1 where the organic diamine is methylene dianiline.

Claim 8

The coating solution of claim 1 where the organic diamine is oxydianiline.

Claim 9

The coating solution of claim 1, where the aromatic bis(ether anhydride) is 2,2-bis[4-3(3,4-dicarboxyphenoxy)phenyl]propane dianhydride and the organic diamine is 4,4'-methylenedianiline.

Claim 10

A process for preparing a coating solution which includes oligomeric polyetherimides comprising: (a) reacting at least one aromatic bis(ether anhydride) of the formula: ##STR23## with less than a stoichometric amount of at least one diamine of the general formula: H.sub.2 N--R.sup.1 --NH.sub.2 in a suitable solvent to form oligomeric polyetheramic acids containing terminal anhydride groups (b) heating the solution of (a) to a temperature between 80° C. and 250° C. to form oligomeric polyetherimide anhydrides (c) hydrolizing the oligomeric anhydrides of (b) to form the free acids of the formula: ##STR24## (d) adding to the oligomer solution of (c) more of the same or different diamine, and optionally more solvent and water, where R is a member selected from the class consisting of (A) divalent organic radicals having the following formulas: ##STR25## and (B) divalent organic radicals of the general formula: ##STR26## where m is 0 or 1 and X is a member selected from the class consisting of divalent radicals of the formulas, ##STR27## where y is an integer from 1 to 4; R 1 is a divalent organic radical selected from the class consisting of (a) aromatic hydrocarbon radicals having from 6 to about 20 carbon atoms and haloginated derivatives thereof, (b) alkylene radicals having from 2 to about 20 carbon atoms, and cycloalkylene radicals having from 3 to about 30 carbon atoms, (c) from C 2 to about C 8 alkylene terminated polydiorganosiloxane, and (d) divalent radicals of the general formula: ##STR28## where m is as previously defined and Q is a member selected from the class consisting of ##STR29## where x is an integer from 1 to 5 inclusive, and n is an integer from 0 to 100.

Claim 11

A process for preparing a coating solution which includes oligomeric polyetherimides comprising: (a) reacting at least one aromatic bis(ether anhydride) of the formula: ##STR23## with less than a stoichometric amount of at least one diamine of the general formula: H.sub.2 N--R.sup.1 --NH.sub.2 in a suitable solvent to form oligomeric polyetheramic acids containing terminal anhydride groups (b) heating the solution of (a) to a temperature between 80° C. and 250° C. to form oligomeric polyetherimide anhydrides (c) hydrolizing the oligomeric anhydrides of (b) to form the free acids of the formula: ##STR24## (d) adding to the oligomer solution of (c) more of the same or different diamine, and optionally more solvent and water, where R is a member selected from the class consisting of (A) divalent organic radicals having the following formulas: ##STR25## and (B) divalent organic radicals of the general formula: ##STR26## where m is 0 or 1 and X is a member selected from the class consisting of divalent radicals of the formulas, ##STR27## where y is an integer from 1 to 4; R 1 is a divalent organic radical selected from the class consisting of (a) aromatic hydrocarbon radicals having from 6 to about 20 carbon atoms and haloginated derivatives thereof, (b) alkylene radicals having from 2 to about 20 carbon atoms, and cycloalkylene radicals having from 3 to about 30 carbon atoms, (c) from C 2 to about C 8 alkylene terminated polydiorganosiloxane, and (d) divalent radicals of the general formula: ##STR28## where m is as previously defined and Q is a member selected from the class consisting of ##STR29## where x is an integer from 1 to 5 inclusive, and n is an integer from 0 to 100.