Polyetherimide copolymers

Claim 1

A polyetherimide copolymer which comprises repeating polyimide units of the formula ##STR12## and repeating polyetherimide units of the formula ##STR13## wherein R 1 is selected from the group represented by the following formulas: ##STR14## where R 2 is an alkyl radical of from 1 to 4 carbon atoms, provided that from about 1% to about 90% of the groups in the copolymer represented by R 1 are selected from formulas I-III and from about 99% to about 1% of those groups are selected from the formulas IV-VII; M is selected from the group consisting of ##STR15## wherein B is --S-- or ##STR16## --O--Z--O-- may be in the 3 or 3'- and 4 or 4'- positions and Z is a member of the class consisting of (1) ##STR17## and (2) divalent organic radicals of the general formula: ##STR18## where X is a member selected from the class consisting of divalent radicals of the formulas, --C y H 2y --, ##STR19## --O-- and --S--, where q is 0 or 1, y is a whole number from 1 to 5, and wherein the copolymer contains from about 10 to about 10,000 of the polyimide and polyetherimide repeating groups.