Patent ID: 6979721

Claim:
Polyimides having improved thermal-oxidative stability derived from the polymerization of effective amounts of at least one polyamine, at least one tetracarboxylic dianhydride and a dicarboxylic endcap having a formula: wherein R 1 is selected from the group consisting of an alkyl, fluoroalkyl, aryl, fluoroaryl, OR, carboxy, nitro, cyano, R—N—R, SO 3 R, PO 4 R, F and Cl radicals where R is selected from the group consisting of hydrogen, an aryl radical, and an alkyl radical of 1 to 6 carbons; and wherein R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8 are the same or different radicals selected from the group consisting of hydrogen, alkyl, fluoroalkyl, aryl, fluoroaryl, OR, carboxy, nitro, cyano, R—N—R, SO 3 R, PO 4 R, F and Cl radicals where R is selected from the group consisting of hydrogen, an aryl radical, and an alkyl radical of 1 to 6 carbon atoms.