Patent ID: 8974903
Filing Date: 2015-03-10
Classification: C08G,C08J,C08L,Y10T

Abstract:
1. A porous cross-linked polyimide-urea network comprising a subunit comprising two anhydride end-capped polyamic acid oligomers in direct connection via a urea linkage, wherein: (i) the oligomers (a) each comprise a repeating unit of a dianhydride and a diamine and a terminal anhydride group and (b) are formulated with 2 to 15 of the repeating units; (ii) the subunit was formed by reaction of the diamine and a diisocyanate to form a diamine-urea linkage-diamine group, followed by reaction of the diamine-urea linkage-diamine group with the dianhydride and the diamine to form the subunit; (iii) the subunit has been cross-linked via a cross-linking agent, comprising three or more amine groups, at a balanced stoichiometry of the amine groups to the terminal anhydride groups; and (iv) the subunit has been chemically imidized to yield the porous cross-linked polyimide-urea network.