Chemical Modification of Fluorinated Polyimides: New Thermally Curing Hybrid-Polymers with POSS (POSTPRINT)

摘要

A series of four new end-capped and hydroxymethyl-functionalized polyimides were prepared. Through a two-step chemical modification process 3- aminopropylisobutyl-POSS was covalently attached to the polymer backbone. POSS loading levels as high as 40 wt-% could be obtained while maintaining excellent processability and optical clarity of thin films. Concurrent attachment of either a cyanate ester or hydroxyethyl methacrylate (HEMA) group afforded processable POSS-polyimides that underwent thermal curing to yield solvent resistant films, both having final Tg's of 251 deg. C. Kinetic analysis of the cure reactions yielded energy of activations of 93 kJ/mol (cyanate ester) and 103 kJ/mol (HEMA). Exposure of a POSS polyimide containing approximately 31 wt-% POSS to atomic oxygen displayed no measurable level of erosion relative to a Kapton(registered) standard.