Preparation and characterization of crosslinked polyimide-poly(dimethylsiloxane)s

Crosslinked polyimide-poly(dimethylsiloxane)s with theoretical content of t he siloxane phase up to 60 wt% were prepared. The starting materials were p -aminophenyltrimethoxysilane terminated polyamic acids with number average molecular weight of 10,000 g mol(-1), based on 4,4'-oxydiphthalic anhydride and 4,4'-oxydianiline and dimethoxydimethylsilane. The structure of the pr epared polymeric materials was analyzed using Si-29 and C-13 NMR solid-stat e spectroscopy. Their thermal and mechanical properties, chemical resistanc e and density were evaluated. The influence of the basic catalysts employed (ammonium hydroxide) on the course of the reaction and properties of the m aterials was also studied. (C) 2001 Elsevier Science Ltd. All rights reserv ed.