OPTICALLY REFLECTIVE POLYIMIDE FILMS CREATED BY IN-SITU SILVER METAL FORMATION

Polyimide precursors can be doped with organometallic complexes for the purpose of obtaining useful electrical, mechanical, etc., properties which are not charactertistic of either component materials. In this regard, flexible, highly reflective silver-containing polyimide films have been prepared by incorporating (1,5-cyclooctadienehexafluoroacetylacetonato)-silver(I) [Ag(COD)(HFA)] into various poly(amide acids). A variation in optical properties of the films was observed that depended upon the type of diamine-dianhydride monomer employed. Films derived from 3,3',4,4'-benzophenone tetracarboxylic acid dianhydride (BTDA) when cured in air exhibited good thermal stability and reflectivity as high as 65% regardless of the diamine used. 4,4'-Bis(3,4-dicarboxyphenoxy)diphenyl sulfide dianhydride (BDSDA) in conjunction with various diamines yielded cloudy films when cured in air. Characterization of these films and our understanding of the influence of polymer structure on surface properties is discussed.