Photoactivated hydrosilation curing of a ceramic precursor: Crosslinking and pyrolysis of branched oligo[(methylsilylene)methylene]

The complex bis(acetylacetonato)platinum(II) was activated by UV light in Liquid mixtures of oligo[(methylsilylene)methylene] (OMSM) leading to rapid solidification and the formation of polycarbosilane with a crosslinked structure. A hydrosilation catalyst is produced by irradiation of this complex which promotes chain extension at OIL?SM silicon hydride sites with the additive tetravinylsilane. Dihydridosilicon end groups on the oligomer are necessary for rapid photocuring. The crosslinked polymers were pyrolyzed under inert conditions giving 70% yields of beta-silicon carbide ceramic char with an overall carbon to silicon ratio of 1.79 to 1. Films of OMSM resin were spin-coated onto silicon wafers, cured, and pyrolyzed. Images on the film surfaces were retained in shape and dimension after pyrolysis. (C) 1997 Elsevier Science S.A.