POLYSILYLENES WITH ETHYNYLPHENYL SUBSTITUENTS

Ethynylphenyl-methyldichlorosilane (EPDMS) has been prepared as a new monomer for the synthesis of polysilylenes with triple bonds attached to the catenated Si chain. A series of copolymers with methylphenyldic hlorosilane (MPDS) as well as the homopolymer, PEPMS, have been synthe sized. The content of ethynylphenyl substituents was quantitatively an alyzed by FTIR spectroscopy. The optical properties of the new polymer s were studied with respect to potential pi-sigma interaction. No sign ificant bathochromic shift of the UV-absorption maximum could be detec ted. Unexpectedly, increasing content of incorporated EPMS units led t o a decrease of the (sigma-sigma) absorption. The ethynylphenyl-subst ituted polysilylenes exhibited strong, temperature-dependent fluoresce nce in solution as well as in films.