광변색 비스 ( 벤조티오페닐 ) 에텐의 고분자 박막내에서의 여기상태의 구조 = Excited Structure of Photochromic Bis ( benzothiophenyl ) Ethene in Polymeric Membrane

다국어 초록 (Multilingual Abstract)

Photochromic properties and excited structure of his(benzothiophenyl)ethene (BTE) derivatives in a polymer network were investigated. Dicyanoethyl and maleic anhydride derivatives of BTE synthesized from thiophene were used as the BTE derivatives. Polystyrene (PS), polycarbonate (PC), polyethylene (PE), and sol-gel processed polisiloxane (SG) matrix were used as a polymeric host. Yellow colored BTE derivatives with an absorption band centered at 340-400 nm turned red upon irradiation with a light of 405 nm. The red colored ring-closed form showed absorption band centered at 540 nm, which was diminished by excitation with a light of 546 nm. Such a photochromic property was strongly dependent on the structure and composition of polymer host. Furthermore fluorescence spectra of BTHA doped PE, PS, PC, and SG film showed emission band centered at 506, 520, 529, 546 nm, respectively, The spectral shift was dependent on the polarity of the film and the large Stokes shift in the SG film could be attributed to the highly polar excited state structure of BTE.