VINYL MONOMERS BEARING CHROMOPHORE MOIETIES AND THEIR POLYMERS - V - SYNTHESIS AND FLUORESCENCE BEHAVIOR OF A VINYLOXY MONOMER BEARING ELECTRON-ACCEPTING CHROMOPHORE MOIETY, N-(2-(VINYLOXY)ETHYL)-1,8-NAPHTHALIMADE, AND ITS POLYMER

A vinyloxy monomer bearing electron-accepting chromophore, N-(2-(vinyl oxy) ethyl)-1,8-naphthalimide (VOENI), was synthesized by reaction of potassium 1,8-naphthalimide with 2-chloroethyl vinyl ether. VOENI carl be homopolymerized by cationic initiation and copolymerized with male ic anhydride (MAn) under radical initiation. The fluorescence behavior s of VOENI and its polymers were investigated. It has been found that the fluorescence intensity of the VOENI monomer is much lower than tha t of its polymers at the same chromophore concentration. This means th at a ''structural self-quenching effect'' (SSQE) has been also observe d in the vinyloxy monomer consisting of an electron-accepting chromoph ore, which has opposite electronic structure in comparison with acryla tes bearing electron-donating chromophores as we have reported previou sly. The SSQE is attributed to the charge-transfer interaction between the electron-accepting chromophore and the electron-donating double b ond in the same molecule. The fluorescence quenching of 1,8-naphthalic anhydride and P(VOENI-co-MAn) by ethyl vinyl ether (EVE), dihydrofura n, triethylamine (TEA), etc. evidences that the electron-rich vinyloxy group does act as an important role in the SSQE of VOENI. C-60 can al so quench the fluorescence of the polymers, and an upward deviation fr om the linearity of the Stern-Volmer plot was observed showing that C- 60 acted as a powerful electron donor to quench the fluorescence of th e copolymer. (C) 1998 John Wiley & Sons, Inc.