A novel functional monomer N-(2-Vinyloxyethyl)naphthalimide(VOENl) was synthesized and the photochemical behavior of its polymer was studied. With the electron-donating viny-loxyethyl group and the electron-accepting naphthalyl chromophore moiety coexisting in the same molecule

VOENI would form exciplex intermolecularly upon UV-irradiation and showed much lower fluorescence emission intensity compared with its polymer. Such a phenome-num was also termed as "Structural Self-Quenching Effect" similar to what had been reported previously in those structurally reversed cases of acrylinc monomers bearing oth electron-do-nating chromophore moiety and electron-accepting double bond in one molecule.