Modified rhodamine 6G molecules (Rh-Al)with polymerizable double bonds were copolymerized with methyl methacrylate(MMA) and 1

8-naphthalimide derivative(N-AE).The structures of the two monomers(Rh-Al and N-AE)were confirmed and characterized by 1H-NMR and MS. The UV-Vis absorption spectra of the copolymer indicate that there is little or no interaction between the two chromophores in their ground state. However

the fluorescence emission of N-AE was partly quenched and the fluorescence emission of Rh-Al was enhanced in the copolymer.While the fluorescence emissions of N-AE and Rh-Al both were partly quenched in the corresponding mixture.The results show that in the excited state exists very effective intramolecular singlet-singlet energy transfer(Intra-SSET)channel from N-AE to Rh-Al in the copolymer.The experiments seem to indicate that the covalent binding of the chromophore to a polymer chain restricts its mobility and

therefore

hinders the internal micromotions of the excited groups

avoiding non-fluorescent deactivation and thus increasing its emission efficiency and photostability.