Tunable emission of a tetraphenylethylene copolymer via polymer matrix assisted and aggregation-induced emission

A novel polyacrylamide (PAM) copolymer possessing tetraphenylethylene (TPE) AIEgens was synthesized, which exhibited tunable fluorescence emission under different solvent conditions. Different from traditional AIEgens showing strong fluorescence in poor solvents but relatively weak emission in good solvents, the present polymers are emissive under both circumstances. The mechanism was due to the fact that hydrogen bonding in the copolymer matrix played an important role in providing a rigid environment and blocking the non-radiative pathway thereby strengthening fluorescence emission under certain conditions. The different solution ratios of H2O/DMF had a great impact on the fluorescence intensity of the polymer. Moreover, the ternary copolymer incorporating Rhodamine B (RhB) and TPE into the PAM exhibited tunable and multicolor emissions including a white-light one in solvents with various ratios of H2O/DMF.