Fluorescence polarization of N-vinyl carbazole grafted on cellulose acetate film and its electron transfer reaction with 1,4-dicyanobenzene

N-vinyl carbazole (VCZ) has been grafted on a cellulose acetate (CA) matrix by simultaneous irradiation technique using Co-60 gamma rays. Two sets of experiments, fluorescence polarization measurements with a grafted VCZ (GVCZ) film and a photo-induced electron transfer (ET) reaction between GVCZ and 1,4-dicyanobenzene (DCB) in tetrahydrofuran (THF), have been performed. Polarization appears in the GVCZ film due to restricted rotational motion of the grafted VCZ on a CA film. ET and the formation of an exciplex between GVCZ and DCB have been observed by steady state and time-resolved fluorescence and laser Bash photolysis studies. The dynamics of fluorescence quenching have been evaluated by applying the Stern-Volmer equation. Laser hash photolysis experiments have been able to identify the formation of DCB- at 430 nm due to ET from GVCZ to DCB, which adds a transient polyelectrolyte property to the system. (C) 1997 Elsevier Science Ltd.