Synthesis and Characterization of Hyperbranched Poly(siloxysilane) Possessing Rhodamine B as Terminal Group

The hyperbranched poly(siloxysilane) possessing rhodamine B (HBPS-RB) group on the terminal position was synthesized by esterification of hyperbranched poly(siloxysilane) with hydroxyl terminal group and RB in the presence of DCC and DMAP. Two derivative hyperbranched poly(siloxysilane)s containing vinyl(HBPS-V) and hydroxyl (HBPS-OH) terminal groups were prepared by hydrosilylation of bis(dimethylvinylsilyl) methylsiloxane(AB2) and radical addition of 2-mercaptoethanol using AIBN as initiator, respectively. The structures of the polymers were characterized by the 1H NMR, 13C NMR and Fourier Transform Infrared (FT-IR) spectra. The molecular weights were measured by gel permeation chromatography (GPC). The UV-Visible absorption spectra indicate that 34% RB was conjugated to polymer. Fluorescence spectrum indicated that aggregation of RB was depressed in the polymer because RB molecules were separated by branch of polymer molecules.