Polymerization of N‐vinylcarbazole by transition metal salts

The polymerization of N-vinylcarbazole (NVC) in the presence of transition metal salts such as WCI6, MoCI5, TaCl5 and NbCl5 under different reaction conditions was studied. In general, aromatic solvents were found to be superior to aliphatic solvents in the polymerization of NVC, i. e., both conversion and molecular weight were higher in aromatic solvents. It was observed that the polymerization reaction proceeds rapidly and almost quantitatively, even at low monomer concentration (< 5 × 10−2M) and at low catalyst to monomer mole ratio (10−5) in aromatic solvents. The copolymerization of NVC with acenaphthylene (ACN) was also investigated in solution at room temperature. The resulting homo- and copolymer were characterized by IR, NMR, x-ray diffraction, and elemental analysis. Thermal and photophysical properties are also reported. From the spectral data, the polymerization solvent was found to have a strong influence upon the polymer stereoregularity.