Methacrylic polymers containing optically active side-chain carbazole: synthesis, characterization and photoconductive properties

Two novel optically active polymethacrylates bearing in the side chain a cyclic chiral group of one prevailing absolute configuration linked to the carbazole chromophore, deriving from the related monomers (S)-(-)-3-methacryloyloxy-N-[3-(9-ethylcarbazolyl)]pyrrolidine [(S)-(-)- MECP] and (S)-(+)-2-methacryloyloxy-N-[3-(9-ethylcarbazolyl)]succinimide [(S)-(+)-MECSI], have been prepared and characterized with the aim to obtain materials suitable to photoconductive applications. Poly[(S)-(-)-MECP] and poly[(S)-(+)-MECSI] exhibit remarkable thermal stability, with glass transition temperature around 200 °C and decomposition temperatures in the range 330–350 °C. Spectroscopic, thermal and chiroptical characterizations indicate the occurrence of dipolar interactions among the side chain moieties and the presence of chiral conformation at least for chain segments of the macromolecules. The photoconductive properties are discussed in terms of extent of conjugation in the side chain based on the electron-acceptor or electron-donor properties of the optically active ring linked to the carbazole group.