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The synthesis of a novel optically active methacrylic monomer containing in the side chain the S3hydroxyNphenyl pyrrolidine ring linked to a 4cyanophenylazocarbazole moiety SMCAPPC and of the analogous achiral monomer MCAPEC is described. Both the monomers have been radically polymerized to produce the corresponding homopolymers as well as the copolymer at 50 molar composition. The photoinduction of birefringence has been assessed on thin films of the polymeric materials in order to evaluate their behavior as materials for optical data storage. Surface relief gratings SRG can also be inscribed over the material. The results are interpreted in terms of different cooperative performance and conformational stiffness of the chromophoric counits in the polymeric derivatives.

A novel opticallyactive polymeric methacrylate, bearing the S3hydroxy pyrrolidinyl group linked through the nitrogen atom to an azopyridine chromophore, was synthesized and investigated in combination with a polymeric methacrylate incorporating the photoisomerizable spiropyran chromophore in the sidechain. In the presence of acid, this system can be operated in solution to modulate the protonation of the azopyridine moieties by photoisomerizing the spiropyran component. In addition to UVvis spectroscopy, the proton transfer process occurring between the macromolecular components can be also followed by CD spectroscopy, thus behaving as a chiroptical switch.

The synthesis of novel optically active monomers, namely (S)-(+)- and (R)-(–)-2-methacryloyloxy-N-(4-azobenzene)succinimide and (S)-(+)-2-methacryloyloxy-N-(4'-nitro-4-azobenzene)succinimide, is described. The monomers have been radically polymerized to afford the corresponding optically active homopolymers, characterized by the presence of an optically active rigid succinimide ring in the side chain linked to the trans-azoaromatic system through the imide nitrogen atom. A series of copolymers containing both the enantiomeric monomers in different molar amounts, have also been prepared in order to observe possible effects on the optical activity of the resulting derivatives. The chiroptical and conformational properties of the polymers in solution have been investigated by circular dichroism measurements and compared with those of low molecular weight model compounds, purposely synthesized, with the aim to verify the existence of cooperative interactions between chromophoric groups disposed along the macromolecular chain according to dissymmetric conformations.

The synthesis of a novel optically active monomer containing a photochromic chromophore, trans-(S)-4-(2-methacryloyloxypropanoyloxy)-4´-formylazobenzene, is described. The monomer was radically homopolymerized and copolymerized with methyl methacrylate to afford the corresponding optically active polymers, which were fully characterized. The chirooptical and conformational properties in solution of the resulting polymers were investigated by circular dichroism and solvatochromism measurements and compared with those of the corresponding low molecular weight model compound, trans-(S)-4-(2-pivaloyloxypropanoyloxy)-4´-formylazobenzene, purposely synthesized.