Synthesis and characterization of side-chain maleimide-styrene copolymers with new pendant azobenzene moieties

摘要

Four side-chain maleimide-styrene polymers have been synthesized from maleimide-alt-styrene copolymer (MASt) and some original azo-moieties using polymer analogous reactions. The structures have been obtained with good yields; remarkably, they showed a high chromophore load, up to ～100%. The polymers were characterized by means of SEC, FT-IR, 1H-NMR, DSC-TGA, and elemental analysis. The side-chain polymers exhibited improved solubility and enhanced thermal stability up to 320°C, while their glass transition temperatures have been found to be as high as 210°C. The third-order NLO refraction (n_2) and susceptibility Χ~((3)) coefficients were measured by Z-scan technique. The results of Z-scan measurements showed that the polymers have only nonlinear refraction, the nonlinear absorption being negligible.