A postfunctionalization strategy to develop carbazole-based photorefractive polymers with low Tg

Carbazole-based polymers bearing methine groups with low glass transition temperature (Tg) for photorefractive purpose were prepared via postfunctionalization strategy. The successful reaction was identified by spectroscopic analysis and gel permeation chromatography. This approach is more facile compared with the direct polymerization from corresponding functional monomer. Chromophore content of the resulting polymers varied from 25% to 63% depending on the type of chromophore as calculated from 1H NMR spectra. Molecular weight of the polymers are higher than 2.4 × 105, and the polymers are easily soluble in common organic solvents like DMF and THF. Tg of the polymers ranges from 40 to 58 °C depending on the structure of chromophore, and the polymers are relatively stable under 310 °C.