Photochemistry of Some Liquid Crystalline Stilbene Polyesters

The photochemical behavior of thin films and solutions of main chain nematic liquid crystalline trans-stilbene dicarboxylate polyesters (SDA) is discussed. Observation of spectral differences between solutions and thin films indicates the presence of chromophore aggregation. Hypochromic effects attributed to aggregation of chromophores become more pronounced upon thermal annealing above 40 degree(s) C. Polymer solutions and thin films (above 40 degree(s) C) exhibit the ability to undergo a reversible photocycloaddition reaction