SYNTHESIS OF POLY VINYL ETHERS WITH PENDANT NONLINEAR OPTICAL AZO DYES

Two vinyl ether polymers with pendant 4'-amino-4-nitroazobenzene dyes were synthesized with different lengths of spacer from the main chain. The synthesis involved polymerization of 2-chloroethylvinyl ether with HI/I2 to give a polymer of M(n) 13200 and M(w)/M(n) 1.23. The azo-dye molecules were attached to this polymer backbone by a Williamson ether synthesis route using a propyl or hexyl alcohol derivative of the azo dye. High loading of the dyes (> 75%) was achieved as measured by visible spectrophotometry, elemental analysis and H-1-NMR. The polymers exhibit high solubility in a range of solvents and thermal stability up to 200-degrees in air. Liquid crystal (nematic) behaviour is observed for these polymers on cooling from the isotropic melt phase.