WHOLLY AROMATIC POLYESTERS CONTAINING NLO CHROMOPHORES IN THE SIDE-CHAIN

A series of poly(1,4-phenylene terephthalates) with pendant NLO chromo phores was prepared by the solution polycondensation of 2,5-NLO chromo phore substituted terephthalic acid with hydroquinone. The polymers ob tained gave satisfactory NMR and elemental analysis results when takin g into account their expected structures and the inherent viscosity va lue proved the polymeric character of all polymers. DSC, optical polar izing microscopy and WAXS studies revealed that none of these polymers exhibited liquid crystalline mesophases. Preliminary results on NLO p roperties of these polymers showed a surprisingly large second harmoni c signal relative to a Y-cut quartz plate.