LIQUID CRYSTALLINE POLYMERS: 10: SYNTHESIS AND THERMAL BEHAVIOR OF SOME POLYETHERS CONTAINING A HEXAMETHYLENIC SPACER

The paper presents the synthesis and thermal behavior of some copolyethers containing a hexamethylenic spacer. The polymers were obtained using a phase transfer catalysis technique, starting from 1,6-dichlorohexane and various bisphenols as follows: 4,4′-dihydroxyazobenzene (DHAB), 4,4′-dihydroxydiphenyl (DHD), bisphenol A (BPA), 2,7-dihydroxynaphtyl (DN) and 4-hydroxydiphenyl sulfide (BPS). The synthesized polyethers have low molecular weights, being situated in the oligomeric domain. The polymers were characterized by 1H-NMR spectroscopy, DSC calorimetry and optical microscopy in polarized light. Only the polyethers containing DHAB, DHD and BPA units exhibited liquid crystalline phase. All liquid crystalline oligomers evidenced enantiotropic behavior.