SYNTHESIS AND POLYMERIZATION OF LIQUID-CRYSTALLINE MONOMERS HAVING DIENE GROUPS

Biphenyl compounds having diene groups were synthesized. In the first class of compounds, the diene groups were directly attached to one end or both ends of the biphenyl through ester bonding. In the second class of compounds, the diene groups were attached to one end or both ends of the biphenyl through methylene spacers. Only the first class of compounds were found to show a liquid-crystalline phase. The bulk thermal and photopolymerizations of the first class of compounds were carried out in the crystalline phase, liquid-crystalline phase and isotropic phase. It was found that the morphology of the systems strongly affected the polymerization rate and conversion. The polymerization behaviour is discussed in relation to the morphology of the system.