Journal of Polymer Science Part A: Polymer Chemistry, Vol.38, No.6, 988-998, 2000
New polymers with mesogens in the side chain and kinked aromatic structures in the main chain from the polyaddition of bis(epoxide)s and di(ester)s
Nine polymers with kinked aromatic structures in the main chain and biphenylene-type mesogenic groups in the side chain were synthesized by the polyaddition of bis(epoxide)s and thio- and O-esters. Tetrabutylphosphonium chloride and tetraphenylphosphonium chloride effectively catalyzed the polymerization. The thermal behavior of the polymers was measured by DSC and polarizing optical microscopy. The effect of annealing time on the degree of crystallization was investigated by DSC analysis. Polymers containing 100% of the kinked aromatic groups and 1,3-propylene glycol in the main chain were amorphous. However, when half of the main-chain aromatic moieties were composed of kinked groups and the other half of the aromatics were linear rodlike groups, the polymers were crystalline. The incorporation of kinked groups into the main chain of side-chain liquid-crystalline polymers suppressed the formation of liquid crystallinity. The polymer with mesogenic aromatic structures in both the main chain and the side chain was capable of for ming a liquid-crystalline phase.
Keywords:liquid-crystalline polymer;kinked structure;structure/property relation;side-chain liquid-crystalline polymer;polyaddition;polyether