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Abstract
Investigation of precursors of thermotropic nematic polyesters with flexible spacers ((CH2)10 and (CH2)7) and mesogens in the main chain is reported. The mesogens are
Mixtures of structural isomers of 2,2′-dimethylazoxybenzene derivatives display broad multiple melting. Several types of sequencing of mesogen and spacer were investigated. Compounds formed by the sequence mesogen-central spacer-mesogen appear to provide an adequate model of polymeric behavior. Influence of mesogen and spacer on phase transition entropies and mesogen nematic order parameter, as well as temperature dependence of alkyl chain flexibility were investigated in selected compounds. These can also serve as models for study of mesophase glasses and the semicrystalline state of nematic polymers.
