| Two kinds of liquid crystalline polymers with azobenzene mesogen based on mesogen-jacketed liquid crystalline polymer and dendronized polymer were designed and successfully synthesized, and the effects of the length of flexible spacers, the generation of dendrons and the molecular weight on the phase structures and phase behaviors of polymers were investigated.(1) The MCSCLCPs based on MJLCPs with azobenzene LC mesogens, poly (2, 5-bis{[6-(4-methoxy-4′-oxy azobenzene) alkyl] oxycarbonyl}styrene) (B1~B5, n=4; C1~C5, n=2.) were successfully synthesized via ATRP. The polymers B1~B5 exhibited the similar phase behavior, i.e., the polymers exhibited hexiatic nematic phase at lower temperature, and the polymers exhibited nematic phase at middle temperature. However, the polymers C1~C5 didn't exhibit liquid crystalline property.(2) The first and second dendrionized polymers with poly (vinyl terephthalate) as the backbones and peripheral azobenzene mesogen functional dendrons as the side chain were synthesized via free radical polymerization, and the effects of generation of dendrons and molecular weight of polymer on the liquid crystalline behaviors of the dendronized polymers were investigated. The experiment results revealed that for the first generation dendronized polymer (PDABCS), the low molecular weight polymer (LMW-PDABCS) exhibited liquid crystalline behavior of the conventional side-chain liquid crystalline polymer with azobenzene mesogen and only showed a liquid crystal phase transition, and the high molecular weight polymer (HMW-PDABCS) exhibited complicated combined supermolecular structure. For the second generation dendronized polymer (PDDABCS), we could not obtain the high molecular weight materials because the bulky dendritic fragments inhibit the formation of polymers completely and the low...
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