| Summary: | 碩士 === 國立交通大學 === 應用化學系 === 87 === The goal of this research is mainly focused on the synthesis of side-chain liquid crystalline polymers containing thiophene-based mesogens.Four series of new side-chain liquid crystalline polymers will be prepared according to carefully molecular design of polymer backbone,spacer,mesogen and end group.Polysiloxane is used as the polymer backbone.Three to eleven methylene units are used as flexible spacer. Thiophenyl benzoate and Thiophenyl 4-hydroxybiphenyl-4￠-carboxylate are designed for the mesogen,and a cyano and a methoxy are designed for the end groups.the prepared liquid crystal monomers are grafted onto the polysiloxane backbone via hydrosilation reaction.The obtained monomers and polymers are characterized by FT-IR,NMR and determined by DSC and optical polarizing microscope. In the first and second series of monomers and polymers which contain two rings do not present any mesophase.In the Third series which contain three aromatic rings and the cyano end group presnet respectively a smectic A phase and a nematic phase.The fourth series just present a nematic phase.The synthesized liquid crystalline polymers have potential applications in the field of stationary phase of column chromatography
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