Synthesis And Characterization Of Liquid Crystalline Polymers Containing β-Cyclodextrin

It has attracted significant interest of research to construct artificial enzymes, molecule recognition sensors and other functional models utilizing the cone-shaped cyclodextrins, which process a hydrophobic cavity and a hydrophilic outside. As a multi-functional molecule, cyclodextrins was proved to be a useful auxiliary in agriculture, industry and pharmacy. Cyclodextrin polymers and liquid crystals have been studied and applied extensively in the field of the biomedical materials and in display materials. The combination with these two polymers possesses a potential application and will be play an important role in display materials, organic condctor materials and nonlinear optics fiedlds. The synthesis of liquid crystals(LCs) with new structures has become the fundamental task of molecular design in the advance of LC chemistry in recent years. In this paper, the liquid crystal cyclodextrin polymers were synthesized based on macromolecular design. The relationship between their molecular structure and physical properties was researched in detail.In order to obtain novel cyclodextrin polymers, two kinds of cyclodextrin-containing reactive monomers were synthesized. Monomers were first synthesized including carrying reactive group of Mono-[6-(2-acryl-oylaminoethy) amino]-20-acetyl-β-cyclodextrin (M1), 21-acryloyl-β-cyclodextrin(M2) and 21-[10-undecylen-1-yloxy]-β-cyclodextrin(M3), both of them carry cvinyl groups which can be polymerized with other functional monomers were also synthesized. In this dissertation, we will report the design and synthesis of four compounds of LCs and four corresponding series of LCPs. The four compounds of liquid crystals are 4-[4-(2-acryloyloxyethyloxy)benzoyloxy]-allyloxybenzoate(N1),4-[4-(2-undec-ylen-1-yloxy)benzoyloxy]-allyloxybenzoate (N2),4-[4-(2-acryloyloxyethyloxy)benzoyloxy]-biphenyl ester (N3),4-[4-(2-undecylen-1-yloxy) benzoyloxy]-biphenyl ester (N4). By grafting copolymerization ofβ-cyclodextrin monomers to the main chain of poly(hydrogenmethy-lsiloxane), two series of side-chain LCPs P1 and P2 are synthesized. P3 and P4 are synthesized by the synthesis ofβ-cyclodextrin ramifications and liquid crystals monomers using benzoyl peroxide as catalysts. To our knowledge, the obtained monomers and the polymers have never been reported up to now except M1.Their chemical structures were confirmed by FT-IR and their mesonmorphic phase behavior was investigated by differential scanning calorimetry(DSC), polarizing optical microscopy(POM). Their stucture-property relationships were discussed. The liquid crystalline monomer N1 is enantiotropic thermotropic LC. It displays threaded texture and schlieren texture on the heating and cooling cycles, and thus are nematic LC. The liquid crystalline monomer N2 is enantiotropic thermotropic LC. There is no texture on the heating cycle. On the cooling cycle, it displays drop let texture and schlieren texture, and thus are nematic LC. The liquid crystalline monomer N3 is enantiotropic thermotropic LC. It displays threaded texture and schlieren texture on the heating and cooling cycles, and thus are nematic LC. The liquid crystalline monomer N4 is enantiotropic thermotropic LC. it displays sector texture and cracked sector texture, and thus are smectic LC. The P1-P4 series of the novel LCPs are enantiotropic thermotropic LCs. P1 and P2 have the same main-chain polymethylhydrosiloxane. P3 and P4 series of star-shaped LCPs contain cyclode-xtrins. P3 series of star-shaped LCPs displays schlieren texture on the heating and cooling cycles. P4 series of star-shaped LCPs displays schlieren texture and drop let texture on the heating and cooling cycles. The P1-P4 series of the novel LCPs possess optical rotation because ofβ-cyclodextrins.