Design,Synthesis And Liquid Crystalline Behavior Of Side Chain Liquid Crystalline Polymers With Hierarchical Ordered Structure

Hierarchical ordered structure can take the performances of different scales into whole of organism which to satisfied the demand for multifunctional materials. It has potential application value in the field of bionic materials,The construct of hierarchical ordered structure was mainly by changing the block copolymer composition and structure at present, which almost were nanometer size. There were a small number of references about subnanometer size(less than 10 nm), thus, constructing of non-block copolymers hierarchical ordered structure with subnanometer size has theoretical significance. In this paper, we have designed and synthesized a series of side chain liquid crystalline polymers with biphenyl or azobenzene mesogenic units, and discussed the causes of hierarchical ordered structure was formed. The main topics of this paper were as follows:1. Design two types of side chain liquid crystal polymer: a series of SCLCPs based on acrylate main-chain, ploy 4, 4'-alkoxybiphenylyl acrylate P(M)Bi C6, and another a series of SCLCPs based on acrylate main-chain, were successfully synthesized by free radical polymerization, ploy 4'-((4-((4-(alkoxyphenyl)biphenylylo xy)-[1,1'-biphenyl]-4-yl acrylate(PBi6BiC6 PMBi6BiC6 and PMBi10BiC6)were designed and successfully synthesized via free radical polymerization. The phase structures and transitions of the polymers were investigated by the combination of techniques including DSC, POM and 1D WAXD. The experimental results revealed that PMBiC6 and PBiC6 can form multiple-lengths scales smectic phase, but were not hierarchical ordered structure. By constrast, P(M)BimBiC6(m=6,10) can form single scale smectic phase. Side chain formed smectic phase A, and the biphenyl mesogenic units connected with the tail chain also ordered arrangement form of advanced orderly structure. After raised temperature, side chain activity increased, the order of biphenyl mesogenic unit with the tail chain was broken, and the side chain can still maintain orderly structure. Once again raised the temperature led to orderly structure disappeared, entered sotropy. Therefore, with effect of temperature P(M)BimBiC6(m=6,10) can form including side chain to construct the subnanoscale ordered structure and the structures of biphenyl mesogenic units constructing in two different scales with hierarchical ordered structure of SCLCPs.2. Design two types of side chain liquid crystal polymer: a series of SCLCPs based on the azobenzene mesogen which were directly attached to the polymer backbone without the flexible spacer, poly 4, 4'-alkoxy azobenzeneyl acrylate(PMAzoC6) and another a series of SCLCPs based on acrylate main-chain, were successfully synthesized by free radical polymerization, poly 4'-((4-((4-(alkoxyphenyl)diazenyl)phenoxy)decyl)oxy)-[1,1'-biphenyl]-4-yl acrylate(PBi6AzoC6, PMBi6AzoC6 and PMBi10AzoC6) were in and successfully synthesized via free radical polymerization. The phase structures and transitions of the polymers were investigated by the combination of techniques including DSC, POM and 1D WAXD. The experimental results revealed that PMAzoC6 can form single scale smectic phase A, the same main chain of side chain mesogenic units tend to be arranged parallel to each other in scales, forming much subnanoscale structure. At the same time, there are orderly arranged between each other in single scale, forming advanced orderly structure. By constrast, P(M)BimAzoC6(m=6,10) can form single scale smectic phase. Side chain formed orderly in smectic phase A, and the azobenzene mesogenic units connected with the tail chain also ordered arrangement form of advanced orderly structure. After raised temperature, side chain activity increased, the order of azobenzene mesogenic units with the tail chain was broken, and the side chain can still maintain orderly structure. Once again raised the temperature led to orderly structure disappeared, entered sotropy. Therefore, with effect of temperature P(M)Bim AzoC6(m=6,10) can form including side chain to construct the subnanoscale ordered structure and the structures of azobenzene mesogenic units constructing in two different scales with hierarchical ordered structure of SCLCPs.