Synthesis And Self - Assembly Structure Of Liquid Crystalline Compounds Of 4,6 - Diamino - 1,3,5 - Triazine Rod - Like

In recent years, as a high-tech materials, the synthesis and self-assembly of liquid crystalline compounds become a hot research subject. With the development of liquid crystalline compounds with novel structures, the understanding of the the self-assembly of liquid crystalline compounds are becoming better. How to get new types of liquid Crystalline, how to use reasonable driving force in order to design new liquid crystalline presenting novel liquid crystalline phases through changing the functional groups and making each organic combination of structure units on the basis of different topologies, are becoming a major research topic in liquid crystalline chemistry.In this thesis, rod-like dendritic liquid cystalline compounds based on4,6-diamino-1,3,5-triazine units (3C14-0T-T,6Cn-T-T and3Cn-2T-T) were designed and synthesized. Their self-assembly behavior were studied by POM DSC and XRD, and self-assembly models were builded by3Dmax program. As a strong non-covalent, the intermolecular hydrogen bondings in these compounds drive such rod-like dendritic molecular to self-assemble into different mesophases:3C14-0T-T self-assembles into Pm3n Cubic phase;6C12-T-T self-assembles into Im3m Cubic phase;6C14-T-T self-assembles into Im3m Cubic phase at low temperature stage and Pm3n Cubic phase at high temperature stage;3C12-2T-T self-assembles into Hexagonal Columnar phase;3C16-2T-T self-assembles into Columnar phase.The initial relationship between the different Cubic phase structures and the molecular structures of such rod-like dendritic liquid crystalline compounds containing4,6-diamino-1,3,5-triazine units have been discussed and established. Most interesting, compound6C14-T-T represents Im3m phase at the lower temperature stage and Pm3n Cubic phase at high temperature stage which is a converse phase sequence as reported in all literatures. This study result should contribute to prepare the different Cubic structures in a controlled manner and provide a fundamental knowledge for our further research work in the complex3D structures.