Synthesis and Liquid Crystalline Properties of Hyperbranched Aromatic Polyesters Consisting of Azoxybenzene Mesogens and Polymethylene Spacers

Bulletin of the Korean chemical society

Jung-Il Jin¹  Jun-Woo Lee¹  Young Suk Park¹ 

关键词: Hyperbranched LCPs;    Aromatic polyesters;    Built-in mesogen;    Degree of branching;   

DOI  :  

学科分类：化学（综合）

来源: Korean Chemical Society

【 摘 要 】

A new series of hyperbranched aromatic polyesters containing azoxybenzene mesogens and polymethylene spacers were prepared by polymerizing AB2 type monomers that have the isophthaloyl dicarboxylic acid terminal at one end and the p-oxyphenol terminal at the other end. The monomers contain a built-in azoxybenzene mesogen that is linked to the terminal groups through polymethylene spacers. The polyesters prepared were characterized by solution viscosity, differential scanning calorimetry, X-ray diffractometry and polarizing microscopy. All of the polyesters were found to be thermotropic (nematic). Their glass-transition temperatures and mesophase temperature ranges were very sensitive to the length of the two spacers existing in the repeating unit. The degree of branching of one of the polyesters was determined by the NMR spectroscopy and found to be 0.56.

【 授权许可】

Unknown