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http://dx.doi.org/10.7473/EC.2013.48.4.306

Synthesis and Properties of Semi-flexible Liquid Crystalline Polyesters with Rigid Lateral Group  

Park, Jong-Ryul (Division of Advanced Materials Science and Engineering, Kongju National University)
Lee, Eung-Jae (Dept. of Bioenvironmental & Chemical Engineering, Chosun College University of Science & Technology)
Yoon, Doo-Soo (Dept. of Bioenvironmental & Chemical Engineering, Chosun College University of Science & Technology)
Bang, Moon-Soo (Division of Advanced Materials Science and Engineering, Kongju National University)
Choi, Jae-Kon (Dept. of Biochemical & Polymer Engineering, Chosun University)
Publication Information
Elastomers and Composites / v.48, no.4, 2013 , pp. 306-311 More about this Journal
Abstract
A series of liquid crystalline polyesters containing the 4-chloro benzoate group on the hydroquinone unit of rigid group were synthesized through solution polymerization of 2,5-di(4-chlorobenzoate)hydroquinones and 4,4'-dicarboxy-${\alpha},{\omega}$-diphenoxy alkane. The structure and properties for synthesized polymers were investigated by $^1H$-NMR, FT-IR, DSC, TGA, and POM. As result of investigations, The presence of the methylene group and bulky lateral groups in polymer chain have a great influence on the properties of polymers such as solubilities and thermal transitions. The optical textures of polymers revealed a weak birefringence in the melt and indicated that they form nematic mesophase. All polymers have very narrow mesophase temperature ranges.
Keywords
liquid crystalline polyester; x-shaped rigid group; mesogenic unit; methylene spacer;
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