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Synthesis and Properties of Semi-Flexible Aromatic Polyesters Containing Pentamethylene Group in Main Chain  

Bang, Moon-Soo (Division of Advanced Materials Engineering, Kongju National University)
Yoon, Doo-Soo (Dept. of Bioenvironmental & Chemical Engineering, Chosun College University of Science & Technology)
Choi, Jae-Kon (Dept. of Polymer Science & Engineering, Chosun University)
Publication Information
Elastomers and Composites / v.44, no.4, 2009 , pp. 436-441 More about this Journal
Abstract
Semi flexible polyesters containing aromatic rings and pentamethylene groups in the main chain were synthesized by direct polycondensation reaction. The structures of these polymers were investigated by $^1H$-NMR and FT-IR and the phase transition behavior was characterized with DSC, TGA and crossed polarizing microscope. Inherent viscosities ($\eta_{inh}$) of polymers measured in phenol/p-chlorophenol/1,1,2,2-tetrachloroethane were between 0.46 and 1.30 dL/g. As increasing the linearlity of rigid moieties in polyster, melting transition temperatures ($T_m$) increased and solubilities in organic solvents decreased. P-H, P-mH and P-4H of the polymers formed turbid melts that showed stir-opalescence and nematic phase at the broad anisotropic region, However, P-R, P-C and P-2B did not exhibit any textures related to the liquid crystallinity.
Keywords
liquid crystal; polyester; mesogen; methylene spacer; direct polycondensation;
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Times Cited By KSCI : 1  (Citation Analysis)
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