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http://dx.doi.org/10.14478/ace.2017.1006

Synthesis and Properties of Hyperbranched Liquid Crystalline Polyesters by Direct Polycondensation  

Park, Jong-Ryul (Division of Advanced Materials Science and Engineering, Kongju National University,)
Kim, Hye-Mi (Division of Advanced Materials Science and Engineering, Kongju National University,)
Yoon, Doo-Soo (Department of Bioenvironmental & Chemical Engineering, Chosun College of Science & Technology)
Sohn, Jeong Sun (College of General Education Division of Undeclared Majors, Chosun University)
Bang, Moon-Soo (Division of Advanced Materials Science and Engineering, Kongju National University,)
Publication Information
Applied Chemistry for Engineering / v.28, no.2, 2017 , pp. 237-244 More about this Journal
Abstract
Hyperbranched liquid crystalline polymers with azomesogenic and cholesteryl groups in their terminal positions were designed and synthesized by direct polycondensation reaction. The chemical structures and thermal and mesomorphic properties of the synthesized polymers were investigated by FT-IR, $^1H-NMR$, differential scanning calorimetry (DSC), thermogravimetry analysis (TGA), and polarizing optical microscopy (POM). The inherent viscosities (${\eta}_{inh}$) of the polymers were measured to be between 0.30 and 0.50 dL/g in phenol/p-chlorophenol/1,1,2,2-tetrachloroethane (25/40/35 = w/w/w). The degree of branching (DB) in these polymers ranged from 0.37 to 0.75; they, as amorphous polymer, showed glass transition temperatures ranging from 80 to $120^{\circ}C$; the polymers readily dissolved in most of the organic solvents used in the experiments. Only hyperbranched polymers with a cholesteryl group as their mesogenic group showed liquid crystalline phases.
Keywords
azobenzene; cholesteryl; direct polycondensation; hyperbranch; liquid crystalline polymers;
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Times Cited By KSCI : 3  (Citation Analysis)
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