Synthesis and Thermal Properties of Poly(benzoxazole)s Based on Pendants

  • Jang, Hyewon (R&D Center, Kern Fine Materials Co.) ;
  • Lee, Seulbi (Dept. of Biochemical & Polymer Engineering, Chosun University) ;
  • Choi, Jae Kon (Dept. of Biochemical & Polymer Engineering, Chosun University)
  • Received : 2015.05.07
  • Accepted : 2015.05.15
  • Published : 2015.06.30


A series of wholly aromatic poly(hydroxyamide)s(PHAs), containing varying amounts of 2,6-dimethylphenoxy group and quinoxaline ring in the main chain, were synthesized by a direct polycondensation method. The inherent viscosities of the PHAs in either DMAc or DMAc/LiCl solution at $35^{\circ}C$ were found to be in the range of 1.02~1.90 dL/g. In the solubility study, we observed that PHA 1, PHA 2, and PHA 3 were dissolved in aprotic solvents such as DMAc, NMP, DMF, and DMSO with LiCl on heating; however, PHA 4, PHA 5, and PHA 6 could be dissolved in aprotic solvents on heating without LiCl. For poly(benzoxazole)s(PBOs), the 10% and maximum weight loss temperatures were in the range of $582{\sim}622^{\circ}C$ and $630{\sim}659^{\circ}C$, respectively. Residues of PBOs at $900^{\circ}C$ were found to be relatively high, which were in the range of 65.3~70.8%.


Supported by : 조선대학교


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  17. This work is based on the thesis submitted by HW Jang for MSc degree, Chosun University, Gwangju, Korea, 2015.