Elastomers and Composites

The Rubber Society of Korea (한국고무학회)
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Synthesis and Properties of Semi-Flexible Aromatic Polyesters Containing Pentamethylene Group in Main Chain

주사슬에 펜타메틸렌기를 가지고 있는 반 유연성 방향족 폴리에스터의 합성 및 성질

  • 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)
  • 방문수 (공주대학교 신소재공학부) ;
  • 윤두수 (조선이공대학 생명환경화공과) ;
  • 최재곤 (조선대학교 응용화학소재공학과)
  • Published : 2009.12.31
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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.

주사슬에 방향족 고리와 펜타메틸렌 그룹을 포함하고 있는 반유연성 폴리에스터가 direct polycondensation 에 의하여 합성되었다. 합성된 중합체의 구조는 $^1H$-NMR과 FT-IR에 의해, 상전이거동에 대해서는 DSC, TGA 및 직교된 편광현미경에 의하여 관찰되었다. 합성된 중합체의 고유점성도 ($\eta_{inh}$)는 0.46에서 1.30 dL/g 사이의 값으로 측정되었고, 분자사슬 중 강직사슬그룹의 선형성이 클수록 용융전이온도 ($T_m$)는 높았으며, 용해도 조사에 사용된 유기용매에 대한 용해도는 감소되었다. 그리고, 중합체들 중 P-H, P-mH, P-4H는 넓은 비등방성 영역에서 열방성 네마틱 액정상을 나타내었으나 P-R, P-C, P-2B는 액정상을 나타내지 않았다.

Keywords

References

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