Elastomers and Composites

The Rubber Society of Korea (한국고무학회)
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Synthesis and Properties of Side Chain Liquid Crystalline Polymers with Siloxane Flexible Chain

  • Park, Jong-Ryul (Division of Advanced Materials Science and Engineering, Kongju National University) ;
  • Bang, Moon-Soo (Division of Advanced Materials Science and Engineering, Kongju National University) ;
  • Choi, Jae-Kon (Deptartment of Biochemical & Polymer Engineering, Chosun University)
  • Received : 2017.07.24
  • Accepted : 2017.07.31
  • Published : 2017.09.30
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Abstract

Side-chain liquid crystalline polymers having polysiloxane skeletons were synthesized by a thiol-ene reaction, using two kinds of mesogenic groups: a cholesteryl group for induction into a cholesteric liquid crystal phase and a triazomesogenic group for imparting light-sensitivity. All the synthesized polymers were crystalline, except the one with a single cholesteryl group. Crystallinity, glass transition temperature, and melt transition temperature increased with increasing content of the azomesogenic group. The polymer (P-C10A0) with a single cholesteryl group has a cholesteric phase, the one (P-C0A10) with a single azomesogenic group has a smectic phase, and those with both types of mesogenic groups showed both smectic and cholesteric phases. The temperature ranges of the two liquid crystalline phases in the co-polymers were independent of the contents of the two types of mesogenic groups. The rate of photoisomerization of the light-sensitive azobenzene group in the polymer decreased with increasing azobenzene content due to steric hindrance between the azomesogenic groups.

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References

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  21. This work is based on the thesis submitted by J. R. Park for M. Eng. degree, Kongju University, Cheonan, Korea, 2016.