Development of novel sulfur-containing liquid crystalline polymers and their application to various polarizing films

2018 Fiscal Year Final Research Report

• Project/Area Number: 17K14493
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Polymer chemistry
• Research Institution: Toyohashi University of Technology
• Principal Investigator: Arakawa Yuki 豊橋技術科学大学, 工学(系)研究科(研究院), 助教 (30757365)
• Project Period (FY): 2017-04-01 – 2019-03-31
• Keywords: 液晶性高分子 / 硫黄 / チオエーテル / 偏光材料 / 複屈折

Outline of Final Research Achievements

We developed new sulfur- or thioether-containing liquid crystalline polymers based on bisphenyl benzoates and bistolans that are representative mesogenic structures. At first, we designed polymers with such mesogenic structures in the sinde chains, and revealed that they form well-defined liquid crystal phases that are distinct compared with those for ether counterparts, due to sulfur attractive interaction. In addition, we synthesized a bifunctionalized photo-polymerizable thioether-containing liquid crystalline monomer, and successfully fablicated its uniaxially aligned film. In conmparison to the ether counterpart, it showed higher birefringence, promising its usefulness for high birefringence materials. Finally, polymers with thioether-containing bisphenyl benzoates in the main chains also synthesized. They formed liquid crystal phases, and were vitrified at ambient temperature, showing their potential for liquid crystal film applications.

Free Research Field

液晶化学

Academic Significance and Societal Importance of the Research Achievements

分極率の高いチオエーテルをリンカーとする液晶性高分子は、位相差フィルムなどへの応用を指向した高複屈折性材料に適した分子設計の一つであると考えられるものの、これまでに液晶性高分子における研究例は極めて少なく、それらの液晶性や光学特性は明らかになっていない。本研究では、様々な液晶分子構造をチオエーテル鎖で連結した側鎖型および主鎖型高分子を合成し、それらの相転移挙動、液晶相構造、および光学特性の評価を行った。従来の炭素や酸素系と比較して特異な液晶相構造を示すことや、優れた光学特性を有することが明らかとなった。