Static Permittivity and Electro-Optical Properties of Bi-Component Orthoconic Antiferroelectric Liquid Crystalline Mixtures Targeted for Polymer Stabilized Sensing Systems

Polymers

Madhumita Das Sarkar¹  Banani Das²  Shantiram Nepal²  Malay Kumar Das³  Magdalena Urbańska⁴  Michał Czerwiński⁴ 

[1] Department of Microelectronics and VLSI Technology, Maulana Abul Kalam Azad University of Technology, WB, Kolkata 741249, India;Department of Physics, Siliguri Institute of Technology, Siliguri 734009, India;Department of Physics, University of North Bengal, Siliguri 734013, India;Faculty of Advanced Technologies and Chemistry, Military University of Technology, 00-908 Warsaw, Poland;

关键词: antiferroelectric liquid crystals;    polymer stabilization;    permittivity;    spontaneous polarization;    response time;    rotational viscosity;   

DOI  :  10.3390/polym14050956

来源: DOAJ

【 摘 要 】

The behavior of two newly formulated bi-component orthoconic antiferroelectric liquid crystalline (OAFLC) systems, i.e., the Compound A + Compound B mixture system and Compound C + Compound B mixture system has been discussed in light of temperature and concentration dependencies of helical pitch length, spontaneous polarization, relaxation time, bulk viscosity, and the anchoring energy strength coefficient, together with static dielectric permittivity (ε) and dielectric anisotropy. Compound A + Compound B mixtures possess spontaneous polarization between 190–340 nC.cm⁻² and fast relaxation times between 190–320 µs in the smectic antiferroelectric SmC_A* phase at room temperature. Compound C + Compound B mixtures also have a spontaneous polarization in the range of 190–280 nC.cm⁻² and relaxation times in the range of 190–230 µs at room temperature. Most of the mixtures have a helical pitch below one micrometer in the SmC_A* phase. These advanced mixtures show a broad temperature range of the antiferroelectric SmC_A* phase, fast switching of molecules under an applied electric field, negative dielectric anisotropy and a short helical pitch, confirming the advantage of designing new polymer-stabilized OAFLC that is targeted for novel application in sensing devices, utilizing the fast responsive electro-optical modulation elements.

【 授权许可】

Unknown