Hysteresis-free polymer-stabilised blue phase liquid crystals comprising low surface tension monomers

Abstract

Partial replacement of fluoroacrylates in the monomer composition is able to reduce the free energy of polymer-stabilised blue phase liquid crystal (PSBPLC) due to their low surface tension. The ease of blue phase platelet texture formation is observed under fast cooling and short annealing time before ultraviolet irradiation. The peak driving voltages are dramatically decreased from 9% to 16% in the resulting PSBPLCs. In addition, the hysteresis is completely suppressed in the PSBPLC containing 3FM-M1. The other PSBPLC containing fluoroacrylates retain very small hysteresis (oV<0.8V) regardless the fluorine atom numbers. In comparison with current PSBPLCs, the fluoroacrylates serve as mesophase enhancer not only to promote the blue phase formation but also to improve the electro-optical properties.