Research Into Effect Of Polymerization Process And Doping On Electro-optic Property Of Polymer-stabilized Blue Phase Liquid Crystal

Blue phase liquid crystal, with a three-dimensional structureconsisting of double twisted cylinder structure, exists in a very narrowtemperature range between the chiral nematic phase and the isotropicphase. Blue phase liquid crystal exhibits some attractive features includingoptical isotropic status in the absence of electric field, self-assembled cubicstructures, Bragg reflection of light in visible wavelength, andsub-millisecond response time. Although the unique features of bluephases are very attractive, the temperature range at which they areavailable is only on the order of1K, which prohibits consideration withregard to potential applications. Since the temperature range broadened tomore than60K by stabilizing the disclination lines with polymer network,blue phase liquid crystal has attracted people s interest for its greatpotential application in field sequential displays, phase modulator devices,and photonic crystals.However, some critical issues, such as high driving voltage, hysteresis,residual birefringence, and weak thermal stability must be solved beforethey can be widely applied. In this paper, different concentrations of chiraldopant, polymer network, and temperature effect are investigated toimprove the electro-optic properties of polymer-stabilized blue phaseliquid crystals and analyze the mechanism that affect the electro-opticproperties of polymer-stabilized blue phase liquid crystal s device. It offersthe guidance for the adjustment of chemical composition of blue phase liquid crystal mixtures and provides the foundation of the research intoeffect of polymerization process and doping on the electro-optic propertiesof polymer-stabilized blue phase liquid crystal. To study thepolymerization process of the blue phase liquid crystal, a criticaltemperature is found in the phase transition, which affects the electro-opticproperties and polymer stabilization of polymer-stabilized blue phaseliquid crystals. The lattice formation process is elaborated according to thecrystal nucleus growth process in crystallography. Then a small amount ofpolyaniline-functionalized graphene nanosheets is doped into conventionalpolymer-stabilized blue phase liquid crystal, and the electro-optic propertyeffects are studied systematically. The driving capability of blue phaseliquid crystal can be much improved in that the Kerr constant of blue phaseliquid crystal doped with0.05wt%polyaniline-functionalized graphene isincreased by about55%, and response time, hysteresis and residualbirefringence have no degradation compared with that of blue phase liquidcrystal without polyaniline-functionalized graphene.