Preparation And Properties Of Circularly Polarized Luminescent Blue Phase Liquid Crystal Elastomer

Circularly polarized luminescence（CPL）materials have drawn considerable attention from researchers due to their potential applications in fields such as asymmetric catalysis,3D displays,information storage,and encryption.However,the luminescence dissymmetry factor(g_lum),which is the most crucial CPL parameter,has yet to be optimized satisfactorily.Consequently,there is a pressing and fundamental challenge in the CPL research field to obtain large g_lum values.Chiral liquid crystals possess chiral structures that selectively reflect left-or right-handed circularly polarized light.Combing chiral liquid crystals as a template with luminescent nanomaterials can effectively enhance the g_lum values of the luminescent nanomaterials.Additionally,the stimulus-responsive properties of the chiral liquid crystals template offer significant advantages in achieving dynamic control of CPL signals.Blue phase liquid crystals（BPLC）are promising candidates for the construction of CPL active materials due to their self-assembled three-dimensional soft photonic structure,high chirality,and external field regulation properties.However,there has been limited research on CPL active materials based on BPLC.By combining blue phase liquid crystal elastomers（BPLCE）containing disulfide bonds with quantum dots,this paper presents the preparation of CPL-BPLCE.The stimulus-response behavior and factors affecting CPL were investigated to explore potential applications in information storage and encryption.The main research contents encompass:1.Preparation and study of BPLCE containing dynamic disulfide bonds.The preparation and study of BPLCE were systematically investigated by studying the effects of disulfide bond chain extenders,liquid crystal monomer ratios,and thiol chain extenders on BPLCE.By adjusting the proportions of each component,BPLCE with excellent thermal performance,good chemical resistance,and high elasticity were successfully prepared.Under mechanical force induction,the lattice structure of BPLCE underwent reversible changes that shifted the photonic bandgap from 625 nm to 465 nm.Furthermore,dynamic disulfide bonds allowed for the reconstruction and welding of BPLCE shapes.2.Preparation and CPL performance study of CPL-BPLCE.Quantum dots were introduced into BPLCE to successfully prepare CPL-BPLCE,achieving full-color circularly polarized luminescence by doping quantum dots with different fluorescent colors,with a|g_lum|value as high as0.74.The generation of CPL signals in the system was induced by the chiral environment of CPL-BPLCE and was independent of the photonic bandgap.Therefore,even without matching reflection bands or fluorescence emission bands,a larger g_lum value could be obtained.By inducing changes in the lattice structure of CPL-BPLCE through mechanical force stimulation,dynamic control over the presence or absence of CPL was achieved.Furthermore,this change could be fixed using dynamic disulfide bonds present in the system.BPLCE with dynamically tunable CPL is developed,and the material has broad application scenarios in the fields of stimulus response,information storage,and information encryption.