5CB Inorganic Nanoparticles / Composite Liquid Crystal Material Preparation And Performance

Liquid crystal with excellent electrooptical property is required accompanying with the development of liquid crystal display technology. Doping liquid crystal with nanoparticles is a simple and efficient method. In this paper, the effects of nanoparticles of ferroelectric BaTiO3, multiferroic BiFeO3and Ag on the electrooptical propery, viscosity and phase transition temperature of5CB liquid crystal were investigated. Firstly, the pure phase of nano BiFeO3, monodisperse BaTiO3(<10nm) and nano Ag was prepared with sol-gel self-propagating combustion method, hydro thermal sysnthesis method and thermal decomposition of Ag2C2O4, respectively. Then, the electrooptical parameters of5CB doped with BaTiO3, BiFeO3and Ag nanoparticles respectivily were measured. The results showed that these nanoparticles did not obviously improve the eletrooptical property of5CB. Based on the distribution of nanoparticles in5CB, it was thought that the nanoparticles agglomeration in5CB was the main reason. So, the possibility of nanoparticles even distribution in liquid crystal was studied by using nano Ag. The nano Ag/liquid crystal hybrid composite was obtained, in which nanoparticles existing by the means of monodispersed and no agglomeration was observed. This result proved that liquid crystal doped with nanoparticles by in-situ synthesis, was one of the efficient methods. The mechanism of nanoparticles growing and distribution in liquid crystal was discussed preliminary.