The Preparation Of Polymer Dispersed Liquid Crystal Film And Electro-optical Properties Research

Compared with the traditional display device,polymer dispersed liquid crystal PDLC is widely used,because it has simple preparation process and easy to produce large area flexible display,what’s more,high contrast and does not need the polarizer and other advantages. Polymer-dispersed liquid crystal PDLC is the pre-polymer mixed with the resin monomer and the low molecular weight liquid crystalline, in a certain time, the polymerization reaction occurs under certain conditions,than make liquid crystal in the form of micron-sized dispersed uniformly in the polymer network,liquid crystal dielectric anisotropy, so that the polymer dispersed liquid crystal film prepared in an energized state is transparent state and in the off state in the scattering state.The main application in the field of dimming glass, attenuators, modulators, holographic grating etc.It is currently a hot research topic LCD technologies.This paper focuses on the preparation of a high contrast, a low driving voltage, good properties of the polymer dispersed liquid crystal PDLC,we study from the choice of the monomer and resin,ratio of monomers and resins, preparation process and electro-optical properties.In the preparation of the PDLC,the morphology of PDLC were studied by scanning electron microscopy(SEM) and polarized optical microscopy pictures,than these data were compared and analyzed on the selection of raw materials and the ratio of the number of laws.By comparing the results of different experiments in the preparation of PDLC,we can selection of raw materials to obtain good performance, the composition ratio and experimental conditions.This experiment preparation of PDLC have some progress on the larger size,but under laboratory conditions of a relatively simple device,through a variety of ways to successfully prepared good electro-optic performance PDLC.The film thickness is uniform and the driving voltage is relatively low(approximately 20V).By UV polymerization phase separation(PIPS) prepared polymer dispersed liquid crystal(PDLC) film,it has a high scattering in the off state while in power with a high transmittance.Experiment by varying the kinds of monomer, resin and monomer ratio of the liquid crystal/pre-polymer composite system,to regulate the polymer and the liquid crystal droplet interface anchoring energy,to improve the electro-optical properties of the PDLC.To study effects of different condition to PDLC films under the polarizing microscope. Finally,optimization of process parameters,preparation of PDLC film with low threshold,high contrast.The experimental results show that using the mixed monomer lauryl methacrylate(LM) and Butyl acrylate(BA),and polyester resin 1350 prepolymer mixed with liquid crystal,after light curing phase separation membranes prepared PDLC,make it in the power-off state to have a high scattering property at a high transmission in the power-on,help to reduce the driving voltage and increase contrast.