Infrared Microspectroscopic Investigation of the Diffusion of E7 into PiBMA

Abstract

The components of a liquid crystal mixture (E7) have been shown to diffuse at different rates in Polymer Dispersed Liquid Crystals (PDLCs). It was observed in this work that liquid crystals of different molecular weights diffuse into poly(isobutyl methacrylate) (PiBMA) at different rates at a constant temperature. It was also determined that the components in a liquid crystal mixture diffuse into the polymer at different rates. The effect is quite small under normal conditions, so elevated temperatures, simplified diffusion boundaries and extended time scales were employed to magnify the diffusion separation effects for study. Although this work demonstrates that these components diffuse at different rates, the short phase separation times experienced during the generation of a PDLC are probably insufficient to promote this effect to the point where optical properties are adversely affected.