Pinning Effect of Mixed Cellulose Ester Membrane on Appearance of Cholesteric Blue Phases

Abstract

Temperature range of cholesteric blue phase I (BP I) was expanded by infiltrating liquid crystal (LC) that exhibits BP I and BP II into a mixed cellulose ester membrane (MCEM). Cooling rate dependence of the BP I temperature range was investigated, which indicated that the expansion of BP temperature range upon infiltrating LC into MCEM was induced by the pinning effect at network surfaces in the MCEM. In particular, the temperature range of BP I infiltrated in 0.2-µm MCEM is eight times wider than that of pure BP LC compound. Pore size dependence of expansions was also investigated.