Experimental Study of Gravitation Effects on Liquid Crystal Phase Transitions in Polydisperse Aqueous Suspensions of Mg Al-2 Layered Double Hydroxide

Effects of gravity on liquid crystal phase transitions (LCPT) in polydisperse aqueous suspensions of Mg Al-2 layered double hydroxide (LDHs) were studied under normal gravity condition. Samples with different suspension concentration (SC) were tested for 15 days and the relevant changes in samples were observed through crossed polarizers. Our results showed: (a) the samples were still isotropic (I) when SC 30 wt%, the suspensions were in a gel state, and the gel network slowed down the LCPT. The above different behavior of phase transitions is apparently due to the concentration gradient and fractionation caused by gravity. This study provides guidance on how to select samples of LDHs suspensions for LCPT used in the upcoming experiment in the space program SJ-10 satellite.