Congratulations to Camila on her first scientific article since she joined our group: "Equilibrium Liquid Crystal Phase Diagrams and Detection of Kinetic Arrest in Cellulose Nanocrystal Suspensions" by Camila Honorato Rios, Anja Kuhnhold, Johanna Bruckner, Rick Dannert, Tanja Schilling, and Jan P.F. Lagerwall, is now published (open access) in Frontiers in Materials, section Biomaterials. In the article, we study the phase diagram and helical pitch behavior in the cholesteric phase of aqueous suspensions of cellulose nanocrystal (CNC) nanorods, as a function of mass fraction, surface charge and concentration of added inorganic salt. The study is a combined experimental and computer simulation thrust, where our group's experimental data are complemented by simulation results by Anja Kuhnold, in the group of Prof. Tanja Schilling. An unexpected—and very interesting—observation is that the nature of the cholesteric-isotropic phase transition appears to change with ionic strength of the solvent. While it is strongly first order, as expected for lyotropic liquid crystals of hard-rod colloids, at low ionic strength, the barrier between isotropic and cholesteric phase appears to decrease upon salt addition, such that the isotropic phase becomes increasingly turbid as the ionic strength is increased. This is what is illustrated in the image, the concentration written at the top of each vial referring to the added salt; the CNC mass fraction is the same in all vials. The phenomenon reminds of the strong light scattering typical of critical fluctuations, normally seen only in the vicinity of a second order phase transition. You can read and download the paper, without subscription (Frontiers of Materials is an open access journal), by clicking on this link.

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