Congratulations to Johanna and co-authors for the publication in Langmuir of the article "Enhancing Self-Assembly in Cellulose Nanocrystal Suspensions Using High-Permittivity Solvents". The team studied dispersion of Cellulose Nanocrystals (CNC) and the associated liquid crystal formation in water and in non-aqueous but polar solvents. Johanna developed a new method for exchanging the solvent of CNC suspensions from the water used during synthesis to formamide, N-methylformamide (NMF) and N,N-dimethylformamide (DMF), without inducing aggregation of the nanorods. She found striking differences between the solvents concerning the liquid crystal formation. The four solvents span a large range of dielectric permittivity, a parameter that turns out to be of key importance. The cholesteric helical superstructure develops much faster in high-permittivity NMF than in water and the pitch depends much less on CNC concentration than when water is the solvent. In low-permittivity DMF the first trace of liquid crystal formation coincides with kinetic arrest of the whole sample, preventing any helix formation since an equilibrium liquid crystal phase never develops. We propose that this is due to aligned aggregation of the CNC nanorods. The experimental results are corroborated by computer simulations done in Tanja Schilling's group, which furthermore indicate that the nematic order parameter goes up for high-permittivity solvents.

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We regret that the published Acknowledgments section unfortunately did not mention that Rick Dannert is a member of the Laboratory for the Physics of Advanced Materials of the University of Luxembourg and that this group kindly made their equipment (AFM, rheometer and refractometer) available for some of the experiments described in the paper. We deeply apologize for having forgotten this information in the published paper. Here we would like to express our deep gratitude for the support from the Laboratory for the Physics of Advanced Materials.

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