Rheological Properties of Bent-Core Liquid Crystals
We show that bent-core liquid crystalline materials exhibit non-Newtonian flow in their optically isotropic liquid phase. We conjecture that this behavior is due to the existence of nanostructured, fluctuating clusters composed of a few smectic-like layers. Shear alignment of these clusters explains the shear thinning observed in bent-core liquid crystals having either a nematic phase or non-modulated smectic phase. By contrast, smectogens having a modulated smectic phase do not shear thin at low shear rates, but even show a slight shear thickening which may be due to entanglements of wormlike and/or helical clusters.
Bailey, C.; Fodor-Csorba, Katalin; Gleeson, Jim T.; Sprunt, Samuel N.; and Jákli, Antal (2009). Rheological Properties of Bent-Core Liquid Crystals. Soft Matter 5(19), 3618-3622. Retrieved from http://digitalcommons.kent.edu/cpippubs/48