Isotropic to Nematic Transition in Sediments of Colloidal Rods

This study focuses on developing a colloidal system to investigate the structural properties of sediments from suspensions of colloidal rods. SU-8 colloidal rods have been prepared using a high shear-based method and have been filtered by centrifugation to separate by rod length and mitigate the polydispersity of the rods. Rod suspensions are then loaded into capillary tubes and sediments are formed by high g centrifugation. Preliminary results indicate that some conditions lead to dense, nematically ordered sediments while others produce isotropic, low density sediments. The goal of this work is to investigate the impact on sediment properties of modifications of the rod size and aspect ratio, by varying synthesis conditions, as well environment alteration, including centrifugation rate, and solvent. Determination of density and ordering is performed using confocal microscopy.