and cross-slot (extensional) microchannels in Figures and Imaging of PII-2T in pure CB reveals elongated, semiflexible fibril aggregates with diameters on the order of 10 nm and lengths ranging broadly from ~100 nm to several microns. Fibril aggregates are also present with the addition of 10% DMF and have similar diameters. However, these fibrils appear to be more rigid, having more rod-like conformations. Furthermore, some larger scale agglomerates of rigid fibrils can also be seen with lengths greater than 1 μm (Figure ).