Figure 6.

(a) SEM images of the air-dried xerogel of 5, where the scale bar represents 2 μm. Widths averaged over at least 70 measurements were 57 ± 23 nm. Other images are provided in the SI (Figures S13–S15). (b) Histogram of the widths of fibers measured from the SEM images (black) and cryo-TEM (red) of 5, along with the distribution expected from a Gaussian distribution (generated from SigmaPlot with a standard deviation of 0.4) around the mean diameter determined by SANS (blue). (c) SANS data for 5 with the model fits with radius (R = 28.5 nm), Kuhn length (50 nm), and length (2 μm) equivalent to the sizes determined from the AFM and SEM images both with and without the power law exponent in order to highlight the differences with the best fits to the data. Other parameters were kept the same as in the best fits. The long dash line is without both polydispersity and the power law model, the medium dash line is with the polydispersity of 0.2 and without the power law model, the dotted line is without the polydispersity but with the power law model (N = 2.5) and the short dash line is with both a polydispersity of 0.2 and a power law model (N = 2.5). Open circles represent the wet gel, open squares the air-dried xerogel, and filled squares the freeze-dried xerogel. The solid red lines depict the model fits to the data as parametrized in Supporting Information (Tables S8). (d) Example of the cryo-TEM image for 5, with a scale bar of 200 nm. The white arrow highlights where two primary fibers seem to wrap around each other. Other images are shown in Figures S18 and S19, Supporting Information.