The results are shown in Figure , where the peak relaxation time is determined for PII-2T in CB to be 60 μs at 3 mg/mL, 68 μs at 4 mg/mL and 97 μs at 6 mg/mL. As shown in Figure for 8 and 10 mg/mL the lack of an inflection point in the retardance profile results in the peak relaxation time being undeterminable. However, it must be longer than those at lower concentrations and should therefore be >100 µs. This is again in agreement with our observations that the presence of inter-fibril interactions start to occur as concentration approaches ~10 mg/mL. We do not determine the relaxation time distribution for PII-2T in CB/DMF as we observed alignment and faint birefringence at very weak flows (~0.02 μL/min), indicating a very slow relaxation time which is to be expected considering the large size of the fibril agglomeration. Because birefringence was observed below our lowest flow rate, the relaxation time of the CB/DMF aggregates must be greater than the corresponding inverse strain rate, or >1 ms.