Figure 6
From: Orientation in multi-layer chitosan hydrogel: morphology, mechanism and design principle
Rheological properties of CS solution.
(a) Dependence of zero-shear viscosity (ηo) on c(CS) at 25°C. Insets are SEM images corresponding to c(CS) < 0.5 wt.% and c(CS) > 1.0 wt.%, respectively; (b) Dependence of the steady shear viscosity on the shear rate for CS solutions with various concentrations at 25°C, the critical shear rates are as follows: 0.2 ~ 0.4 s−1, 1.0 ~ 2.5 s−1, 4 ~ 6 s−1, 7 ~ 10 s−1, 25 ~ 39 s−1, 63 ~ 100 s−1, 130 ~ 158 s−1, which were determined by first order derivative; (c) Dependence of the steady shear viscosity on the shear rate for CS solution at different pH, including unreacted CS solution (pH = 2.7) and CS solution near gelation pH (pH = 6.5).
