The results from measuring the steady shear rate of the
water/C16SE/LA system at 30 ◦C and at various W1 values are shown
in Fig. 1. The weight fraction of water in the entire system was
fixed at 0.9. Viscosity was nearly constant at a low shear rate and
decreased above a certain shear rate for all of the samples. The point
at which the viscosity started to decrease shifted to the lower shear
rate when W1 increased from 0 to 0.04 and changed direction when
W1 was greater than 0.06.
We can obtain a zero-shear viscosity value (0) by extrapolating
a viscosity curve in Fig. 1 to a shear rate of zero. Fig. 2 is a plot of
0 for various FA systems against W1. As can be seen in Fig. 2, the
zero-shear viscosity increased with W1 and then decreased after
a maximum viscosity for all of the systems. This type of behavior