Role of Water in Dielectric Properties of Starch Membranes - Natural Polymers, Biopolymers, Biomaterials, and Their Composites, Blends, and IPNs - page 295

The value of the maximum value for the dielectric loss is small at low temperatures (~
0.2 at 0°C). As the temperature increases yet another relaxation is observed. When the
sample is held at high temperature at 150°C, the dielectric loss still exist showing that
the starch is not disintegrated at such temperature.

Figure 4a Figure 4b

The variation of the dielectric loss (ε'') as a function of frequency for various
temperatures for starch in 0% humidity is shown in Figure 5a and 5b. In this case, the
dielectric loss values are higher than that for starch in 0% humidity. At low tempera-
tures, a broad relaxation is observed. The position of the frequency maxima increases
with increasing temperatures. As the sample approaches 0°C yet another relaxation is
observed. ε'' der was used instead of ε'' to better resolve the spectra due to high values
for dielectric loss caused by high conduction loss. The spectra had nearly the same
values at high temperatures (~ 80°C).

Figure 5a Figure 5b