Dielectric properties of polyacrylamide and its utilization as a hydrogel

Some of the dielectric properties of polyacrylamide are given such as the variation of the dielectric constant, ε′, and the dielectric loss, ε′′, and the power factor tan δ with the applied frequency from 105 to 107 Hz within the temperature range 20–50°C. The dielectric dispersion and absorption bands appear within these ranges of frequencies and temperatures. The relaxation process is explained and discussed, also the relaxation times are calculated and the activation energy and entropy change of dielectric relaxation are calculated from the usual rate equation and discussed. The process of polymerization of polyacrylamide is explained through comparing the dielectric properties of the monomer (acrylamide) and the polymer. Out of two approaches to obtain a hydrogel from polyacrylamide, the physical approach is thoroughly investigated and discussed.