Swelling of crosslinked polyacrylic acid

摘要

This paper presents the results of a swelling study of an anionic polymer i.e. crosslinked polyacrylic acid in water and media simulating biological fluids such as artificial gastric juice (AGJ) and artificial intestinal juice (AIJ). It was shown that the kinetics of swelling could be presented, not only by the kinetic equation for the normalized degree of swelling (q) but also by the degree of swelling (α). The mechanism of polyacrylic acid swelling in water is Fickian diffusion, while in artificial media simulating biological fluids it is non-Fickian diffusion.