Improved superabsorbent polymers
This work is devoted to the synthesis, characterization and modification of a class of acrylic-based superabsorbent polymers. The techniques of inverse suspension and solution polymerisations were used for synthesis. Each absorbent was mainly characterised by its equilibrium capacity of water absorption and by the rate of absorption. The swelling characteristics of the polymers were evaluated in terms of change in polymerisation variables which include, type and amount of crosslinker, monomer composition, process of polymerisation, temperature, initiator concentration, monomer concentration and particle size of the product. The swelling dependency on salinity was also examined. In some cases, the base polymer was blended with certain polymers in order to upgrade the swelling properties. A swelling model was devised based on a simple viscoelastic model, i. e. Voigt model, to obtain a better understanding of the effect of the above-mentioned variables on the swelling behaviour. Finally, our materials of choice were compared with some commercial analogues and some further comments have been made for continuing the work.