Effect of Compositional Parameter on Swelling Behavior of Cationic Acrylamide Based Superabsorbent in Free Equilibrium Swelling and Under Load Condition

A series of cationic based superabsorbent polymers (SAPs) were prepared by solution crosslinking copolymerization of acrylamide (AAm) and [3-(methacryloylamino) propyl] trimethyl ammonium chloride (MAPTAC) using N,N’ methylene-bis-acrylamide (NMBA) as crosslinking agent. Taguchi’s method for design of experiments were used to obtain the optimum condition as well as investigating the effects of various parameters at gel formation such as total monomer concentration (TMC), cationic monomer and crosslinking agent concentration upon swelling behavior of superabsorbents in free and under load conditions. It was found that by increasing crosslinking agent and total monomer concentration absorbency decreased in free equilibrium swelling while it increased under load conditions. By raising cationic monomer MAPTAC, swelling apacity and rate of hydrogels were increased in both free and under load conditions. The effect of external salt solution composed of ions with different valency on the swelling behavior of the superabsorbent was also investigated.

Keywords:

superabsorbent , cationic , swelling behavior , acrylamide , absorbency under load