A super water absorbent resin was synthesized by means of aqueous solution polymerization from etherificated sodium alginate

acrylic acid and polyvinyl alcohol，with N

N′-methylenebisacrylamide as crosslinking agent

(NH4)2S2O8-NaHSO3 as initiator.The equilibrium water contents of the resin in various pH buffer solutions and saline solution were determinated and compared.In acidic solution

the swelling of the water absorbent resin was controlled by —COO- protonation and followed non-Fickian transport.In alkaline solution

the swelling was controlled by solvent diffusion and followed Fickian transport.When the pH of solution was increased

the equilibrium water content of the resin increased.When ionic strength was close to each other

water absorbency in various pH buffer solutions was relatively lower than that in monovalent metal saline solutions but higher than that in divalent metal saline solutions.The mechanism of resin-solvent interaction was also studied.