Abstract:

A novel guar gum-g-poly(acrylic acid) superabsorbent was synthesized by the solution copolymerization between natural guar gum (GG) and acrylic acid (AA) using ammonium persulfate (APS) as an initiator and N, N′-methylenebisacrylamide (MBA) as a crosslinker.The effects of MBA concentration on the swelling kinetics and water absorbency of the superabsorbent were investigated, and the swelling behavior of the superabsorbent in various hydrophilic organic solvent/water mixture solutions, various cationic (NaCl, CaCl₂ and FeCl₃) and anionic (KNO₃, K₂SO₄ and K₃PO₄) saline solutions at different ion strengths were investigated, and the water-retention properties of the superabsorbent at room temperature and high temperature were also determined.The results showed that the superabsorbent was sensitive to hydrophilic organic solvent, and its water absorbency sharply decreased with increasing concentration of hydrophilic organic solvents; the water absorbency of the superabsorbent in various saline solutions decreased with the increase of ion strength.