Preparation of a Super-Absorbent Polymer with Gracilaria lemaneiformis Residue under Microwave Irradiation and Its Performances Research

To prepare a kind of super-absorbent polymers by gracilaria lemaneiformis residue, a novel super-absorbent polymer was synthesized by means of microwave irradiation. Acrylic acid and acrylamide were grafted onto gracilaria lemaneiformis residue by using potassium per-sulfate as an initiator in the presence of N, N´ methylenebisacrylamide as a cross linker. The univariate analysis was visually analyzed to choose the optimal conditions. The optimum conditions show that the initiator dosage is 0.5%, the cross linker dosage is 0.04%, the mass ratio of acrylic acid and acrylamide is 5:2, the neutralization degree of acrylic acid is 80%, the time of microwave irradiation is 4 min, the mass ratio of gracilaria lemaneiformis residue and monomers is 1:2 and the power of microwave irradiation is 500 W respectively. Under the optimum condition, the absorption capacities of the resultant product for the deionized water, tap water and 0.9% NaCl solution can reach 650.1 g/g, 468.5 g/g and 104.3 g/g, respectively. The performance test of the resultant product indicates that it has faster absorbent velocity and excellent water retention.