Abstract:

A superabsorbent polymer(SAP), poly(acrylic acid(AA)/acrylamido-2-methyl-propane sulfonic acid(AMPS))(PAAMPS), was synthesized by inverse suspension copolymerization using the uniform experiment design method. The effect of monomer molar ratios, the neutralization degrees, and the molar fractions of the initiator and the crosslinker(relative to total monomers amount) on the absorbencies in distilled water and 0.9% mass fraction of NaCl aqueous solution were examined. A simulation model of the quadratic regression equation was obtained. Comparison between the simulation and the experimental values was performed for the optimum formula and the single factor experiments. The results show that the simulation values and the experimental values are basically comparative. The optimum polymerization parameters are as follow: the molar fraction of AMPS is 8%, the neutralization degree of the monomers is 75%, the molar ratios of the crosslinker and the initiator(relative to total monomers amount) are 0.035% and 0.17% respectively, concentration of the total monomers is 30%, and the dispersing agent mass concentration relative to total monomers mass is 0.5%, the reaction temperature and time are 70 ℃ and 1.5 h, respectively. The absorbencies in distilled water and 0.9%NaCl aqueous solution under the optimum polymerization parameters are 1.600 and 130 g/g, respectively.

Key words: Super Absorbent Resin, Poly(acrylic acid/acrylamido-methyl-propane sulfonic acid), inverse suspension polymerization, Absorbency, Acrylamido-methyl-propane sulfonic acid, acrylic acid