Effects of Montmorillonite and Acrylic Acid on the Superabsorbent Polymer Based on Xanthan

Abstract

Superabsorbent polymers, which have been used for many applicaions, are an important class of polymers. Superabsorbent polymer based on organic montmorillonite (MMT) and xanthan gum(XG) were prepared by by free-radical graft polymerization of aceylic acid on XG in aqueous solution as a free radical initiator, and then organic montmorillonite (OMMT) was introduced as filler into superabsorbent. The effects of montmorillonite and xanthan on the swelling behaviour of the superabsorbent polymer had been studied in detail. Under the optimal synthesis condition, where the temperature was 65°C, the ratio between the AA monomers and XG was m (XG) : m(AA) = 4 : 1, the weight rate of the initiator and the cross-linker were 1.2% and 0.07%, and the neutralization degree of AA was 70%, the product attained the best water absorbency of 882 g/g in distilled water and 107 g/g in 0.9 wt.% NaCl solution.