Synthesis and properties of sepiolite/poly (acrylic acid-co-acrylamide) nanocomposites

Novel hydrogel nanocomposites, based on sepiolite, acrylic acid (AA), acrylamide (AM), and N,N'-methylenebisacrylamide (MBA), were synthesized by solution copolymerization. The structure, morphology and liquid absorbency of these composites were investigated through FTIR, SEM and the like. The influences of sepiolite, crosslinker content, initiator dosage, neutralization degree of AA and molar ratio of AA/AM on the distilled water absorbency (Q(w)), physiological saline solution absorbency (Q(p)) were discussed in detail. Results showed that needleshaped sepiolite dispersed in nanoscale, and the grafting of AA and/or AM on the sepiolite surface occurred. Compared with the sepiolite-free hydrogel, sepiolite contributed to liquid absorbency, and at its weight content of 15.0%, Q(w) and Q(p) were enhanced as high as 11.6% and 14.5%, respectively.