Polymer Bulletin, Vol.71, No.4, 839-854, 2014
Environmental sensitive hydrogel for purification of waste water: part 1: synthesis and characterization
We report the synthesis of a novel poly (acrylate-acrylic acid-co-maleic acid) hydrogel by the copolymerization of acrylic acid and maleic acid in aqueous media using N,N'-methylenebisacrylamide (NMBA) as cross linker and ammonium persulfate as initiator. Hydrogels with varying concentration of the cross linker and monomer were prepared and were characterized using Fourier transform IR spectroscopy and thermogravimetry. The mechanical properties of the gel were investigated using tensile strength measurements and the morphology was confirmed with environmental scanning electron microscopy at room temperature. Water absorbency studies of the hydrogels revealed that synthesized hydrogels are responsive towards ionic strength and pH of the swelling medium. Cross link density and tensile strength were found to increase with increase in the NMBA content which was optimized from swelling experiments. Reswelling experiments of the hydrogel revealed that the synthesized hydrogel is a reusable material and it indicates its applicability in the waste water purification.