Hydrolyzed salep/gelatin-g-polyacrylamide as a novel micro/nano-porous superabsorbent hydrogel: Synthesis, optimization and investigation on swelling behavior


1 Polymer Science and Technology Division, Research Institute of Petroleum Industry (RIPI), Tehran, Iran

2 Department of Chemistry, Payame Noor University, P.O. BOX 19395-3697, Tehran, Iran

3 Polymer Research Laboratory, Department of Chemistry, Sharif University of Technology, P.O. Box 11365-9516, Tehran, Iran


A novel micro/nano-porous superabsorbent hydrogel was synthesized via graft copolymerization of acrylamide (AAm) onto salep (a polysaccharide mixture) and gelatin (a protein) hybrid backbone, after hydrolysis of this system. The Taguchi method was applied for the experiments and standard 18 orthogonal arrays (OA) with seven factors and three levels for each factor proposed trial conditions. Considering the results of 18 trials according to analysis of variance (ANOVA), optimum conditions were suggested. In addition, swelling kinetics, swelling in various organic solvents, the absorbency under load (AUL) and On-Off switching behavior were investigated. Also, the hydrogel formation was confirmed by Fourier transform infrared spectroscopy (FTIR). Surface morphology of the synthesized hydrogels was assessed by scanning electron microscope (SEM) and showed micro/nano-porous structure. Also, the surface area and total pore volume of the optimized hydrogel were measured by Brunauer-Emmett-Teller (BET) technique.