A Study of Polymer/Clay Hybrid Composite Sorbent-Based AAm/SMA Hydrogels and Semi-IPNs Composed of -Carrageenan and Montmorillonite for Water and Dye Sorption

A series of chemically cross-linked hybrid composite hydrogel systems containing polysaccharide/clay polyelectrolyte based on the acrylamide/sodium methacrylate (AAm/SMA) and -carrageenan and clay such as montmorillonite were synthesized with free radical solution polymerization by using ammonium persulfate/N,N,N',N'-tetramethylethy lenediamine as a redox-initiating pair in the presence of poly(ethylene glycol) diacrylate as a cross-linker. Fourier transform infrared spectroscopy (FT-IR) analysis and scanning electron microscopy (SEM) technique were applied for characterization. The hydrogels, the semi-interpenetrating polymer networks (semi-IPNs), and the hybrid composite hydrogel systems that were synthesized in this study have shown high water absorbency. Some swelling and diffusion properties were calculated, and they were discussed for the hybrid hydrogel systems prepared under various formulations. They were used in experiments on sorption of water-soluble cationic dye such as Safranin T (ST). The sorption of ST into the polymeric systems was studied by a batch sorption technique at 25 degree C. For equilibrium sorption studies, dye removal capacity, adsorption percentage, and partition coefficient of the hydrogels, the semi-IPNs, and the hybrid composite hydrogel systems are investigated. Consequently, the hydrogels, the semi-IPNs, and the hybrid composite hydrogel systems developed in this study could serve as a potential device for water and dye sorbents. Some materials such as the hydrogels, the semi-IPNs, and the hybrid composite hydrogel systems developed in this study with the ability to absorb water in high amounts could be used as a water and dye sorbents because of their potential applications in agriculture, environment, separation processes, and water purification.