Nanoporous Sodium Carboxymethyl Cellulose-g-poly (Sodium Acrylate)/FeCl₃ Hydrogel Beads: Synthesis and...

Novel sodium carboxymethyl cellulose-g-poly (sodium acrylate)/Ferric chloride (CMC-g-PNaA/FeCl₃) nanoporous hydrogel beads were prepared based on the ionic cross-linking between CMC-g-PNaA and FeCl₃. The structure of CMC and CMC-g-PNaA were elucidated by Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) spectroscopy, and the elemental composition was analyzed by energy dispersive X-ray analysis (EDX). The physicochemical properties of the CMC-g-PNaA/FeCl₃ hydrogel beads were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM) and thermogravimetric analysis (TGA). The swelling percentage of hydrogel beads was studied at different time periods. The obtained CMC-g-PNaA/FeCl₃ hydrogel beads exhibited a higher nanoporous morphology than those of CMC-g-PNaA and CMC beads. Furthermore, an AFM image of the CMC-g-PNaA/FeCl₃ beads shows granule type topology. Compared to the CMC-g-PNaA (189 °C), CMC-g-PNaA/FeCl₃ hydrogel beads exhibited improvement in thermal stability (199 °C). Furthermore, CMC-g-PNaA/FeCl₃ hydrogel beads depicted a higher swelling percentage capacity of around 1452%, as compared to CMC-g-PNaA (1096%). Moreover, this strategy with preliminary results could be useful for the development of polysaccharide-based hybrid hydrogel beads for various potential applications.