Imbibed salts and pH-responsive behaviours of sodium alginate based eco-friendly biopolymeric hydrogels-A solventless approach

摘要

In this study, Sodium alginate was chosen to synthesis a series of pH-sensitive hydrogel due to naturally abundant, renewable, non-toxic, water-soluble, biodegradable and biocompatible. By virtue of these advantages, sodium alginate has attracted researchers in industrial and medical fields. The hydrogel was synthesised from Sodium alginate (SA), ethylene glycol and acrylic acid by using condensation followed by free radical polymerization in the presence of water. The formations of synthesised hydrogel were confirmed by FT-IR spectral analysis. The parameters of swelling equilibrium % were carried out in distilled water and various buffer solution of pH from 4.0 to 10.0. The surface morphology of the hydrogels was examined by SEM analysis which supported the swelling behavior of hydrogels. Furthermore, the salt responsive behaviour has also been studied with monovalent, divalent and bivalent salts viz., NaCl, CaCl2, and AlCl3. Swelling equilibrium was lower in multivalent anion salt solution than in monovalent anion salt solution, i.e., Al~(3+) < Ca~(2+)< Na~+. The synthesized biopolymeric hydrogels might be used in biomedical, agrochemical release, environmental application and also used to produce hygiene products such as diapers etc.