Physically and Ionically Crosslinked Poly(Itaconic Acid)/Laponite Nanocomposite Hydrogels: Preparation and Erythrosine Dye Release

ABSTRACT This work describes the preparation of physically crosslinked high molecular weight poly (itaconic acid) (PIA)/Laponite hydrogels. In addition, these bio‐based hydrogels were ionically co‐crosslinked using calcium chloride solution for different times. The interactions of the calcium cations with carboxylate groups of PIA were visually checked using the murexide indicator and confirmed with potentiometric titration determining calcium binding capacity, and rheology showing an increase in storage and loss moduli of the hydrogels. This approach enables us to prepare core‐shell materials with a soft hydrogel core and a calcium co‐crosslinked shell. The release kinetics of erythrosine as a model compound of anionic dye were evaluated with common mathematical models. The ionic co‐crosslinking inhibited diffusion of the dye and prolonged its release, showing the application potential of the prepared hydrogels in agrochemical delivery systems.