Synthesis of magnetic responsive poly(NIPAAm-co-VSA)/Fe3O4 IPN ferrogels and modeling their deswelling and heating behaviors under AMF by using artificial neural networks

Abstract

Synthesis of stimuli-responsive hydrogels and modeling their behaviors under stimulus are very important for the use of smart materials in biomedical applications. In the present study, magnetic field responsive and novel poly(N-Isopropylacrylamide-co-Vinylsulfonic acid)/Fe3O4 interpenetrating polymer network (poly(NIPAAm-co-VSA)/Fe3O4 IPN) hydrogel composite (ferrogel) series were successfully synthesized. Firstly, temperature- responsive poly(NIPAAm-co-VSA) IPN hydrogels containing various amount of vinylsulfonic acid (VSA) were synthesized by two polymerization method: emulsion and solution polymerization. Then, Fe3O4 nanoparticles were loaded to hydrogel systems through in situ reduction of Fe2+/Fe3+ ions. Their chemical structures, magnetic properties and surface morphologies were characterized by FT-IR, VSM and SEM analysis techniques. The effects of the VSA content in ferrogel composition on deswelling and heating behavior of ferrogels under various of alternating magnetic fields (AMFs) were experimentally investigated. In order to characterize their heating and deswelling behaviors by magnetic induction heating, heating and deswelling kinetics under 1.37, 1.64 and 1.91 mT magnetic fields were investigated. Their fully swollen states showed complex deswelling and heating behaviors. Artificial neural networks (ANNs) in MATLAB were used to model these behaviors. The ANN models which associated input variables, were able to accurately predict complex deswelling and heating behaviors of magnetic field-responsive poly(NIPAAm-co-VSA)/Fe3O4 IPN hydrogel composites.