Title : Formulation and Characterization of Ferrogels Based on Agar Gum and Octenyl Succinic Anhydride (OSA) Starch
Abstract:
Physicochemical and rheological analyses are carried out on ferrogels based on Agar gum in combination with octenyl succinic anhydride (OSA) starch in the presence of magnetic nanoparticles (MNPs) coated with a stabilizing agent (PNiPAAm). The objective of this work is to prepare nanocapsules of MNPs coated with OSA starch present in a rigid network of Agar to obtain a nanocomposite gel (ferrogel). It is found that the effect of MNPs on the properties of ferrogels has a direct relationship with PNiPAAm/OSA starch interactions. The results obtained show that the ferrogels have stable thermal properties and a high melting point (99.7 °C) for high concentrations of MNPs (0.1%). The rheological properties show that this concentration (0.1%) has a negative effect on the crosslinking of Agar, therefore a drop in viscosity. In addition, it is shown that each pore comprises three populations of MNPs (primary: 3–4 nm, secondary: 6–9 nm, and clusters: ≥12 nm). Moreover, it is found that MNPs are coated with OSA starch. In addition, the prepared materials possess at low concentration of MNPs an interesting stiffness and uniform surface morphology with a minimum of clusters leading to stable systems that can be used as biomaterials in nanomedecine.