Novel smart materials from Pluronic F127 and akaganeite (β-FeOOH) nanorods

Hydrogels are soft materials with a 3D internal network-like structure with water as a significant component. The word "smart" corresponds to a direct response to changes in environmental conditions like pH, light, pressure, temperature, and electric and magnetic fields. To develop simple, cost-efficient, and biocompatible hydrogels with multiple stimuli-responsive behaviours, we made novel smart material (thermoresponsive hydrogels) consisting of akaganeite (β-FeOOH) nanorods and pluronic F127 (PF127). Though akaganeite has been used as a precursor to preparing stable iron-oxide states (e.g., hematite and magnetite), the studies on nanorods to be used as the main component in hydrogels are at the nascent stage. This talk presents a detailed methodology of akaganeite nanorod synthesis by a simple sol-gel process. XRD, spectroscopy, electron microscopy, and light scattering experiments characterize its properties. A phase diagram and thermoresponsive behaviour based on rheological experiments with flow curves, amplitude and frequency sweep are established for 20 wt% PF127 with low concentrations (0.1- 0.1 wt%) of β-FeOOH nanorods. Finally, a plausible physical mechanism is proposed to fundamentally understand how and why this unique responsive behaviour appears based on different interactions in the nanocomposite system.