UC Riverside

Magnetic nanomaterials have attracted significant attention due to their unique properties that allow for remote, reversible, and rapid tuning under external magnetic fields. Integrating magnetic nanostructures and polymers creates multifunctional materials with advanced properties. These composite nanostructures combine the magnetic responsiveness of magnetic nanoparticles with the colloidal stability and stimulus responsiveness of polymers. This dissertation focuses on magnetic nanostructure-polymer integration for advanced functionalities.In the first part, we studied the heating performance of magnetic nanoparticles for thawing cryopreserved biological samples. By optimizing nanoparticle size and surface polymer coating, we achieved a balance between heating efficiency, colloidal stability, and biocompatibility. These integrated nanomaterials were successfully applied as the first nanowarming case for thawing cryopreserved porcine iliac arteries. In the second part, we delve into polymer-mediated colloidal stability and introduce swellable polymer-coated superparamagnetic nanoparticles for controlled assembly into one-dimensional photonic superstructures. The resorcinol-formaldehyde (RF) polymer coating provides steric hindrance to balance magnetic dipole interactions during the assembly of photonic nanochains. Adjusting the swelling behavior of RF polymers allows modulation of interparticle spacing and diffraction wavelength, creating dynamically tunable responsive optical materials in non-aqueous environments. In the third part, we further explore the assembly behavior of magnetic nanomaterials and their enhanced functions by integrating responsive polymers. Functionalization of magnetic nanorods with polyaniline coatings creates dual-responsive chiral superstructures that exhibit both magnetic and pH responsiveness, allowing dynamic tuning of their chiroptical properties. This dual responsiveness enables the development of advanced chiroptical switches and reconfigurable information encryption systems, showcasing potential applications in optical devices and information security. In the fourth part, we explore a novel multi-responsive plasmonic coupling system that integrates responsive polymer layers with plasmonic metal nanostructures through a space-confined seeded-growth method. The hybrid nanostructures, leveraging the unique responsive swelling behavior of functional polymers, allow dynamic tuning of interparticle distance of plasmonic nanoparticles and their plasmonic coupling properties via external stimuli. This integration expands the possibilities for developing innovative materials with tailorable optical properties, suitable for applications such as anticounterfeiting and adaptive optical materials.