In Situ Synthesis of Iron Oxide-Polyisobutylene Multifunctional Nanocomposites: Size Control, Magnetic and Mechanical Properties Enhancement

Polymer nanocomposites with precisely controlled nanoparticle size and narrow polydispersity offer substantial potential for multifunctional applications, particularly in energy and healthcare. In this study, we introduce an in situ synthesis approach for creating iron oxide nanoparticle-polyisobutylene nanocomposites, where the nanoparticle size distribution and spatial dispersion are finely tuned by adjusting the polymer concentration and molecular weight. This method allows us to investigate and control the growth dynamics of nanoparticles within the polymer solution, providing insights into how the polymer molecular weight and concentration influence nucleation, growth, and assembly. Beyond achieving precise size control, our approach enables the rational design of nanocomposites with significantly enhanced mechanical strength, evidenced by an increased storage modulus, while preserving their superparamagnetic behavior. This strategy advances the development of high-performance magnetic polymer nanocomposites and opens up possibilities for applications that require both robust mechanical properties and responsive magnetic features, marking a significant step forward in nanocomposite design and functionality.