Modulating Mechanical Properties of Magnetc-Responsive Polymeric Nanocomposites for Technological Applications

Stimulus-responsive polymeric nanocomposites exhibit properties modulated by incorporated nanostructures in response to stimuli (temperature, light, magnetic fields, etc.). These nanocomposites can act as intelligent materials, being interesting applications in technological areas such as robotics, automotive, packaging, textiles, among others. In this study, we developed nanocomposites based on poly(butylene-adipate-co-terephthalate) (PBAT) and Fe3O4@poly(1,4-butanediol) nanoparticles (IONPs), exploring their mechanical behavior under a magnetic field. The nanocomposite films were produced via tape casting, a method where a dispersion (PBAT and IONPs) is spread over a surface using a controlled blade (doctor blade) to produce a tape with uniform height. The films demonstrated homogeneity and high transparency, indicating excellent IONPs dispersion. By varying the IONP/PBAT mass ratio, films exhibited magnetic properties that increased with NPs content. In addition, thermal analysis (DSC and TGA) suggested that IONPs possess a polymeric molten shell, potentially indicating fluid iron-like behavior at room temperature, which could pave the way for magnetically responsive materials. The results included slight changes in the Young's modulus with the application of an external magnetic field, whose reflects on the IONPs orientation and stiffens the material. These findings hold promise for modulating mechanical properties by external stimuli and expanding the applications for technological areas, which can be used for the development of more effective and smart robotic systems.