Thermomechanical properties of confined magnetic nanoparticles in electrospun polyacrylonitrile nanofiber matrix exposed to a magnetic environment: structure, morphology, and stabilization (cyclization)

Abstract

Electrospun metal oxide-polymer nanofiber composites hold promise for revolutionizing biomedical applications due to their unique combination of electronic and material properties and tailorable functionalities. An investigation into the incorporation of Fe-based nanofillers for optimizing the polyacrylonitrile matrix was conducted, where the systematic and organized arrangement of inorganic components was achieved through non-covalent bonding. These carefully dispersed nanomaterials exhibit the intrinsic electronic characteristics of the polymers and concurrently respond to external magnetic fields. Electrospinning was utilized to fabricate polyacrylonitrile nanofibers blended with Fe2O3 and MnZn ferrite nanoparticles, which were thermomechanically, morphologically, and spectroscopically characterized in detail. With the application of an external magnetic field in the course of dynamic mechanical measurements under tension, the storage modulus of the glass transition Tg of PAN/Fe2O3 rises at the expense of the loss modulus, and a new peak emerges at similar to 350 K. For the PAN/MnZn ferrite nanofibers a relatively larger shift in Tg (from similar to 367 K to similar to 377 K) is observed, emphasizing that in comparison to Fe2O3, Mn2+ ions in particular enhance the material's magnetic response in MnZn Ferrite. The magnetic oxide particles are homogenously dispersed in polyacrylonitrile, corroborated by high-resolution scanning electron microscopy. Both nanopowder additions lead to a slight shift of the peak towards larger angles, related to the shrinkage of the polymer. Produced nanofibers with high mechanical and heating efficiency can optimize the influence of the intracellular environment, magnetic refrigeration systems and sensors/actuators by their magnetic behavior and heat generation. The incorporation of Fe-based nanofillers for the optimization of the nanofiber of polyacrylonitrile matrix was achieved through non-covalent bonding. Produced nanofibers can optimize the influence of the intracellular environment.Universitt Wien [E-COST-GRANT-CA21101-28134500]; COST Action CONTEXT [CA17107]; COST (European Cooperation in Science and Technology); University of ViennaWe would like to thank for the Short-Term Scientific Mission (STSM) grant (E-COST-GRANT-CA21101-28134500) for ASS between 29/09/2023 -08/10/2023 by the Prof. Dr Wilfried Schranz (Host Institution Faculty of Physics, Physics of Functional Materials, University of Vienna). Empa acknowledges the helpful advice and support of A. Gogos and E. Perret regarding microscopic and spectroscopic investigations. This publication is also based upon work from the COST Action CONTEXT (CA17107), supported by COST (European Cooperation in Science and Technology). Open access funding provided by University of Vienna