Scientists from the Laboratory of Theoretical Physics at JINR and research centres in Romania and the Czech Republic conducted an in-depth study of the electrical and magnetic properties of a polypyrrole nanotubes/magnetite nanoparticles (PPyM) material embedded in a silicone oil matrix. The distinct electrical, magnetic, and rheological modulation capabilities demonstrated by this composite render it as a promising candidate for advanced applications, such as sensory technology, actuation systems, and energy storage solutions.

One of the key findings of this study is the dual nature of the composite, namely its behaviour, similar to both electro- and magnetorheological suspensions This unique duality is evident in its response to varying electric and magnetic field intensities.

The research focuses on studying the electrical properties of the composite, including its dielectric permitivity and dielectric loss factor. Additionally, the scientists conducted an extensive analysis of its rheological characteristics, with an emphasis on how its viscosity changes in response to electromagnetic stimuli. This property notably underscores the material’s dual-responsive nature.

Employing a custom experimental design, the researchers integrated the composite into a passive electrical circuit element subjected to alternating electric fields. This methodological approach made it possible to precisely measure the material’s response in terms of resistance, capacitance, and charge under various field conditions.

The findings reveal substantial changes in the material’s electrical conductivity and rheological characteristics, which are significantly depend on the intensity of the applied fields. These results enhance the understanding of electro-magnetorheological properties of PPyM-based magnetic composites, and highlight their potential in applications involving smart materials.

The article was published in Smart Materials and Structures in May 2024. Among the authors is a Deputy Director of the Laboratory of Theoretical Physics at JINR, Eugen Anitas.