SKM 2023 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

CPP: Fachverband Chemische Physik und Polymerphysik

CPP 45: Emerging Topics in Chemical and Polymer Physics, New Instruments and Methods

CPP 45.2: Talk

Thursday, March 30, 2023, 09:45–10:00, ZEU 255

Bulk magneto-mechanical response of magnetic filaments in applied magnetic fields — •Deniz Mostarac and Sofia Kantorovich — Univesity of Vienna,Vienna,Austria

Incorporating magnetic nanoparticles within permanently cross-linked structures, opens up the possibility for synthesis of complex, highly magneto-responsive systems. Magnetic filaments (MFs) are polymer-like chains of magnetic, nano-sized colloids, and are a promising platform for engineering novel, magnetically controlled filtering and flow control elements in micro-fluidic devices. The interplay between central attraction forces, and anisotropic, dipolar interactions is the key factor when tuning the macroscopic response of MFs. In this contribution, we show that taking in to account nonlinear contributions to the magnetisation of super-paramagnetic colloids is essential to capture the bulk, magneto-mechanical response of MFs consisting of magnetisable colloids. In the presence of central attraction forces, we report substantial differences in the equilibrium structure of filament clusters, and the mechanical and magnetic response of filament suspensions, to static and time dependant magnetic fields. While on the level of a single filament, magneto-mechanical properties are in general more dependant on the crosslinking approach than on the magnetic nature of colloids, in bulk, the long-range nature of dipolar interactions in quasi-infinite systems makes up for a tremendous difference, and underlines the necessity of a sophisticated model of magnetic colloids that can be magnetised by the presence of magnetic and dipole fields.