Equilibrium properties of magnetic filament suspensions

Abstract

Langevin dynamics is used to study equilibrium properties of the suspension of magnetic filaments (chains of nanoparticles permanently crosslinked with polymers). It is shown that the filament suspension generally has larger magnetic susceptibility than the system of unlinked nanoparticles with the same average particle concentration. However, actual susceptibility gain strongly depends on length and flexibility of filaments. It also shown that in a strong gravitational (centrifugal) field sedimentation profiles of filaments are less homogeneous than that of unlinked particles. The spatial distribution of filaments weakly depends on the intensity of interparticle dipole-dipole interactions.Comment: 8 pages, 6 figures, accepted for publication in Journal of Magnetism and Magnetic Material

Adsorption transition of a grafted ferromagnetic filament controlled by external magnetic fields

“…Numerous computer simulations of magnetic gels, elastomers, and filaments are based on bead-spring representations with different levels of detail [47][48][49][50][51][52]. Regarding particle-based simulation of MFs, since the main role of the polymer components is to provide the permanent linking of the magnetic particles in the chain, the most convenient approach is to represent them implicit by means of simple elastic bonding potentials, whereas the particles are usually simulated as beads with point magnetic dipoles [46,[53][54][55][56]. Our mesoscale model of the grafted ferromagnetic filament is based on such an approach and is very similar to those used in our previous studies on these systems [32][33][34][35]46].…”

Adsorption transition of a grafted ferromagnetic filament controlled by external magnetic fields

“…Numerous computer simulations of magnetic gels, elastomers and filaments are based on bead-spring representations with different levels of detail [47][48][49][50][51][52]. Regarding particle-based simulation of MFs, since the main role of the polymer components is to provide the permanent linking of the magnetic particles in the chain, the most convenient approach is to represent them implicit by means of simple elastic bonding potentials, whereas the particles are usually simulated as beads with point magnetic dipoles [46,[53][54][55][56]. Our mesoscale model of the grafted ferromagnetic filament is based on such approach and is very similar to those used in our previous studies on these systems [32][33][34][35]46].…”

The structure of clusters formed by Stockmayer supracolloidal magnetic polymers

“…Modern experimental techniques allow the stabilisation of dipolar clusters by polymer crosslinking, forming supracolloidal magnetic polymer-like structures [14][15][16][17]. In general, the behaviour of chain-like magnetic SMPs has been actively investigated in experiment [18][19][20][21], theory [22][23][24] and coarse-grained computer simulations [25][26][27][28]. All these works agree that SMPs represent a promise for potential medical and microfluidics application [29,30].…”