Highly Magneto-Responsive Elastomeric Films Created by a Two-Step Fabrication Process

Abstract

An innovative method for the preparation of elastomeric magnetic films with increased magneto-responsivity is presented. Polymeric films containing aligned magnetic microchains throughout their thickness are formed upon the magnetophoretic transport and assembly of microparticles during the polymer curing. The obtained films are subsequently magnetized at a high magnetic field of 3 T directed parallel to the microchains orientation. We prove that the combination of both, alignment of the particles along a favorable direction during 2 curing, and subsequent magnetization of the solid films induces an impressive increase of the films' deflection. Specifically, the displacements reach few millimeters, up to 85 times higher compared to the non-treated films with the same particles concentration. Such process can improve the performance of the magnetic films without increasing the amount of magnetic fillers, thus without compromising the mechanical properties of the resulting composites. The proposed method can be used for the fabrication of magnetic films suitable as components in systems where high displacements at relatively low magnetic fields are required, such as sensors, drug delivery or microfluidic systems, especially where remote control of valves is requested to achieve appropriate flow and mixing of liquids.

Tunable, Flexible Composite Magnets for Marine Monitoring Applications

“…In order to provide a more versatile solution for magnetic-based underwater monitoring systems, we propose the use of composite magnets. Mixing magnetic fillers into a soft and flexible carrier matrix has been recently proposed for a new generation of magnetic composite materials [8,21,22] and exploited in biomedical [23][24][25][26] , robotics [27][28][29][30][31] , and automotive [32][33][34] fields.…”

Stimulus-active polymer actuators for next-generation microfluidic devices

“…With increasing pressure in the channel, the valve switches into the open position, where the switching point depends on the weight ratio in the flexible membrane and the strength of the composite magnet underneath. In [31], a method for preparing elastomeric magnetic films with increased responsiveness to magnets was presented. This was achieved by aligning the magnetic particles throughout the thickness of the elastic film during the curing process and subsequent magnetization.…”

Magnetic Responsive Polymer Nanocomposites with In–situ Tunable Anisotropy by Magnetic Self‐Organization

“…They can be operated in many different media, including air, vacuum, conducting and non‐conducting liquids, as long as the actuation environment is magnetically transparent . Furthermore, the MRPNCs with highly magnetic anisotropy are reported to efficiently strengthen the film deflection and the matrix modulus in comparison of the composites with random distribution of magnetic particles. In these composites, the magnetic particles distribute as chain‐like structures since the magnetic field has been applied during the prestructure process.…”