title: 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 polymer curing. The obtained films are subsequently magnetized at a high magnetic field of 3 T directed parallel to the orientation of the microchains. We prove that the combination of both alignment of the particles along a favorable direction during curing and the 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 than those of the nontreated films with the same particle concentration. Such a process can improve the performance of the magnetic films without increasing the amount of magnetic fillers and, 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 in which large displacements at relatively low magnetic fields are required, such as sensors and drug delivery or microfluidic systems, especially where remote control of valves is requested to achieve appropriate flow and mixing of liquids.
authors: Smart Materials, Nanophysics, Istituto Italiano di Tecnologia , Via Morego 30, 16163 Genova, Italy.
authors: Sophie
authors: S
authors: Marchi
authors: Nanochemistry, Istituto Italiano di Tecnologia , Via Morego 30, 16163 Genova, Italy.|Biological and Environmental Sciences and Engineering Division, King Abdullah University for Science and Technology , Thuwal 23955-6900, Kingdom of Saudi Arabia.
authors: Alberto
authors: A
authors: Casu
authors: Robotics Brain and Cognitive Science, Istituto Italiano di Tecnologia , Via Morego 30, 16163 Genova, Italy.
authors: Franco
authors: F
authors: Bertora
authors: Smart Materials, Nanophysics, Istituto Italiano di Tecnologia , Via Morego 30, 16163 Genova, Italy.
authors: Athanassia
authors: A
authors: Athanassiou
authors: Smart Materials, Nanophysics, Istituto Italiano di Tecnologia , Via Morego 30, 16163 Genova, Italy.
authors: Despina
authors: D
authors: Fragouli
mesh_terms: D020724:Elastomers; D060526:Magnetic Fields; D008422:Materials Testing / Q000379:methods*; D008855:Microscopy, Electron, Scanning; D055620:Optical Phenomena; D011108:Polymers / Q000737:chemistry*
chemical_list: D020724:Elastomers; D011108:Polymers; C036925:elastomeric polymer
keywords: PDMS; ferromagnetism; magnetic actuation; magnetic assembly; microparticles