Magnetically tunable transparency for magnetorheological elastomer films consisting of polydimethylsiloxane and Fe3O4 nanoparticles

In this research, we demonstrate magnetically tunable transmittance for the magnetorheological elastomer films comprised of polydimethylsiloxane and Fe₃O₄ nanoparticles. The films bearing anisotropic and isotropic microtexture were prepared with and without magnetic field, respectively. The usage of toluene as diluent during the film preparation process leads to the increased tunable range of the magnetically induced transparency in comparison with our previous results. For the anisotropic film containing 1 wt% Fe₃O₄ nanoparticles, an increase of 23.01% in film transparency was observed at the wavelength of 600 nm with a magnetic field of B = ~ 80 mT applied, which is 2.67 times greater than the maximum change achieved in our previous research. The variation in transparency caused by the external magnetic field has been tentatively assigned to magnetostrictive effect. And the film microtexture might have a great influence upon the way an external magnetic field alters film transmittance.