Effect of magnetic field on the rheological properties of poly(ethylene glycol) and poly(dimethylsiloxane) mixtures with aerosil and iron nanoparticles

The effect of a magnetic field on the viscosity of magnetorheological poly(ethylene glycol)-aerosil-iron nanoparticle and poly(dimethylsiloxane)-aerosil-iron nanoparticle suspensions is studied. The magnetic field leads to an increase in the viscosity of the suspensions by a factor of 20–300. The concentration dependence of the effect of magnetic field on the viscosity of the systems is described by a curve with a maximum. The dependences of viscosity on shear rate upon loading and unloading do not coincide, thus indicating the relaxation character of the flow process.