Rheological properties of silicon oil-based magnetic fluid with magnetic nanoparticles (MNPs)-multiwalled carbon nanotube (MWNT)

Abstract

In order to research the influence of multiwalled carbon nanotube (MWNT) on the rheological properties of magnetic fluid, silicon oil-based magnetic fluid with or without MWNT was prepared in the present investigation. Magnetic nanoparticles (MNPs) were synthesized by chemical coprecipitation with a certain amount of MWNT (0, 0.5 wt%). Then, Siliane coupling agents N-(2-aminoethyl)-3-aminopropyltrimethoxysilane was used to modify the MNPs. The morphologies, microstructures and magnetic properties of the particles were characterized by transmission electron microscopy, fourier transform infrared spectroscopy and vibrating sample magnetometer. The effect of MWNT on rheological properties was investigated by the rotational rheometer, such as viscosity-temperature, viscosity-magnetism. Therefore, the results showed that the addition of MWNT significantly increases the viscosity of the magnetic fluid, and the viscosity increases with the magnetic field strength and decreases with increasing temperature. In addition, the shear stress increases with increasing shear rate, while the viscosity decreases with increasing shear rate. The rheological properties of magnetic fluid with or without MWNT are consistent.