![](/views/old_jom/img/center_up.gif)
Search
![](/views/old_jom/img/dot2.gif)
Polyindole-Coated Soft-Magnetic Particles and their Viscoelastic Behaviors under Applied Magnetic Field
Journal of Magnetics, Volume 24, Number 1, 31 Mar 2019, Pages 155-161
Abstract
To solve the sedimentation drawback of soft-magnetic carbonyl-iron (CI) particles for their application to a magneto-rheological (MR) fluid, the coating of a polyindole (PIn) onto the surfaces of CI microspheres was
introduced through chemical oxidization polymerization using 4-aminobenzoic acid as a grafting chemical to increase the interaction between CI particles and PIn. The coated morphology was confirmed using a scanning
electron microscope, whereas the reduced density was examined through a gas pycnometer. The effect of the coating on MR performance was analyzed using a rotation rheometer connected with a magnetic field generator. Based on the results of a dynamic oscillation rheological test, the CI/PIn-based MR fluid exhibited a more elastically solid behavior with the applied magnetic fields when compared to a pure CI-based MR suspension, showing an increased magnetic-field strength-dependent storage modulus from a strain sweep test. With a solid-like behavior under an applied external magnetic field, the storage modulus was observed to be higher than the loss modulus within the entire frequency range.
introduced through chemical oxidization polymerization using 4-aminobenzoic acid as a grafting chemical to increase the interaction between CI particles and PIn. The coated morphology was confirmed using a scanning
electron microscope, whereas the reduced density was examined through a gas pycnometer. The effect of the coating on MR performance was analyzed using a rotation rheometer connected with a magnetic field generator. Based on the results of a dynamic oscillation rheological test, the CI/PIn-based MR fluid exhibited a more elastically solid behavior with the applied magnetic fields when compared to a pure CI-based MR suspension, showing an increased magnetic-field strength-dependent storage modulus from a strain sweep test. With a solid-like behavior under an applied external magnetic field, the storage modulus was observed to be higher than the loss modulus within the entire frequency range.
Keywords: polyindole; carbonyl iron; core-shell; magnetorheological
DOI: https://doi.org/10.4283/JMAG.2019.24.1.155
Full Text : PDF
![](/views/old_jom/img/center_down.gif)