Lu Q, Lee JH, Lee JH, Choi HJ. Magnetite/Poly(ortho-anisidine) Composite Particles and Their Electrorheological Response.
MATERIALS (BASEL, SWITZERLAND) 2021;
14:2900. [PMID:
34071366 PMCID:
PMC8198630 DOI:
10.3390/ma14112900]
[Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 05/23/2021] [Accepted: 05/26/2021] [Indexed: 11/30/2022]
Abstract
Magnetic and semiconducting Fe3O4/poly(o-anisidine) (POA) core/shell composite particles were fabricated by an oxidation process using Fe3O4 synthesized separately. The dispersion stability in a liquid medium and the electrical conductivity of synthesized particles were improved because of the conductive POA polymeric shell. The morphological, microstructural, compositional/elemental, and thermal behaviors of the particles were characterized using SEM with energy dispersive X-ray spectroscopy, TEM, XRD, and thermogravimetric analysis, respectively. A smart electro-magneto-rheological suspension containing Fe3O4/POA particles with two functionalities, magnetism and conductivity, was prepared. Its electrorheological properties were investigated at different electric field strengths using a rotational rheometer. Without an electric field, the sample demonstrated typical Newtonian fluid behavior, as expected. However, while under the electric field, it exhibited a solid-like behavior, and the dynamic (or elastic) yield stress of the ER fluid increased linearly as a function of the electric field strength in a power-law function with an index of 2.0, following the polarization mechanism.
Collapse