Fabrication and magnetorheology of bidisperse magnetic microspheres coated with gelatin and multi-walled carbon nanotubes. (12th November 2018)

• Record Type: Journal Article
• Authors: Fu, Yu; Yao, Jianjun; Zhao, Honghao; Zhao, Gang; Wan, Zhenshuai; Qiu, Ying
• Is Part Of: Smart materials and structures. Volume 27:Number 12(2018:Dec.)
• Publication Date: 2018-11-12
• Subjects: bidisperse magnetorheological fluids -- carbonyl iron -- gelatin -- multi-walled carbon nanotubes -- magnetic microspheres; Smart materials -- Periodicals; Strucural design -- Periodicals; 620.11
• DOI: 10.1088/1361-665X/aaeb79
• Languages: English
• ISSNs: 0964-1726

Abstract

Abstract: To improve the magnetorheological (MR) properties and dispersion stability of the carbonyl iron (CI) particles, bidisperse magnetorheological (BMR) fluids consisting of magnetic micron-sized CI and nanoparticles dual-coated with gelatin and multi-walled carbon nanotubes (MWCNTs) were synthesized for the first time. Gelatin was used as a grafting agent to improve the stability of bidisperse magnetic particles and restrict the oxidation of nanoparticles (Fe3 O4 ). And a dense network composed of MWCNTs on the surface of gelatin-coated bidisperse particles was fabricated based on the self-assembly of MWCNTs to produce considerably rough surfaces. The influence of functional dual-coated layer on rheological performance such as shear stress and yield stress behavior was investigated by a rotational rheometer upon various magnetic field applications. Additionally, the dispersion stability was measured through sedimentation tests. The results showed that CI–Fe3 O4 -Gelatin-MWCNTs (CI–Fe3 O4 –G–NT) magnetic microspheres possessed enhanced MR properties compared with those from CI–Fe3 O4 -Gelatin (CI–Fe3 O4 –G) microspheres, while the dispersion stability of CI–Fe3 O4 –G–NT microspheres was still maintained.