Akademik Veri Yönetim Sistemi
Journal of Molecular Liquids, cilt.446, 2026 (SCI-Expanded, Scopus)
Electrorheological (ER) fluids are stimuli-responsive smart materials that comprise electrically polarizable particles dispersed in an insulating liquid, exhibiting rheological behavior that is electric-field-dependent and reversible. Due to its outstanding properties, such as one-dimensional (1D) fibrous morphology, porosity, high aspect ratio, and large surface area, sepiolite possesses advantage of displaying a stronger electric field response and improved dispersion stability. Its unique crystal structure and strong secondary interactions among fibers lead sepiolite to be tightly packed as bundles of fibrous nanostructures. However, adequate disaggregation of sepiolite bundles into individual fibers is required to utilize the properties of sepiolite at a high level. In this study, various processes, including purification, lyophilization, and mechanical grinding, were applied to raw sepiolite to ensure the disaggregation of sepiolite fibers and improve porosity through a simple physical process, prior to preparing sepiolite-based ER fluids. The structural, morphological, dielectric, and dispersion stability properties of treated sepiolite samples were characterized by various techniques. The effects of the applied processes on the ER performance of the sepiolite dispersions prepared in polydimethylsiloxane were investigated via steady and oscillatory shear tests. The strongest yield stress (400 Pa at 2.5 kV/mm), excellent dispersion stability (97 % at the end of 25 days), and faster and stronger interfacial polarization were achieved in purified and following lyophilized sepiolite dispersion with 10 wt% particle concentration, while the mechanical grinding process caused adverse effects on the ER response, dispersion stability, and dielectric properties of sepiolite dispersion. Such basic physical approaches can be considered to achieve improved ER performance in future studies on 1D nanostructure-based ER fluids.