Akademik Veri Yönetim Sistemi
European Polymer Journal, cilt.208, 2024 (SCI-Expanded)
Phosphonium-based poly(ionic liquid) (PPIL) as well as its nanocomposites with halloysite (HNT) and graphene oxide (GO) were synthesized in this study. PPIL structure was engineered to be poly[(4-vinylbenzyl) trimethyl phosphonium trifluoromethane sulfonate] for high electrorheological (ER) performance. To improve ER properties of PPIL, HNT clay with strong mechanical, thermal, and insulating properties and GO with strong dielectric properties were introduced into the PPIL structure by covalent bonding. The synergistic electroactive effect of HNT and GO in the hybrid nanocomposites were investigated by comparing PPIL, HNT/PPIL and HNT/GO/PPIL structures. Structural, thermal, and morphological characterizations approved the successful synthesis of samples. Dielectric and ER flow tests of dispersions of the engineered structures in insulating silicone oil (SO) indicated that PPIL (Δε′ = 1.80 and τy = 250 Pa, EReff = 35, G′ = 33 kPa at 2.0 kV mm-1) and HNT/PPIL (Δε′ = 1.55 and τy = 260 Pa, EReff = 51, G′ = 100 kPa at 2.0 kV mm-1) have similar electroactive properties whereas the highest polarizability and ER response are achieved with HNT/GO/PPIL hybrid nanocomposite (Δε′ = 2.50 and τy = 410 Pa, EReff = 67, G′ = 790 kPa at 2.0 kV mm-1). The findings indicated that electrical stability and electric field induced polarizability of PPIL have been improved by the presence of HNT and GO, respectively. When compared with the previously reported ER studies for ammonium-based poly(ionic liquid)s, PPIL and its nanocomposites of HNT/PPIL and HNT/GO/PPIL exhibited better ER properties, as projected. The application of electric field resulted in the switchable viscoelastic character for PPIL/SO, HNT/PPIL/SO and HNT/GO/PPIL/SO dispersions. Similar to the ER flow properties, the best electroactive viscoelastic properties were obtained for the dispersion of triple HNT/GO/PPIL hybrid nanocomposite. Overall, new ER dispersions of phosphonium-based poly(ionic liquid) and its superior nanocomposites were introduced to the literature.