Synthesis, characterization and magnetorheological study of 3-aminopropyltriethoxysilane-modified Fe₃O₄nanoparticles

Abstract

In this study, monodisperse Fe 3 O 4 nanoparticles were synthesized successfully using a sonochemical method in the presence of 3-aminopropyltriethoxysilane (APTES). The morphology, microstructure and magnetic properties of the bare Fe 3 O 4 and APTES-coated Fe 3 O 4 were investigated in detail by TEM, XRD, FTIR and SQUID. It was found that APTEScoated Fe 3 O 4 showed relatively gooddispersion with anarrow size distribution of 8.4±2.1 nmdiameter. The functionalization of Fe 3 O 4 was proved to be covalent linking between Fe 3 O 4 and APTES. The field-dependent magnetization curve indicated superparamagnetic behavior of Fe 3 O 4 -APTES with a saturation magnetization (M s ) of 70.5 emu g −1 at room temperature. Amagnetorheological (MR) fluid was prepared using the obtained Fe 3 O 4 -APTES nanoparticles with 25 wt% particles, and its MR properties weretested usinga Physica MCR301 rheometer fitted with an MRmodule. The results showed that the as-prepared APTES-coated Fe 3 O 4 nanoparticle-based MR fluid exhibited typical MR effects, with increasing viscosity, shear stress and yield stress depending on the applied magnetic field strength.

Investigation of sedimentation, rheological, and damping force characteristics of carbonyl iron magnetorheological fluid with/without additives

“…In contrast, column structures formed have not been broken, or the new aggregates have been re-arranged, which indicates the presence of large CIPs in the MR fluid. Similar observations have been reported by other workers [44][45][46][47][48].…”

APTES monolayer coverage on self-assembled magnetic nanospheres for controlled release of anticancer drug Nintedanib

“…2b may contain a stretching vibration of Fe-O-Si at 589 cm −1 overlaying with Fe-O vibrations from iron oxide 50 . The peak corresponding to Si-O-Si at 1015 cm −1 , and the bending and stretching vibrational modes of NH at 1637 cm −1 and 3400 cm −1 , respectively, confirm the coverage of silane with a free amine group of APTES on the MNS surface 58,59 . A band observed at 2920 cm −1 is due to C-H stretching vibrations of the anchored propyl group 60,61 .…”

Surface Modification of Magnetic Iron Oxide Nanoparticles

“…Wang et al adopted the sonochemical method to prepare the APTES-coated Fe 3 O 4 NPs with diameter 8.4 ± 2.1 nm and concluded that the synthesized NPs exhibited superparamagnetism and good dispersibility. Magneto-rheological fluids prepared on the basis of these IONPs have typical magneto-rheological properties [ 192 ]. Li et al developed acetylated APTES-coated Fe 3 O 4 NPs based on the hydrothermal method.…”