Solvent Dependence of the Rheological Properties in Hydrogel Magnetorheological Plastomer

Chemically crosslinked hydrogel magnetorheological (MR) plastomer (MRP) embeddedwith carbonyl iron particles (CIPs) exhibits excellent magnetic performance (MR effect) in thepresence of external stimuli especially magnetic field. However, oxidation and desiccation inhydrogel MRP due to a large amount of water content as a dispersing phase would limit its usagefor long‐term applications, especially in industrial engineering. In this study, different solvents suchas dimethyl sulfoxide (DMSO) are also used to prepare polyvinyl alcohol (PVA) hydrogel MRP.Thus, to understand the dynamic viscoelastic properties of hydrogel MRP, three different sampleswith different solvents: water, DMSO, and their binary mixtures (DMSO/water) were prepared andsystematically carried out using the oscillatory shear. The outcomes demonstrate that the PVAhydrogel MRP prepared from precursor gel with water shows the highest MR effect of 15,544%among the PVA hydrogel MRPs. However, the samples exhibit less stability and tend to oxidiseafter a month. Meanwhile, the samples with binary mixtures (DMSO/water) show an acceptable MReffect of 11,024% with good stability and no CIPs oxidation. Otherwise, the sample with DMSO hasthe lowest MR effect of 7049% and less stable compared to the binary solvent samples. This confirmsthat the utilisation of DMSO as a new solvent affects the rheological properties and stability of thesamples.