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A smart magnetorheological elastomer peristaltic pump (MRE-PP) realizes controlled movements to convey Newtonian and non-Newtonian fluids under various scheduling policies for electromagnets. Although the structure of the basic element consisted of a magnetorheological elastomer tube and an electromagnet is very succinct, the capability of fluid conveying is dramatically improved when the magnetorheological elastomer peristaltic pump composed of more elements in series is employed. Besides, scheduling policies and the length of the magnetorheological elastomer tube, as another two significant factors, also have remarkable effects on backflow, pumped fluid volume, and viscosity of blood. Various scheduling policies are designed to realize fluid conveying with relatively high pumped volume for non-Newtonian fluid. Meanwhile, low destructiveness is demonstrated in the designed magnetorheological elastomer peristaltic pumps, allowing a potential application of conveying stress sensitive fluids.

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In this paper we designed greener rubber nanocomposites exhibiting high crosslinking density, and excellent mechanical and thermal properties, with a potential application in technical fields including high-strength and heat-resistance products. Herein 1-ethyl-3-methylimidazolium acetate ([EMIM]OAc) ionic liquid was combined with silane coupling agent to formulate the nanocomposites. The impact of [EMIM]OAc on silica dispersion in a nitrile rubber (NBR) matrix was investigated by a transmission electron microscope and scanning electron microscopy. The combined use of the ionic liquid and silane in an NBR/silica system facilitates the homogeneous dispersion of the silica volume fraction (φ) from 0.041 to 0.177 and enhances crosslinking density of the matrix up to three-fold in comparison with neat NBR, and also it is beneficial for solving the risks of alcohol emission and ignition during the rubber manufacturing. The introduction of ionic liquid greatly improves the mechanical strength (9.7 MPa) with respect to neat NBR vulcanizate, especially at high temperatures e.g., 100 °C. Furthermore, it impacts on rheological behaviors of the nanocomposites and tends to reduce energy dissipation for the vulcanizates under large amplitude dynamic shear deformation.

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A magnetorheological elastomer peristaltic fluid conveying system consisting of a magnetorheological elastomer tube and two electromagnets implements controlled movements via an external magnetic field with varying periods of driving voltages to convey non-Newtonian fluids over a certain time period. The effects of backpressure at the outlet of the magnetorheological elastomer peristaltic fluid conveying system, the viscosity of fluids at zero shear rate, and moisture loss along the longitudinal direction on net pumped volume are investigated systematically. The results demonstrate that the net pumped volume declines linearly with backpressure under all driving voltage periods. An improvement of the viscosity of fluids at zero shear rate allows at first the decrease, then the increase, and finally the decrease of the net pumped volume. Moisture loss plays a second role in the net pumped volume and the change of the fluid viscosity profile. The compression of the magnetorheological elastomer tube, the maximum shear stress, and the maximum von Mises stress in the magnetorheological elastomer peristaltic fluid conveying system are investigated to evaluate the magneto-fluid-structure interaction. This research offers a new approach to biological fluid conveying with an analogic moisture loss process.