Preparation And Rheological Benavior Of Functionalized Ionic Liquid-Based Shear Thickeing Fluids

Shear thickening fluid?STF?is a type of energy-consuming material whose viscosity increases with increasing shear rate.Shear thickening fluids usually consist of a dispersed phase and a dispersion medium.The dispersing medium has the disadvantage of poor temperature adaptation and the inability to configure high-concentration dispersions.However,ionic liquids can overcome these shortcomings,and can be used as a dispersion medium for shear thickening liquids.In this paper,the functionalized ionic liquid is used as the dispersion medium,and the silica nanoparticles are used as the dispersed phase to study the rheological properties of the shear thickening liquid.?1?Firstly,ionic liquids with different ionic structures as the dispersion medium,and the influence of the ionic structure on the thickening performance is studied.The results show that ionic liquids with hydroxyl groups are more likely to thicken.The effect of temperature on the rheological properties of the shear thickening liquid was also studied.The thickening effect of STF is more obvious at low temperatures.As the temperature increases,the viscosity of the ionic liquid decreases and the thickening effect weakens.?2?The ionic liquid was used to modify the silica in different ways to change the nanoparticle surface.The effect of SiO₂ with different chemical composition on its rheological and reversible properties was studied.The results show that the particles with tetrafluoroborate ions on the surface have increased thickening effect.?3?We expore the effect of adding microcrystalline cellulose on rheological properties of shear thickening fluid.Pretreatment of cellulose with DMF exposes more hydroxyl groups,and configures a shear thickening solution with different amounts of cellulose.The results show that after adding less cellulose,the thickening effect is increased.