Abstract:

The rheological properties of nanometer SiO₂′s dispersion system under the conditions of different dispersion me-diums, as well as the different relative molecular mass and temperature of one single dispersion medium were determined and compared.The results showed that with the increasing of the relative molecular mass,the dispersion system′s viscosity increa-sed,the hydrogen bonding between solid and liquid weakened and the critical shear stress needed by dispersion system dec-reased.When the relative molecular mass of dispersion medium increased to some extent,the hydrogen bonding between solid and liquid was weaker and space steric effect was caused by the growth of molecular chain.Then the nanometer SiO₂ was not exis-tent with three-dimensional netted structure in dispersion medium,the rheological properties curves didn′t have shear thinn-ing first and then shear thickening.With the increasing of the dispersion medium′s temperature,the dispersion system′s viscosity decreased,the critical shear stress for shear thickening increased,the effect of the shear thickening became worse,and even the rheological properties curves didn′t have shear thinning first and then shear thickening.So selecting suitable dispersion medium and dispersion medium′s temperature can improve the rheological properties of nanometer SiO₂′s dispersion system.

Key words: nanometer SiO₂, shear thickening fluid, dispersion system, rheological properties, dispersion medium