Abstract: The polyacrylic ester damping coating film of "core-shell" type IPN structure has been synthesized in this paper.The experiment methods including Gel Permeation Chromatograph(GPC),Different Scanning Calorimetry(DSC),Dynamic Mechanical Analysis(DMA) are used to predict the molecular weight,components and damping material property of IPN polymer.The IPN hydrosol of BA/MMA(soft core/hard shell) and MMA/BA(hard core/soft shell) are researched for comparison,but the latter is unstable and we choose the former.The rheology property of IPN hydrosol and water-solubilized coating are known by the rotational viscometer.The IPN hydrosol is newton fluid but the IPN water-solubilized coating is pesudo-plastical fluid.The IPN water-solubilized coating can been used well because of its thixotropy,and the coating film has excellent property after the determination.