Preparation and characterization of polyacrylamide nanomicrospheres and its profile control and flooding performance

Abstract In this study, a new profile control and flooding agent “polyacrylamide nanomicrospheres” with particle size of 120–180 nm was prepared by inverse microemulsion polymerization. The viscoelasticity of polyacrylamide nanomicrospheres and the swelling property of polyacrylamide nanomicrospheres in aqueous solution were characterized. Using sand pack models, the profile control and flooding performance of polyacrylamide nanomicrospheres was studied. The results show that the polyacrylamide nanomicrospheres have better elasticity; the polyacrylamide nanomicrospheres have obvious swelling property, which depends on the concentration of NaCl and temperature; the polyacrylamide nanomicrospheres can plug sand pack effectively and have better ability of transporting and plugging in porous media; the polyacrylamide nanomicrospheres prefer to plug high permeability layer selectively so as to increase the swept volume and enhance oil recovery of low permeability layer and low permeability area in high permeability layer; the polyacrylamide nanomicrospheres can enhance oil recovery by 11–14%. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013