Shear resistance performance of low elastic polymer microspheres used for conformance control treatment

Low elastic polymer microsphere (L-EPM) has been proposed as a functional polymer microsphere these years. L-EMP has the excellent deformation ability in the porous medium due to the low storage modulus. Herein, one kind of L-EPM with storage modulus (G′) of 23.6 Pa was prepared by inverse suspension polymerization . The shear resistance of L-EPM was researched by using core flooding experiment and high shear rate emulsifier. The conformance control behavior of L-EPM was investigated by using double parallel sandpack flooding experiment. The results showed that L-EPM was a kind of swollen particle gel with three-dimensional net structure and contained amide, carboxyl, and sulfonate groups. The mechanism of water swelling property was mainly due to the formation of hydrogen bonds, hydrolysis of hydrophilic groups and the diffusion caused by osmotic pressure difference. Compared with high elastic polymer microspheres (H-EPM) and low elastic preformed particle gel (L-PPG), L-EPM had better shear resistance in the porous medium and the well casing perforation. In addition, the critical shear points of L-EPM was proposed in this work. Due to the better shear resistance and deformation ability, the conformance control behavior of L-EPM showed that L-EPM was a promising conformance control agent in the heterogeneous reservoirs.