Rheological investigation of a random copolymer of polyacrylamide and polyacryloyl hydrazide (PAM-ran-PAH) for oil recovery applications

In this article, we synthesize and investigate the rheological properties of a random copolymer PAM-ran-PAH of polyacrylamide (PAM) and polyacryloyl hydrazide (PAH) and compare with the results of PAM at different temperature (30 and 80 °C) and salinity (0 and 1.0 wt %). At 30 °C, both PAM and PAM-ran-PAH exhibited non-Newtonian rheology with both shear thinning and shear thickening responses. The rheological properties such as viscosity and moduli (G′ and G″) of PAM significantly deformed at elevated temperature (80 °C) and salinity (1.0 wt %), resulting no recovery in viscosity and moduli. On the other hand, the effect of temperature and salinity was found to be least on PAM-ran-PAH and showed better stability with the possibility of recovering its original rheological properties. The performance of PAM and PAM-ran-PAH was also characterized by enhanced oil recovery tests. The use of PAM-ran-PAH for polymer flooding, due to its stable rheology, resulted in an increase in the oil recovery than PAM. In general, the rheological behavior of PAM-ran-PAH as a chemical agent proved to be thermally stable than PAM, which clearly supports its use for saline environment and high temperature applications. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44648.