One of the traditional ways for the enhanced oil recovery is the usage of flow-diverting technologies with polymer solutions as process fluids with a high viscosity. Among such polymers, various copolymers based on the acrylamide and acrylic acid can be called main. The diversity of the chemical composition of polyacrylamides leads to a difference in the technological properties, thus, the correctness of the polymer choice has a significant impact on the effectiveness of specific flow-diverting technologies. Mainly, the quality control of the polyacrylamides is carried out according to known standard methods, but in some cases the standard methods are not suitable to obtaining the reliable information about the studied object. The same time, spectral analysis methods have great analytical capabilities for polymers studying. It was shown that the Fourier-Transform Infrared (FT-IR) spectroscopy technique allows distinguishing from each other the anionic hydrolyzed, anionic sulfonated, cationic and non-ionic polyacrylamide. Important feature is that the Attenuated Total Reflection technique allows making analysis of samples in a solid state without complicated sample preparation. It was also shown that a FT-IR study of the residue after evaporation of a liquid makes it possible to identify the type of polyacrylamide in a solution. The other possibility was discovered while study of a numerous polyacrylamide samples. It was shown that combination of a FT-IR spectroscopy and X-ray spectroscopy techniques allows identifying the various organic and inorganic impurities in polyacrylamide samples. In particular, some of the samples studied were found to contain the citric acid, sodium chloride, sodium sulfate and ammonium sulfate. The presence of impurities in the polyacrylamide samples makes the results of the gravimetric analysis and potentiometric titration unreliable. Therefore, studying of such samples with standard methods will give false results. Thus, the obtained data allow us to recommend the spectroscopic analysis techniques as an addition to the existing quality control methods for chemical reagents.
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