Investigation of the crosslinking process of polymer materials to enchance the efficiency of waterproofing compounds

Background: Currently, a significant portion of the oil fields in Kazakhstan are at the final stages of development, characterised by a steady decline in oil production and a progressive increase in water cut. These processes greatly diminish the efficiency of reservoir operation and make managing hydrocarbon displacement systems more complex. Under current conditions, technologies aimed at limiting and isolating water inflows are becoming increasingly relevant as a key element in enhancing the efficiency of field development. One promising approach in this area is the use of gel-polymer systems capable of selectively blocking highly permeable, water-saturated zones and redirecting filtration flows toward oil-saturated intervals. This allows for a significant increase in oil recovery and improves the technical and economic performance of reservoir development. Aim: The study aims to investigate the cross-linking process of polymer gels and to evaluate the key parameters of this process using various methods. Materials and methods: Special attention has been paid to the development and implementation of a rheological method for accurate quantitative determination of gel cross-linking time, which significantly enhances the objectivity and reproducibility of results compared to traditional visual assessment, which is currently the only generally accepted method. Results: It has been established that visually complete crosslinking occurs in 1.5–2 hours after the preparation of solutions. At the same time, rheometric measurements showed that crosslinking occurred significantly earlier. This confirms the higher accuracy and sensitivity of the instrumental method. Conclusion: The studies confirmed that rheometric methods allow high-precision determination of the time and degree of polymer crosslinking, which is impossible with visual assessment. This provides operators with more reliable information about the gel structure formation process and allows them to control the key parameters of gel formation at early stages. The data obtained emphasise the importance of rheometry as a reliable tool for objective evaluation of polymer crosslinking. Such evaluation plays a crucial role in the design and implementation of gel-polymer systems in oil recovery enhancement technology, especially in conditions of complicated geology and high water cut.