Evaluation and improvement of swelling characteristics of gel used for profile control

In view of the technical limitations of ordinary polyacrylamide hydrogel revealed gradually in the chemical profile control, a research was conducted on water soaking and viscosity loss of chrome crosslinking system and phenolic resin crosslinking system within a temperature range of 50 ℃ to 90 ℃; and following the basic theory of Darcy’s Law, a new soluble polymer material was introduced to improve the strength of ordinary gel crosslinking strength starting from increasing the crosslinking density and reducing gel swelling degree. The results show that, when gel is adequately soaked in water, its viscosity will decrease with the extension of reaction time, and that the gel has swelling function and its viscosity loses. Addition of PVA can easily create in-grid hydrogen bond or winding with polyacrylamide molecules, which plays the role of physical crosslinking point and improves the gel viscosity by 30%. After observation for 180 days, its viscosity loss is less than10%. The research results can provide technical support for solving interlayer contradictions and initiating the production potential of low-permeability sections.