Hydrophobically Associating Water-soluble Polymers In Porous Media Association

Hydrophobically associating polymer, a sort of water-soluble polymer, comparatively fits for oil-field development. Under CAC, it can occur intramolecular association, above CAC, it will occur intermolecular association, thus resulting in "structure" and forming "dynamically physical cross-linked network structure". At the same time, supermolecular structure comes into being, and the viscosity of polymer solution increases greatly. On shearing, the dynamically physical cross-linked network structure can be destroyed, and polymer solution exhibits typically pseudo-plastic behavior; physical cross-linked network structure of the macromolecule reforms with decreasingly shearing intension, and polymer solution viscosity restored again, thus reflects that Hydrophobically associating polymer has its unique characteristics to resist warming up, salt, and shearing.Intergranular flowing velocity and resistance factor were employed in this paper to study on whether associating behaviours exists and the factors influencing on associating behaviours in porous media. The following are the main contents and conclusions in this paper:Firstly, optimized polymer AP-P3 is a kind of hydrophobically associating polymer. Its critical associating concentration (CAC) was 1000mg/l at 60 and 5309.74mg/l salinity.Secondly, AP-P3's rheological properties in lab indicated that it has the obvious characteristics of hydrophobically associating polymer. That is, the viscosity of polymer solution sharply increased with increasingly polymer solution concentration above CAC, At the same time, the characteristics of shearing thinning and shearing resistance exhibited, too.Thirdly, the rheological properties of polymer in 60 and l0MPa indicated that the viscosity of the hydrophobically associating polymer solution consists of two parts when the concentration is above CAC. That is, Fourthly, the study on associating behaviors of hydrophobically associating polymer in the porous media indicated that associating behavior occurred obviously.Fifthly, concentration of the hydrophobically associating polymer and porous media size were major factors influencing on associatng behaviors in porous media.Lastly, coreflowing experiments results indicated that solution molecule of the polymer occurs intermolecular association, above CAC, forms structure viscidity, which decreases action of shear degradation and thinning in porous media. That has maintained the viscidity of the polymer solution and strengthened the result of raising the viscidity of water in the porous medium.