Aqueous Foam Stabilized by an in Situ Hydrophobic Polymer via Interaction with Alkyl Polyglycoside for Enhancing Oil Recovery

The stability of foams is a critical consideration given their numerous applications. Toward this effort, the hydrophobically associating water-soluble polymer (HAWP) was applied together with alkyl polyglucoside (APG) to form a highly stable foam system. The surface properties and aqueous properties were first investigated in HAWP/APG solutions, and then the specific characteristics created by HAWP were analyzed from the aspects of foam stability, coarsening behavior, and foam viscoelasticity, after which the possible self-assembly driving force between HAWP and APG was explored. The results indicated that the presence of HAWP in the APG foam causes the adsorption layer to change from being viscous to being elastic and produces a highly viscous force in the bulk phase. It was also found that the draining half-life of foam was increased up to six times and the coarsening behavior had reduced one order of magnitude as the polymer was involved. These observations were proved to be the formation of hydrogen bonding and hydrophobic force that resulted in a pronounced self-assembly driving force for forming the complex aggregations. Furthermore, the polymer-enhanced foam could successfully modify the oil–water front and substantially promote oil-displacement efficiency in porous media, which showed a great potential application in the oil recovery project.