Preparation Of Core-shell Profile Control Agent With The Shell Of P(AM+EHA)

In the oil extraction process, large pore path was produced in reservior due to along time of scouring, clay swelling, and particle migration. Oilfields have basicallyentered the high water-cut or extra-high water-cut production stage. Therefore, it issignificant to developa new profile control agent which can effectively block largepore and has a good profile control performance in the high temperature, highalkalinity and high salinity reservoir.As P(AM+EHA) has the capability of profile control, it has been used as shellmaterial to prepare three kinds of core-shell structure composite profile controlagent.The particle morphology, core-shell structure and composition of compositematerial were characterizedby SEM, dynamic light scattering, TEM, FTIR, EDS.What’s more, density of particles, solid content, heat resistance, alkali resistance,salt resistance and other properties were analyzed and evaluated.CS/P(AM+EHA), thelarge particleof core-shell structure composite profilecontrol agent was prepared by suspension. This method caneffectivelysynthesiscore-shell structure composite particles with the size up todozens of micrometers and overcome the shortcoming, that is to say, emulsionpolymerization cannot make incompatible monomer copolymerization. The averagedensity of profile control agent particles is close to the density of injected water; themaximum sedimentation rate ofsuspenedparticleis5.6mL/min, the sedimentationratio is72%;This composite had a good profile control performance used in hightemperature and high salinity reservoir.PAA/P(AM+EHA), the swellable type of core-shell structure composite profilecontrol agent was prepared using inverse emulsion polymerization. The density ofthe profile control agent particles is close to the density of injected water; compositesolid content is above85%; volume expansion ratio is above100%, waterabsorption time up to20min can achieve maximum expansion volume; Thiscomposite had a good profile control performance used in high temperature, highsalinity and alkaline reservoir.P(AM+AA)/P(AM+EHA), the swellable type of core-shell structurecompositeprofile control agent was prepared using inverse emulsion polymerization.The density of the profile control agent particles is close to the density of injectedwater; composite solid content up to90%; volume expansion ratio is above300%,water absorption time up to30min can achieve maximum expansion volume; Thiscomposite had a good profile control performance used in high temperature, highsalinity and alkaline reservoir.