Synthesis Of Polymer Surfactants And Study Of Their Solution Properties

It is well-known that surfactants are molecules able to modify the surface properties of the liquid in which they are introduced(usually water). The simultaneous presence of both hydrophilic and hydrophobic parts in the same molecule has been recognized as the key feature of these systems, which is responsible for their characteristic properties in solution. A polymeric surfactant that combines the high viscosity of a polymer with the interfacial property of a conventional surfactant could reduce the tension at water/oil interfaces and enhance the viscosity of the aqueous solution simultaneously. Their properties make these polymers of potential interest for oil recovery.In the research, the molecular structure of a polymeric surfactant was designed based on polymer flooding which has excellent effect in enhancing oil recovery. Taking apparent viscosity as the technical index, we optimized the synthesis conditions of the polymeric surfactant. Under the optimal experimental conditions, sample of polymeric surfactants were obtained. Then the structure characterization of polymeric surfactant sample was conducted through IR,1HNMR and other modern analytical test methods. The results showed that the synthesized sample was the target product and its molecular weight was about 8.6×103 by the viscosity method and GPC measurement.The results of laboratory experiment indicated that polymeric surfactant can dissolve within 1 hour, so it has a better water-solubility than HPAM under the same condition. Viscosity of the polymeric surfactant aqueous solution reached 287 mPa.s when the mass concentration was 2000 mg/L, which means its tackifying effect was lower than that of HPAM. Compared with HPAM, polymeric surfactant aqueous solution viscosity was less affected by temperature and shear, but more influenced by salinity. Ring Method test illustrated that the surface tension of polymeric surfactant aqueous solution reached 44.30mN/m, so its surface tension was better than the common HPAM. However, the ability to reduce the oil/water interfacial tension was not good. Moreover, the heat resistance performance of polymeric surfactant was superior to that of HPAM.SEM study indicated that the hydrophobic segment of polymeric surfactant was able to form a tubular micelle at the mass concentration of 500mg/L and then constituted an aggregate of three-dimensional network structure. Physical simulation flooding experiments demonstrated that compared with HPAM, the polymeric surfactant would enhance oil recovery by more than 5%. Moreover, this approach should also have the advantage of avoiding the segregation into two phases that can occur in a flow stream for conventional polymer-surfactant mixtures. polymeric surfactant shows considerate application prospect in enhance oil recovery.