The Synthesis And Evaluation Of Hydrophobic Association Thickener

With the development of oil and gas in oil field, most of the oil field have alreadyentered the late stage of exploitation in our country. Low permeability reservoir has beendeveloped in pursuit of production. Oilfield faces that the formation permeability is low, thequantity of produced fluid in oil wells is little, the injection pressure in water wells is large,etc. Hydraulic fracturing is a very effective stimulation method for oil and water wells. Theperformance of fracturing fluid is directly related to the quality of the fracturing. Specialperformance of fracturing fluid is mainly on the performance of the fracturing fluid thickener.The paper provides a new hydrophobic association polymer fracturing fluid gelatinizer.The hydrophobic association which is the synthesis of three component copolymercomplexes, is compound by micellar copolymerization method. The hydrophobic associationis got together through hydrophilic monomer acrylamide monomer N,N-vinyl pyrrolidonemonomer with a rigid group N, and hydrophobic monomer N, N-2dodecyl acrylamide etcthree monomers with sodium dodecyl sulfate as the emulsifier in micellar solution.The hydrophobic association synthesized by micellar copolymerization method isembedded hydrophobic association, which has the hydrophobic effect. Vinyl pyrrolidone witha rigid group N has steric-hinerance effect, which can improve the heat resistance and saltresistance of associated content. N,N-2dodecyl acrylamide is a twin tail hydrophobicmonomer which has more hydrophobic density and association ability. The components ofhydrophobic groups do not change with the change of the percent conversion in the processof polymerization reaction.The hydrophobic association has hydrophobic groups, which can occur association inwater solution. When concentration is higher than the critical concentration of hydrophobicassociation (C*), associating things can happen intermolecular association. The association iscomplex to form a three-dimensional network structure, form a super large molecules, andaffect the rheological properties of solution. The association is a physical effect and reversible,which means mesh structure can give recovery after shear failure, and it has shear thinning,shear resistance and shear resistance resilience.Experiment shows that when the hydrophobic association compounds with sodiumdodecyl benzene sulfonate surface active agent,it will form a special structure, which hashigher viscosity and viscoelasticity. The complex fracturing fluid withhydrophobicassociation and surface active agent has temperature resistance and salt resistance. When thetemperature is up to90℃, the simulated formation water still has high viscosity, it can meet the requirements of fracturing with complete gum breaking, high discharge rate and lessdamage to the bottom.