摘要 |
<p>The invention relates to a process for preparing a polymer whose molecular mass and anionicity degree are especially established for temperatures of up to 110A C and a ionic content of formation water ranging from a very low to a very high level (TDS=0.06...30 g%), to be used in gelation systems to modify the permeability profile of oil fields. The synthesis of the acrylic polymer is based on the copolymerization rection between acrylamide and sodium acrylate, in an aqueous solution, at a concentration of 6...10% For adjusting the molecular mass, a disodic salt of the ethylenediaminotetra-acetic acid is admixed. As initiating agents there is employed the potassium persulphate/sodium sulphite redox system or thermolabile organic initiating agents. With a view to increasing the resistance to temperatures of up to 110A C and salinities of up to 30 g%, potassium iodide is admixed. The R-type copolymer is presented as an aqueous solution having 7...10% active substance, a molecular mass of 0.8...2.2x10^6 g/mole, KH=0.5...0.55, an anionicity degree of 6...12% and pH=5.5...7.</p> |