Preparation method for emulsion polymer macro-molecular strong coating agent

Abstract

The invention provides a preparation method for an emulsion polymer macro-molecular strong coating agent used for drilling fluid. The method comprises the following steps: mixing potassium hydroxide, acrylic acid and acrylamide with deionized water so as to obtain a first solution; mixing surfactant with an oil-soluble solvent so as to obtain a second solution; and filtering the first solution with active carbon, then adding the first solution into the second solution drop by drop and adding the aqueous solution of an initiator into the second solution for a copolymerization reaction so as to obtain the emulsion macro-molecular strong coating agent. According to the invention, preparation process is simple and easily controllable; a fast polymerization speed is obtained due to usage of an inverse emulsion polymerization method; obtained macro-molecular emulsion is stable and does not undergo delamination when stored for a long time; and the product of the coating agent has good lubrication performance, can be easily dissolved in drilling fluid and has strong capacity in inhibiting dispersity.

Description

technical field [0001] The invention relates to the field of polymer synthesis, in particular to a preparation method of an emulsion polymer macromolecular strong coating agent for drilling fluid. technical background [0002] Most of the traditionally used polymers for drilling fluids in oil drilling are powdery, and the molecular weight is not high or allowed to be too high. The reason is that if the molecular weight is too high, it will be difficult for the treatment agent to dissolve, and a part of it will float in the well. On the surface of the liquid tank, agglomerates that are almost no longer dissolved form each other. Part of the drilling fluid is mixed with the drilling fluid and is removed by the solid control equipment before it can be completely dissolved. ; Therefore, the molecular weight of polymers used in most domestic drilling fluids is between 3 million and 5 million, and such low molecular weight polymers are difficult to achieve strong inhibition. Con...

AI Technical Summary

Problems solved by technology

[0003] In order to overcome the disadvantages of the existing polymers used in drilling fluids, which are difficult to dissolve and weak in restraint, the invention provides a method for preparing a strong coating agent for emulsion polymer macromolecules in drilling fluids. The prepared emulsion polymer macromolecules The molecular weight of the strong coating agent is as high as 6 million to 12 million. It has the advantages of long maintenance period, strong inhibition and dispersion, high viscosity and sand carrying ability, fast dissolution speed and good lubricating performance in the mud system.