Evaluation of the efficiency of copolymers of methyl methacrylate and vinyl acetate synthesized by emulsion polymerization for control of aqueous filtrate loss

摘要

One of the main problems faced while drilling oil wells is loss of fluid to the rock formation. This loss can be reduced with the use of chemical additives called filtrate controllers, which must be tailored to the specific characteristics of the rock formation and drilling conditions. In this study, copolymers made of methyl methacrylate-co-vinyl acetate were synthesized by the emulsion polymerization technique, the most efficient technique to obtain copolymers with widely differing reactivity ratios. The products were characterized and evaluated for filtrate reduction efficiency, in the form of an emulsion and a polymer suspended in water. The filtrate reduction percentage, on the order of 80%, increased with higher concentration of vinyl acetate. The use of the polymer suspended in water caused only a slightly greater reduction in filtrate loss than that produced by the respective emulsion. However, other important advantages are associated with the suspended formulation: lower optimal concentration (approximate to 8.5 g/mL), formation of extremely discrete filter cake particles and better logistical aspects, since in the case of emulsions, the volume of material that must be transported is much greater. (c) 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42191.