| abstract |
A suspension, for use as an oilfield fluid, is composed of at least one ethylene vinyl acetate copolymer, at least one surface active agent other than an ethylene vinyl acetate copolymer and a bipolar solvent. The bipolar organic solvent has a boiling point higher than the melting point of the ethylene vinyl acetate copolymer. The polar and nonpolar groups of the bipolar organic solvent and the ethylene vinyl acetate copolymer(s) form a micellar self-assembly such that the polar groups and nonpolar groups of the ethylene vinyl acetate copolymer(s) are associated with the polar groups and nonpolar groups, respectively, of the bipolar organic solvent. The micellar self-assembly serves as a vehicle for the incorporation of the surface active agent(s) into a single multi-component blend. Suitable surface active agents include corrosion inhibitors, scale preventatives, demulfisying agents, paraffin inhibitors, gas hydrate inhibitors, flocculanting agents as well as asphaltene dispersants. The suspensions are prepared by heating and mixing a mixture comprising the surface active agents, ethylene vinyl acetate copolymer(s), and bipolar organic solvent to a temperature sufficient to solvate the ethylene vinyl acetate copolymer(s), preferably from about 280 to about 375° F. The product is then air cooled such that the ethylene vinyl acetate copolymer(s) are excluded to form the suspension. |