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emulsifier

1. n. [Drilling Fluids]
A chemical additive that creates an emulsion, a dispersion of one immiscible liquid into another, by reducing the interfacial tension between the two liquids to achieve stability. Two emulsion types are used as muds: (1) oil-in-water (or direct) emulsion, known as an "emulsion mud" and (2) water-in-oil (or invert) emulsion, known as an "invert emulsion mud." The former is classified as a water-base mud and the latter as an oil-base mud.
Antonyms: demulsifier