1. n. [Drilling Fluids]

A thinning agent used to reduce viscosity or prevent flocculation; incorrectly called a "dispersant." Most deflocculants are low-molecular-weight anionic polymers that neutralize positive charges on clay edges. Examples include polyphosphates, lignosulfonates, quebracho, and various water-soluble synthetic polymers.

Synonyms: thinner

Antonyms: flocculant

See: acrylamide polymer,  acrylate polymer,  Bingham plastic model,  bland coring fluid,  carbonate ion,  chrome lignosulfonate,  chrome-free,  clay-water interaction,  conventional mud,  deflocculated mud,  direct-indicating viscometer,  drill solids,  gel strength,  gyp mud,  kill-weight fluid,  lignin,  lignite,  lignosulfonate,  phosphate salt,  plastic viscosity,  polar compound,  polymer,  red mud,  rheology,  SAPP,  sulfonated polystyrene-maleic anhydride copolymer,  tannic acid,  tannin,  yield point