Abstract

Dispersants are compounds that are used to maintain particles suspended in a liquid medium, either water or an organic solvent. They can prevent or delay flocculation of the particles by providing repulsive forces, counteracting the van der Waals attraction. This attraction occurs through electrostatic or steric stabilization or through a combination of these mechanisms, electrosteric stabilization.

Unlike classical dispersants, which are usually random polymers, modern dispersants consist of an anchoring section, which adheres to the particle surface, and a soluble section, which builds a protective shell around the particle. They can have different architectures: AB dispersants, AB-diblock polymers, ABA- or ABC-triblock polymers, and comb polymers. Syntheses of such architectures are discussed.

Dispersants have some similarity, but also some clear differences, with other materials, like surfactants, chelants, precipitation inhibitors, and flocculants.

Dispersants have numerous applications. They are used, among others, in cooling and heating water applications, in geothermal fluids, seawater distillation and reverse osmosis, in oilfield and mineral processing, in cements, asphalt, caulks, sealants and roof coatings, in detergents and cleaners, and in paints and printing inks.