Classification of dispersants
As far as dispersants are concerned, according to their chemical composition, they can be roughly divided into two categories: inorganic dispersants and organic dispersants.
Inorganic Dispersants
Inorganic dispersants represent a class of compounds that do not have carbon-hydrogen (C-H) bonds within their molecular framework. This category typically includes metal-containing compounds or salts, such as sodium, potassium or ammonium compounds. Notable examples include sodium polyphosphate, sodium hexametaphosphate, and various metal hydroxides. In applications such as ceramics, inorganic dispersants play a vital role by helping to disperse ceramic particles in a liquid medium during processing. Their inherent properties make them suitable for specific industrial processes where inorganic chemistry plays a key role.
Organic dispersants
Organic dispersants, on the other hand, comprise compounds characterized by the presence of carbon-hydrogen (C-H) bonds in their molecular structure. This diverse category includes a wide range of substances, including surfactants and polymeric dispersants. Examples of organic dispersants cover various surfactant classes, such as nonionic, anionic, cationic or amphoteric surfactants. In addition, polymeric dispersants based on polymers having functional groups such as carboxylates, sulfonates, or amines are part of the group. Organic dispersants are used in a wide variety of industries, including paints, inks, coatings, environmental remediation and agrochemicals. Their versatility stems from their ability to stabilize dispersions, prevent particle agglomeration, and help improve the overall efficacy of numerous formulations in complex processes.
The choice between inorganic and organic dispersants depends on factors such as the nature of the particles being dispersed, the nature of the liquid medium and the specific requirements of the application. Both types of dispersants have their unique advantages and are selected based on the desired outcome of the formulation process.
Examples of Organic Dispersants
Organic dispersants include a wide variety of compounds that are characterized by the presence of carbon-hydrogen (C-H) bonds in their molecular structure. These dispersants are critical in a variety of industries for processes such as stabilizing dispersions, preventing particle agglomeration, and facilitating pigment dispersion in coatings and inks. Different types of organic dispersants include:
Surfactants
Surfactants or surfactants are a broad class of organic dispersants with hydrophilic (water absorbing) and hydrophobic (water repelling) components. Surfactants act as dispersants by lowering the surface tension between the particles and the liquid medium, resulting in effective dispersion. They are categorized into different types based on the nature of hydrophilic or hydrophobic groups:
Anionic surfactants: contain negatively charged hydrophilic groups and are commonly found in soaps and detergents.
Cationic surfactants: have positively charged hydrophilic groups and are commonly used in fabric softeners and antimicrobial agents.
Nonionic surfactants: lack charged groups, versatile and widely used, including emulsifiers and stabilizers.
Amphoteric surfactants: contain both positively and negatively charged groups, providing versatility in different formulations.
