DETERGENT

DETERGENT
A detergent is a surfactant or a mixture of surfactants with "cleaning properties in dilute solutions." These substances are usually alkylbenzenesulfonates, a family of compounds that are similar to soap but are more soluble in hard water, because the polar sulfonate (of detergents) is less likely than the polar carboxyl (of soap) to bind to calcium and other ions found in hard water.In most household contexts, the term detergent by itself refers specifically to laundry detergent or dish detergent, as opposed to hand soap or other types of cleaning agents.
Detergents are commonly available as powders or concentrated solutions. Detergents, like soaps, work because they are amphiphilic: partly hydrophilic (polar) and partly hydrophobic (non-polar). Their dual nature facilitatesthe mixture of hydrophobic compounds (like oil and grease) with water. Because air is not hydrophilic, detergents are also foaming agents to varying degrees.
Anionic detergents
Typical anionic detergents are alkylbenzenesulfonates. The alkylbenzene portion of these anions is lipophilic and the sulfonate is hydrophilic. Two different varieties have been popularized, those with branched alkyl groupsand those with linear alkyl groups. The former were largely phased out in economically advanced societies because they are poorly biodegradable. An estimated 6 billion kilograms of anionic detergents are produced annually for domestic markets.
Bile acids, such as deoxycholic acid (DOC), are anionic detergents produced by the liver to aid in digestion and absorption of fats and oils.
Cationicdetergent
Cationic detergents are similar to the anionic ones, with a hydrophobic component, but, instead of the anionic sulfonate group, the cationic surfactants have quaternary ammonium as the polar end. The ammonium center is positively charged.
Non-ionic and zwitterionic detergents
Non-ionic detergents are characterized by their uncharged, hydrophilic headgroups. Typical non-ionic detergents arebased on polyoxyethylene or a glycoside. These materials are also known as ethoxylates or PEGlyates and their metabolites, nonylphenol. Glycosides have a sugar as their uncharged hydrophilic headgroup. Examples include octyl thioglucoside and maltosides. HEGA and MEGA series detergents are similar, possessing a sugar alcohol as headgroup.
Zwitterionic detergents possess a net zero charge arisingfrom the presence of equal numbers of +1 and −1 charged chemical groups. Examples include CHAPS.
GLOSSARY
surfactant.- are compounds that lower the surface tension (or interfacial tension) between two liquids or between a liquid and a solid. Surfactants may act as detergents, wetting agents, emulsifiers, foaming agents, and dispersants.
HARD WATER.-is water that has high mineral content (in contrastwith "soft water"). Hard water is formed when water percolates through deposits of limestone and chalk which are largely made up of calcium and magnesium carbonates.
AMPHIPHILE.-is a chemical compound possessing both hydrophilic (water-loving, polar) and lipophilic (fat-loving) properties.
HYDROPHILE.-is a molecule or other molecular entity that is attracted to, and tends to be dissolved by,water.
HYDROPHOBICITY.- is the physical property of a molecule (known as a hydrophobe) that is seemingly repelled from a mass of water.
FOAMING AGENTS.- is a material that facilitates formation of foam such as a surfactant or a blowing agent. A surfactant, when present in small amounts, reduces surface tension of a liquid (reduces the work needed to create the foam) or increases its colloidalstability by inhibiting coalescence of bubbles
POLYETHYLENE GLYCOL (PEG) is a polyether compound with many applications from industrial manufacturing to medicine.
GLYCOSIDE.-is a molecule in which a sugar is bound to another functional group via a glycosidic bond
ZWITTERION.-is a neutral molecule with a positive and a negative electrical charge, though multiple positive and negative charges can be...