Dimeric surfactants also known as gemini surfactants have received lots of attention for high performance formulations in the various scientific and commercial products. Due to the greater amount of hydrocarbon per molecule, the critical micelle concentrations (CMC) of dimeric are typically one order of magnitude lower than the corresponding monomeric surfactant. They are ten to hundred times more efficient at reducing the surface tension of water and the interfacial tension of the oil-water interface than conventional surfactants. Besides, the Krafft temperatures of gemini surfactants with hydrophilic spacers are generally very low giving these surfactants the capacity to be used in cold water. These surfactants display a range of interesting properties, including elevated surface activity, extremely low CMC and extraordinary rheology and selfassimilation aspect. As a consequence of these properties, they have many potential applications include detergents and cleaning agents, cosmetics, textile, and dyeing, dispersion stabilization and emulsion polymerization, genetics science, pharmaceutical, and biological applications.

Alkyl polyglucosides are non-ionic surfactants consisting of a hydrophilic saccharide moiety and a hydrophobic fatty alkyl chain. They are synthesized from renewable raw materials and have excellent ecotoxicological profiles and are readily biodegradable. The alkyl polyglucosides are mixtures of homologues, anomers and isomers. The alkyl polyglucosides with a longer alkyl chain biodegrade faster than those with a shorter one. The short to medium alkyl chain containing alkyl polyglucosides are water soluble. They exhibit favorable wetting and surface tension reduction, electrolyte and hard water tolerance, great stability in wide pH range, synergism with other surfactants and act as hydrotropes and dispersants. The dermatological, toxicological, mildness and high compatibility to skin make alkyl polyglucosides superior to all other existing surfactants. They show good functionality in various applications like detergents, food emulsifiers, cosmetic surfactants, industrial emulsifiers and pharmaceutical granulating agents.

Imidazoline derivatives, a class of novel cationic surfactants are presently gaining importance in global detergent market due to their wide range of applications. These are extensively used mainly as fabric softeners and antistatic agents. The present communication reviews the preparation, reaction scheme, reaction rates and properties of imidazoline derivatives. The analysis of imidazoline derivatives, its mode of action, their biodegradation and various applications have also been discussed.

Anionic dimeric surfactants have attracted much interest compared to the conventional monomeric surfactants. These surfactants have low critical micellar concentrations and an excellent ability in reducing the surface tension of water than conventional surfactants. Therewith, they also show better solubilizing and foaming properties, and a magnificent mildness to the skin. These special features may make them potentially attractive in several applications, for example, laundry detergents, cosmetics and personal care. This article describes the micellization and mixed micellization properties, performance properties, application and biodegradability of anionic dimeric surfactants.

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