Multifunctional Gemini Surfactants: Structure, Synthesis, Properties and Applications

Abstract

Gemini cationic surfactants are compounds which are composed of two hydrophilic head groups and two hydrophobic tails linked by a spacer at the head groups or closed to them. The spacer can be either hydrophobic or hydrophilic. It can be rigid or flexible. The neutral charge of the molecule is retained by the presence of organic or inorganic counterions. Critical micelle concentrations (CMCs), surface tension (γ) and minimal inhibitory concentration (MIC) are dozen times lower than corresponding parameters of monomeric surfactants. The unique properties of gemini surfactants with a wide range of hydrophiliclipophilic balance (HLB) make them a very useful, innovative material in detergents, cosmetics, personal care products, additives for paints and coatings, biocides, material science, organic synthesis, pharmacy, textiles, enhanced oil recovery, nanotechnology, petroleum and many other branches of life. A large number of papers concerning gemini surfactants have been published so far. This review presents a synthetic look at current work devoted to structure, synthesis and applications of gemini surfactants.

Surface and thermal properties of synthesized cationic poly(ethylene oxide) gemini surfactants: the role of the spacer

“…11 Due to these properties, gemini surfactants are widely used in coatings, paints, pharmaceuticals, nanomaterials, household, cosmetics, detergents, and various oileld applications including enhanced oil recovery. 12 Among the various classes of surfactants, the amido-amine type gemini cationic surfactants continue to receive the attention of researchers because of their high performance in industrial applications. 13 With proper structural design of gemini cationic surfactants, it is possible to achieve a high degree of control on their physicochemical properties.…”

Synthesis of Sugar-Containing Surfactants Based on 8-Hydroxyoctanoic Acid

“…Слід також зазначити, що все ширше використання знаходять ПАР, які одержують модифікацією сполук природного походженняамінокислот, олій і сахаридів [3][4][5][6]. Останнім часом також інтенсивно досліджується такий клас поверхнево-активних речовин, які містять спарені ліпофільні або гідрофільні блоки, так звані "Gemini-surfactants" -сурфактанти-близнюки [7][8][9].…”

Micellization thermodynamic behavior of gemini cationic surfactants. Modeling its adsorption at air/water interface

“…In comparison with their corresponding monomeric counterparts, gemini surfactants show a higher surface activity, and lower critical micelle concentrations (CMCs) and Kraft temperatures 9,10 , as well as forming in solution many different morphological micellar structures, vesicles, helices or tubules 11,12 . All these properties make them suitable for many different industrial processes 13,14 as emulsifiers, dispersants, coating agents and corrosion inhibitors, and biophysical applications 2,15,16 such as membrane solubilization, drug delivery systems or gene delivery by DNA-compaction, amongst others.…”