Amphoteric surfactants geminis

U.S. 5968496 (1999) U.S. 5922671 (1999) Linares et al. (Procter Gamble) Tracy et al. (Rhodia) (a) Imidazolinium amphoteric surfactant (b) polyol alkoxy ester (a)/(b) = 15 1-1 1 Bis-alkyphenol alkoxylated Gemini surfactants Excellent cleaning performance and mildness improved foam stability Improved surfactant properties mild and environmentally benign... 

Our group designed and synthesized a new elass of amino acid-based gemini surfactants of the bis(Quats) type (quaternary ammonium salt) (Scheme 2). These consist of 2 hydrophobic chains of 12 carbon atoms, 2 quaternary ammonium groups, and 1 spacer chain containing amide and disulfide bonds [63,64], They derived from the condensation of 7V-dodecyl-A, A -dimethylgly-cine (a well-known soft amphoteric surfactant) with amino acid derivatives containing disulfide bonds, i.e., cystine 1 and cystamine 2 (Scheme 2). 

These are nonionic organic surfactants, cationic surfactants, amphoteric surfactants, perfluormated surfactants, and gemini surfactants (21). A wide variety of examples have been given. Some are listed in Table 4.11 and shown in Figure 4.6. 

The gemini-containing cationic [quaternary ammonium salts, called bis (Quats)], anionic (phosphate, sulfate, carboxylate), amphoteric and nonionic (polyether or sugar), polar groups have been a matter of numerous investigations [59]. Only few studies have been done on the physicochemical and biological properties of amino acid-based gemini surfactants [60-62]. 

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