Zwitterion betaine surfactant

Most studies of micellar systems have been carried out on synthetic surfactants where the polar or ionic head group may be cationic, e.g. an ammonium or pyridinium ion, anionic, e.g. a carboxylate, sulfate or sulfonate ion, non-ionic, e.g. hydroxy-compound, or zwitterionic, e.g. an amine oxide or a carboxylate or sulfonate betaine. Surfactants are often given trivial or trade names, and abbreviations based on either trivial or systematic names are freely used (Fendler and Fendler, 1975). Many commercial surfactants are mixtures so that purity can be a major problem. In addition, some surfactants, e.g. monoalkyl sulfates, decompose slowly in aqueous solution. Some examples of surfactants are given in Table 1, together with values of the critical micelle concentration, cmc. This is the surfactant concentration at the onset of micellization (Mukerjee and Mysels, 1970) and can therefore be taken to be the maximum concentration of monomeric surfactant in a solution (Menger and Portnoy, 1967). Its value is related to the change of free energy on micellization (Fendler and Fendler, 1975 Lindman and Wennerstrom, 1980). 

Extra mild surfactants (nonionic) polyethoxylated sorbitan ester Combination with amphoteric or zwitterionic surfactants cocamidopropyl betaine Surfactants/glycol soap agents Cationic surfactants Cationic polymers Silicones and derivatives... 

In the present work, we have synthesized two betaines and three sulfobetaines in very pure form and have determined their surface and thermodynamic properties of micellization and adsorption. From these data on the two classes of zwitterionics, energetics of micellization and adsorption of the hydrophilic head groups have been estimated and compared to those of nonionic surfactants. 

In Figure 1, the log of the cmc is shown as a function of the number of carbon atoms in the hydrocarbon chain, n, . It is clear that the nonionic surfactants (hexaethyleneglycol alkyl ethers) and the zwitterionic surfactants (N-alkyl betaines) exhibit linear relations with similar slopes of about -0.5... 

Betaine, or trimethyl glycine, is a naturally occurring zwitterionic nutrient that was first discovered in beets but occurs in a wide variety of plants and animals. Surfactant betaines are structurally analogous compounds but they are manufactured synthetically. 

Snow, S.A., Fenton, W.N. and Owen, M.J. (1991) Zwitterionic organofunctional siloxanes as aqueous surfactants - synthesis and characterization of betaine functional siloxanes and their comparison to sulfobetaine functional siloxanes. Langmuir, 7(5), 868-71. 

Surfactants Ionic, anionic (e.g., sodium dodecyl sulphate, Cj2H250S03 Na ), cationic (e.g., cetyl trimethyl ammonium chloride, Ci,H33-N+(CH3)3C1-), zwitterionic [e.g., 3-dimethyldodecylamine propane sulphonate (betaine CJ2H25-N" (CH3)2-CH2-CH2-CH2-S03)], nonionic, alcohol ethoxylates C H2 +i-0-(CH2-CH2-0) -H, alkyl phenol ethoxylates C H2 +i-CgH4-0-(CH2-CH2-0) -H, amine oxides (e.g., decyl dimethyl amine oxide, C10H21-N ( 113)2 0), and amine ethoxylates. 

For zwitterionics of the betaine and sulfobetaine types, Ci2H25N+(CH3)2(CH2)m COO- and C12H25N+(CH3)2(CH2)3S03-, respectively, the micellar aggregation number varies very little with change in surfactant concentration or electrolyte content (Kamenka, 1995a). 

Submicroscopic, colloidal aggregates can influence chemical reactivity. Aqueous micelles are the most widely studied of these aggregates, and these micelles form spontaneously when the concentration of a surfactant (sometimes known as a detergent) exceeds the critical micelle concentration, cmc (1-3). Surfactants have apolar residues and ionic or polar head groups, and in water at surfactant concentrations not much greater than the cmc, micelles are approximately spherical and the polar or ionic head groups are at the surface in contact with water. The head groups may be cationic, (e.g., trimethylammonium), anionic, (e.g., sulfate), zwitterionic (as in carboxylate or sulfonate betaines), or nonionic. The present discussion covers the behavior of ionic and zwitterionic micelles and their effects on chemical reactivity. 

Thus far, only ionic micelles have been discussed, but some results were obtained for reactions in zwitterionic micelles of the betaine (Bl-12) and the sulfobetaine (SB3-16). These surfactants differ in that the carboxylate moiety of Bl-12 could react nucleophilically, and this behavior is observed in... 

Amine oxide zwitterionics are not strongly DR effective. At low temperatures oleyl dihydroxyethyl amine oxide (OHAO) shows weak drag reduction from 5 to 15°C. At high temperatures, behenyl dihydroxyethylamine oxide (BMAO) is weakly DR from 60 to 80°C. However, when 2-lauryl carboxymethyl hydroxyethyl imidazolium betaine was added to OHAO at a ratio of 1 to 1.5, at 15°C DR was increased from 55% to 70%. The surfactant also increased drag reduction from 10% to 88% at 80°C when added to BMAO [Nobuchika et al., 2000]. 

Zwitterionic surfactants, also known as amphoteric surfactants, have both cationic and anionic centers present in the same molecule. Generally, their properties are highly dependent on the pH of the solution. The cationic part is based on primary, secondary, or tertiary amines or quaternary ammonium cations. The anionic part can be more variable and include sulfonates, as in CHAPS (3-[(3-Cholamidopropyl)dimethylammonio]-l-propanesulfonate). Other anionic groups are sultaines illustrated by cocamidopropyl hydroxysultaine. Examples of zwitterionic surfactants include betaines (such as cocamidopropyl betaine, dodecyl betaine, lauramidopropyl betaine and cocoamido-2-hydroxypropyl sulfobetaine) and phosphates (such as lecithin). 

Uses Surfactant, hydrotrope, cleansing agent, foaming agent, vise, builder in cosmetics Trade Name Synonyms Incromine Oxide Mink t[Croda Inc http //www.croda.com] Minkamidopropyl betaine Synonyms N-(Carboxymethyl)-N,N-dimethyl-3-[(1-oxomink) amino]-1-propanaminium hydroxide, inner salt Minkamide propylbetaine Minkamidopropyl dimethyl glycine 1-Propanaminium, N,N-dimethyl-N-carboxymethyl-3-amino-, N-mink oil acyl derive., hydroxides, inner salts Classification Zwitterion (inner salt)... 

Formula CH3(CH2)i2CONH(CH2)3N(CH3)2 O Uses Antistat, surfactant in cosmetics Myristamidopropyl betaine CAS 59272-84-3 EINECS/ELINCS 261-684-6 Synonyms N-(Carboxymethyl)-N,N-dimethyl-3-[(1 -oxotetradecy I) am i no]-1 -propanami n i um hydroxide, inner salt (Carboxymethyl) di methyl-3-[( 1 -oxotetradecyl) am i no] propylammonium hydroxide Myristamidopropyl dimethyl glycine Classification Zwitterion (inner salt)... 

Synonyms Amides, palm oil, N-(2-hydroxypropyl)- N-(2-Hydroxypropyl) palm oil acid amide Monoisopropanolamine palm oil acid amide Palm oil acid amide, N-(2-hydroxypropyl)- Palm oil acid monoisopropanolamide Definition Mixt. of isopropanolamides of the fatty acids derived from palm oil Formula RCONHCH2CH3CHOH where RCO- rep. fatty acids derived from palm oil Uses Emulsifier, emulsion stabilizer, surfactant, vise, control agent in cosmetics Palmamidopropyl betaine Synonyms 1-Propanaminium, N-carboxymethyl-N,N-dimethyl-3-amino-, N-(palm-oil acyl) derive., hydroxides, inner salts Classification Zwitterion (inner salt)... 

PEG-30 hydrogenated tallowamine PEG-200 trihydroxystearin Steareth-30 surfactant, wool wash compounds TEA-dodecylbenzenesulfonate surfactant, zinc galvanization Butoxynol-19 carboxylic acid surfactant, zwitterionic buffers N,N-Dimethyl-N-lauric acid-amidopropyl-N-(3-sulfopropyl)-ammonium betaine N,N-Dimethyl-N-myristyl-N-(3-sulfopropyl)-... 

The betaines, especially the coconut-oil-derived cocamidopropyl betaines, are the most important zwitterionic surfactants. The name betaine refers to trimethylglycine, which was first isolated from sugar beet beta vulgaris). Cocoamphomonoacetate and cocoamphodiacetate are the most important types for the amphoteric surfactants. The structures and names for both product types are summarized in Table 15.1. 

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