Alkanediyl-α,ω-Bis(dimethylalkylammonium Bromide) Surfactants

Thermodynamics of micellization for partially fluorinated cationic gemini surfactants and related single–chain surfactants in aqueous solution

“…These trends are similar to those found for the hydrocarbon gemini surfactant 12-2-12 and the corresponding monomeric surfactant DTAB [28,29]. The large differences in CMC and H mic between gemini surfactants and the corresponding monomeric surfactants arise mostly from the transfer of the surfactant hydropho- bic chains from the aqueous phase to the micelle core.…”

“…The long spacer therefore enhances the hydrophobicity of the surfactant and the micelle can form at a correspondingly lower concentration. Grosmaire et al [29] have reported the opposite result for H mic of hydrocarbon gemini surfactants. They found that H mic becomes more exothermic as the spacer length changes from 6 to 12 and explained the result in terms of the change in the spacer microenvironment.…”

Alkanediyl-α,ω-bis(dimethylalkylammonium bromide) Surfactants: II. Krafft Temperature and Melting Temperature

“…The properties of these surfactants have been reviewed (6,7). The alkanediyl-α,ω-bis(alkyldimethylammonium bromide) surfactants have been the most thoroughly investigated dimeric surfactants (1)(2)(3)(8)(9)(10)(11)(12)(13)(14). They are often referred to as m-s-m, where m and s are the numbers of carbon atoms of the alkyl and alkanediyl groups, respectively.…”

“…However, the effect of the spacer carbon number s on the above properties was often unexpected. On the one hand, the cmc is a maximum (3), whereas the absolute value of the enthalpy of micellization (8) and the volume of micellization (9) are a minimum at s = 5 to 6. On the other hand, at s = 10 to 12, the surface area occupied by one surfactant at the air/solution interface is a maximum (10,11).…”

Síntese e propriedades de soluções de tensoativos catiônicos derivados de (3-dimetilaminopropil)amidas de ácidos carboxílicos

“…(4) GU et al, 1996 Os fatores que contribuem para a entalpia de micelização são os seguintes (GROSMAIRE et al, 2002): Todas as contribuições parciais para a entropia total se mostram favoráveis a micelização.…”