The effect of temperature on thermodynamic parameters of micellization of some surfactants

Abstract

The micellization of anionics surfactants (SDS, sodium dodecyl sulphate and SU, surfactin) and cationic surfactants (BC, benzalkonium chloride, TTAB, tetradecyltrimethylammonium bromide and HTAB, hexadecyltrimethylammonium bromide) were investigated at various temperatures using a du Nouy ring tensiometer. The cmc decreased to a certain minimum and then increased with the temperature, displaying a U-shaped behavior. This behavior was analyzed using a power-law equation. The thermodynamic parameters of micellization, ΔGm, ΔHm and ΔSm were obtained at different temperatures. © 2007 Asian Network for Scientific Information.