Abstract: The surface tension and surface absorption of a new surfactant,the 3-alkoxy-2-hydroxypropyl trimethylammonium bromide,have been investigated by drop-volume method at different temperature. Some thermodynamic parameters were calculated according to corresponding formula. It was found that the surface tension and critical micelle concentration of C_nNBr decrease with the inerease of the length of hydrocarbon chain and the temperature. The change of thermodynamics functions indicates that the micellization pr...