Studies on the Micellization Behavior of Quaternary Ammonium Cationic Surface Active Monomer AMC_(16)AB

The micellization behavior of quaternary ammonium cationic surface active-mononmer 2-acrylamidoethyl-hexadecyldimethyammonium bromide(AMC16AB) was researched. The solubility of AMC16AB was determined by UV spectrophtometry,and the critical micelle concenttation(CMC) and surface tension at CMC value(γCMC)was measured with methods of surface tension and conductibity measurements at the same time. Aggregation numbers of micelle(Nagg) of AMC16AB was determined by steady state fluorescene probe method in which prene was used as fluorescene probe and benzophenone as quencher. Meanwhile the effects of AMC16AB concentration and additional salt concenttation on aggregation numbers were also inbestigated. The experiment results show that the solubility of AMC16AB was large in pure water,while its ability of reducting water surface tension is weak, which means it has poor surface activity. Compared with the structural similar common surfactants, AMC16AB has low CMC value and krafft points,and aggregation numbers of AMC16AB micelle increases with the increasing of AMC16AB concentration. In the presence of additional salt(NaSal),at constant temperature, Nagg first increases slowly with NaSal concentration, until the critical concentration C*Sal above which Nagg increases sharply. The principle of the factors affecting the micellization behavior is similar to the common surfactants.