Studies on micelle ionization for sodium dodecyl sulfate in aqueous solution using weak electrolytes theory

Above the critical micelle concentration, sodium dodecyl sulfate (SDS) can aggregate and form micelle in aqueous solution. It will display its own con ductance behavior different from that of general strong electrolyte solutio n. Therefore, we proposed a new model, named as micelle ionization model, w here the micelle is treated as one kind of weak electrolyte and the molar c onductivity is expressed by conductance equation of weak electrolyte, The f ormula for calculating the micelle ionization degree for SDS is deduced. Ac cording to the observed conductance data of SDS aqueous solutions in this w ork, the ionization degree of SDS micelle is determined, The calculated val ues of the ionization degree are in good agreement with those from literatu res, which indicates that the new model can be used satisfactorily to descr ibe the conductance behavior of ion-type surfactant SDS solution.