What kind of interaction is possible between SDS and Ag+?
Sorry, I don't understand the question: you mean some *additional* interaction on top of the usual electrostatics??
The SDS in water has a negatively charged head (the sulfate residue) which of course very strongly attached to a positive metal ion (replace Na+ with Ar+).
SDS in water will disassociate in to DS- (RSO4-) and Na+, if there is Ag+ ions how they interact?. Will they interact by electrostatically? or Weak acid-weak base interaction?
The Ag ions will compete with the Na ions a counter ions for the Na/AgDS micelles and monomers. As Ag2SO4 is poorly soluble in water, the interaction between Ag+ and SO42- is fairly strong and not only electrostatic but also specific. The attrition between Na and SO4 is mainly electrostatic. As the attraction between Ag and SO4 is stronger than Na SO4 the surfactant will be mainly in the AG form and even become insoluble.
If I remember correctly, the solubility of AgDS is lower than its cmc at room temperature. There is a strong van der Waals interaction between Ag(+) and DS(-), since Ag(+) is notorious for its high polarizability. For this reason, AgDS will adsorb more, it has lower cmc (at high temperatures, where it has a cmc at all), etc. I don't expect hydrolysis at normal pH.
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