Hello everyone,

I have a problem with estimating CMC values of oligomeric cationic surfactants from conductometry. My compounds are quaternary ammonium slats, dimeric, trimeric and tetrameric, derivates of benzene. For compounds with short alkyl chain (C4, C6, C8, C10), the relationship between conductivity and concentration is a straight line, no change of slope. Moreover, for tetrameric salts, a graph looks completely different, first a plateau is observed and then the conductivity increases. Has anyone had the same problem and could help me with solving that?

I would be grateful for any help.

Thank you in advance.

Kind regards.