We have studied the complexation of polyelectrolyte (sodium poly(styren sulfonates) : PSS) and cationic surfactant (Tetradecyl Trimethyl Ammonium Bromide :TTAB) by dynamic light scattering (DLS). We checked some characteristic behaviors of polyelectrolytes and ionic surfactants - effective charge interaction, conformational changes, aggregation of the complexes that they make, and so on.
In the very dilute TTAB concentration near CAC, this system is thermodynamic equilibrium and can be explained by the free energy, but cannot be explained in the same way in the high TTAB concentration over CAC.