| Abstract
| - We have examined the polymer/surfactant interaction in mixed aqueous solutions of cationic surfactantsand anionic polyelectrolytes combining various techniques: tensiometry, potentiometry with surfactant-selective electrodes, and viscosimetry. We have investigated the role of varying polymer charge density,polymer concentration, surfactant chain length, polymer backbone rigidity, and molecular weight on thecritical aggregation concentration (Cac) of mixed polymer/surfactant systems. The Cac of these systems,estimated from tensiometry and potentiometry, is found to be in close agreement. Different Cac variationswith polymer charge density and surfactant chain length were observed with polymers having persistencelengths either smaller or larger than surfactant micelle size, which might reflect a different type of molecularorganization in the polymer/surfactant complexes. The surfactant concentration at which the viscositystarts to decrease sharply is different from the Cac and probably reflects the polymer chain shrinkage dueto surfactant binding.
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