pNa測定による界面活性剤-高分子混合溶液の研究

抄録

The concentration of the free counterion of an ionic surfactant has been measured for the mixed polymer-surfactant solutions, and the degree of ionic dissociation (α) of the surfactant has been calculated from the pNa data of these mixed solutions. The polymers examined were polyvinylpyrrolidone (PVP), polyethylene glycol (PEG) and polyvinylalcohol (PVA), and the surfactant was sodium dodecyl sulfate (NaDS). The value of α increases with increase in mixing ratio of polymer/NaDS (monomer unit mol/mol) and tends to decrease with increase in the molecular weight of polymer. The absolute value of α increases in the order PVP>PEG>PVA, namely in the order of increasing hydrophobic character of the polymer. From these results, authors discussed the mode of binding of NaDS onto these polymers. It was suggested that the surfactant is bound onto PVP or PEG forming aggregates on it in such a manner as micelle formation, but onto PVA the surfactant is bound monomolecularly.