Solubilization of methacrylic acid based polymers by surfactants in acidic solutions.
The effect of various surfactants on the solubility of methacrylic acid based polyelectrolytes that are insoluble in water at low pH, i.e. isotactic poly(methacrylic acid), i-PMA, Luviflex Soft and Luviflex Silk, was studied by surface tension, fluorescence spectroscopy, potentiometric titration and dynamic light scattering, DLS, measurements. Results show that Luviflex Silk and Luviflex Soft form polymeric micelles in aqueous solutions above a well-defined concentration, whereas both i-PMA and Luviflex Soft undergo a pH-induced conformational transition. The critical association concentration values for each surfactant in the presence of completely ionized polyions were determined. Potentiometric and DLS measurements show that the addition of an anionic and a nonionic surfactant significantly increases the solubility of the polymers at low pH, while the presence of a cationic surfactant results in a formation of an insoluble polymer-surfactant aggregate. The present results could help in regulating the removal of hair-setting polymers by water.
Vlachy
Nina
N
Department of Chemistry and Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Askerceva 5, PO Box 537, SI-1000 Ljubljana, Slovenia.
Touraud
Didier
D
Kogej
Ksenija
K
Kunz
Werner
W