Electric birefringence of aqueous solutions of a rigid polyelectrolyte. Polarization mechanisms and anomalous birefringence signals.

HERNÁN RITACCO; DOMINIQUE LANGEVIN; CLAUDIA DOMINGUEZ; MARCOS FERNÁNDEZ-LEYES

MACROMOLECULES

AMER CHEMICAL SOC

Lugar: Washington; Año: 2016 vol. 49 p. 5618 - 5629

0024-9297

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The stationary electricbirefringence as well as built-up and decay processes give information on thepolarization mechanisms of the polyelectrolyte and on the role played by counterions.By adding a cationic surfactant (DTAB), that replaces the small Na+ counterionsof the polymer, we could obtain further insights on the role of condensedcounterions in these mechanisms. In some cases, anomalousbirefringence signals appear, revealing a new polarization mechanismlikely due to field induced interactions within polymer-surfactant aggregates.