COLLAPSE OF POLY(METHACRYLOYLETHYL TRIMETHYLAMMONIUM METHYLSULFATE) ON ADDITION OF ACETONE INTO AN AQUEOUS-SOLUTION

The effect of the solvent composition on the conformation of a super h igh molar mass polyelectrolyte, M-w = 22-25 X 10(6), dissolved in a wa ter-acetone mixture was investigated using static and dynamic light sc attering. When increasing the concentration of acetone above 80 mass p ercent, a reversible conformational change of macromolecules occurs, w hich causes a sharp decrease in the viscosity, a rise in the light sca ttering intensity, and also a decrease in the radius of gyration, R-g, the hydrodynamic radius, Rh, as well as in the second virial coeffici ent A(2). The correlation function measured by dynamic light scatterin g changes from bimodal to unimodal indicating the formation of compact globular structures. (C) 1998 Elsevier Science Ltd. All rights reserv ed.