INVESTIGATIONS ON THE DISSOCIATION BEHAVIOR OF HYDROLYZED ALTERNATINGCOPOLYMERS OF MALEIC-ANHYDRIDE AND PROPENE .2. VISCOMETRIC BEHAVIOR

The viscometric behaviour of hydrolyzed propene maleic anhydride copol ymers of different molecular weights has been investigated in aqueous solution as a function of polymer concentration, degree of neutralizat ion, concentration of added salt (NaCl) and temperature, respectively. In salt free solutions the reduced viscosity increases with decreasin g polymer concentration. Addition of salt to the solutions restores co nformity with the Huggins' equation. At constant degree of neutralizat ion the intrinsic viscosity was found to have an inverse square-root d ependence on salt concentration. The dependence of the viscosity on th e degree of neutralization indicates a maximum at half the degree of n eutralization. This maximum disappears with decreasing molecular weigh t. The behaviour of the copolymer at pressure filtration through a pol ypropene membrane filter was compared with the results of viscometry. Copyright (C) 1996 Elsevier Science Ltd.