Dilute solution properties of poly(3-trimethyl methacrylamido propyl ammonium methylsulfate)

Abstract

The properties of a novel cationic, poly(trimethyl methacrylamido propyl ammonium methylsulfate), poly(TMMPAMS) in aqueous solution are examined in this study by measuring intrinsic viscosity, degree of binding, ionic strength, and flocculation. This cationic polyelectrolyte's intrinsic viscosity and degree of binding are dependent on the type and concentration of salt added to the aqueous solution. The intrinsic viscosity behavior of the cationic polyelectrolyte resulting from the electrostatic repulsive force of the polymer chain is contrasted with polyampholyte. In the presence of KCl, the polyelectrolyte has a lower degree of binding, indicating that the proton ion (H +) has difficulty binding to CH 3SO 4 − in poly(TMMPAMS) solution. An increase in ionic strength caused the pKa to decrease at the half-neutralization point. Optimum flocculation of bentonite suspensions, corresponding to the complete removal of turbidity from the supernatant, is achieved. Beyond the optimum flocculation, high polymer dosages redisperse the bentonite suspensions. The pH range of the optimum flocculation is found to be 4–9. Models are proposed to account for the poly(TMMPAMS) solution viscometrics and the degree of binding.