Determination of some hydrodynamic and thermodynamic parameters of Poly (acrylic acid) in aqueous solution of hydrochloric acid [0.001M]

The analysis of the thermodynamic behavior of polymer solutions lets us to determine several characteristics of polymers such as evaluation of the quality of solvent for aparticular polymer. Polyelectrolytes are polymers carrying either positively or negatively charged ionizable groups [1].The properties of these polymers in solutions and at chargedsurfaces depend on the fraction of dissociated ionic groups, solvent quality for polymer backbone, solution dielectricconstant, salt concentration, and polymer–solvent interactions. In general polyelectrolytes exhibit solution properties quitedifferent from those of non-ionic polymers [1]. Because polyelectrolytes dissociate counter ions, their solutions have at least three components: polymer, counter ion and solvent [2].With unfavorable polymer–solvent interactions, polymer coils can completely collapse and become insoluble in the fluid [3].In this work we measure the intrinsic viscosity, expansion factor, the entropy of dilution parameter, the heat of dilutionparameter and Flory–Huggins thermodynamic interaction parameter via viscometric data for poly acrylic acid in aqueous solution of hydrochloric acid with 0.001 M in severaltemperatures. In salted aqueous solutions or acidic solutions if sufficient salt or inorganic acid is present polyelectrolyteswork in exactly the same manner as for neutral polymers. A high concentration of counter ions is provided by addition of acid, and then the electrostatic effects are suppressed.