Rheological study on mixtures of different molecular weight hyaluronates.

The shear flow of hyaluronate solutions prepared from mixtures of hyaluronates with different molecular weights has been studied. This paper shows that prediction of the rheological behaviour of polymer mixtures at a given polymer concentration is possible knowing the intrinsic viscosity of the different mixed samples and the general variation of the specific viscosity versus the overlap parameter C[eta]. These characteristics depend on the total ionic strength in solution and have been determined for three conditions: in 0.1 M NaCl and at ionic strengths corresponding to hyaluronate concentrations of 5 and 10 g l-1 in pure water. The differences between the predicted viscosities and the measured ones are usually lower than 5% for the three conditions tested.