Study on the concentration effects in GPC: 6. A new method for determination of the radius of gyration for macromolecules

A method for determining the radius of gyration of macromolecules by the combination of GPC and viscosity measurements is presented. The molecular weight and molecular weight distribution of polymers were measured by GPC and the intrinsic viscosity was determined by capillary viscometry; then the radius of gyration for two sets of polystyrene samples (one set with the range of molecular weight, Mw = 7·4 × 104−198 × 104 and molecular weight distribution, Mw/Mn = 1·3−4·5 and the other with Mw = 12·3 × 106−40·2 × 106 and Mw/Mn = 1·2−2·0) were calculated from the relation of effective peak hydrodynamic volumes to the radius of gyration, which was derived from the theory of concentration effects of polydispersed polymers. The results show that the values of the radius of gyration are in excellent agreement with those obtained from the light-scattering method.