Thermodynamic and Conformational Properties of Polystyrene. I. Light-Scattering Studies on Dilute Solutions of Linear Polystyrenes

Abstract

The results of an extensive study of some dilute solution properties of a series of linear, homogeneous (anionically prepared) polystyrenes (4.8<10−4M<440) over a wide temperature interval (10°<T<110°C) in decalin and toluene are described. The data are used to obtain detailed comparisons among the second virial coefficient A2, the mean-square molecular radius 〈s2〉, the molecular weight M, and the temperature. The empirical correlations thus obtained are compared to theoretical predictions. In particular, it is found that A2M½(〈s2〉/M)0−32 and α2=〈s2〉/〈s2〉0 are each single-valued functions of the interaction parameter z=B(〈s2〉0/M)0−32M½, when B is assumed to have the temperature dependence B=B0[1—(Θ/T)]. Certain theoretical predictions for the dependence of A2M½/α3 on z/α3 are found to adequately describe the form of the observed behavior and can be used as the basis for a satisfactory empirical relation. The observed dependence of α2 on z is satisfactorily predicted by recent calculations of Flory and Fisk. It is expected that the correlations given among A2, α2, and z will be valid for any flexible, nonionic polymer.