INCOMPATIBILITY OF POLYMER-SOLUTIONS .3. CRITICAL OPALESCENCE IN SYSTEM POLYSTYRENE + POLYISOBUTYLENE + TOLUENE

In the reported experiments, the angular dependence of light scattering from the homogeneous ternary system PS plus polyisobutylene plus toluene was measured at a fixed (critical) concentration as a function of temperature. On approaching the critical temperature the scattering becomes very large and strongly angle-dependent. The experiments show that the interaction range r//G is of the same order of magnitude as the molecular radius of gyration of the polymer, but cannot be set equal to it as in the case of a binary system of one polymer in a single solvent. The temperature dependence of the various interaction parameters does not depend on the mol. wt of the polymers.