Effect of dissolved polystyrene upon relaxation times of protons in mixed solvents

Abstract

T ₁ measurements were made for each species of proton as a function of solution composition for the solvent, non-solvent pairs benzene + cyclohexane, benzene + heptane, and dioxane + heptane. When polystyrene is dissolved in these mixtures, the relaxation times of the solvent protons are reduced. Calculations of preferential adsorption of good solvent by polymer can be fitted to the data obtained from light-scattering results for the systems benzene + cyclohexane + polystyrene, and for benzene + heptane + polystyrene but not for dioxane + heptane + polystyrene.