Deuteration Impact on Micellization Pressure and Cloud Pressure of Polystyrene-<i>block</i>-polybutadiene and Polystyrene-<i>block</i>-polyisoprene in Compressible Propane

Abstract

The deuterated homopolymers and their corresponding polystyrene-<i>block</i>-polybutadiene and polystyrene-<i>block</i>-polyisoprene copolymers require lower cloud pressures than their hydrogenous analogues to dissolve in a compressible alkane solvent, such as propane. For symmetric diblocks, deuteration reduces the micellization pressure. By contrast, for asymmetric diblocks with a long diene block relative to the styrene block, deuteration can increase the micellization pressure. All in all, however, the deuteration effects, while measurable, do not qualitatively change the principal diblock properties in compressible propane solutions, such as pressure-induced micelle decomposition, micelle formation and micelle size, and their temperature dependence. Therefore, isotope labeling should be a useful approach to neutron-scattering characterization for styrene-diene block copolymers in compressible alkane systems.