Ionomeric blends. II. Compatibility and dynamic mechanical properties of sulfonated cis-1,4-polyisoprenes and styrene/4- vinylpyridine copolymer blends

Dynamic mechanical and optical transparency methods were used to investigate the compatibility of a series of blends of sulfonated cis-1,4-polyisoprene and styrene/4-vinylpyridine copolymers. It was found that compatibilization occurs at a degree of substitution less than 5%. It is suggested that proton transfer from the sulfonic acid group to vinyl pyridine, which results in the generation of specific anion-cation interactions, is responsible for the compatibilization, since the removal of ionic interactions through esterification destroys the compatibility.