Nanoscale visualization and multiscale mechanical implications of bound rubber interphases in rubber–carbon black nanocomposites

The concept of a “bound rubber” phase extending over nanometre-scale distances from the interface of rubber-particle nanocomposites is generally accepted. However, the thickness and elastic properties of this interphase have not been confirmed by direct experimental observation. Here, we demonstrate the existence of bound rubber in hydrogenated nitrile butadiene rubber (HNBR)–carbon black composites, through direct visualization and measurement...