Sulfur vulcanization in the processing and compounding of rubber by Hancock and his colleagues led to a more reliable process. Around 1900, disulfiram was introduced as a vulcanizing agent, and became widely used. In 1905 George Oenslager discovered that a derivative of aniline called thiocarbanilide accelerated the reaction of sulfur with rubber, leading to shorter cure times and reducing energy consumption. This breakthrough was almost as fundamental to the rubber industry as Goodyear's sulfur cure. Accelerators made the cure process faster, improved the reliability of the process and enabled vulcanization to be applied to synthetic polymers. One year after his discovery, Oenslager
Rubber toughening systems. Rubber particles toughen a system by a variety of mechanisms such as when particulates concentrate stress causing cavitation or initiation of dissipating crazes. However the effects are not one-sided; excess rubber content or debonding between the rubber and polymer can reduce toughness. It is not possible to state the specific effects of a given particle size and interfacial adhesion parameter due to numerous other confounding variables. The presence of a given failure mechanism is determined by many factors: those intrinsic to the continuous polymer phase, and those that are extrinsic, pertaining to the stress, loading speed, and ambient conditions.