Sulfur vulcanization had found hundreds of applications for his additive. Thus, the science of accelerators and retarders was born. An accelerator speeds up the cure reaction, while a retarder delays it. A typical retarder is cyclohexylthiophthalimide. In the subsequent century chemists developed other accelerators and ultra-accelerators, which are used in the manufacture of most modern rubber goods. Sulfur vulcanization Sulfur vulcanization or sulfur vulcanisation is a chemical process for converting natural rubber or related polymers into more durable materials by heating them with sulfur or other equivalent curatives or accelerators. Sulfur forms cross-links (bridges) between sections of polymer chain which results in
Rubber toughening measure the separate contributions. Shear yielding is a constant volume process and cannot be measured with tensile dilatometry. Voiding can be seen with optical microscopy, however one of two methods, using polarized light or low angle light scattering are necessary to observe the connection between cavitation and shear bands. In order to gauge the toughening effects of a dispersed secondary phase, it is important to understand the relevant characteristics of the continuous polymer phase. The mechanical failure characteristics of the pure polymeric continuous phase will strongly influence how rubber toughened polymer failure occurs. When a polymer usually fails due to