Results and discussion
3.1. Vulcanization characteristics
As the HNBR blend rate was increased, vulcanization speed and scorch time decreased, because it created a curve with a continual increase (tc90 as a normal vulcanization time is meaningless with no consistency). Thus in this experiment, tc50 was adopted as the blended specimen vulcanization character comparative data. As a result, as HNBR blend rate was increased, the tc50 tended to be delayed, demonstrating that the tc50 was influenced by the vulcanization character of the HNBR Figs. 1 and 2, Tables 3 and 4.