Mooney viscosity of NR was examined by using Alpha Technology Rheometer MV2000.
Testing was performed by using a large rotor at 100℃ and the specimen was warmed for 1 min and tested for 4 min, as called ML(1 + 4).
Scanning electron micrographs were recorded by using JEOL® JSM5800LV and Quanta® 400 FEI.
All specimens were immersed in liquid nitrogen for 4 h and immediately fractured prior to coating with gold.