Unformatted text preview: including a initial curing stage for 7-20 minutes at 177 o C and a post curing stage for 20-24 h at 242 o C. Figure 2.2 compares the Haake mixing torque of the different FC2260 nanocomposites during the initial curing stage. The mixing torque decreased rapidly and gradually leveled off as the elastomer was melted and mixed with the nanofillers toward higher homogeneity. The crosslinking agent was added after three minutes of mixing, and the mixing torque increased significantly, indicating the occurrence of the elastomer crosslinking. Figure 2.2 (a) shows that, before adding the crosslinking agent, the higher the treated silica (T-SiO 2 ) content, the larger the mixing torque. This was due to the viscosity increase of the elastomer caused by the added nanofiller. Before the curing agent was added, the difference in mixing torque between samples containing 0, 2, and...
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- Spring '08
- Scanning electron microscope, Fluoroelastomer Nanocomposites, initial curing stage