Structural and Thermal Properties of Nitrile-Butadiene Rubber Reinforced with ISAF Carbon Black

In this study, nitrile–butadiene rubber (NBR) composites reinforced with intermediate super abrasion furnace (ISAF) carbon black at different loadings (50, 60, 70, 80, 90, and 100 phr) were systematically investigated. Structural analysis via X-ray diffraction (XRD) revealed that the composites exhibited a predominantly amorphous character with a filler-dependent degree of crystallinity. Fourier transform infrared (FTIR) spectroscopy was employed to identify the functional groups involved in ionic crosslinking within the NBR matrix. Thermal stability was evaluated through thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) over the temperature range from ambient conditions to 400 °C, which revealed a significant increase in stability with increasing carbon black concentration. These results provide comprehensive insight into the intricate correlation between filler loading and the resulting thermal behavior of elastomeric composites. The findings reveal that variations in carbon black content significantly influence the heat transfer characteristics, thermal stability, and degradation resistance of the rubber matrix. Higher-structure grades tend to enhance thermal conductivity and improve heat dissipation, while optimal filler loading promotes balanced mechanical integrity and thermal performance. Overall, this understanding contributes to the rational design and optimization of carbon black–reinforced elastomeric materials tailored for advanced engineering applications requiring superior durability and thermal management capabilities.