Investigating pyrolytic carbon black in natural rubber compounds: rheological, mechanical and dynamic effects

The automotive industry, the highest consumer of carbon black, has established specific targets to integrate effective alternative materials such as pyrolytic carbon black. The purpose of this study is to explore the role of pyrolytic carbon black as a potential alternative filler in the rubber industry, focusing on its effects on processing, rheological, mechanical and dynamic properties. Four compounds were prepared using two pyrolytic carbon blacks with different surface areas and two conventional carbon blacks that are N330 and N550. The results indicated that the use of pyrolytic carbon black increases scorch and optimum cure times and decreases maximum and minimum torque. Tensile strength, elongation at break, modulus at 100% elongation and hardness of the compounds before and after aging were obtained and discussed. In addition, dynamic properties were obtained and it was observed that pyrolytic carbon black decreases tan delta. Pyrolytic carbon black also significantly decreases compound viscosity, enhancing processability. The thermal conductivity of compounds containing pyrolytic carbon blacks and conventional carbon blacks were also analyzed. Based on these findings, pyrolytic carbon black can be used as an alternative filler for specific applications.