Green Modification of Pyrolysis Carbon Black Based on Hydrogen Peroxide Citric Acid Reaction System and Its Application in Wet Mixing of Natural Rubber Latex

ABSTRACT To enhance the surface activity of pyrolysis carbon black (CBp), decrease surface impurity content, improve interfacial bonding, and dispersion in natural rubber, a green modification method was developed using hydrogen peroxide (H 2 O 2 ) as an oxidant and biodegradable citric acid as the acidic reaction system. Moreover, the filler dispersion, Payne effect, vulcanization characteristics, mechanical properties, and dynamical properties of modified CBp/natural rubber (NR) composites prepared by a novel twin‐screw shear dewatering process were evaluated. XRD, FTIR, and contact angle results showed that when CBp was modified by H 2 O 2 in the citric acid system, the surface impurity content decreased, and hydrophilicity, dispersion, and surface activity improved. The CBp/NR by H 2 O 2 /citric acid modification combined with the twin‐screw shear dewatering process had the best overall performance. Compared to unmodified CBp/NR, the tensile strength, resilience, and abrasion resistance were improved by 18.4%, 19.0%, and 46.6%, respectively, and the rolling resistance was reduced by 65.2%, providing a new method for the high‐value green recycling application of CBp in high‐quality natural rubber composites.