Research Progress on Carbon Black in Wet Compounding of Natural Rubber: Modification and Processes

ABSTRACT This research presents a thorough review of the use of carbon black in the wet mixing of natural rubber, including the basic features of natural rubber latex and carbon black, as well as carbon black reinforcing methods. This paper reviews the current research progress, analyzes the action mechanisms, advantages and disadvantages of mainstream carbon black modification methods, along with the technical characteristics and industrialization potential of two types of wet mixing processes, which are non‐full‐formulation and full‐formulation. Research has indicated that several major difficulties remain unresolved, first, the appropriate degree of carbon black oxidation is unknown. Second, in the full‐formulation process, it's difficult to achieve simultaneous mixing of sulfur and accelerators. Therefore, this research presents multiple modification options to improve carbon black dispersion and interfacial compatibility, such as oxidation combined with grafting and oxidation combined with activators. To resolve the conflict between scorch and dehydration in the full‐formulation system, it is proposed to optimize the twin‐screw structure to achieve efficient dehydration at low temperatures. Furthermore, the research discusses a technical strategy, which combines multiple modification, mixing, and twin‐screw extrusion; it's expected to promote the practical application of carbon black/natural rubber latex wet‐mixing technology.