Enhanced Mechanical and Anti‐Hydroplaning Properties of Natural Rubber via Polydopamine‐Carbon Nanotube Modified Hollow Microspheres

ABSTRACT Hollow microspheres (RiM03), as a novel inorganic filler, exhibit excellent dispersibility in rubber matrices and significantly reduce the overall weight of rubber composites. However, their smooth surface and poor mechanical interlocking result in reduced mechanical strength and limited anti‐hydroplaning capability, thereby restricting their practical applications. This study proposed a composite filler based on polydopamine (PDA)‐coated RiM03 decorated with multi‐walled carbon nanotubes (MWCNTs). The abundant catechol groups on the PDA coating promoted π–π stacking interactions with MWCNTs, enhancing the filler's dispersion and interfacial adhesion within the natural rubber matrix. The structure–property relationship was systematically evaluated using composites with varied MWCNT loadings of 0, 0.5, 1, 1.5, 2, and 3 phr. The composite containing 2 phr MWCNTs (NR‐2) exhibited optimal performance: compared to (NR‐0), tensile strength increased by 53.6%, tear strength improved by 44.8%, and abrasion resistance enhanced by 27.1%. The peak tanδ value at 0°C increased markedly, suggesting enhanced damping behavior and wet traction capability. This study provides a novel approach for engineering interfaces in rubber composites and offers new insights for designing sustainable materials with outstanding performance under dynamic wet conditions.