Interfacial Interactions and Mechanical Properties of Natural Rubber Composites Reinforced With FA @Sucrose‐Derived Carbon Core‐Shell Particles

ABSTRACT

Fly ash (FA) is an abundant aluminosilicate solid waste whose high surface polarity limits its reinforcing efficiency in natural rubber (NR). Herein, a polyacrylamide (PAM)‐induced interfacial assembly strategy was developed to fabricate sucrose‐derived carbon‐coated FA core‐shell particles (FA@SDC). PAM acted as an interfacial transition layer, promoting stable sucrose adsorption through hydrogen‐bonding interactions and enabling the in situ formation of a continuous carbon shell during carbonization. Multiscale characterizations demonstrated that PAM enhanced sucrose loading and regulated the carbon‐shell content and structural ordering, with FA‐P‐C ₆ exhibiting the optimal core‐shell structure. After incorporation into NR, the carbon shell effectively bridged the hydrophilic FA and hydrophobic rubber matrix, improving filler dispersion, strengthening filler‐rubber interfacial interactions, facilitating stress transfer, and reducing interfacial thermal resistance. Consequently, the FA‐P‐C ₆ composite exhibited the best overall performance, with tensile strength, tear strength, and wear resistance increasing by 15.86%, 21.81%, and 16.42%, respectively, while thermal conductivity and thermal diffusivity increased by 13.42% and 13.93%, respectively. This work establishes a structure‐interface‐property relationship for PAM‐induced FA@SDC and provides a simple, green, and effective strategy for the high‐value utilization of fly ash in high‐performance rubber composites.