Facile dispersion of aramid pulp by matrix sizing agent and reinforced rubber composites

Abstract The properties of Kevlar fiber‐reinforced composites strongly depend on the dispersion homogeneity of the fiber in matrix and their adhesion. Dispersing fibers into a rubber is more challenging than using traditional fillers, especially for aramid pulp (AP) with a highly branched structure. Herein, we reported a facile pre‐dispersion method to disperse AP in rubber and to enable efficient reinforcement. AP was firstly modified using dopamine to enhance the surface characteristics, and then the modified AP was dispersed in a solution of nitrile‐butadiene rubber (NBR) in ethanol, followed by drying to obtain the AP pre‐dispersion. This pre‐dispersion was incorporated into NBR by a traditional rubber processing method to produce composites. The measurements of Fourier transform infrared, optical and electric microscopies, X‐ray photoelectron spectroscopy, and dynamic mechanical analysis on the composites demonstrate that surface modification using dopamine and the pre‐dispersion method obviously improved the AP dispersabiligy and the interfacial interaction between the pulp and NBR, resulting in the enhanced mechanical and oil‐resistance properties of the composites.