Surface Modification of Aramid Fibers by Catechol/Polyamine Codeposition Followed by Silane Grafting for Enhanced Interfacial Adhesion to Rubber Matrix

In this work, we develop a modified mussel-inspired method to enhance interfacial adhesion of aramid fiber to a rubber matrix. Through a simple dip-coating procedure, catechol and polyamine could initially codeposit as a poly(catechol-polyamine) (PCPA) coating on the surface of the aramid fiber. Then, the PCPA layer could be further grafted with silane coupling agent γ-(glycidyloxypropyltrimethoxysilane) (GPTMS). Results indicated that GPTMS was successfully grafted onto the aramid fiber surface via the bridging of the PCPA layer. The interfacial adhesion between the aramid fibers and the rubber matrix was improved compared to that achieved by polydopamine in our previous study. In addition, this method is more applicable to the rubber industry than polydopamine coating because of its cost-effectiveness and short reaction time.