Highly efficient mussel-like inspired modification of aramid fibers by UV-accelerated catechol/polyamine deposition followed chemical grafting for high-performance polymer composites

Abstract A facile and efficient mussel-like inspired modification method was developed to improve the interfacial adhesion of aramid fibers/rubber composites. The surfaces of aramid fibers were pre-deposited by poly(catechol/polyamine) (PCPA) layer, which was formed via the oxidation polymerization of catechol/polyamine (CPA) under UV irradiation. Then, the PCPA-coated fibers were further grafted with ethylene glycol diglycidyl ether (EGDE) to introduce epoxy groups onto aramid fibers surface. The kinetics of catechol oxidation was investigated by UV–vis measurements, suggesting that UV irradiation accelerated the polymerization process of CPA. The effects of EGDE concentration and grafting time on the adhesion force between aramid fibers and rubber matrix were evaluated by pull-out test, and a maximum increase of 85.6% in adhesion force was achieved, even better than that by dopamine in our previous study (a 67.5% improvement). Compared with the method based on dopamine chemistry, this method has advantages of lower cost (less than 1% of the price of dopamine) and shorter reaction time (3 h less in pre-deposition time). This study provides a new efficient strategy for fibers surface functionalization, which has promising application in rubber industry.