Biomimetic surface modification of UHMWPE fibers to enhance interfacial adhesion with rubber matrix via constructing polydopamine functionalization platform and then depositing zinc oxide nanoparticles

Aimed at enhancing the interfacial adhesion property of ultrahigh molecular weight polyethylene (UHMWPE) fibers reinforced rubber composites, a biomimetic surface modification strategy was put forward by constructing polydopamine (PDA) functionalization platform and then depositing zinc oxide nanoparticles (nano-ZnO). Inspired by the mechanism of mussel adhesion, a layer of PDA film was coated onto the fiber surface by dopamine oxidative self-polymerization reaction. Subsequently, through the coordination interaction between nano-ZnO and PDA, the deposition of nano-ZnO was realized. The results of characterization analysis, including fiber surface morphologies, chemical compositions and structures, not only confirmed the process of the proposed modification but also elucidated the interactions among UHMWPE, PDA and nano-ZnO. The H-pull test showed that the maximum H-pull force of modified UHMWPE fibers to rubber matrix was up to 34.3 N, increased by 85.4% compared with that of pristine UHMWPE fibers, which could be mainly attributed to the combined action of interfacial physicochemical interactions and mechanical interlocking. Moreover, it was found that the reaction time should be controlled to avoid the degradation of adhesion due to excessive modification.