POSS grafted hybrid-fabric composites with a biomimic middle layer for simultaneously improved UV resistance and tribological properties

Poor interfacial adhesion and inferior UV resistance severely inhibit the development of hybrid Meta-aramid/Polytetrafluoroethylene (Nomex/PTFE) fabric composites for distinguished solid self-lubrication materials, especially under high exterior load and long-term UV irradiation conditions. Herein, glycidyl polyhedral oligomeric silesquioxanes (POSS) nanoparticles are covalently grafted onto the hybrid Nomex/PTFE fabric with a polydopamine/polyethylenimine (PDA/PEI) intermediate layer. The microstructure and chemical characteristics of Nomex and PTFE fibers before and after modification are investigated and the results manifest an obvious increase in surface functional groups and roughness, as well as resin compatibility. Tensile and peeling testing results show that the obtained fabric composites, denoted as hybrid-fabric@PDA/PEI-POSS composites, exhibit 24.3% and 46.8% enhancements in tensile and interfacial bonding strength without discernable decrease in pristine hybrid-fabric strength. In addition, the PDA/PEI-POSS hierarchical coating imparts the hybrid-fabric with excellent UV-shielding properties. As a result, the tribological performance of hybrid-fabric@PDA/PEI-POSS composites presents an obvious improvement under high load and UV irradiation conditions.