Surface-conductive UHMWPE fibres via in situ reduction and deposition of graphene oxide

Abstract

Surface-conductive ultra-high molecular weight polyethylene (UHMWPE) fibres were prepared via in situ reduction and deposition of graphene oxide (GO). GO was dispersed in water to form a uniform and stable suspension. Subsequently, GO was chemically reduced into rGO and spontaneously deposited onto gel-spun, ultra-drawn UHMWPE fibres. The UHMWPE was coated with polydopamine (PDA), emulating the surface coating in mussels, prior to the rGO deposition to improve the bonding between rGO and the fibre surface. Characterizations using SEM, EDX, FTIR and XPS confirmed the effectiveness of the PDA coating and rGO deposition and the covalent bonding between PDA and rGO. The electrical resistance of UHMWPE-PDA-rGO decreased monotonically with increasing GO percentage in the suspension and deposition cycle. The UHMWPE-PDA-rGO exhibited an electrical resistance of 105 Ω/cm, whereas UHMWPE and UHMWPE-PDA showed a resistivity of >1012 Ω/cm. Using Ag deposited UHMWPE-PDA as the benchmark, UHMWPE-PDA-rGO was superior in durability, conductivity and retention of ultrahigh tensile properties. Analysis using the TGA data and linear density confirmed the partial reduction of GO during processing. Furthermore, a plausible log-log linear relationship was revealed between the resistance and the weight ratio of UHMWPE-PDA + GTGA and pure UHMWPE-PDA (χ), which tentatively explained the deposition mechanisms.