The Research On Performances Of Graphene Oxide Reinforced Ultra-high Molecular Weight Polyethylene Composites

Ultra-high molecular weight polyethylene (UHMWPE), which has good wearresistance, high impact toughness, excellent corrosion resistance and biocompatibility,has been widely used as the artificial joint materials with a combination of metal orceramic. However, owing to the low surface hardness and poor wear resistance ofpolymer, the UHMWPE will produce polyethylene wear particles, which will causebone loss, joint loosening, discomfort, and ultimately limits the lifespan of the joints.In this thesis, graphene oxide (GO) was prepared using a modified Hummers'method and then dispersed in ethanol by ultrasonic treatment to get the stable solutionof GO. The morphology and structural of the prepared GO was characterized byseveral methods. The results showed the GO exhibited a typically wrinkled, thin andsheet-like structure with the size of several microns and thickness of about2-4nm.Infrared spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopycharacterization indicated that the GO had carboxyl, hydroxyl, epoxy and otheroxygen functional groups. The GO/UHMWPE composites were prepared byliquid-phase ultrasonication dispersion followed by hot-pressing. Results showed thatGO sheets were embedded into the polymer so that GO and polymer could combinetightly to each other to form a layered structure; the crystallinity of the compositesincreased with the addition of GO; the addition of1.0wt.%GO increased themicrohardness of about15%and the composite with GO content of0.5wt.%hadexcellent tensile performance; compared with pure UHMWPE, the friction coefficientof the GO/UHMWPE composite increased while the wear rate decreased, and thewear rate of composite decreased by about35%when the GO content of1%;moreover, the addition of GO sheets into UHMWPE had no negative effect on the cellgrowth and the cells well adhered and proliferated on the GO/UHMWPE surface withthe increase of the culture time. Therefore, the combined advantages of theGO/UHMWPE composites, including improved mechanical properties and goodbiocompatibility, make them promising materials for artificial joints applications.