Simultaneously Enhancing the Processability and Wear Resistance of UHMWPE Through Tiny Graphene Dispersion

The entanglement degree of ultra-high molecular weight polyethylene (UHMWPE) exhibits an inverse correlation with its rheological properties and wear resistance, creating a fundamental challenge in simultaneously enhancing melt processability while preserving superior anti-wear performance. The fabrication of polymer nanocomposites with reasonable structure is expected to solve this intractable problem. Graphene has excellent wear resistance and can reduce the viscosity of polymers. Therefore, we prepared a series of UHMWPE/Graphene composites in this paper. The effects of graphene on the microstructure, rheological behavior, crystallization behavior, and wear resistance of UHMWPE were investigated by transmission electron microscopy, small-angle x-ray scattering, dynamic mechanical analysis, and differential scanning calorimeter characterization methods, and hence the rheological and wear mechanisms of the composites were analyzed. The results show the optimized composite with 0.4 wt% graphene demonstrates remarkable performance synergies: a 68% reduction in complex viscosity and a 4.5-fold enhancement in wear resistance (the specific wear rate decreased from 2.45 × 10 −4 to 0.56 × 10 −4 mm 3 /N m). This work establishes a materials design paradigm for overcoming the intrinsic property trade-offs in UHMWPE, particularly relevant for applications demanding both processability and durability.