Maintaining reliability remains a great challenge for ultrahigh molecular weight polyethylene (UHMWPE) bearings due to oxidation in biological environments. This work aimed at inspecting the efficacy of the hybrid antioxidant strategy in stabilizing crosslinked UHMWPE under an in vitro clinically relevant accelerated aging condition. The hybrid antioxidant system was composed of vitamin E (VE) and D-sorbitol (DS) as primary and secondary antioxidants, respectively. The already established in vitro clinically relevant accelerated aging was performed via squalene absorption and subsequent thermal oxidation treatment. Compared to the use of VE alone, the combination of VE and DS significantly protracted the oxidation induction time of UHMWPE with no apparent oxidation after aging, showing a notable synergistic effect on the oxidative stability of UHMWPE. The crosslink density was higher for VE/DS/UHMWPE than VE/UHMWPE at each aging period. It revealed that the hybrid antioxidant strategy settled the longstanding contradiction between oxidation stability and crosslinking of UHMWPE. Attributed to improved oxidation stability, there was a positive reversal in the tensile property between VE/DS/UHMWPE and VE/UHMWPE after aging, where comparable ultimate tensile strength and higher elongation at break were observed. These findings underline the high potential of the hybrid antioxidant strategy for developing artificial joint materials with desired ability to resist oxidation and balanced performance.

由于生物环境中的氧化，保持可靠性对于超高分子量聚乙烯 (UHMWPE) 轴承来说仍然是一个巨大的挑战。这项工作旨在检验混合抗氧化剂策略在体外临床相关加速老化条件下稳定交联 UHMWPE 的功效。混合抗氧化系统由维生素 E (VE) 和 D-山梨糖醇 (DS) 分别作为主要和次要抗氧化剂组成。已经在体外建立通过角鲨烯吸收和随后的热氧化处理进行临床相关的加速老化。与单独使用VE相比，VE和DS的组合显着延长了UHMWPE的氧化诱导时间，且老化后无明显氧化现象，对UHMWPE的氧化稳定性表现出显着的协同作用。在每个老化阶段，VE/DS/UHMWPE 的交联密度高于 VE/UHMWPE。结果表明，混合抗氧化策略解决了 UHMWPE 氧化稳定性和交联之间长期存在的矛盾。由于氧化稳定性提高，老化后 VE/DS/UHMWPE 和 VE/UHMWPE 之间的拉伸性能发生正向逆转，观察到相当的极限拉伸强度和更高的断裂伸长率。