Lewis G, Carroll M
Department of Mechanical Engineering, The University of Memphis, Memphis, TN 38152-3180, USA.
Biomed Mater Eng. 2001;11(3):167-83.
The in vitro quasi-static tensile and compressive creep properties of three sets of GUR 1050 ultra-high-molecular-weight polyethylene (UHMWPE) specimens were obtained. These sets were: control (as-received stock); "low-gamma" (specimens were crosslinked using gamma radiation, with a minimum dose of 5 Mrad); and "high-gamma" (specimens were crosslinked using gamma radiation, with a minimum dose of 15 Mrad). The % crystallinity (%C) and crosslink density (rho(x)) of the specimens in the three sets were also obtained. It was found that, in both tension and compression, crosslinking resulted in a significant depreciation in the creep properties, relative to control. The trend in the creep results is explained in terms of the impact of crosslinking on the polymer's %C and rho(x). The present results are in contrast to literature reports that show that crosslinking enhances the wear resistance of the polymer. The implications of the present results, taken together with the aforementioned literature results, are fully discussed vis-a-vis the use of crosslinked UHMWPE for fabricating articular components for arthroplasties.
获得了三组GUR 1050超高分子量聚乙烯（UHMWPE）试样的体外准静态拉伸和压缩蠕变性能。这三组分别是：对照组（原样库存）；“低伽马”组（试样采用伽马辐射交联，最小剂量为5兆拉德）；以及“高伽马”组（试样采用伽马辐射交联，最小剂量为15兆拉德）。还获得了这三组试样的结晶度百分比（%C）和交联密度（ρ(x)）。结果发现，在拉伸和压缩过程中，相对于对照组，交联导致蠕变性能显著下降。根据交联对聚合物%C和ρ(x)的影响来解释蠕变结果的趋势。目前的结果与文献报道相反，文献报道表明交联可提高聚合物的耐磨性。结合上述文献结果，全面讨论了目前结果对于使用交联UHMWPE制造关节置换术关节部件的意义。
