Nusbaum H J, Rose R M
J Biomed Mater Res. 1979 Jul;13(4):557-76. doi: 10.1002/jbm.820130404.
The effects of radiation sterilization on ultrahigh molecular weight polyethylene were explored by freeze fractures, electron spin resonance, absorption of aqueous media, density measurements, small-angle and wide-angle x-ray scatter, differential scanning calorimetry, infrared and ultraviolet-visible spectrometry, static and dynamic mechanical fatigue measurements, and standard environmental stress cracking measurements. The rate of fluid absorption increased significantly due to the appearance of carbonyl groups. As the fluids were absorbed, density increased and small-angle x-ray scatter (SAXS) intensity diminished slightly, as expected. Small changes in mechanical properties (e.g., tensile properties and dynamic spectrum) were always consistent with the cross-linking which occurs after irradiation; the only significant mechanical deterioration was in the fatigue properties. The nonspherulitic, inhibited crystallinity which characterized this material and which is responsible for its excellent static resistance to environmental stress cracking was not at all changed.
通过冷冻断裂、电子自旋共振、水性介质吸收、密度测量、小角和广角X射线散射、差示扫描量热法、红外和紫外可见光谱法、静态和动态机械疲劳测量以及标准环境应力开裂测量，探究了辐射灭菌对超高分子量聚乙烯的影响。由于羰基的出现，流体吸收速率显著增加。正如预期的那样，随着流体被吸收，密度增加，小角X射线散射（SAXS）强度略有降低。力学性能的微小变化（如拉伸性能和动态谱）始终与辐照后发生的交联一致；唯一显著的力学性能劣化在于疲劳性能。这种材料所具有的非球晶、受抑制的结晶度使其具有出色的静态耐环境应力开裂性，而这种结晶度完全没有改变。
