超高分子量聚乙烯(Ultra High Molecular Weight Polyethylene,简称UHMWPE)是一种具有低摩擦,低磨耗的热塑性工程塑料,作为承载材料用于人工关节臼杯已有五十年的历史,临床上目前主要应用于人工髋关节,膝关节和腕关节,与金属合金或者陶瓷关节球头配合使用。在人体生理冲击加载条件下,UHMWPE关节臼杯表面固有的机加工缺陷在人体关节所特有的多向力运动下,经长期磨损之后会产生大量细小的磨屑,从而诱发巨噬细胞产生一系列不良生理反应,释放溶骨因子,导致固定和配合良好的人工关节发生无菌松动,最终失效。由无菌松动所导致的人工关节失效比例占到其失效比例的50%以上,因此,可以认为磨损是人工关节失效的主要原因。由此可以看出,降低UHMWPE的磨损率,提高UHMWPE关节臼杯的承载能力是提高人工关节使用寿命的关键所在。
辐照交联可以有效地提高UHMWPE的耐磨性,但辐照后材料部分力学性能下降,抗压向载荷的能力减弱,尤其是在空气辐照条件下,力学性能的下降和材料氧化老化现象更为明显。为避免空气中氧气对材料制备的影响,将真空热压成型,真空包装辐照及真空熔融热处理引入材料制备过程,采用纳米填充...
【英文摘要】
Ultra high molecular weight polyethylene (simplified as UHMWPE) is a type of thermoplastic with low friction coefficient and wear loss. It has been used as bearing materials of artificial joints for fifty years. It has been clinically applied on hip, knee and wrist joints, articulated against metallic or ceramic joint. Due to the intrinsic defects on the wear surface, a large amount of wear debris will be generated, when the bearing surface of UHMWPE cup endures multidirectional wear motion under physiologi...