UHMWPE Composite Materials for Joint Implants

描述(申请人提供)：在这个SBIR第一期项目中，超高分子量聚乙烯(UHMWPE)关节植入材料的关键机械性能将通过创造一种含碳增强的复合材料来改善。超高相对分子质量聚乙烯(UHMWPE)长期以来一直被广泛应用于关节植入物中，通过交联聚乙烯链进一步提高了其耐磨性。然而，交联过程也与机械性能的退化有关，包括韧性、疲劳和屈服强度。通过上述方式在UHMWPE中加入碳增强材料将在不影响其低磨损率的情况下提高UHMWPE的强度和抗蠕变性能。如果碳和聚合物之间发生了良好的负载转移，碳增强材料将为UHMWPE基质提供无与伦比的尺寸稳定性和韧性。这些假设将通过在不同形成条件下制备复合材料、使试件在不同的交联化条件下进行，然后评估其机械和摩擦学性能来验证。如果新的UHMWPE材料的表现符合预期，其好处将包括更持久的植入物，更不容易发生灾难性的失败。 公共卫生相关性：关节植入物是治疗类风湿性关节炎、骨关节炎、骨坏死和其他严重破坏性损伤的有效方法；仅在美国，每年就有大约50万例关节置换手术。随着预期寿命的增加，患者的寿命往往会超过其植入物的10至15年的寿命。这个项目将引入一种新材料，可以用来制造寿命更长的假肢。

DESCRIPTION (provided by applicant): In this SBIR Phase I project the key mechanical properties of ultrahigh molecular weight polyethylene (UHMWPE) joint implant materials will be improved by creating a composite material with carbon reinforcements. UHMWPE has long been widely used in joint implants, and further improvements to its wear resistance have been obtained by cross-linking the polyethylene chains. However, the cross-linking process has also been associated with degradation of the mechanical properties, including toughness, fatigue and yield strengths. Incorporating carbon reinforcements into UHMWPE through the manner described will improve the strength and creep resistance of UHMWPE without compromising its low wear rate. The carbon reinforcements will impart unmatched dimensional stability and toughness to the UHMWPE matrix, providing that good load transfer occurs between the carbon and polymer. These hypotheses will be validated by preparing composite materials under various formation conditions, subjecting test specimens to various crosslinking conditions, and then assessing their mechanical and tribological properties. Should the new UHMWPE materials perform according as expected, the benefits would include longer-lasting implants that are less prone to catastrophic failure. PUBLIC HEALTH RELEVANCE: Joint implants are an effective treatment for those with rheumatoid arthritis, osteoarthritis, osteonecrosis, and other severe destructive injuries; within the U.S. alone, roughly 500,000 joint replacements are performed each year. As life expectancy increases, patients more frequently outlive the 10 to 15 year lifetime of their implant. This projet will introduce a new material from which prosthetics with longer lifetimes can be fabricated.