To develop an orthopedic material for bone substitution, the substitute material must mimic living tissue from an anatomical and physiological point of view. The high wear and impact resistance besides the low friction coefficient, make ultra-high molecular weight polyethylene (UHMWPE) a suitable material to be used in orthopedic applications. However, UHMWPE is a bioinert material, not providing a proper interaction with the bone tissue surrounding to the implant. One way to mitigate this issue is improving UHMWPE bioactivity. This can be done by adding bioactive fillers in the polymeric matrix. In this work, UHMWPE composites were prepared by twin-screw extrusion. The fillers used were carbonated hydroxyapatite (CHA) and hybrids formed by precipitating CHA in collagens (hydrolyzed and type II). The results show that the fillers used caused a slight reduction in UHMWPE crystallinity degree, while both crystallization and melting temperatures remained almost unchanged. Dynamic-mechanical thermal analysis indicated a weak adhesion between filler and polymeric matrix, which is good from the biological point of view since the bioactive filler surface will be available to apatite deposition. The obtained materials exhibited good mechanical properties and in vitro bioactivity assay showed that all of the prepared materials are bioactive.

为了开发用于骨替代的骨科材料，替代材料必须从解剖学和生理学的角度模拟活体组织。除低摩擦系数外，高耐磨性和耐冲击性使超高分子量聚乙烯（UHMWPE）成为骨科应用的合适材料。但是，UHMWPE是一种生物惰性材料，无法与植入物周围的骨组织提供适当的相互作用。缓解此问题的一种方法是提高UHMWPE的生物活性。这可以通过在聚合物基质中添加生物活性填料来完成。在这项工作中，UHMWPE复合材料是通过双螺杆挤出制备的。使用的填充剂是碳酸化羟基磷灰石（CHA）和通过在胶原蛋白中沉淀CHA形成的杂化物（水解和II型）。结果表明，所用的填料导致UHMWPE结晶度略有降低，而结晶和熔融温度几乎保持不变。动态机械热分析表明填料与聚合物基体之间的附着力较弱，从生物学的角度来看这是良好的，因为生物活性填料表面可用于磷灰石沉积。所获得的材料表现出良好的机械性能，并且体外生物活性测定表明，所有制备的材料均具有生物活性。