医用镁表面L-聚乳酸与MgO或Mg（OH）2复合涂层的制备与性能

摘要

对医用镁可降解高分子基复合材料表面改性技术进行了探索研究，以提高镁在生理环境下的耐蚀性及其表面的生物相容性。采用环氧氯丙烷-丙酮混合溶剂在高纯镁上制备了 L-聚乳酸(PLLA)涂层，再分别以MgO和Mg(OH)2为增强相，制备了PLLA基复合涂层。使用扫描电镜、耐蚀性快速检测、涂层/基体结合力测试、电化学动电位极化曲线测量以及体外生物降解行为研究对涂层进行综合分析。结果表明，适量 MgO 或Mg(OH)2增强相的添加均能显著提高PLLA涂层在Hank’s模拟体液中的降解防护性能，并有利于降低 PLLA 生物降解所产生的酸化效应。%The surface modification of magnesium alloys by bio-degradable polymer matrix composites for biomedical applications was studied to improve both corrosion resistance and surface biocompatibility of magnesium under physiological conditions. A poly(L-lactic acid) (PLLA) coating was formed on high-purity magnesium substrate with epichlorohydrin and acetone as solvent, and two PLLA matrix composite coatings were prepared with MgO and Mg(OH)2 as reinforcement respectively. The comprehensive performances of the coatings were evaluated by scanning electron microscopy, rapid corrosion resistance test, coating/substrate adhesion test, potentiodynamic polarization measurement, and in vitro biodegradation behavior studies. The results showed that adding an appropriate amount of MgO or Mg(OH)2 as reinforcement can improve the resistance of PLLA coating to degradation in Hank’s simulated body fluid, and reduce the acidification during the dissolution of PLLA.