镁/聚乳酸复合材料的制备与表征

Preparation and Characterization of Mg/PLA Composite

为有效中和聚乳酸降解过程后的酸性,提出镁颗粒与聚乳酸的复合材料新体系。采用造粒-注塑工艺制备了3%Mg/聚乳酸(PLA)复合材料,通过扫描电镜(SEM)、X射线衍射(XRD)等手段表征了产物的微观形貌与物相组成;测试了力学性能;采用模拟体液浸泡手段研究了复合材料的降解行为。结果表明,采用造粒、注塑工艺可以制备这类复合材料,少量镁颗粒的加入对聚乳酸的力学性能影响不明显,其中拉伸强度和延伸率分别下降了6%和12.5%,但弯曲强度有所增加。聚乳酸降解后的酸性得到了有效的中和,聚乳酸浸泡30 d后的pH值为6.28,而3%Mg/PLA复合材料浸泡30 d后的pH值仅为6.85。

To effectively neutralize the acidic during the degradation of poly lactide acid（PLA）,Mg/PLA composites were proposed and 3% Mg/PLA composites were prepared using granulation combines injection molding process.The morphology and phase constitute of Mg/PLA composites were analyzed by means of scanning electron microscopy（SEM） and X-ray diffraction（XRD）.The simulated body fluid（SBF） was used to study the degradation behavior of Mg/PLA composites.The results show that,Mg/PLA composites can be successfully fabricated by granulation and injection molding process.Compared with pure PLA,the tensile strength and elongation of Mg/PLA composites decrease by 6% and 12.5% respectively,but the bending strength increases at some extents.The addition of magnesium particles can effectively neutralize the acidic during PLA degradation.After one month immersion,the pH value of PLA solution decreases to 6.28 however that of Mg/PLA composites only decreases to 6.85.