聚乳酸/氧化石墨烯纳米复合材料的结构与性能

Structure Characterization and Properties of Polylactic Acid/Graphene Oxide Nanocomposites

以鳞片石墨为原料通过改良的Hummers方法制备氧化石墨烯(GO)。以GO为助剂,采用熔融共混法制备了聚乳酸(PLA)/GO纳米复合材料。通过X射线衍射、扫描电子显微镜、透射电子显微镜对PLA/GO纳米复合材料的结构进行了表征,并对其力学性能和结晶度进行了测试。微观结构分析表明,GO呈现剥离状,并均匀分散在PLA基质中;力学性能研究表明,1%GO的加入有助于改善PLA复合材料的断裂伸长率;断面扫描电镜分析表明PLA复合材料断面发生明显改变,呈现出韧性断裂特征;差示扫描量热结果显示GO可以消除PLA基质冷结晶,有助于提高PLA复合材料结晶度,与X射线衍射分析相吻合。

Graphene oxide( GO) was prepared by the modified Hummers method. Polylactic acid( PLA)/GO nanocomposites were prepared with GO through melting processing. The structure of PLA/GO nanocomposites was characterized by XRD,SEM and TEM. Moreover,the mechanical properties and crystallinity of PLA/GO nanocomposites were studied. The microstructure shows that GO appears at exfoliated or partially intercalated nanometer layers,and TEM shows that GO is evenly dispersed into the PLA matrix in the form of exfoliated layers. The mechanical properties shows that the elongation at break of PLA nanocomposites is improved when the loading content of GO is 1%. SEM analysis demonstrates that a visible transformation takes place in the section morphology which manifests the toughness of PLA based nanocomposites; DSC results display that GO eliminates the cold crystallization process,and obviously promotes the crystallinity,which is in accordance with the result of XRD analysis.