聚乳酸/氧化石墨烯纳米复合材料的界面调控与性能研究

Interface Control and Performance of Polylactide/Graphene Oxide Nanocomposites

分别以乙二胺(EDA)、十二烷基胺(DA)和十八烷基胺(ODA)修饰的氧化石墨烯(GO)为填料,制备了具有不同界面结构的功能化聚乳酸(PLA)/氧化石墨烯(FGO)纳米复合薄膜。采用X射线衍射分析、扫描电子显微镜、热失重分析、差示扫描量热法对复合薄膜的材料结构、微观形貌和热性能进行表征,并研究了其力学性能及气体渗透性。结果表明,随着GO表面接枝分子链的增长,复合材料的热稳定性、力学性能及气体阻透性能提高;3种FGO中,GO-g-ODA改性体系的综合性能最佳,当其添加量为0.5%(质量分数,下同)时,复合材料的拉伸强度和断裂伸长率分别达到88.52 MPa和9.68%;氧气渗透系数由原来的4.21×10^(-13) cm^3cm/(cm^2·s·Pa)下降到1.172×10^(-14) cm^3cm/(cm^2·s·Pa),约下降了97.2%;此外,功能化石墨烯的加入使复合材料的热稳定性提高。

Graphene oxide (GO) was functionalized with ethylenediamine (EDA), dodecylamine (DA) and octadecylamine (ODA), and then the nanocomposite films based on polylactide(PLA) and functionalized GO were prepared by a hot pressing method. The structure, morphology and thermal properties ofnanocomposite films were characterized by XRD, SEM, TGA and DSC, and their mechanical properties and oxygen resistance were investigated. The results indicated that the mechanical and thermal properties and oxygen resistance of nanocomposite films were improved with an increase of the length of surface-grafted molecular chain. GO-g-ODAwas found to have a much better modification effect on the nanocomposite films than GO-g-EDA and GO-g-DA. The nanocomposite films achieved the maximumtensile strength and elongation at break of 88.52 MPa and 9.68 % at the GO-g-ODA content of 0.5 wt %, and their oxygen permeability coefficient decreased by 97.2 % from 4.21×10^-13 to 1.172×10^-14 cm^3cm/(cm^2·s·Pa). In addition, the thermal stability of PLA was also improved in the presence of functionalized GO.