Wei Jiajia, Peng Shigui, Xue Bin, Yang Zhao, Qin Shuhao, Yu Jie, Xu Guomin
Department of Polymer Material and Engineering, College of Materials and Metallurgy, Guizhou University Guiyang 550025 China
National Engineering Research Center for Compounding and Modification of Polymer Materials Guiyang 550014 China.
RSC Adv. 2019 Jul 15;9(38):21903-21910. doi: 10.1039/c9ra02479d. eCollection 2019 Jul 11.
In this work, a simple and eco-friendly strategy to modify graphene nanoplatelets (GNs) with different silane coupling agents using a supercritical carbon dioxide (Sc-CO) process has been presented, and effect of the modified GNs on the oxygen transmission rate (OTR) and water vapor transmission rate (WVTR) of GN/PET composite films was studied. FT-IR, SEM, EDX and TG results indicated that Sc-CO process was an effective strategy to modify GNs with silane coupling agents. Addition of the modified GNs into PET matrix could greatly decrease the OTR and WVTR values of the GNs/PET composite films, and the WVTR of GNs560/PET composite film and OTR of GNs550/PET composite film were respectively decreased about 90.08% and 58.04%, as compared to those of GNs/PET composite film. It is found that the gas barrier property of GN/PET composites was attributed to not only the tortuous path effect caused by GNs themselves and the interfacial interaction, but also the affinity of binding bonds between GNs and the polymer to the gas molecules. It is believed that this work provided a strategy to design and prepare CN/polymer composites with high barrier properties.
在本工作中，提出了一种使用超临界二氧化碳（Sc-CO₂）工艺用不同硅烷偶联剂修饰石墨烯纳米片（GNs）的简单且环保的策略，并研究了改性GNs对GN/PET复合膜的氧气透过率（OTR）和水蒸气透过率（WVTR）的影响。傅里叶变换红外光谱（FT-IR）、扫描电子显微镜（SEM）、能谱分析（EDX）和热重分析（TG）结果表明，Sc-CO₂工艺是用硅烷偶联剂修饰GNs的有效策略。将改性GNs添加到PET基体中可大幅降低GNs/PET复合膜的OTR和WVTR值，与GNs/PET复合膜相比，GNs560/PET复合膜的WVTR和GNs550/PET复合膜的OTR分别降低了约90.08%和58.04%。研究发现，GN/PET复合材料的气体阻隔性能不仅归因于GNs自身引起的曲折路径效应和界面相互作用，还归因于GNs与聚合物之间结合键对气体分子的亲和力。相信这项工作为设计和制备具有高阻隔性能的CN/聚合物复合材料提供了一种策略。
