Geng Jingqi, Cai Yingchun
Key Laboratory of Bio-Based Material Science and Technology of Ministry of Education, School of Material Science and Engineering, Northeast Forestry University, Harbin 150040, China.
Materials (Basel). 2024 Apr 12;17(8):1779. doi: 10.3390/ma17081779.
Natural fiber/degradable epoxy composites have received much attention for their advantages of low carbon emissions, low environmental pollution, and utilization of renewable resources. However, the poor interfacial bonding strength and inferior moisture resistance of natural fiber/degradable epoxy composites restrict their application areas. In order to improve the moisture and heat resistance of natural fiber/degradable epoxy resin-based composites, this study modified the surfaces of ramie fibers with hydroxylated carbon nanotubes, silane coupling agents, and sodium hydroxide, respectively. Three types of modified ramie fiber/degradable epoxy composites, namely F-CN-DEP, F-Si-DEP, and F-OH-DEP, were prepared using a winding forming process. The water absorption rate and short-beam shear strength of the materials were tested under different environments, and the fiber morphology and thermal-mechanical properties of the materials were investigated by scanning electron microscopy (SEM) and dynamic mechanical analysis (DMA). The results show that F-CN-DEP exhibited the lowest moisture absorption rate; the highest shear strength, of 43.8 MPa; and a glass transition temperature () of 121.7 °C. The results demonstrate that carbon nanotubes on the fiber surface can improve the interfacial stability of ramie fiber/degradable epoxy composites in humid and hot environments. These results give guidelines for the development of natural fiber/degradable epoxy composites.
天然纤维/可降解环氧树脂复合材料因其具有低碳排放、低环境污染以及可再生资源利用等优点而备受关注。然而，天然纤维/可降解环氧树脂复合材料较差的界面结合强度和耐湿性限制了它们的应用领域。为了提高天然纤维/可降解环氧树脂基复合材料的耐湿热性能，本研究分别用羟基化碳纳米管、硅烷偶联剂和氢氧化钠对苎麻纤维表面进行改性。采用缠绕成型工艺制备了三种改性苎麻纤维/可降解环氧树脂复合材料，即F-CN-DEP、F-Si-DEP和F-OH-DEP。测试了材料在不同环境下的吸水率和短梁剪切强度，并通过扫描电子显微镜（SEM）和动态力学分析（DMA）研究了材料的纤维形态和热机械性能。结果表明，F-CN-DEP的吸湿率最低；剪切强度最高，为43.8MPa；玻璃化转变温度（）为121.7℃。结果表明，纤维表面的碳纳米管可以提高苎麻纤维/可降解环氧树脂复合材料在湿热环境下的界面稳定性。这些结果为天然纤维/可降解环氧树脂复合材料的开发提供了指导。
