基于碳纳米管复合纤维预制体的复合材料结构和性能

Investigation on structure and properties of composites based on carbon nanotubes-containing preform

通过合成碳纳米管(CNTs)上浆剂、制备纳米复合纤维预制体、RTM成型和固化等工艺过程,将CNTs引入到连续纤维增强环氧树脂复合材料中。采用万能电子试验机、动态力学分析仪(DMA)、扫描电镜等分析测试手段,对混杂多尺度复合材料的弯曲性能、层间剪切强度、玻璃化转变温度(Tg)和微观结构进行测试和表征。结果表明,与不含CNTs的复合材料相比,引入CNTs的混杂多尺度复合材料的弯曲性能和层间剪切强度均提高50%以上。混杂多尺度复合材料的玻璃化转变温度提高至200℃。复合材料断口的扫描电镜观察表明,CNTs复合表面涂层处理能够松弛玻璃纤维增强体表面的应力集中,通过"桥联"作用提高了CNTs混杂复合材料的力学性能。

The hybrid multiscale composites were fabricated via preparing carbon nanotubes （ CNTs ）-containing sizing and nanocomposite preform followed by resin transfer molding （RTM） processing.The flexural properties,interlaminar shear strength （ ILSS） , glass transition temperatures （ Tg ） and microstrctrue of the hybrid composites containing varying scale reinforcements were measured and characterized,respectively.It is demonstrated that, compared to the primary specimen,the flexural properties and ILSS of preform specimen increase more than 50% due to the incorporation of CNTs,and Tg of the hybrid composites is up to 200℃. Reduction in the stress concentration on the surface of glass fiber induced by CNTs reinforced epoxy coating is shown in scanning electron microscopy （ SEM） of the fracture of CNTs hybrid composites to identify the bridging mechanism for improving the mechanical properties.