基于火焰法碳纳米材料的玻璃钢界面强化机理研究

GFRP composites in the hydraulic and marine industry are prone to brittle fracture in the presence of complicated external forces, mainly in the form of delamination between the plies due to the weakening of the fiber/matrix interface. As a result, it is urgent to promote the fiber/matrix adhesion for GFRP. Different from the common used method that the surface treatment of glass fibers with variant coupling agents，a kind of flame-synthesized carbon nanomaterials possessing unique surface characteristics were coated on the surface of fibers for the interface enhancement of GFRP, which effectively improved the integrated mechanical properties in the previous work. However, its enhancing mechanism is still unclear, which limits the broader application of this new method for interface enhancement of GFRP. In the work, the microscopic morphologies, solidification microstrutures, mechanical properties and fracture behaviors of GFRP interfacial modified with different flame-synthesized carbon nanomaterials would be characterized and measured with scanning electron mocroscopy (SEM), impact test, Dynamic mechanical analysis (DMA) test, et al to compare their interface enhancement effects for GFRP. Meanwhile, the surface atomic structures of different flame-synthesized carbon nanomaterials would be characterized with modern micro-characterization techniques to establish the atomic model for them. After that, combinng the ab-initio, molecular dynamics simulation with the contact angel measurement, the surface properties of different flame-synthesized carbon nanomaterials would be evaluated. Through establishing an association between the surface properties of flame-synthesized carbon nanomaterials and their interface enhancement performance for GFRP, the interface enhancing mechanism of GFRP with flame-synthsized carbon nanomaterials would be revealed. This work would provide theoretical basises for application of flame-synthesized carbon nanomaterials in the interface enhancement of GFRP, which improves its intergrated mechanical property to better meet the requirements of hydraulic and marine structures.

水工和海工结构用玻璃钢受复杂外应力作用时，内部玻纤/树脂界面易于产生剥离分裂导致材料脆性破坏，须改善其界面粘结性。不同于常规的以偶联剂处理玻纤表面的方法，前期工作中将一种具有独特表面特性的火焰法碳纳米材料包覆到玻纤表面以增强玻璃钢界面，界面粘结效能显著提升。目前此界面强化机理还不甚明了，限制了该方法的应用。本项目拟通过SEM、冲击和DMA测试等手段对不同火焰法碳纳米材料改性界面的玻璃钢的微观形貌、固化结构、力学性能和断口形貌进行表征测试以对比其界面强化效果；采用现代微观表征技术表征不同火焰法碳纳米材料的表面原子结构并建模，利用第一性原理等方法计算模拟并结合接触角测试评估其表面特性；将不同火焰法碳纳米材料的界面强化效果与其表面结构特性相关联，揭示火焰法碳纳米材料对玻璃钢的界面强化机理。本项目将为火焰法碳纳米材料增强玻璃钢界面以优化其综合力学性能，使玻璃钢更好地适应水工和海工要求提供理论依据。

水工和海工结构用玻璃钢受复杂外应力作用时，内部玻纤/树脂界面易于产生剥离分裂导致材料脆性破坏，须改善其界面粘结性。不同于常规的以偶联剂处理玻纤表面的方法，前期工作中将一种具有独特表面特性的火焰法碳纳米材料包覆到玻纤表面以增强玻璃钢界面，界面粘结效能显著提升。目前此界面强化机理还不甚明了，限制了该方法的应用。.本项目将火焰法纯碳纳米管、氮掺杂碳纳米管、螺旋碳纳米纤维以及石墨烯应用到玻璃钢界面改性，系统研究了研究玻璃钢界面改性工艺和玻璃钢成型参数对界面增强效果的影响，确定并完善了一种利用具有独特表面特性的火焰法碳纳米材料改善玻璃钢力学性能的界面增强方法。从微结构表征、机械性能测试、断口分析和理论计算等方面系统地研究了火焰法碳纳米材料对玻璃钢的界面增强机理。研究结果表明，不同火焰法碳纳米材料对玻璃钢界面增强效果表现为火焰法氮掺杂碳纳米管>火焰法螺旋碳纳米纤维>火焰法石墨烯>火焰法纯碳纳米管>化学气相沉积法(CVD)碳纳米管，这主要归因于火焰法氮掺杂碳纳米管由于表面既具有-COOH和-CH2OH等氧化官能团，同时又具有C-N，C=N，C≡N等极性键，表面碳原子结构发生扭转以及倒置情况最为显著，使得石墨层产生几何弯曲的能量最高，化学反应活性大大增加，即不同种类火焰法碳纳米材料表面结构特性具有的表面能大小所导致其在玻璃钢界面上的均匀分散性和结合力是决定其对玻璃钢界面增强效果的关键因素。本项目研究成果为优化玻璃钢力学性能使其更好地适应水工和海工结构要求提供了新方法和理论依据。