Lan Zhenbo, Deng Jiangang, Xu Zhuolin, Ye Zhu, Nie Yu
Wuhan Nari Limited Liability Company of State Grid Electric Power Research Institute, Wuhan 430000, China.
State Grid Electric Power Research Institute, Nanjing 210000, China.
Polymers (Basel). 2023 Jun 19;15(12):2734. doi: 10.3390/polym15122734.
In this paper, mechanical properties of the diglycidyl ether of bisphenol A epoxy resin (EP) reinforced with a 20% fiber glass (GF) with layered structure after high temperature aging are studied. Tensile and flexural stress-strain curves of the GF/EP composite after aging tests in the temperature range of 85-145 °C in air were measured. Tensile and flexural strength demonstrate gradual decrease with the increase in the aging temperature. The failure mechanism at the micro scale is studied by the scanning electron microscopy. A separation of the GFs and EP matrix and evident pullout of the GFs are observed. Degradation of the mechanical properties is explained by a cross-linking and chain scission of the initial molecular structure of the composite and decrease in the interfacial adhesion force between GFs and EP matrix caused by oxidation of the EP matrix and difference of the GF and EP coefficients of thermal expansion.
本文研究了高温老化后具有层状结构的20%玻璃纤维（GF）增强双酚A环氧树脂（EP）二缩水甘油醚的力学性能。测量了在85-145°C空气中进行老化试验后GF/EP复合材料的拉伸和弯曲应力-应变曲线。拉伸强度和弯曲强度随老化温度的升高而逐渐降低。通过扫描电子显微镜研究了微观尺度下的失效机制。观察到GF与EP基体分离以及GF明显拔出。力学性能的下降是由于复合材料初始分子结构的交联和断链，以及EP基体氧化和GF与EP热膨胀系数差异导致GF与EP基体之间界面附着力降低所致。
