为研究玻璃纤维对聚脲性能的影响,分别以聚脲和玻璃纤维作为基体和增强体,合成了玻璃纤维/聚脲复合材料。通过扫描电子显微镜、傅里叶变换红外光谱仪和动态热机械分析仪,探究玻璃纤维长度在0.2～0.8mm、添加量在0.5%～1.5%(wt,质量分数,下同)范围时对复合材料微观结构、力学性能和动态力学性能的影响规律,分析复合材料的耗能机理。结果表明:玻璃纤维在基体中分布均匀,降低了复合材料的氢键化程度、氢键结合强度以及微相分离程度;复合材料的拉伸强度、撕裂强度随玻璃纤维长度和添加量的增加而提高,当玻璃纤维长度为0.8mm、添加量为1.5%时,复合材料的拉伸强度为30.14MPa,撕裂强度为127.48kN/m,力学性能最好;随着玻璃纤维长度和添加量的增加,复合材料的储能模量和损耗模量逐渐增加,玻璃化转变温度向高温移动;复合材料的主要耗能机理为本征阻尼和界面阻尼,本征阻尼随着玻璃纤维长度的增加而减小,界面阻尼随着玻璃纤维添加量的增加而增大。

In order to study the effect of glass fiber on the properties of polyurea,glass fiber/polyurea composites were synthesized with polyurea as matrix and glass fiber as reinforcement.With the help of scanning electron microscopy (SEM),Fourier transform infrared spectroscopy (FT-IR) and dynamic thermomechanical analysis (DMA),etc.,the effects of glass fiber length in the range of 0.2～0.8mm and addition amount in the range of 0.5%～1.5% on the microstructure,mechanical properties and dynamic mechanical properties of composite materials were investigated.The energy dissipation mechanism of the composites was also analyzed.The results showed that the glass fiber was evenly distributed in the matrix,which reduced the degree of hydrogen bonding,hydrogen bonding strength and microphase separation of the composites.The tensile strength and tear strength of the composites increased with the increase of fiber length and addition amount.When the fiber length was 0.8mm and the addition amount was 1.5%,the tensile strength and tear strength of the composites were 30.14MPa and 127.48kN/m,respectively,exhibiting the best mechanical properties.With the increase of the length and amount of glass fiber,the storage modulus and loss modulus of the composites increased gradually,and the glass transition temperature moved to high temperature.The main energy dissipation mechanisms of composites were intrinsic damping and interfacial damping.The intrinsic damping decreased with the increase of glass fiber length,and the interfacial damping increased with the increase of fiber addition.