玄武岩纤维/环氧树脂复合材料的界面强化与力学性能研究

Study on Interface Strengthening and Mechanical Properties of Basalt Fiber/Epoxy Resin Composites

本文通过手工铺层和热压制备了一种具有多尺度增强的环氧树脂(EP)复合材料。首先,利用不同质量分数的硅烷偶联剂(KH560)改性玄武岩纤维(BF),并采用浸渍法将羧基化多壁碳纳米管(CNT)接枝到改性BF的表面上,以实现BF/CNT对复合材料的多尺度增强。傅里叶变换红外光谱(FTIR)和X射线光电子能谱(XPS)表明KH560成功接枝到BF表面。扫描电子显微镜(SEM)表明,BF/CNT增强复合材料的树脂黏附性更好,界面相互作用更强。研究发现KH560的质量分数是实现CNT固定化和复合材料良好力学性能的重要因素。在KH560的最佳质量分数(5%)下,由于更有效的载荷传递,复合材料(BF-5%KH560-CNT/EP)的拉伸强度、弯曲强度和层间剪切强度分别为637.82 MPa、1519.94 MPa、105.27 MPa,与未改性复合材料相比分别提高了12.51%、20.93%和25.55%。

Epoxy resin(EP)composites with multiscale reinforcements were prepared by hand lay-up and hot-pressing.Firstly,basalt fiber(BF)was modified by silane coupling agent(KH560)with different mass fraction,and carboxylated multi-walled carbon nanotubes(CNTs)were grafted onto the surface of the modified BF by immersion method to achieve multi-scale reinforcement of BF/CNTs on the composite.Fourier transform infrared spectroscopy(FTIR)and X-ray photoelectron spectroscopy(XPS)show that KH560 is successfully grafted onto the BF surface.Scanning electron microscopy(SEM)indicates better resin adhesion and thus a stronger interfacial interaction is in the BF/CNTs-reinforced composite.It is observed that the mass fraction of KH560 is a significant parameter in achieving good CNT immobilization and good mechanical properties of the composites.At the optimum mass fraction of KH560(5%),the tensile,flexural and interlaminar shear strengths of the composite(BF-5%KH560-CNT/EP)are 637.82 MPa,1519.94 MPa and 105.27 MPa respectively,which are increased by 12.51%,20.93%and 25.55%comparing with the unmodified composite due to more effective load transfer.