Abstract: In order to improve the comprehensive properties of glass fiber reinforced epoxy composites (GFRE), industrial multi-walled carbon nanotubes (MWCNTs) were dispersed uniformly in EP by adding dispersant B60T, and then glass fiber reinforced epoxy composites containing MWCNTs (MWCNTs/GFRE) were fabricated. The effects of functional groups and content of MWCNTs on the macro and micro mechanical properties of GFRE were further studied, and the interfacial adhesion of the composites was also evaluated. The results showed that functionalized MWCNTs can significantly improve the mechanical properties and interlaminar bonding strength of GFRE, and the hydroxylated MWCNTs (MWCNTs-OH) has the most obvious improvement in mechanical properties and interlaminar shear strength (ILSS) of GFRE. When the addition amount of MWCNTs-OH was 0.1wt%, the tensile strength and flexural strength of MWCNTs-OH/GFRE were increased by 51.9% and 31.2%, respectively, the tensile modulus and flexural modulus were improved by 9.1% and 5.2%, respectively, and the ILSS was raised by 23.9%, as compared with pure GFRE composites. Dynamic viscoelastic studies showed that the initial storage modulus (E′) and the glass transition temperature (T_g) of MWCNTs-OH/GFRE were increased by 10.1% and 4.8 ℃ compared with GFRE, respectively. The increase of interfacial adhesion and temperature resistance of MWCNTs/GFRE is suggested to be related to the content and type of functional groups of MWCNTs, the difficulty of reaction with epoxy molecule and the freedom of chemical bonds formed between MWCNTs and EP.

Key words: composite, glass fiber, epoxy resin, multi-walled carbon nanotubes, mechanical property