Construction of carbon fiber-carbon nanotube reinforcing phase and mechanical properties of its three-phase composites

Abstract

The carbon nanotube (CNT)-polyetherimide (PEI) was successfully grafted onto the surface of carbon fibers (CF) through chemical grafting method for constructing a CF-g-CNT reinforcing phase. Results show the construction of CF-g-CNT fiber can effectively improve the interface, impact resistance and bending properties of the composites. Considering the effect of strengthening phase on the mechanical properties of composites, the interfacial shear strength, impact strength, flexural modulus and flexural strength of CF-g-CNT/BMI composites respectively increase by 48.8%, 10.8%, 5.2% and 14.6%, companed with those of CF/BMI. In addition, the interfacial shear strength, impact strength, flexural modulus and flexural strength of CF-g-CNT/BMI-PEI-CNT composites are 56.9%, 27.1%, 12.5% and 16.1% higher than those of CF/BMI-PEI-CNT, respectively. The interfacial shear strength, impact strength, flexural modulus and flexural strength of CF-g-CNT/BMI-PEI-CNT composites increase by 57.7%, 33.7%, 20.0% and 23.7% compared with CF/BMI. The CNT-PEI in CF-g-CNT can effectively change the interface composition and change the expansion path of horizontal stress or vertical stress at the interface, which is beneficial to disperse the stress concentration as well as improve the mechanical properties of the composites.

Keywords

• cnts
• carbon fiber
• chemical grafting
• mechanical property