Rheological properties and fracture toughness of epoxy resin/multi‐walled carbon nanotube composites

Abstract

Multi‐walled carbon nanotubes (MWCNTs), surface‐treated via chemical functionalization, i.e., oxidation and amidation, were used to reinforce diglycidylether of bisphenol F (DGEBF) epoxy resin. The effects of the functionalization on the dispersion stability, rheological properties, and fracture toughness of DGEBF/MWCNT composites were investigated. The dispersion homogeneity of the MWCNTs in the epoxy matrix improved after functionalization. In addition, isothermal rheology measurements revealed that the DGEBF/dodecyl amine‐functionalized MWCNT (D‐MWCNT) composite had a longer gel time and higher activation energy of cross‐linking than the DGEBF/acid‐treated MWCNT (A‐MWCNT) composite. The fracture toughness of the former was also significantly higher than that of the latter; this resulted from the relatively high dispersion stability of the D‐MWCNTs in the epoxy matrix, owing to the presence of alkyl groups on the D‐MWCNT surface. POLYM. ENG. SCI., 55:2676–2682, 2015. © 2015 Society of Plastics Engineers

Use of Carbon Nanotubes to Improve Fracture Toughness of Polymer Concrete

“…Investigations of the fracture toughness of epoxy polymer systems have typically been limited to reporting on the critical stress intensity factor (K Ic ) as the fracture toughness parameter (3,(17)(18)(19)(20)(21). The vast majority of literature investigations showed an increase in the fracture toughness of epoxy as a result of the inclusion of MWCNTs (3,4,9,15,(17)(18)(19)(20)(21)(22)(23)(24)(25); further improvement was shown as the MWCNT content increased (2,3,17,23,24). However, Ma et al and Opelt et al showed a decrease of K Ic with an increase in the content of pristine MWCNTs (10,25).…”