Epoxy composites reinforced with multi-walled carbon nanotube/poly(ethylene glycol)methylether-coated aramid fiber

Abstract

A novel type of aramid fibers coated with poly(ethylene glycol) methyl ether (PEGME)-modified multi-walled carbon nanotubes (MWCNTs) was designed using electrophoresis. Owing to the good interaction of MWCNT-PEGME with the matrix, the coated fibers were well dispersed in epoxy resin. Thin films of epoxy/aramid-MWCNT-PEGME were prepared by placing the modified aramid fibers in molds, and the epoxy resin was infused into them. 4,4′-Diaminodiphenylmethane was dissolved in epoxy before the resin was poured over the aramid fibers coated with MWCNT-PEGME. According to fracture surface studies, the modified fibers were completely miscible with the epoxy resin and the filler was dispersed well in the space between the aramid fibers. The tensile strength of neat resin was increased from 658 to 1198 MPa in 40 wt.% of fiber-loaded epoxy/aramid-MWCNT-PEGME 40 composite. The maximum flexural strength was also found to be higher for epoxy/aramid-MWCNT-PEGME 40 (1593 MPa). The glass transition temperature (Tg) was studied using differential scanning calorimetry, in the range of 164-173°C. The tensile strength, modulus, flexural strength, and Tg of epoxy/aramid fiber composites with unmodified fibers were found to be lower than those of epoxy/aramid-MWCNT-PEGME composites.