Effects of block copolymer dispersant and nanotube length on reinforcement of carbon/epoxy composites

The epoxy matrix of a carbon fiber/epoxy composite was modified with multiwall carbon nanotubes (MWCNTs) to improve the matrix dominated thermomechanical properties of the composite. Effects of improved dispersion and nanotube length on reinforcement of the composite were investigated experimentally. The dispersion of the CNTs was enhanced with a block copolymer. Two different CNT lengths, 1 and 10 μm on average, were considered. Irrespective of the length, a pronounced improvement of the composite properties was achieved with 0.5 wt% of MWCNTs with the use of block copolymer. Without the block copolymer, it was found that a higher enhancement of composite properties was achieved with the longer nanotubes.