Carbon-Nanomaterial-Reinforced Spread-Tow Carbon fiber/polypropylene composites

Polypropylene (PP) films reinforced with multi-walled carbon nanotubes (MWCNTs) and exfoliated graphite nanoplatelets (xGnPs) were fabricated by extrusion, and the effects of filler type and take-up speed on the mechanical properties and microstructure of composite films were investigated. Multiscale hybrid composites consisting of unidirectional spread-tow carbon fibers (UDCF) and PP films reinforced with MWCNT and xGnP were manufactured by hot pressing, and the tensile and flexure tests and differential scanning calorimetry were performed to measure the mechanical properties and the degree of crystallinity, respectively. In parallel, modeling and simulation of CNM/PP composite films and CNM/UDCF/PP hybrid composites were carried out to predict the tensile properties taking into account the effects of CNM orientation. The mechanical properties of composites were most dominantly affected by the degrees of polymer crystallinity and CNM dispersion as well as CNM alignment.