Towards tough, yet stiff, composites by filling an elastomer with single-walled nanotubes atvery high loading levels

Abstract

We have used recent advances in nanotube dispersion technology to prepare composites based onpolyurethane, with mass fractions of up to 80% polyethylene glycol functionalized nanotubes.Mechanical testing shows increases in Young’s modulus compared to polyurethane films by up to800 ×. While the composite strength did not vary significantly withnanotube content, the ductility and so the toughness fell by a factor of240 × onaddition of ∼40 wt% nanotubes. Depending on the nanotube content we can produce films ranging fromthe stiff and brittle at high nanotube loading to the compliant and ductile at low nanotubevolume fraction.