High strength composites using interlocking carbon nanotubes in a polyimide matrix

Polyethylene was crystallized on carbon nanotubes (CNTs) resulting in the formation of nanosheets on the surface. The material was then carbonized in sulfuric acid at 20 C for 24 h, resulting in a carbon shish-kebab (CSK) structure. Incorporating the CSKs in polyimide (PI) matrix produced a uniform dispersion in which interactions between the nodules producing an interlocking effect that significantly improved the load transfer between the matrix and the CNTs. Consequently, the CSK/PI composite showed a 27% increase in tensile strength, compared to one using pristine CNTs, and 100% increase in the strain compared to the pure PI membrane.