A modified spray-winding approach to enhance the tensile performance of array-based carbon nanotube composite films

A carbon nanotube (CNT) array based spray-winding approach for CNT film fabrication was developed by adding a post hot-pressing process, and an epoxy solution was used to fabricate CNT/epoxy composite film. It showed that the hot-pressing process benefited the load transfer within CNT films by reducing the porosity among CNT bundles and was more efficient in improving the tensile properties of few wall CNT films. The epoxy modified multi-wall CNT film exhibited a tensile strength and modulus of 1540 MPa and 59 GPa, respectively. From the results of scanning electron microscopy and measurements of contact angle, Raman spectroscopy and thermogravimetric analysis, the main mechanism of the improvement was attributed to good wettability of CNT film with epoxy, high degree of CNT alignment, and high CNT load in the CNT film.