Spatial dispersion state of carbon nanotubes in a freeze-drying method prepared carbon fiber based preform and its effect on electrical conductivity of carbon fiber/epoxy composite

摘要

This paper first studied the spatial dispersion state of carbon nanotubes (CNTs) in different positions of a freeze-drying method prepared carbon fiber/CNTs preform. The results demonstrated that continuous CNT networks could be assembled within each fiber bundle, while between fiber bundles and in interlaminar space, only large CNT sheets with certain thickness were observed. Despite these, the electrical conductivity along different directions of the freeze-drying method prepared composite was significantly improved, which was associated with the optimization of spatial dispersion of CNTs in the whole preform and composite. Relationship between electrical performances of composite and spatial dispersion state of CNTs was also discussed.