Preparation and properties of multiwall carbon nanotubes/carbon foam composites

•Carbon foams can be prepared by direct pyrolysis of cyanate ester (CE) resin.•Multiwall carbon nanotubes (MWCNTs) are suitable nanofillers in the carbon foams.•The MWCNTs/carbon foam composites possess good mechanical strength.•Their bulk density increases but porosity decreases with increasing WMCNTs content.

Multiwall carbon nanotubes (MWCNTs)/carbon foam composites were prepared by direct pyrolysis of MWCNTs/cyanate ester (CE) resin mixtures. Pyrolysis behavior of the MWCNTs/CE resin mixtures was characterized by thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and X-ray diffraction (XRD). In addition, physical and mechanical properties of the resultant pyrolysis products were studied. Results show that the pyrolysis products are the MWCNTs/carbon foam composites with an amorphous structure. The addition of WMCNTs results in an increase in the density of the composites and a decrease in their porosity. Moreover, the compressive strength of the composites as well as their thermal conductivity and electrical conductivity increase with an increase in the additive amount of WMCNTs from 0 to 1.0 wt.%.