Effect of carbon nanotubes on thermal conductivity and mechanical performance of carbon foam derived from mesophase pitch

Modified carbon nanotubes (m-CNTs) were dispersed uniformly in the mesophase pitch by ultrasonic dispersion. Then carbon foam was prepared through self volatile foaming, carbonization and graphitization using m-CNTs/mesophase pitch compound as a precursor. TEM, SEM analysis methods were employed to investigate the amount of additional m-CNTs on the structure and properties of the carbon foam. The results show that the dispersion of m-CNTs was improved when comparing with CNTs. The average size of carbon foam reduced to some degree when m-CNTs are added, furthermore the number of micro-cracks of the foam decreased significantly. When the proportion of the m-CNTs reaches 5wt%, thermal conductivity and compression strength of carbon foam achieve the highest, 137 W/(m·K) and 12.1 MPa, respectively.