Increasing fiber volume fraction results in an increase in thermal conductivity. However, this increase is not significant enough to make the VGCF composites particularly useful thermally conductive materials.
The large surface area of the VGCF inhibits resin infusion.
The top table provides mechanical information for VGCF/epoxy composites prepared using high speed blender mixing.
Increasing fiber volume fraction results in an increase in thermal conductivity (bottom graph); however, this increase for the fibers utilized in this program is not significant enough to make the VGCF composites particularly useful thermally conductive materials. The slope for the experimental data straight line approximation was much lower than the rule of mixture equation. As the rule of mixture slope is a product of two non-measurable parameters, the fiber efficiency parameter and the fiber thermal conductivity, the parameter causing the lower thermal conductivity can not be determined from these experiments. Due to the small size of the fiber, it is probable that the large number of thermal transfers between the fiber and the matrix inhibit thermal flow through the composite which would lower the fiber efficiency.