Composites made from IM7 and carbon nanofibers (fiber type PR-24-HHT at 16 wt% loading) showed a 70% increase in thermal conductivity.
First table: In-plan shear strength and shear modulus measured at 22oC determined from a composite with a [+/- 45] configuration. With this specimen configuration the layers fail in a scissoring fashion such that failure is forced to occur between plies. Increase in shear strength of 13% for Pr-24-PS-Ox noticed when compared to baseline. Shear modulus is approximately 15% higher.
Second table: Compression strength and modulus of IM7/Nanocomposites. Compression strength is driven primarily by Euler bucking of fiber so if the matrix modulus is increased, the composite compressive strength will be increased. Average strength for the PR-24-PS-OX and PR-24-HHT composites is somewhat higher than the baseline.
Third table: Thermal diffusivity and thermal conductivity of IM7/Nanocomposites.
Fourth table: Comparison of thermal diffusivity and thermal conductivity of PR-24-HHT in Epon 862/W.
Thermal conductivity was determined through the Z-axis using the thermal flash method. Thermal conductivity was then calculated using appropriate values for density and heat capacity. A 25% improvement in thermal conductivity for the PR-24-PS-OX and PR-24-PS-NS-LD (nitro) composites was observed. The composite with PR-24-HHT fibers had a 50% improvement over the baseline which is quite significant. A 70% increase in thermal conductivity was found for the 16 wt% loaded sample of PR-24-HHT. Expected payoff is not as high as might be expected given the poor dispersion of nanofibers throughout the composite.