Thermal, Electrical, and Mechanical Properties of Epoxy/Carbon Powder/Carbon Nanotube Composites
Mainstream Engineering Corporation, US
Keywords: carbon nanotubes, composites, conductivity, mechanical properties
Abstract:Carbon nanotubes (CNT) are used for their excellent properties to enhance the corresponding properties of polymer-based nanocomposites. Property expectations are often set by reference to the CNT – single-walled nanotubes (SWNT), for instance, are expected to excel in mechanical and electrical properties while multi-walled nanotubes (MWNT) excel in thermal conductivity. Functionalized CNT are expected to give better mechanical properties than pristine CNT. However, empirical data on epoxy-based nanocomposites confound this simple picture. For instance, the data indicate that MWNT are more effective than SWNT at strengthening despite their lower intrinsic strength. The effects of functionalization can also be surprising, sometimes improving electrical conduction and other times degrading it. The relative effectiveness of MWNT and SWNT at enhancing thermal conductivity is even less clear. In light of the complexity of property predictions, it is unwise to measure a single property and assume that improvements will map onto other properties. This presentation will more fully confront property interrelationships in little-understood epoxy nanocomposites containing both CNT and conventional carbon fillers. These relationships will be used to probe questions like: which CNT - if any – is best in multifunctional nanocomposites? Can remaining gaps be filled by other fillers, and how will the two fillers interact?