Fabrication and characterization of functionally graded synthetic graphite/phenolic nanocomposites

Stepwise functionally graded synthetic graphite/phenolic nanocomposites (FGNs) were fabricated using combined powder stacking and compression molding techniques. The process allowed the fabrication of FGNs with four different microstructure gradient patterns of the same geometry and graphite content, as well as non-graded nanocomposites (NGNs). The FGN with the highest graphite content layer on the top and bottom surfaces and the lowest in the center, showed the highest improvement of 97% in thermo-mechanical properties and the best creep recovery of 34.7% among all FGNs and NGN. Introducing graphite by 20 wt% increased thermal conductivity of phenolic from 0.35 to 0.88 W/(m degrees C) and decreased its electrical resistivity to 20.8 Omega/cm. It was found that the electrical and thermal properties of nanocomposites could be manipulated by changing the gradient patterns. (C) 2012 Elsevier B.V. All rights reserved.