Evolution of anisotropic bubbles and transition of the mechanical and electrical properties during a non-continuous two-step foaming of epoxy/carbon nanofiber composites

A non-continuous two-step foaming process was reported to prepare microcellular epoxy/carbon nanofiber (EP/CNF) composite foams. This approach involved firstly limited-foaming epoxy tablets in a mold with a fixed cavity to obtain preformed foams with designed anisotropic cellular structure and following by free-foaming them in a heating oven. The evolution of cell morphology, rearrangement of carbon nanofibers, and changes of the mechanical and...