The role of carbon nanofiber defects on the electrical and mechanical properties of CNF-based resins.

Heat treatment of carbon nanofibers has proven to be an effective method in removing defects from carbon nanofibers, causing a strong increase in their structural perfection and thermal stability. It affects the bonding states of carbon atoms in the nanofiber structure and causes a significant transformation in the hybridization state of the bonded carbon atoms.Nanofilled resins made of heat-treated CNF show significant increases in their electrical conductivity even at low concentrations.

Cure behavior and physical properties of epoxy resin-filled with multiwalled carbon nanotubes.

Different experimental procedures were investigated for incorporating Multi walled Carbon nanotubes (MWCNT) into epoxy diglycidil-ether bisphenol-A (DGEBA), cured with 4,4' diamine-dibenzyl-sulfone (DDS): (i) mechanical mixing for either 60 or 120 minutes; (ii) high energy ball milling for 30 minutes; (iii) ultrasonication for 20 minutes. The mechanical properties of the obtained samples were monitored and used in order to guide the selection of the most promising composite system. The best results were obtained by using, as method of incorporation of carbon nanotubes in the resin, sonication for 20 minutes.