Electrical conductivity of multi-walled carbon nanotubes-SU8 epoxy composites

We have characterized the electrical conductivity of the composite which consists of multi-walled carbon nanotubes dispersed in SU8 epoxy resin. Depending on the processing conditions of the epoxy (ranging from non-polymerized to cross-linked), we obtained tunneling and percolating-like regimes of the electrical conductivity of the composites.

(a) Results of conductivity measurements (symbols) for CNT-SU8 composites with non-polymerized epoxy (N-P), with polymerized (P), and with polymerized hard-baked sample (P-B). The solid lines are least square fits of the conductivity data to the theory. (b) Conductivity plotted on a log-log scale: the P and P-B composites display a power-law behavior as φ → 0. (c) Conductivity on a log scale plotted as a function of 1/φ: the N-P composites follows the tunneling behavior with D2/ξL = 0.019.

Claudio Grimaldi, Marijana Mionic, Richard Gaal, Laszlo Forro, and Arnaud Magrez

APPLIED PHYSICS LETTERS 102, 223114 (2013)