The effect of bernard-marangoni convection on percolation threshold in amorphous polymer-multiwall carbon nanotube composites

The electrical conductivity of amorphous polymer/multiwall carbon nanotube (MWCNT) composite films strongly depends on the Bernard-Marangoni (B-M) instability during solvent evaporation. We demonstrate that the films exhibit the lowest surface resistivity and the highest light transmittance near the onset point of B-M instability. The polymer/MWCNT composite films exhibit three-dimensional behavior in spite of the B-M instability. The percolation threshold for PC/MWCNT composite films at stable, onset, and unstable condition is 3.3 × 10−3, 2.75 × 10−3, and 5.15 × 10−3 vol.%, respectively.

► Electrical conductivity of polymer/MWCNT films depends on a Marangoni instability. ► The films show the highest conductivity near the onset point of the instability. ► The films show the highest transparency near the onset point of the instability. ► The films are three-dimensional in percolation scaling in spite of the instability.