| 초록 |
The electrical conductivity of MWCNTs/polymer composite films are strongly affected by the Bernard-Marangoni (B-M) instability during solvent evaporation. B-M instability occurs when the thermal Bernard-Marangoni number is higher than a critical number. We investigated three types of conditions; unstable, onset, and stable. We modifed the expression of percolation scailing law where the Bernard-Marangoni cell is taken into account. The modified percolation scailing law could be written as log(Rs0/Rs)=log(cβ-c0)t. The exponent t was found to be 2.0, indicating the MWCNTs/polymer composite films exhibit three-dimensional behavior in percolation scaling law in spite of the B-M instability occurs. The value of β was found to be 1.0, 1.2, and 0.8 at stable, onset, and unstable condition, respectively. The percolation threshold for PC/MWCNT composite films at stable, onset, and unstable condition is 3.30×10-3, 2.75×10-3, and 5.15×10-3 vol.%, respectively. |
