Conductivity and Mechanical Properties of Composites Based on MWCNTs and Styrene-Butadiene-Styrene BlockTM Copolymers

摘要

Composites based on multiwall carbon nanotubes (MWCNTs) and the block copolymer styrene-butadiene- styrene with two different contents of styrene have been investigated and their electrical conductivity and mechanical properties have been evaluated. The composites were prepared by a solution casting procedure, using a dispersant agent for the MWCNTs. Conductivity values of 10 4 and 1.6 S cm 1 have been obtained for samples containing 1 and 12 wt % of MWCNTs, respectively. The percolation threshold achieved for these systems was 0.25 wt %. According to dynamic mechanical analysis, the MWCNTs interact with both phases of the copolymers, acting as a reinforcement filler, whereas the dispersant agent acts as a plasticizer. However, it was shown that the reinforcing effect of the MWCNTs overcomes the latter, resulting in an overall improvement of mechanical properties of the composites.