Effect of polymer matrix on rheological and electrical percolation threshold of MWCNTs

Abstract

In this work,polymer nanocomposites of polystyrene-b-polybutadiene-b-polystyrene (SBS), atriblock copolymer, and multi-walled carbon nanotubes (MWCNTs)wereproduced by melt mixing. MWCNTs contents between 0 and 10% (v/v) were used to produce the SBS/MWCNTs nanocomposites. Electrical conductivity of these materials was measured and compared with polystyrene (PS)/MWCNTs nanocomposites with the same MWCNTs loadings. The results showed that electrical percolation thresholdofSBS/MWCNTs was 0.9% (v/v) and 3.5% for PS/MWCNTs. The rheological percolation thresholdat temperature of the processing 150°C, was also reduced from 3.5% for PS to 1.1% for SBS. These results suggested that SBS copolymer matrixhad a better affinity with MWCNTs, which was confirmed by transmition electron microscopyimages (TEM), whichshowed a better dispersion of the MWCNTs in SBS than in PS matrix.