Composites of MWCNTs and an organically modified partially synthetic layered silicate (OMLS) with PC/ABS were prepared by melt blending and the relationship between morphology and electric properties as a function of composite composition examined. The concept of double percolation was investigated and confirmed, as a consequence of CNT preferential segregation within one polymer phase (PC). A role of OMLS in hindering the formation of an effective electrically conductive network was observed above a certain clay loading, resulting in a shifting of electrical percolation threshold towards higher values. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012