Processing and morphological development of carbon black filled conductingblends using a binary host of poly(styrene co-acrylonitrile) and poly(styrene)

The effects of host/filler interactions, processing, and morphological deve lopment of low percolation threshold (Phi (c)) conducting blends were inves tigated. It was found that the value of Phi (c) was dramatically reduced by the isolation of the carbon black (CB) conducting filler at the cocontinuo us interface of a binary poly(styrene) (PS) and poly(styrene co-acrylonitri le) (SAN) insulating host, resulting in a multiple percolation effect. Accu mulation of the filler at the interface was possible due to the incompatibi lity of the CB filler with the PS phase and partial compatibility with the SAN phase. The best results were obtained by initially dispersing the CB in the PS phase during melt-blending, followed by the addition of the SAN pha se. (C) 2000 John Wiley & Sons, Inc.