EFFECTS OF COMPOUNDING SET-UP ON ELECTRICAL CONDUCTIVITY PROPERTIES OF CARBON BLACK FILLED COMPOUNDS

摘要

Conductive carbon black is commonly used to permanently modify the electrical properties of plastic compounds from insulating to conductive. Some applications require a high degree of dispersion; for example, thin sheets for electronic packaging, cable semicons or electrically conductive pipes do not tolerate undispersed carbon black. In this article we investigate three compounding routes via twin screw extruder showing how incorrect setups can dramatically decrease the quality of the final compounds. We also show that poor carbon black feeding or very high melt viscosity of concentrated compounds (like masterbatch) can have detrimental effects on the electrical properties. Finally, we show that the degree of dispersion is strongly dependent not only on the melt viscosity but also on the carbon black selected.