Morphology evolution during manufacture and extrusion of polypropylene/graphite nanoplates vomposites

This work monitors the evolution of the dispersion of two commercial grades of graphite nanoplates during compounding with PP in a co-rotating twin screw extruder, followed by processing in a single screw extruder. Both machines are fitted with sampling ports, so that samples can be collected along their axes and subsequently characterized. Most of the dispersion takes place upon melting in the twin screw extruder. Upon processing in the single screw extruder re-agglomeration may occur, while dispersion in the metering zone depends on screw speed.The authors acknowledge the financial support to Project Matepro – Optimizing Materials and Processes, with reference NORTE-07-0124-FEDER-000037 by the Programa Operacional Regional do Norte (ON.2) and Portuguese Foundation for the Science and Technology (FCT) for PEst-C/CTM/LA0025/2013.