Evaluation of a new processing method for improved nanocomposite dispersions

Herein, a new process referred to as melt-mastication (MM) is used for the first time and evaluated for dispersing nanoparticles in polymers. Compared to a conventional melt processing (CMP) technique, MM produces higher mixing torque and therefore shear in the melt during processing, resulting in the fragmentation of micrometer-scale agglomerates of exfoliated graphene nanoplatelets (xGnP) in polypropylene. The efficacy of MM compared to CMP is evaluated using quantitative stereological techniques. Stereology reveals a correlation between the steady state process torque and the spatial size distribution of agglomerates. Finally, a mechanism for agglomerate fragmentation is proposed and discussed with respect to the results.