Masterbatch-based multi-walled carbon nanotube filled polypropylene nanocomposites: Assessment of rheological and mechanical properties

• Published in: Composites science and technology Vol. 69; no. 11; pp. 1756 - 1763
• Main Authors: Prashantha, K., Soulestin, J., Lacrampe, M.F., Krawczak, P., Dupin, G., Claes, M.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Kidlington Elsevier Ltd 01.09.2009; Elsevier
• Subjects: A. Nanocomposites; Applied sciences; B. Mechanical properties; Chemical and Process Engineering; Chemical Sciences; Composites; D. Rheology; D. Scanning electron microscopy (SEM); D. Transmission electron microscopy (TEM); Engineering Sciences; Exact sciences and technology; Forms of application and semi-finished materials; Materials; Mechanics; Mechanics of materials; Polymer industry, paints, wood; Polymers; Technology of polymers; B. Mechanical properties; D. Transmission electron microscopy (TEM); A. Nanocomposites; D. Rheology; D. Scanning electron microscopy (SEM); Strengthening; Double screw extruder; Propylene polymer; Carbon nanotubes; Mechanical properties; Dispersion reinforced material; Tensile property; Experimental study; Masterbatch; Composite material; Shear viscosity; Multiwalled nanotube; Impact strength; Morphology; Concentration effect; Extrusion; Olefin polymer; Nanocomposite; Rheological properties
• ISSN: 0266-3538; 1879-1050
• DOI: 10.1016/j.compscitech.2008.10.005

Polypropylene (PP)/multi-wall carbon nanotubes (MWNTs) nanocomposites were prepared by diluting a PP/MWNT masterbatch by melt compounding with a twin screw extruder and prepared nanocomposites were characterized for their rheological, mechanical and morphological properties in terms of MWNT loading. The rheological results showed that the materials experience a fluid–solid transition at the composition of 2 wt.%, beyond which a continuous MWNT network forms throughout the matrix and in turn promotes the reinforcement. The tensile modulus and yield stress of the nanocomposites are substantially increased relative to the neat polypropylene. Nanotube reinforcement thus enhanced the yield stress, while reducing the ductility. The same behavior is observed in flexural tests. Charpy impact resistance of the notched samples increases slightly by the addition of MWNT, while impact resistance for the un-notched samples decreases with the addition of MWNTs. Finally, optimum in mechanical properties was observed at 2 wt.% MWNTs, which is near the rheological percolation threshold. From transmission electron microscopic (TEM) and scanning electron microscopy (SEM) images, it was observed that nanotubes are distributed reasonably uniformly indicating a good dispersion of nanotubes in the PP matrix. These results reveal that, preparation of nanocomposites from masterbatch dilution is an excellent method to obtain well-dispersed CNTs, while limiting the handling difficulties in plastics processing industrial workshops.