Rheology of Carbon Nanofiber-Reinforced Polypropylene

The rheol. properties of two different nanocomposite systems consisting in the dispersion of carbon nanofibers (CNFs) in polypropylene are investigated. The nanoreinforced systems were identically prepd. with two CNFs that differ only in the length of the fibers being otherwise identical to analyze the effect of fiber aspect ratio. Linear dynamic viscoelasticity and the steady-state rheol. of the two different nanocomposites are presented. The system reinforced with CNFs with larger aspect ratio shows several rheol. features that resemble peculiarities of rodlike polymers in the nematic liq. cryst. phase