ABSTRACT
Halloysite is relatively new nanofiller in the field of polymer nanocomposites. In order to investigate the potential reinforcement of this tubular aluminosilicate in polymeric materials, it is of interest to compare the mechanical performance of halloysite nanocomposites with that of more conventional ones. In his PhD study, Van Es (2001) modelled and compared the mechanical reinforcement of unidirectionally aligned fibres and platelets (Figure 20.1), according to Halpin-Tsai’s and MoriTanaka’s equations. This graph shows that both models are equivalent for a fitted value of the shape factor ζ (ζ = 2/3 l/t for platelets and ζ = (0.5 l/t)1.8 for rods). At a given aspect ratio, the reinforcing action of fibres (triangles) is higher than that of platelets (dots). Moreover, the upper limit (i.e., rule of mixture) is already reached at an aspect ratio of 100 for fibers and 1,000 for sheets.
