On-line morphological and rheological studies of polypropylene-polystyrene-nanoclay nanocomposites
S. Cho, K.H. Ahn, S.J. Lee, A.V. Machado, J.A. Covas and J.M. Maia
University of Minho, PT
nanocomposites, extrusion, on-line rheology, optimisation
In order to overcome the problems associated with finding an appropriate compatibilizer in polymer blends, functionalized modifier or a copolymer has usually been added to the mixture as compatibilizers. The possibility of compatibilizing incompatible polymer blends by adding relatively cheap organoclays is very appealing from the standpoint of practical applications. In this study, morphological and rheological evolution of polypropylene(PP)/polystyrene(PS) blend clay nanocomposites were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and on-line rheological techniques. Organoclays located at the interface resulted in the dramatic reduction of particle size and narrower particle size distribution of the dispersed phase, morphological stabilization, and the increase of rheological properties. The kinetics for the compatibilization of PP/PS blend nanocomposites is also discussed based on the TEM results of the hybrids depending on melt-mixing time and in terms of the evolution of the morphology and of the rheological properties of the blends along the length of the extruder. Particular attention will be paid to the influence of both processing conditions, e.g., output, temperature and screw speed and material characteristics, e.g., viscosity ratio, clay content and relative PP/PS ratios.
Back to Program
Nanotech 2006 Conference Program Abstract