简 介: |
The morphology and filler dispersion in polymer-clay nanocomposites are usually characterized by offline techniques,like, transmission electron microscopy (TEM), atomic force microscopy (AFM) [1], small angle X-ray scattering (SAXS), nuclear magnetic resonance (NMR) [2] and Fourier transform infrared spectroscopy (FTIR) [3]. The offline experimental technique are not only time consuming, labor intensive, expensive, requiring a high expertise but also crucial in determining the influence of processing parameters on the resulting microstructure. Replacing the offline measurements or minimizing them with an online measurement method, which would quite cost effective and easy in handling. The online measured electrical conductance (OMEC) method, reported in this article is based on conductivity and has been successfully used for the qualitative and quantitative characterization of the kinetics of carbon black (CB) and carbon nano tubes (CNT) in rubber compounds as well as in rubber blends [4]. The conductivity in the polymer-clay nanocomposites is ionic in nature [5]. It is presumed that mixing organoclay imparts the ammonium cation due to intercalation and exfoliation in the rubber matrix. Thus, the received electrical signal can be used for the investigation of the change of the clay dispersion in the host polymer during the mixing process. Bur et al. [5,6] used dielectrical measurements and detected the online electrical signals during melt mixing of polyamide-clay nanocomposites in twin screw extrusion. This method gives the morphology of the nanocomposites at only one position, i.e. the position of sensor,but fails to display the complete spectrum of clay dispersion in the polymer matrix |