Quantitative characterization of exfoliation in polyamide-6/layered silicate nanocomposites

A quantitative characterization of the structure of polymer/layered silicate nanocomposites is proposed. The methodology, based on TEM image analysis was applied, to the quantitative characterization of PA-6/montmorillonite nanocomposites produced by melt-compounding. The influence of the organic modification of the montmorillonite (MMT) on the quality of the dispersion of the clay particles was evaluated quantitatively. The efficiency of a specially designed extruder system was evaluated and compared to a reference nanocomposite produced by in-situ polymerization. Surface density, specific area, extent of exfoliation, particle dimensions, and aspect ratio of the dispersed particles were estimated and correlated with mechanical properties.