Secondary structure and elevated temperature crystallite morphology of nylon-6/layered silicate nanocomposites

Mesoscale (secondary) structure arising from association of layered silicat es is quantified and its impact, along with constituent interactions, on el evated temperature crystallite morphology in nylon-6/montmorillonite nanoco mposites is examined. Simultaneous small- and wide-angle X-ray scattering a nd diffraction methods are developed to provide detailed information on the secondary structure of the layered silicate and the structure of the cryst alline polymer in the presence of the layered silicate. Ultra-long range or der (20-60 nm) of the inorganic layers is observed at low-volume fractions (0.8 vol%). Elevated temperature (205 degreesC) crystallite morphology of t he nylon-6 matrix depends on the secondary structure and interfacial intera ctions. Smaller, more disordered lamellae are observed in the in situ polym erized nanocomposites whereas larger, more ordered lamellae are observed in melt-processed nanocomposites. (C) 2000 Elsevier Science Ltd. AU rights re served.