Dispersion characterization in layered double hydroxide/Nylon 66 nanocomposites using FIB imaging

Layered double hydroxides (LDHs), a newly emerging 2D host material, consist of cationic brucite-like layers and exchangeable interlayer anions. In this work, the morphology and dispersion of LDH particles in LDH/ Nylon 66 (salt) nanocomposites has been investigated using focused ion beam (FIB) techniques, transmission electron microscopy (TEM) and X-ray diffraction (XRD). The FIB images show that LDHs are present in the polymer phase dispersed to different degrees, with partial intercalation, exfoliation, and aggregation all being observed. The most even dispersion was achieved in nanocomposites with the lowest loading (0.5 wt % LDH). Residual tactoids and agglomerates were most common in the samples made with the highest concentration of LDHs studied here (5 wt %). The dispersion observed using FIB was consistent with TEM and XRD analysis, yet this technique had significant benefits in terms of time and simplicity over these "conventional" technologies. (C) 2008 Wiley Periodicals, Inc.