Synthesis of partially exfoliated EPDM/LDH nanocomposites by solution intercalation: Structural characterization and properties

Partially exfoliated ethylene propylene diene terpolymer (EPDM)/Mg-Al layered double hydroxide (LDH) nanocomposites have been synthesized by solution intercalation using organically modified LDH (DS-LDH) as nanofiller obtained by reconstruction method using sodium dodecyl sulfate and LDH. The nanocomposite structure has been elucidated by the X-ray diffraction (XRD), transmission electron rnicroscopy (TEM), atomic force microscopy (AFM), Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The molecular level dispersion of LDH nanolayers has been verified by the disappearance of basal XRD peak of DS-LDH in the composites and studied by TEM and AFM. The mechanical properties showed significant improvement of EPDM/DS-LDH nanocomposites (2-8 wt.%) with respect to neat EPDM. Thermogravimetric analysis (TGA) shows thermal stability of nanocomposites containing 3 wt.% DS-LDH improved by approximate to 40 degrees C when 10% weight loss was selected as point of comparison. The first step in the decomposition process induces the charring and can account for better fire safety of the nanocomposites. Optical studies showed better clarity at lower DS-LDH loading in EPDM/LDH nanocomposites. (c) 2007 Elsevier Ltd. All rights reserved.