Structural characterization and related properties of EVA/ZnAl-LDH nanocomposites prepared by melt and solution intercalation

The crystal morphological structures, thermal and mechanical properties of ethylene-vinyl acetate copolymer/layered double hydroxide (EVA/LDH) nanocomposties prepared by melt and solution intercalation methods have been studied by X-ray diffraction (XRD), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and mechanical measurements. The XRD data show that the exfoliated EVA/LDH nanocomposites can be obtained by controlling the LDH loading of about 10% for the melt intercalation and 5% for the solution intercalation. The TEM images verify that the exfoliated nanocomposites are of the nanoscale dispersion of LDH layers in the EVA matrix. The thickness and size of single LDH platelet are 1 nm and 100-150 nm. The TGA data give evidence that the thermal degradation temperatures of the EVA/LDH nanocomposite samples are 13-35 deg. C higher than that of pure EVA resin when 50% weight loss was selected as a point of comparison. The data from the mechanical test show that the tensile strength values of the EVA/ZnAl-LDH nanocomposite samples are 2.5-4.8 MPa higher than that of pure EVA resin, and their tensile modulus increases continuously with the increase of LDH loadings, while the elongation at break is almost the same as that of the pure EVA resin