Preparation and characterization of EVA/MMT nanocomposites

Nanocomposites composed of poly(ethylene-co-vinyl acetate) (EVA) and montmorillonite (MMT) were prepared by melt intercalation. Their structure and properties were studied by FT-IR, XRD, TGA, the Molau test, and tensile and tear strength measurements. The results showed that those silicate layers of MMT treated with the swelling agent hexadecyl trimethylammonium. bromide (CTAB) were dispersed in the EVA matrix on a nanometer scale and an intercalated EVA/MMT nanocomposite was obtained. The interfacial interaction, tensile strength and tear strength of those EVA/MMT samples treated with CTAB (denoted by MMT-CTAB) nanocomposites were noticeably improved. Whether treated or not, the composites underwent two thermal degradation steps. In the first step, the thermal stability of EVA/CTAB-MMT nanocomposites was lower than that of EVA/ MMT ones because of the degradation of the swelling agent, whereas in the second step EVA/CTAB-MMT nanocomposites exhibited higher thermal stability.