Preparation and rheological characteristics of ethylene-vinyl acetate copolymer/organoclay nanocomposites

摘要

Ethylene-vinyl acetate copolymer ( EVA) with 40 wt.% vinyl acetate content ( EVA40)/organoclay nanocomposites were prepared using a melt intercalation method with several different clay concentrations ( 2.5, 5.0, 7.5, and 10.0 wt.%). X-ray diffraction confirmed the formation of exfoliated nanocomposite in all cases with disappearance of the characteristic peak corresponding to the d-spacing of the pristine organoclay. Transmission electron microscopy studies also showed an exfoliated morphology of the nanocomposites. Morphology and thermal properties of the nanocomposites were further examined by means of scanning electron microscopy ( SEM) and thermo gravimetric analysis ( TGA), respectively. Rheological properties of the EVA40/organoclay nanocomposites were investigated using a rotational rheometer with parallel-plate geometry in both steady shear and dynamic modes, demonstrating remarkable differences with the clay contents in comparison to that of pure EVA40 copolymer.