Mechanical Properties and Morphology of Composites Based on the EVA Copolymer Filled with Expanded Graphite

Polymeric composites were prepared using ethylene-vinylacetate (EVA) matrix and expanded graphite (EG). Mechanical properties were investigated and it was found that Young's modulus and the yield stress of EVA-EG composites significantly increased with graphite content. However, for higher EG content the composites became brittle. The dependence of stress at the break of composites reached maximum at 30 vol.% of the filler. The morphology of both EG filler and composites were investigated using transmission electron microscopy and Raman spectroscopy. All these structural characterizations indicated partial exfoliation of EG within EVA matrix, which leads to the increase of the reinforcement effect.