Poly (vinylidene fluoride) (PVDF)/graphite composites were prepared by solution mixing technique then subjected to hot compression molding. Tensile mechanical properties of prepared composites were studied at different temperatures between 30 and 90 oC. The results indicated that, the elastic modulus, tensile strength, and ultimate elongation achieved a significant improvement with addition of graphite showing maxima around 3.9vol% graphite, followed by a decrease with further increases of the graphite content. This behaviour suggested the formation of a compact structure, and above a content of 3.9vol% graphite, this compact structure became more loose. These results were confirmed by both SEM and DSC measurements. DSC measurement indicated that graphite content has significant influence on the degree of crystallinity for PVDF composites. Also, study of the melting behaviour suggested the presence of only α-crystalline phase in neat PVDF and PVDF/G composites. The observed values of the elastic modulus of the composites are in close agreement with those calculated by Halpin-Tsai's model, taking into account the variation of the aspect ratio (αg) of the graphite structure with the volume fraction of the graphite in the matrix. The elastic modulus, tensile strength and yield stress were found to decrease with increasing the working temperature, while the ultimate elongation exhibit opposite trend.
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