Ethylene vinyl acetate/cellulose composites: functional modification, morphology and phase interactions.

Incorporation of cellulosic fibres into polymers matrices offers the possibility to design new composite materials with reduced environmental impact, due to the biodegradability, renewability and low cost of natural fillers. Indeed, good dispersion of fibres in the polymer matrix and good adhesion is an important prerequisite for obtaining good mechanical properties of the resulting composites. To increase the compatibility of the components, improving the interfacial adhesion and fibre dispersion within the polymer matrix, either surface modification of fibre and/or matrix are necessary [1-2]. The present communication is aimed at analysing the effect of compatibilization processes of ethylene vinyl acetate (EVA) composites with natural fibres, such as cellulose and hemp, on the morphological, thermal and mechanical properties. The composites were obtained by melt mixing EVA copolymers of different types with fibre contents in the range of 20-50 wt% using a Brabender internal mixer. Commercial samples of EVA (28 wt.% vinyl acetate), maleic anhydride grafted EVA (EVA-MA) and glycidyl methacrylate modified EVA (EVA-GMA) were used. The effect of polymer functionalization, fibre treatment and content, on the composite properties was then examined by SEM, FT-IR, DMTA, DSC, TGA and tensile mechanical tests.