Analysis of Composite Material on Natural Fibre and Natural Resin

Over the last decade, composites of Natural resin reinforced with natural fibres have received increasing attention, both from the academic world and from several industries. There is a wide range of natural fibres which can be applied as reinforcements or fillers thanks to their properties and availability; i.e. flax, hemp, jute, kenaf and sisal. Natural composite materials are mainly attractive for the following reasons: specific properties, price, health advantages and recyclability. Despite such good premises, these fibres have also some negative characteristics: they are highly hydrophilic and their properties may vary in time. The natural fibres have a complex structure of elementary fibres, consisting of cellulose, hemicellulose, pectin, lignin and others and thus they should not be considered as monofilament fibres. Mechanical, physical and even chemical properties of these fibres are strongly harvest dependent, influenced by climate, location, soil characteristics, and weather circumstances. They are affected also by fibre processing (i.e. retting, scutching, bleaching, spinning) and by their incorporation into composites: handling, impregnation and consolidation may introduce supplementary changes. Obviously, such variability complicates the prediction and the evaluation of the composite properties. Another known problem in natural fibre reinforced composites is the poor interface quality between the fibres and the polymer matrix. Chemical pre-treatments are often applied in order to enhance the adhesion between these components.