Natural fibre composites biodegradable fibres

Most of the previous research on natural fibre composites has focused on reinforcements such as flax, hemp, sisal and jute, and thermoplastic and thermoset matrices. Some of these composites have been produced using matrices made of derivatives from cellulose, starch and lactic acid to develop fully biodegradable composites or biocomposites [52]. The emerging diversity of applications of natural fibre composites has seen the production of sandwich structures based on natural fibre composite skins (see Fig. 23.10). 

Kapanen A., Venelampi O., Vikman M., Itavaara M. Testing the ecotoxicity of biodegradable plastics, KTBL-Schrift 414 biodegradable materials and natural fibre composites. Darmstadt Kuratorium filr Technik und Bauwesen in der Landwirtschaft e.V (KTBL), 2002,107. 

Proceedings of the International Symposium on Biodegradable Materials and Natural Fibre Composites in Agriculture and Horticulture, Hanover, Germany, 2002. 

Table 8.6 Mechanical properties of natural fibre-synthetic biodegradable polymer composites... 

Plackett D V and Andersen T L (2002), Biocomposites from natural fibres and biodegradable polymers processing, properties and future prospects , Ldholt H et al.. Sustainable Natural and Polymeric Composites - Science and Technology,... 

In recent years starch, the polysaccharide of cereals, legumes and tubers, has acquired relevance as a biodegradable polymer and is becoming increasingly important as an industrial material (Fritz Aichholzer, 1995). Starch is a thermoplastic polymer and it can therefore be extruded or injection moulded (Balta Calleja et al, 1999). It can also be processed by application of pressure and heat. Starch has been used successfully as a matrix in composites of natural fibres (flax, jute, etc.). The use of starch in these composites could be of value in applications such as automobile interiors. An advantage of this biopolymer is that its preparation as well as its destruction do not act negatively upon the environment. A further advantage of starch is its low price as compared with conventional synthetic thermoplastics (PE, PP). 

Properties such as density, electrical resistance, ultimate tensile strength and initial modulus are related to the internal structure and chemical composition of the fibres. Properties may also vary according to variations in diameter along with the length of individual filaments, size and maturity, as well as the processing methods used for the extraction of fibres. These fibres are biodegradable and non-abrasive. However, incompatibility of the fibres and poor resistance to moisture often reduces the potential of natural fibres and these drawbacks have become a critical issue in their development." ... 

In the case of natural fibre reinforced polymer composites,in 1996 this material was used for making aeroplane seats and fuel tanks. The last decade has been used widely because of biodegradability and high specific properties. Currently, nanobiofibre composites are also provided for material revolution in technical application which is taking place in the automobile and packaging industrial. 

Wollerdorfer M, Bader H (1998) Influence of natural fibres on the mechanical properties of biodegradable polymers, bid Crops Prod 8 105-112 Wong S, Shanks RA, Hodzic A (2007) Effect of additives on the interfacial strength of poly(l-lactic acid) and poly(3-hydroxy butyric acid)-flax fibre composites. Compos Sci Technol 67 2478-2484... 

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