Natural fibres are emerging as low cost, lightweight and environmentally superior alternative in composites. Different fibres will exhibit different properties that are fundamentally important to the resultant composites. In this paper an attempt is made to give an overview of different fibres most commonly used in composites, their extraction methods, characterization and treatments to improve fibre performance, composite manufacture and mechanical properties.
Bio composites are composite materials comprising at least one major component derived from a biological origin. The bio materials that are long textile fibres used as reinforcements are Flax, Jute, Hemp and Ramie and short fibres like wood fibres and recycled fibres. The polymer matrix used is biopolymers, but most of them are in the developmental stage. Vast majority of the composites are made from the combination of bio-fibres and petrochemical based matrices.
The use of natural fibres in composites has experienced a rapid growth with still some major technical and economical challenges ahead. Majority of the natural fibre composites contain too much short fibres and they are suitable for nonwoven processing and finally end up in manufacturing of composites with moderate mechanical properties. Fibre orientation plays a major role in achieving maximum fibre fraction ratio and fibre utilization efficiency in the resulting composites. A high moisture absorption property of natural fibres is a disadvantage in composite applications. Bio-composites are typically made from a combination of natural fibres and petrol based resins.
Originally Published in the Textile Review, January, 2012.
About the Author:
K. P. Kathirvel is an Assistant Professor, Department of Textile Technology, KSR College of Technology, Tiruchengode
Dr. T. Ramachandran is the Principal, Karpagam Institute of Technology, Coimbatore.