A study of the effect of surface treatments on the tensile strength of flax fibres: Part I. Application of Gaussian statistics

Natural fibres are considered to be a potential alternative to glass fibres for use in composites applications. However, although natural fibres have many advantages their compatibility with most thermoplastics is rather poor. Surface treatments, although having a negative impact on economics, may be applied to overcome the problem of interfacial adhesion. Unfortunately, natural fibres being very different materials from man-made fibres, are very prone to degradation and/or structure alteration during the application of surface treatments. This study focuses on the effect of two surface treatments (acetylation and stearation) upon the tensile strength of flax fibres. The results are discussed in terms of Gaussian statistics and it was found that the treatments did not significantly change the flax fibre tensile strength. In addition SEM examination of the fractured surfaces revealed that acetylated fibres exhibit a different mode of failure from the other fibres, suggesting that the treatment altered the bulk properties along with the surface properties.