Mechanical properties comparison of autochthonous natural fibers reinforced polyester composites: flax and hemp

• Main Author: Rocha, João
• Publication Date: 2016
• Other Authors: Ribeiro, J.E., Queijo, Luis
• Language: eng
• Source: Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
• Download full: http://hdl.handle.net/10198/16381
• topic: Flax; Hemp

Nowadays, the climate changing caused by the increasing of pollution and the need of reduce the carbon footprint brings the growing use of autochthonous materials. On the other hand, there are new European Community directives that require the increased use of recyclable materials and the natural fibres are excellent candidates for this role. However, only in last few years this subject has been studied for technical applications [1]. This work intends to add a small contribution to better characterize composites with some of these natural fibres. For that reason, is used the Taguchi method [2] to characterize composites of natural fibers, namely the hemp and flax fibres which will be used individually and mixed each other. The factors that will be controlled are, beyond the type of fibres, the interfacial strength, the humidity in the fibres and the fibre weight fraction. To implement the experimental tests will be used the method of design of experiments developed by Taguchi. In this case, is used the L9 orthogonal array because is more suitable for the number of factors and levels analysed. So, for the interface strength improvement is used the alkali–silane treatment and are applied three different concentrations that are 0%, 2% and 5%. The humidity in the fibres is a very difficult parameter to control and for this reason will be used different ranges which will be obtained by controlling the drying time. Finally, will be used different values of fibre weight fraction to determine its influence in the tensile strength of the composite. Considering the number of factors to be controlled and the number of levels, the data that is analyzed is the tensile properties. The influence of each factor in the composite performance will determined using the analysis of variance (ANOVA) as well as the optimal factors and levels combination to obtain the highest values of tensile strength.