Development of new composite products based on flax fibres

Abstract

Plant fibres are materials that can increase energy savings, and they are being analysed for their reduced environmental impact. In this paper, three types of multi-layered panels were developed as environmentally friendly flax fibre-based products for building industry applications. The structural build-up of the panels is such that one layer of waste flax fibre was used as the core material in order to reduce the weight of the structure between two rigid perlite-based layers. The perlite was used in three varied grain sizes, resulting in three types of panels (S1, S2, S3 ). The mechanical, thermal and acoustic properties were recorded for all specimens. The influence of the perlite particles’ size, perforation diameter and perforation percentage of the multi-layered panels on the acoustic absorption properties was analysed and discussed. Summarising the results, the multi-layered composite panel S3 presented the best performance in regard to compressive strength and thermal conductivity, with S2 presenting the best bending strength. From the acoustic point of view, for the unperforated panels, the highest values of the sound absorption coefficient were obtained at 500 Hz for S1, α = 0.95, 315 Hz for S2, α = 0.89 and 400 Hz for S3, α = 0.84. The obtained values of the sound absorption coefficients were increased through the varied perforation diameters and percentages of the panels’ front face.