About optimal architecture of plant fibre textile composite for mechanical and sorption properties

International audienceThe aim of this work is to establish simple rules to optimise the architecture of plant woven fabric reinforcement for structural composite applications (sorption and mechanic aspects). For that, the influence of architectural parameters of reinforcement such as the frame, the yarn diameter, the pick count, and the filling rate, was studied from six different flax fabrics (2 quasi-unidirectionals and 4 balanced twills) and two processing techniques (autoclave and hot platen press). On the one hand, in order to normalise the effects of fibre fraction, porosity fraction and architectural parameters, a model was developped to analyse the mechanical properties at the level of the yarn. On the other hand, after demonstrating that the classical model of Fick does not properly fit the sorption of plant fibre textile composite, a two-phase Fick’s diffusion model was applied. It results that the best fabric architecture concerning mechanical and sorption properties is a compromise mixing high filling rate of woven fabrics, small shrinkage of yarns, and small yarn diameter