No abstract

Non-dry flax fibre and polyester resin that has low sensitivity to moisture were used in the production of composites and the effects on flexural and moisture sorption properties of composites under wet-dry cycling were determined. Results showed that composites made of non-dry fibre have lower moisture sorption and degree of swelling and shrinking compared to composites made of dried fibre. Mean strength and modulus of composites made of non-dry fibre are 4-12% and 13-14% respectively, higher than composites made of dried fibre in longitudinal direction. Mean strength and modulus of composites made of non-dry fibre are 18-22% and 11-21% respectively, higher than composites made of dried fibre in transverse direction after the wet-dry cycling. The results suggest that composites made of non-dry fibre could be used for enhancing moisture durability of composites and lessen the time, cost and embodied energy to produce the composites, by omitting the step of drying the fibres.

This study was performed to evaluate the effect of water immersion ageing on flexural and water sorption properties of composites made of non-dry flax fibres (conditioned at 50% and 80% relative humidities) and resins that have low sensitivity to water. The experimental results showed that throughout the ageing study, composites made of non-dry fibre have lower moisture sorption and better flexural properties compared to composites made of dried fibre.