Research on mechanical properties and durability of flax/glass fiber bio-hybrid FRP composites laminates

Abstract

In recent years, natural fiber as a green and renewable resources have attracted much attention to be used as reinforcement in composites. The aim of this work is to assess mechanical properties and durability in harsh environments of epoxy-based flax and glass bio-hybrid fiber reinforced plastics (bio-HFRP) composites. With the same fiber mixing ratio, the flexural and dynamic mechanical properties of the bio-HFRP composites were studied by changing the stacking order. The pure flax FRP and bio-HFRP composites were exposed to hygrothermal at 20 °C, 40 °C, and 60 °C for 28 days, respectively. The water absorption and diffusion capacity, the bending and shear properties were analyzed. Compared with the pure flax FRP, the flexural strength of G2F2s group sample was increased by 2.2 times. When exposed to the hygrothermal environment, flexural strength loss rate of the G2F2s group sample is only reduced by 4.35%, 9.00% and 11.51%, and its flexural modulus decreases 15.48%, 15.90% and 23.89%. It shown that the addition of glass fiber effectively improves the water absorption of flax fiber composites. Hybridization of flax fibers with glass fibers was a practical approach to enhance FRP laminates in hygrothermal environmental conditions after synthesizing the stacking sequence, mechanical properties and aging resistance.