Effect of moisture in flax fiber on viscoelastic properties of the manufactured flax fiber reinforced polymer by fractional-order viscoelastic model

Flax Fiber Reinforced Polymer (FFRP) composites, known for their eco-friendliness and mechanical strength, find extensive application in construction. This study investigates the influence of moisture content in flax fiber fabrics on FFRP's viscoelastic properties. Isothermal frequency sweep tests were conducted to assess dynamic mechanical properties under varying moisture levels. The Huet-Sayegh viscoelastic model, with fractional order integration, was employed for analysis. Results indicate optimal viscoelastic properties when fabric humidity matches manufacturing conditions. However, the correlation between the loss factor and the humidity is not straightforward. In summary, FFRP's capacity to store and dissipate energy diminishes with the increased moisture content, but the reduction does not follow a specific pattern with humidity levels.