Fabrication and mechanical properties of a recycled hemp fiber composite

Natural fiber-reinforced composites are fast becoming the choice material in various industries because of their mechanical properties and long term sustainability; however, this study is the only work to date on the feasibility of using recycled hemp fibers. Composites fabricated from recycled hemp sacks were tested to determine their tensile strength properties. Compared to virgin-hemp yarn composites, recycled hemp yarn composites are weak, with tensile strength of 39 MPa. However, addition of hemp resulted in a modulus of elasticity of 765 MPa, a 100% improvement in the modulus of elasticity compared to the epoxy matrix (386 MPa). This study found that hemp surface treatment weakened the fiber, caused fiber loss, and reduced the fiber weight fraction, so no further processing is recommended when using long-fiber recycled hemp. According to the study, the volume fraction of the fiber is 15.6%, and only marginally increases tensile strength. However, it is cheap, and should not be precluded from use in composites, as there are many other synthetic-hemp fiber hybrid composites to be explored