Tensile Behavior of Sisal/Hemp Reinforced High Density Polyethylene Hybrid Composite☆

The study investigates the effect of reinforcing sisal and hemp fibers, either alone or simultaneous, into polymer matrix, containing 50-50 mixture of fresh and recycled HDPE, on the tensile behavior. Prior to manufacturing of composite, the fibers were chemically treated with NaOH and Maleic Anhydride (coupling agent). The tensile strength of the sisal-hemp fibers/HDPE hybrid composite is observed to be superior to single fiber (hemp/sisal) reinforced HDPE composites. The sisal fiber appears to be the primary reinforcing agent and dominates over hemp fiber in controlling the tensile strength of the hybrid composites. The tensile strength of the hybrid composite increases with increasing sisal content from 5% to 20% but decreases with increasing the content of hemp fiber 5% to 20%. The operative failure modes in the composites are observed to be fiber pull out and fiber breakage.