Analysis of tensile and flexural modulus in hemp strands/polypropylene composites

This research focuses on the behavior of the tensile and flexural modulus of polypropylene/hemps strands composites. The intrinsic tensile modulus of the hemp strands was computed using Hirsch model and experimental data of the tensile modulus of the polypropylene composites at the 20-50 wt.% hemp strands content. The modified rule of mixtures was used to evaluate the efficiency factor. Square packing distribution was assumed and the length factor was fixed by Cox-Krenchel's model. The mean value of the orientation efficiency factor was found to be 0.55. Tensile and flexural modulus were compared concluding that its value was independent of the manner the composite was loaded. Finally the Tsai-Pagano model was applied to predict the behavior of the composite's tensile modulus.