It was investigated how the aspect ratios of kenaf fibers measured before and after passing
through extrusion process influence the mechanical properties and the improvement of predicted values
obtained by the Halpin–Tsai equation. It was found that considering of the aspect ratio of reinforcement
obtained after the extrusion process, the difference between theoretical and experimental values of the
tensile modulus was not significant, indicating that the aspect ratio determined after extrusion did not
influence the predicted values. Therefore it was pointed out that the initial values of aspect ratio determined
before extrusion can be used directly.