Phoenix dactylifera l. pinnae (the green leaves of dates palm) were used as natural reinforcing (strengthening) fibers to improve the mechanical properties of polyester as a matrix material, the fibers of the green leaves of dates palm were used in two lengths, 10 and 20mm with five rates of 0, 2.5, 5, 10, and 20% , where the reinforcing with the leaves fibers increases the hardness strength from 76.5 to be about 86.55 , the Impact value raised from about 0.313 to 0.461 , in addition to that the flexural strength from 2.66 to be about 55 , and the thermal conductivity increases from 2.54

Phoenix Dactylifera --- Biocomposite --- mechanical properties --- Natural fibers.

This work take in consideration the application of Taguchi optimizationmethodology in optimizing the parameters for processing (composition,compounding pressure) and their effects on the output physical (Density and trueporosity) properties and mechanical(fracture strength and microhardness)properties for the Nano HA,Al2O3 fillers reinforced HDPE hybrid compositematerial for orthodontic application. An orthogonal array of the Taguchiapproach was used to analyses the effect of the processing parameters on thephysical and mechanical properties. On the other hand, the surface roughnessand particle size distribution were also calculated to study their effect on theoutput properties. The result shows that the Taguchi approach can determine thebest combination of processing parameters that can provide the optimal physicaland mechanical conditions, which are the optimum values (the optimumcomposition was15HA/ 5Al2O3/80HDPE, and optimum compounding pressurewas102 MPa.

Taguchi method --- Physical Properties --- hybrid biocomposite --- Mechanical properties