The applications of biopolymers that are requested in the society for sustainability and environmental safety have many limitations. That is can be attributed to the limited mechanical and thermal properties of biopolymers. The aim of this study is to diminish the limitations of the biopolymers properties. Polylactic acid (PLA) as one of the famous biopolymers was selected to investigate the effect of incorporating of hybrid fillers, natural halloysites nanotubes HNTs and Zirconium dioxide (ZrO2) nanoparticles. In the first stage, HNTs was added to PLA matrix in different loading (0, 2, 4, 6 and 8 wt%). In the next stage ZrO2 was incorporated to PLA/HNTs in two loadings (1 and 3 wt%). The mechanical properties (tensile strength, elongation at break and Young's modulus) were investigated for both of PLA/HNTs and PLA/HNTs-ZrO2 bionanocomposites. PLA films incorporated with 4 wt% loading of HNTs resulted in optimum mechanical properties due to the homogenous distribution of halloysite nanoclay, which increased the tensile strength and elongation at break by 70% and 27% respectively. Unfortunately, the addition of ZrO2 reduced the mechanical properties of PLA/HNTs-ZrO2.
