X–ray diffraction is used to probe the crystallinity of neat PLA, PBAT and their blends. Thin film samples are analyzed using a wide-angle X-ray diffraction apparatus (shimadu XRD-6000) by Cu Ka (k ¼ 0.154nm) under a voltage of 35 KV and a current of 25mA radiation. Diffraction intensities are counted at 0.02 -steps and the scanning speed is 5/min. The spectra are recorded in an angular range 5 < 2 y < 40 at room temperature