Prior to blending, the PLA and two types of ENR were separately dried at 80 °C and 40 °C for at least 8 h in a vacuum oven. ENR20/PLA and ENR50/PLA blends were both prepared at various ENR contents (1%, 3%, 5%, 10% and 20%, by weight based on PLA, respectively) in a Haake internal melt mixer (Rheocord 90, Germany) at a rotor speed of 60 rpm, 170 °C for 10 min. The well mixed blends were cut into small granules. Pure PLA was treated with the same procedure for comparison.