PLA, MA and BPO were dried at 60 C in vacuum for 10 h. The
dried PLA, MA and BPO were firstly well mixed by a high speed
mixer. And then BPO as initiator with PLA and MA were blended
in a co-rotating twin-screw extruder (20 mm, L/D = 40; Nanjing
Jieya, China) at operating temperatures from 155 to 170 C