▎ 摘　　要

Phosphorylated graphene oxide (PGO) was prepared by using phosphoric acid as functional reagent, and PGO was grafted with poly(L-lactide) (PGO-PLLA) by ring-opening polymerization of L-lactide as monomer under nano-ZnO catalyst. The results of the orthogonal analysis showed the optimum reaction conditions to be as follows: the reaction temperature of 170 degrees C, reaction time of 14 hours, the mass ratio of PGO of 10 wt%, and the mass of nano-ZnO of 1 wt%. PGO-PLLA was characterized by fourier transform infrared spectroscopy, gel permeation chromatography, and X-ray photoelectron spectroscopy, which demonstrated that the PLLA molecular chains were successfully grafted onto the surface of PGO. Poly (lactic acid)/PGO-PLLA nanocomposites (PLA/PGO-PLLA) were prepared by melt intercalation. Mechanical test and fracture scanning electron microscopy showed that PGO-PLLA (0.3 wt%) improved impact strength of PLA by 52.19%, which resulted in ductile fractures surface of PLA/PGO-PLLA. Microcalorimetry and thermal degradation kinetics proved that PGO-PLLA improved the thermal stability of PLA. Polarized optical microscopy and differential scanning calorimetry confirmed that PGO-PLLA increased crystallization rate and spherulite kernel density of PLA, and crystallinity of PLA/PGO-PLLA reached to 22.05%. Rheological behavior proved that PGO-PLLA increased the self-lubricity of PLA. Enzymatic degradation results illustrated that PGO-PLLA had some inhibition for the biodegradability of PLA based nanocomposites.