Synthesis of polylactide‐graft‐glycidyl methacrylate graft copolymer and its application as a coupling agent in polylactide/bamboo flour biocomposites

In this study, a novel graft copolymer, polylactide‐ graft ‐glycidyl methacrylate (PLA–GMA), was synthesized by the grafting of glycidyl methacrylate onto the polylactide (PLA) chain via free‐radical polymerization. Fourier transform infrared spectroscopy and 1 H‐NMR were used to characterize the structure of the copolymer. Furthermore, PLA–GMA was used as a coupling agent to improve the interfacial adhesion between bamboo flour (BF) and PLA in PLA/BF biocomposites. The mechanical properties and crystallization behavior of the PLA/BF biocomposites were investigated. The results show that with the addition of PLA–GMA, the flexural strength and flexural modulus of the biocomposites increased significantly. The mechanical properties increased with increasing PLA–GMA amount. The PLA–GMA also enhanced the crystallization rate of PLA in the PLA/BF biocomposites. The property improvement of the biocomposites was due to enhanced interfacial adhesion between the PLA and BF. This was confirmed by scanning electron microscopy.