Reactive compatibilization of polyolefin/PET blends by melt grafting with glycidyl methacrylate

The melt free radical grafting of glycidyl methacrylate (GMA) onto high-density polyethylene (HDPE) was carried out in Brabender internal mixer. The GMA content of the grafted HDPE (HDPE-g-GMA) was determined through FTIR by means of a calibration curve. The influence of reaction procedure, radical initiator concentration and addition of a co-monomer (styrene) on the grafting efficiency was examined. Blends of poly(ethylene terephthalate) (PET) with HDPE and HDPE-g-GMA (75/25 w/w) were prepared by melt mixing in internal mixer. The morphology of the blends was then analysed by SEM microscopy. PET/HDPE-g-GMA blends displayed improved phase dispersion and interfacial adhesion as compared to unfunctionalized PET/HDPE blend.