Post-consumer polyethylene terephthalate (PET)/ polyolefin blends through reactive processing

Increasing awareness of environmental and\nenergy problems has promoted greater governmental interest\nin selected waste collection and consequently has\nattracted the interest of several research groups to the challenge\nof converting recovered plastics into useful materials.\nThe reactive blending of postconsumer polyethylene\nterephthalate (PET) with different polyolefins (PO) was\nstudied in attempts to obtain a new material with enhanced\nproperties with respect to the starting materials.The success\nof the project depends mainly on the possibility of obtaining\na compatibilized blend between two starting polymers\nthat, from chemical and thermomechanical viewpoints, are\nvery different. This was approached by employing polyolefins\nbearing functional groups capable of specific interaction\nor chemical reaction with PET end groups. Ternary\nblends of very low density polyethylene (VLDPE)/PET/\nfunctionalized polyolefin (FPO) in a weight composition of\n70/20/10 and binary blends of FPO/PET in a weight composition\nof 90/10 were prepared and studied to obtain\nreinforced polyolefin thermoplastic materials. Reactive\nblending was achieved in a Brabender Plastograph with a\nmixing chamber of 30 or 50cm3, at 250°C, and 40rpm for\n10min. Differential scanning calorimetry, scanning electron\nmicroscopy, and tensile tests were used to investigate the\nphase behavior, the efficiency of compatibilization, and the\nmechanical properties of the blends.