Study of Microwave Selective Action on Polyester Hydrolytic Depolymerization

The hydrolytic depolymerization of Polyethylene terephthalate (PET)and polybutylece terephthalate (PBT) under microwave irradiation is studied in this paper. The experimental results for PET and PBT are compared for samples processed at 2MPa for 120 min, at 800W and with weight ratio of water to PET of 10 : 1. PET completely depolymerized to terephthalate acid(TPA) and ethylene glycol(EG). However, the maximum degree of PBT depolymerization only 1.59%. The results indicate that microwaves are highly selective in activating reaction pathways. When compare with traditional heating methods, there are clearly non-thermal effects contributing to the microwave depolymerization of PET.