Abstract: TPET regenerated from used polyester textiles and native polyester were used as raw materials and their respective degradation-rheological behavior was studied by using Rosand RH-7 capillary rheometer. The results showed that after the degradation process at certain temperature, both materials showed a typical pseudoplastic flow behavior. Compared with native polyester, the regenerated polyester started degrading at a lower temperature, and the degradation occurred mainly within the first 5 min. of the degradation process. With the increase of shear rate or the retention time of the degradation treatment, the △Eη of both polyesters was found decreasing. Compared with the native polyester, the structural viscosity index of the regenerated polyester was relatively higher, predicting that the regenerated polyester would exhibit poor spinnability in the melt spinning process.

Key words: waste polyester textiles; regenerated polyester; degradation-rheological behavior; flow activation energy; structural viscosity index