Abstract: The degradation and crystallization behavior of poly(ethylene terephthalate) under different meltmixing conditions were investigated. PET chips were degraded to various degrees at different pretreatment conditions. The degradation rate was closely related to the water content; degradation not only led to an improvement of crystallization rate, but also resulted in a thickening of crystal lamella and increase of crystallinity. The crystallization peak temperature (Tcp), initial temperature (Tonset), end temperature (Tendset), and intrinsic viscosity showed good correlations. When intrinsic viscosity decreased, those temperature and crystallization rate increased.

Key words: poly(ethylene terephthalate), degradation, intrinsic viscosity, crystallization