Effect of phosphate on the thermal properties of poly(ethylene naphthalate)/poly(ethylene terephthalate) blends

Abstract

The effect of organic phosphate as a transesterification inhibitor on transesterification reaction in poly(ethylene 2,6-naphthalate)poly(ethylene terephthalate) [PEN/PET] blends has been studied. Thermal properties of PEN/PET blends were also investigated as a function of processing conditions and the existence of organic phosphate. The level of transesterification reaction in PEN/PET blends decreased with the addition of organic phosphate as small as 0.3 wt%. Transesterification reaction in PEN/PET blends started at 220 degrees C and this temperature did not change by adding organic phosphate. The transesterification reaction caused the decrease of melting temperature and the increase of glass transition temperature and cold crystallization temperature of the PEN/PET blends. Adding organic phosphate as a transesterification inhibitor and a nucleating agent for crystallization resulted in increase of melting temperature and decrease of glass transition temperature in PEN/PET blends.