Chain structure and thermal behavior of reactive blends of poly(ethylene terephthalate)/poly(butylene terephthalate) by addition of 2,2 '-(1,4-phenyl) bisoxazoline

The chain structure and thermal behavior of reactive blends of poly(ethylen e terephthalate) (PET) with poly(butylene terephthalate) (PET) by 2,2'-(1,4 -phenyl) bisoxazoline (PBO) were studied in detail. The C-13 NMR results in dicate that the chain structures of the reactive blends are significantly a ffected by the mixing time and temperature owing to transesterification. Th e transesterification can be accelerated in the presence of PBO, especially when the mixing temperature is above 270 degrees C, As a consequence, the chain structure, and in turn, the crystallization behavior both From the gl assy and melt states and the melting behavior are significantly changed. (C ) 2000 Elsevier Science Ltd. All rights reserved.