Crystallization kinetics of poly(ethylene terephthalate)/Poly(ethylene 2,6-naphthalate) blends

The crystallization kinetics of poly(ethylene terephthalate)/poly(ethylene 2,6-naphthalate) (PET/PEN) blends were investigated by DSC: as functions of crystallization temperature, blend composition, and PET and PEN source. Is othermal crystallization kinetics were evaluated in terms of the Avrami equ ation. The Avrami exponent (n) is different for PET, PEN, and the blends, i ndicating different crystallization mechanisms occurring in blends than tho se in pure PET and PEN. Activation energies of crystallization were calcula ted from the rate constants, using an Arrhenius-type expression. Regime the ory was used to elucidate the crystallization course of PET/PEN blends as w ell as that of unblended PET and PEN. The transition from regime II to regi me III was clearly observed for each blend sample as the crystallization te mperature was decreased. (C) 2001 John Wiley & Sons, Inc.