Importance of Statistical Factors in the Description of Kinetics of a Segmental Exchange in Polyester Systems. Re-Analysis of Reshuffling in PET/PEN Blends

摘要

The importance of implying statistical factors in the kinetic analysis of segmental exchange (reshuffling) in polyester systems is presented. Neglecting statistical factors in reshuffling, proceeding through direct reactions of ester groups located inside polyester chains, can lead to erroneous conclusions concerning the reactivity of ester bonds. This point of view is discussed and illustrated by re-analysis of some results of the recently reported simulation of reshuffling in poly (ethylene terephthalate)/poly(ethylene naphthalate) (PET/PEN) blends. The new analysis of this system, based only on the experimental data of the cited paper, gives estimates of the rate constants of two segmental exchange processes – interconversions of homo and hetero-dyads – determining the microstructure of the blending product. The estimated rate constants are in agreement with the thermodynamics of the copolymer microstructure, conforming to the microreversibility principle.