The solvent transport in poly(ethylene terephthalate) (PET) and related phenomena were investigated. Based on Harmon’s model for Case I (Fickian), Case II (swelling) and anomalous transport, the data of mass uptake were analyzed. Pure Case I or Case II behavior did not appear in our study and is affected by the annealing atmospheres and the preheating environments. The mass transport in PET is accompanied by a large-scale structural rearrangement, which leads to the induced crystallization of the original amorphous state. During this process, the matrix is under compressive stress. Solvent-induced crystallization was confirmed by X-ray diffraction (XRD), Differential Scanning Calorimeter (DSC), which is quite different from the thermal crystallization. The different behaviors of sorption between the solvent-treated PET crystallites and thermally treated PET can be explained in terms of the results of XRD, DSC and density measurement.
Посилання на статтю:
The mass transport in poly(ethylene terephthalate) and related induced-crystallization / Hao Ouyang, Shyh-Horng Shore // Polymer. – 1999. – N 40. – P. 5401–5406.