Structural Changes of Crystalline Fine Textures During Aminolysis of Poly (Ethylene Terephthalate) Films

Abstract

A study was made of the morphological changes of crystalline fine texture that occurred when poly(ethylene terephthalate) films were degraded in aqueous ethylamine at room temperature. Earlier works proposed that photomicrographies applied to the investigation of the etching patterns were sensitive technique to detect the differences of orientation anisotropy and amounts of crystallinity for PET films which had different mechanical and thermal history. In the present work X-ray measurements were used to deduce the information on the occurring of the various etching patterns based on the structural changes of the crystallite orientation, the size of crystallite, the long period spacing and the distributions of the size of laminar domains by the degradation of films.

Aminolysis of polyesters for cracking and structure clarifying: A review

“…In the subject of degraded polyester morphology determination, 110–145 several analytical techniques have been used by researchers to reveal the elements of the changes. These techniques include microscopy, gel permeation chromatography, X‐ray diffraction, spectroscopy, and so on.…”

“…The samples had different thermal and mechanical histories. The etching patterns were related to the crystallite orientation determined by the X‐ray diffraction technique 118 …”

“…The samples had different thermal and mechanical histories. The etching patterns were related to the crystallite orientation determined by the X-ray diffraction technique 118. A combination of the aminolysis and gel permeation chromatography was used to examine the reaction of bulk PET with 40% aqueous methylamine at 35 C. The crystalline fold period was found to be six to nine monomer units over the crystallization temperature range of 126-229 C and the reagent was selective enough to separate amorphous and crystalline regions.…”