Please use this identifier to cite or link to this item:
Type: Artigo de periódico
Title: Poly (ethylene terephthalate) thermo-mechanical and thermo-oxidative degradation mechanisms
Author: Romao, W
Franco, MF
Corilo, YE
Eberlin, MN
Spinace, MAS
De Paoli, MA
Abstract: (1)H NMR and MALDI-TOF MS measurements were used to study the thermo-mechanical and thermo-oxidative degradation mechanisms of bottle-grade PET (btg-PET). In the thermo-oxidative degradation, the concentration of low molar mass compounds increased with time and the main products were cyclic and linear di-acid oligomers. In the thermo-mechanical degradation, the main-chain scission reactions affect the stability of the cyclic oligomers. One of the most important bottle-grade PET co-monomers is diethylene glycol (DEG), which is a 'reactive site' in the thermal degradation of btg-PET. The DEG co-monomer was shown to be the precursor to colour changes in btg-PET, owing to the attack by molecular oxygen on the methylenic protons adjacent to the ether oxygen atoms of DEG. This behaviour was observed in the thermo-oxidative degradation process in which the degradation of DEG causes the release of hydroxyl radicals in the polymeric matrix, thereby producing mono- and di-hydroxyl substituted species. This was also observed in the thermo-mechanical degradation process. (c) 2009 Elsevier Ltd. All rights reserved.
Subject: Poly(ethylene terephthalate)
Thermo-oxidative degradation
Thermo-mechanical degradation
Diethylene glycol
(1)H NMR
Country: Inglaterra
Editor: Elsevier Sci Ltd
Citation: Polymer Degradation And Stability. Elsevier Sci Ltd, v. 94, n. 10, n. 1849, n. 1859, 2009.
Rights: fechado
Identifier DOI: 10.1016/j.polymdegradstab.2009.05.017
Date Issue: 2009
Appears in Collections:Unicamp - Artigos e Outros Documentos

Files in This Item:
File Description SizeFormat 
WOS000273019300029.pdf900.55 kBAdobe PDFView/Open

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.