Browse by author
Lookup NU author(s): Professor Paul ChristensenORCiD,
Dr Terry Egerton
Full text for this publication is not currently held within this repository. Alternative links are provided below where available.
Carbon dioxide evolution from poly(ethylene terephthalate) (PET) films during ultraviolet (UV) exposure has been monitored using FTIR interrogation of the atmosphere surrounding the test pieces. Measurement periods as little as 4 h could easily discriminate between CO2 emission rates when tests were conducted to investigate the effect of using different reaction atmospheres or of including UV absorber in the PET samples. Samples containing UV absorbers either homogeneously distributed through the film or in thin surface layers (similar to 0.7 mu m thick) were also tested. Relatively small reductions in CO2 emission rates were observed with samples containing UV absorbers but the rates were not very sensitive to the distribution and concentration of the absorbers. A thin surface layer containing only 2% stabiliser (equivalent to 0.23% stabiliser when averaged over the whole film thickness) provided oxidation reduction similar to that observed when 1% stabiliser was distributed evenly throughout the sample. Tests were conducted in wet oxygen, dry oxygen and dry nitrogen. For as-received bi-axially drawn PET film containing no absorber, the CO2 emission rate under UV illumination in wet oxygen was much higher than in dry oxygen or dry nitrogen. For as-received PET the difference between the rates observed in dry oxygen and dry nitrogen was small. For PET films that had been pre-exposed to UV (for 9 days) prior to insertion into the in situ CO2 measurement cell the rate of CO2 generation in oxygen was significantly larger than that in nitrogen. In both nitrogen and oxygen the presence of UV absorbers significantly decreased the rate of CO2 generation. (C) 2008 Elsevier Ltd. All rights reserved.
Author(s): Fechine GJM, Christensen PA, Egerton TA, White JR
Publication type: Article
Publication status: Published
Journal: Polymer Degradation and Stability
ISSN (print): 0141-3910
ISSN (electronic): 1873-2321
Publisher: Elsevier Ltd
Altmetrics provided by Altmetric