AN ANALYSIS OF CLIMATE-INDUCED DEGRADATION OF POLYPROPYLENE PRODUCTS
Publisher
The University of Arizona.Rights
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.Abstract
This work investigates degradation in polypropylene materials due to environmental exposure that is typical of late spring in Tucson, Arizona. Examination of the results enables the pattern of degradation to be quantified and related to mechanisms of degradation. Specifically, polypropylene samples were exposed to typical Tucson solar spectrum radiation, humidity, and temperatures in an environmental chamber that has been calibrated for testing solar panels in southern Arizona climate equivalents. Pre- and post-exposure masses, brittleness, and UV-visible and FTIR (Fourier Transform Infrared) spectra were collected for each sample, as well as for the control suite of samples that were preserved in their as-received condition, without any environmental exposure. Results show significant degradation leading to total material failure and disintegration in as few as ten days in many of the tested samples, as suggested by significantly increased brittleness, loss of mass, and the formation of a carbonyl signature. The rate of degradation for these same samples without solar radiation has also been shown to be significantly diminished; at ten days of exposure, brittleness, mass, and the spectra were consistent with the control samples and the initial sample data pre-exposure. This has significant consequences for any groups that work with polypropylene materials, and it illustrates that light exposure is the most significant factor in polypropylene degradation in a southern Arizona climate.Type
Electronic thesistext
Degree Name
B.S.Degree Level
bachelorsDegree Program
ChemistryHonors College