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Photophysical and Photochemical Effects of UV and VUV Photo- Oxidation and Photolysis on PET and PEN

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Photophysical and Photochemical Effects of UV and VUV Photo- Oxidation and Photolysis on PET and PEN Rochester Institute of Technology RIT Scholar Works Theses 1-2013 Photophysical and Photochemical Effects of UV and VUV Photo- Oxidation and Photolysis on PET and PEN Andrew Morgan Follow this and additional works at: https://scholarworks.rit.edu/theses Recommended Citation Morgan, Andrew, "Photophysical and Photochemical Effects of UV and VUV Photo-Oxidation and Photolysis on PET and PEN" (2013). Thesis. Rochester Institute of Technology. Accessed from This Thesis is brought to you for free and open access by RIT Scholar Works. It has been accepted for inclusion in Theses by an authorized administrator of RIT Scholar Works. For more information, please contact [email protected]. PHOTOPHYSICAL AND PHOTOCHEMICAL EFFECTS OF UV AND VUV PHOTO-OXIDATION AND PHOTOLYSIS ON PET AND PEN A Thesis Presented to the School of Chemistry and Materials Science and Engineering College of Science At Rochester Institute of Technology Rochester, New York 14623 In Partial Fulfillment of the Requirement for the Degree of Masters of Science in Materials Science & Engineering By: Andrew Morgan January 2013 CERTIFICATION OF APPROVAL PHOTOPHYSICAL AND PHOTOCHEMICAL EFFECTS OF UV AND VUV PHOTO-OXIDATION AND PHOTOLYSIS ON PET AND PEN By: Andrew Morgan __________________________________ __________________ Research Advisor Date Dr. Gerald A. Takacs Professor of Chemistry and Materials Science & Engineering __________________________________ __________________ Director D. KSV Santhanam Date Professor of Chemistry and Materials Science & Engineering i COPYRIGHT RELEASE FORM PHOTOPHYSICAL AND PHOTOCHEMICAL EFFECTS OF UV AND VUV PHOTO-OXIDATION AND PHOTOLYSIS ON PET AND PEN I, Andrew Morgan, hereby grant permission to the Wallace Memorial Library of the Rochester Institute of Technology to reproduce this thesis in its entirety or in part. Any reproduction will be with the intent to contribute to the proliferation of knowledge and understanding in the scientific community and will not be for commercial use or profit. ____________________________ __________________ Andrew Morgan Date ii DEDICATIONS I appreciatively dedicate my work to my family and friends. A genuine obliged sincerity to my loving and supportive parents, Maher and Hanaa Morgan for their care and provisions that led me to ultimately start and finish my Master's degree. A special feeling of appreciation to my sister, Heidi Morgan for her great emotional support. I would also like to thank my brother and my sister-in-law for their words of encouragement. I earnestly also appreciate the emotional and spiritual support of my friends and my church. iii ACKNOWLEDGMENT I would like to express my deepest and most sincere gratitude to my research advisor as well as my committee member, Dr. Gerald Takacs, whose patience and intelligence made my thesis possible. His support and accessibility allowed me to successfully finish my research. The advice and assistance facilitated my completion of this thesis, manuscript, and seminar presentation. I would also like to thank Dr. Matt Miri for his support and advice during my proposal. A special regards to the rest of my thesis committee members, Dr. Kalathur Santhanam and Dr. Alan Entenberg, for their honesty and integrity as well as their willingness to clear up their busy schedules to assess my research and thesis. A much deserved feelings of appreciation and regards to Dr. Tom Debies, Michael Mehan, Greg Thompson, and Xerox Corp. for their concise and timely XPS and SEM analysis. I would like to express my sincere gratitude for Tom Allston for his very important guidance with instrumentation and methods of analysis. I would finally like to thank all my research colleagues, Ryan Divens, Lisa Andrews, Ameya Khot, and Algis Naujokas for all their support and encouragement during my research. iv TABLE OF CONTENTS PAGE CERTIFICATION OF APPROVAL................................................................................i COPYRIGHT RELEASE FORM ...................................................................................ii DEDICATION..................................................................................................................iii ACKNOWLEDGMENT..................................................................................................iv TABLE OF CONTENTS..................................................................................................v LIST OF TABLES..........................................................................................................xiii LIST OF FIGURES.......................................................................................................xvii ABSTRACT...................................................................................................................xxvi 1 INTRODUCTION ......................................................................................................1 1.1 Surface modification versus bulk region reactions ...........................................1 1.2 Poly(Ethylene Terephthalate) (PET) ................................................................1 1.3 Poly(Ethylene 2,6-Napthalate) (PEN)...............................................................3 1.4 UV photo-oxidation reactions............................................................................4 1.5 UV photolysis reactions.....................................................................................6 1.6 Vacuum UV (VUV) plasma phase photo-oxidation .........................................6 1.7 Vacuum UV plasma phase photoreactions .......................................................7 1.8 Remote oxygen atom reactions..........................................................................8 1.9 Implications of bulk modifications of PET and PEN........................................9 1.10 Implications of surface modification for PET and PEN....................................9 2 RESEARCH OBJECTIVES.....................................................................................11 3 EXPERIMENTAL.....................................................................................................13 v 3.1 Materials..........................................................................................................13 3.1.1 Poly(ethylene terephthalate)......................................................................13 3.1.2 Poly(ethylene 2,6-naphthalate)..................................................................13 3.2 UV photoreactions...........................................................................................14 3.2.1 Atmospheric pressure UV photo-oxidation...............................................14 3.2.2 Atmospheric pressure UV photo-ozonation...............................................17 3.2.3 Atmospheric pressure UV photolysis........................................................20 3.3 Plasma photoreactions.....................................................................................21 3.3.1 VUV photo-oxidation................................................................................21 3.3.2 VUV photolysis.........................................................................................23 3.4 Remote oxygen reaction..................................................................................23 3.4.1 MW discharge of Ar and O2 mixture.........................................................23 3.4.2 MW discharge of Ar..................................................................................25 3.5 Analysis techniques.........................................................................................25 3.5.1 X-Ray Photoelectron Spectroscopy (XPS)................................................25 3.5.2 Scanning Electron Microscopy (SEM)......................................................28 3.5.3 UV Absorption Spectroscopy....................................................................29 3.5.4 FTIR...........................................................................................................32 3.5.5 Contact angle goniometry..........................................................................35 4 RESULTS...................................................................................................................37 4.1 XPS..................................................................................................................37 4.1.1 Untreated controls......................................................................................37 I PET control................................................................................................37 vi II PEN control................................................................................................38 4.1.2 UV photo-oxidation...................................................................................39 I. Atmospheric pressure 300 nm broad spectrum UV photo-oxidation of PET............................................................................................................39 II. Atmospheric pressure 253.7 nm UV photo-oxidation of PET...................41 4.1.3 Atmospheric pressure 184.9/253.7 nm UV photo-ozonation of PET.......43 4.1.4 UV photolysis............................................................................................46 I. Atmospheric pressure 300 nm broad spectrum UV photolysis of PET in nitrogen......................................................................................................46 II. Atmospheric pressure 253.7 nm UV photolysis of PET in
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