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Predictive Lifetime Models of Polymer Insulation Degradation and Biorenewable Thermosets Through Cati

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Predictive Lifetime Models of Polymer Insulation Degradation and Biorenewable Thermosets Through Cati Iowa State University Capstones, Theses and Graduate Theses and Dissertations Dissertations 2013 Polymer damage mitigation--predictive lifetime models of polymer insulation degradation and biorenewable thermosets through cationic polymerization for self-healing applications Peter Raymond Hondred Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/etd Part of the Mechanics of Materials Commons Recommended Citation Hondred, Peter Raymond, "Polymer damage mitigation--predictive lifetime models of polymer insulation degradation and biorenewable thermosets through cationic polymerization for self-healing applications" (2013). Graduate Theses and Dissertations. 13105. https://lib.dr.iastate.edu/etd/13105 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Polymer damage mitigation—predictive lifetime models of polymer insulation degradation and biorenewable thermosets through cationic polymerization for self- healing applications by Peter Raymond Hondred A dissertation submitted to the graduate faculty in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Major: Materials Science and Engineering Program of Study Committee: Michael R. Kessler, Major Professor Nicola Bowler Mufit Akinc Xiaoli Tan Malika Jefferies-El Iowa State University Ames, Iowa 2013 ii TABLE OF CONTENTS LIST OF TABLES ................................................................................................................... vi LIST OF FIGURES ................................................................................................................ vii ACKNOWLEDGEMENTS ...................................................................................................... x ABSTRACT ............................................................................................................................ xii CHAPTER 1: GENERAL INTRODUCTION ......................................................................... 1 1.1 Introduction ............................................................................................................. 1 1.2 Dissertation Organization ....................................................................................... 2 1.3 Thermal Degradation Kinetics and Lifetime Prediction Modeling of Wire Insulations ..................................................................................................................... 4 1.3.1 Motivation and Literature Review ........................................................ 4 1.3.2 Theory ................................................................................................... 6 1.3.3 Research Objective ................................................................................ 9 1.4 Biorenewable Polymers for Self-healing Application .......................................... 10 1.4.1 Motivation ........................................................................................... 10 1.4.2 Literature Review ................................................................................ 12 1.4.3 Research Objective .............................................................................. 16 1.5 References ............................................................................................................. 18 CHAPTER 2: DEGRADATION KINETICS OF POLYTETRAFLUOROETHYLENE (PTFE) AND POLY(ETHYLENE-ALT-TETRAFLUOROETHYLENE) (ETFE) ....... 24 2.1 Abstract ................................................................................................................. 24 2.2 Introduction ........................................................................................................... 24 2.3 Materials & Preparation ........................................................................................ 27 2.4 Methods................................................................................................................. 28 2.5 Kinetic Modeling .................................................................................................. 28 iii 2.6 Results and Discussion ......................................................................................... 31 2.7 PTFE Model .......................................................................................................... 42 2.8 ETFE Model.......................................................................................................... 44 2.9 Conclusions ........................................................................................................... 46 2.10 Acknowledgements ............................................................................................. 47 2.11 References ........................................................................................................... 47 CHAPTER 3: DEGRADATION KINETICS OF POLYIMIDE FILM ................................. 49 3.1 Introduction ........................................................................................................... 49 3.2 Materials & Preparation ........................................................................................ 51 3.3 Methods................................................................................................................. 51 3.4 Kinetic Modeling .................................................................................................. 52 3.5 Results & Discussion ............................................................................................ 57 3.6 Conclusions ........................................................................................................... 70 3.7 Acknowledgements ............................................................................................... 70 3.8 References ............................................................................................................. 71 CHAPTER 4: ELECTROTHERMAL LIFETIME PREDICTION OF POLYIMIDE WIRE INSULATION WITH APPLICATION TO AIRCRAFT .................................... 73 4.1 Abstract ................................................................................................................. 73 4.2 Introduction ........................................................................................................... 73 4.3 Materials & Preparation ........................................................................................ 76 4.4 Methods................................................................................................................. 77 4.5 Thermogravimetric Theory ................................................................................... 78 4.6 Lifetime Theory .................................................................................................... 80 4.7 Thermogravimetric Analysis ................................................................................ 82 4.8 Electrical Breakdown Analysis ............................................................................. 86 4.9 Lifetime Prediction ............................................................................................... 87 4.10 Discussion ........................................................................................................... 88 4.11 Conclusion .......................................................................................................... 91 4.12 Acknowledgments............................................................................................... 91 iv 4.13 References ........................................................................................................... 92 CHAPTER 5: TUNG OIL-BASED THERMOSETTING POLYMERS FOR SELF- HEALING APPLICATION ............................................................................................ 95 5.1 Abstract ................................................................................................................. 95 5.2 Introduction ........................................................................................................... 96 5.3 Materials ............................................................................................................... 98 5.4 Synthesis ............................................................................................................. 100 5.5 Results and Discussion ....................................................................................... 103 5.6 Conclusion .......................................................................................................... 115 5.7 References ........................................................................................................... 116 CHAPTER 6: RARE EARTH TRIFLATE INITIATORS IN THE CATIONIC POLYMERIZATION OF TUNG OIL-BASED THERMOSETTING POLYMERS FOR SELF-HEALING APPLICATIONS ..................................................................... 119 6.1 Abstract ............................................................................................................... 119 6.2 Introduction ......................................................................................................... 120 6.3 Materials ............................................................................................................
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