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Design and Fabrication of Transparent Polycarbonate/Carbon Nanotube Composite Films Yuan-Chen (Craig) Chin

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Design and Fabrication of Transparent Polycarbonate/Carbon Nanotube Composite Films Yuan-Chen (Craig) Chin Florida State University Libraries Electronic Theses, Treatises and Dissertations The Graduate School 2007 Design and Fabrication of Transparent Polycarbonate/Carbon Nanotube Composite Films Yuan-Chen (Craig) Chin Follow this and additional works at the FSU Digital Library. For more information, please contact [email protected] THE FLORIDA STATE UNIVERSITY FAMU-FSU COLLEGE OF ENGINEERING DESIGN AND FABRICATION OF TRANSPARENT POLYCARBONATE/CARBON NANOTUBE COMPOSITE FILMS By YUAN-CHEN (CRAIG) CHIN A Thesis submitted to the Department of Industrial Engineering in partial fulfillment of the requirements for the degree of Master of Science Degree Awarded: Spring Semester 2007 The members of the Committee approve the thesis of Yuan-Chen Chin defended on 04/12/2007. _____________________ Young-Bin Park Professor Directing Thesis _____________________ Ben Wang Committee Member _____________________ Zhiyong Liang Committee Member _____________________ Okenwa Okoli Committee Member Approved. ______________________________________________________________ Chuck Zhang, Chair, Department of Industrial and Manufacturing Engineering ______________________________________________________________ C. J. Chen, Dean, College of Engineering The Office of Graduate Studies has verified and approved the above named committee members. ii ACKNOWLEDGEMENTS I am most appreciative of my advisor, Dr. Young-Bin Park. He always earnestly and persistently urged and supported me in my graduate study despite of the set-backs and frustrations hindering my progress. I also would like to thank my committee members, Dr. Ben Wang, Dr. Zhiyong Liang and Dr. Okenwa Okoli for the encouragement and helpful suggestions to my research. Moreover, department chair, Dr. Chunk Zhang, has always kept supporting me in my extended research. Additionally, I would like to acknowledge the post-doctors, Dr. Jin-Gyu Park, Dr. Qiang Wu for their instruction in the instruments; the administrative staff, Mrs. Stephanie Dickey, Mr. James Horne, and Mr. Qing (Charlie) Liu for their assistance in administration; also, Giang Pham, Eric Rodriguez, Evin Chen, Ashley Liao, Edward Wang, Irene Yeh, Charlie Lin, Kenny Tsai, Daphne Ku, Vavinlen Chen and all my co-workers at High-Performance Materials Institute (HPMI) for their help and encouragement to me. I also would like to acknowledge Mr. Han Gi Chae at Georgia Tech for his helpful discussions on PC crystallization and transparency analysis, and the Army Research Lab for their valuable assistance and contribution in my research. Lastly, I would like to give special thanks to my family for their supporting and emboldening me to finish my study. iii TABLE OF CONTENTS LIST OF TABLES ........................................................................................................... vi LIST OF FIGURES ........................................................................................................ vii ABSTRACT....................................................................................................................... x CHAPTER 1 MOTIVATION AND OBJECTIVES..................................................... 1 1.1 Introduction............................................................................................................... 1 1.2 Current State of the Transparent Materials............................................................... 1 1.3 General Problem Statements..................................................................................... 3 CHAPTER 2 BACKGROUND AND LITERATURE REVIEW................................ 5 2.1 The Optical Principles and Basics ............................................................................ 5 2.1.1 The Optical Principles and Basics ..................................................................... 5 2.1.2 Numerical Calculation ....................................................................................... 8 2.1.3 The Effect of Crystallization on Transparency.................................................. 9 2.1.4 Microphysics.................................................................................................... 10 2.2 Chemistry and Properties of Polycarbonate............................................................ 11 2.2.1 Driving Forces for Polymer Crystallization..................................................... 13 2.2.2 Measurement of Degree of Crystallization...................................................... 13 2.3 Carbon Nanotubes as Toughening Agents.............................................................. 14 2.2.1 General Properties of Carbon Nanotubes ........................................................ 14 2.2.2 Toughening Mechanisms of CNT Composites................................................ 15 2.3 Methods for PC/CNT Composite Fabrication ........................................................ 18 2.3.1 Melt Processing................................................................................................ 18 2.3.2 Solution Processing.......................................................................................... 19 2.3.3 Electrospinning ................................................................................................ 20 2.4 Characterization of PC/CNT Composites............................................................... 21 2.4.1 CNT Toughening Mechanism.......................................................................... 21 2.4.2 Optimal CNT Loading for Enhancing Mechanical Properties ........................ 23 2.4.2 Optical Properties............................................................................................. 25 2.4.3 Haze and Luminous Transmittance ................................................................. 26 2.4.3 Differential Scanning Calorimetry (DSC) Technique ..................................... 27 2.4.3 Impact and Ballistic Resistance ....................................................................... 29 2.5 Summary of Literature Review............................................................................... 30 2.6 Research Objectives................................................................................................ 30 CHAPTER 3 FABRICATION AND CHARACTERIZATION OF NEAT POLYCARBONATE FILMS ........................................................................................ 32 3.1 Introduction............................................................................................................. 32 3.2 Transparent Neat PC Film Fabrication ................................................................... 32 3.3 Design and Analysis of Experiments for the Degree of Crystallization................. 35 3.3.1 Solution Casting Factor Selection.................................................................... 35 3.4 DOE Analysis Results and Discussions.................................................................. 40 3.4.1 Driving Forces for Polymer Crystallization..................................................... 40 iv 3.4.2 DOE Analysis .................................................................................................. 41 3.4.3 Optimization and Discussions.......................................................................... 45 3.5 Summary................................................................................................................. 47 CHAPTER 4 FABRICATION OF TRANSPARENT PC/MWNT COMPOSITE FILMS.............................................................................................................................. 49 4.1 Introduction............................................................................................................. 49 4.2 Fabrication of Transparent PC/MWNT Composite Films...................................... 49 4.3 Summary................................................................................................................. 50 CHAPTER 5 OPTICAL PROPERTIES OF PC/MWNT COMPOSITE FILMS... 53 5.1 Introduction............................................................................................................. 53 5.2 Characterization of CNT Dispersion by Optical Microscopy................................. 54 5.3 UV-Visible Spectrometry ....................................................................................... 55 5.3.1 The Beer-Lambert Law.................................................................................... 56 5.3.2 UV-Visible Property ........................................................................................ 58 5.4 Differential Scanning Calorimetry (DSC) Analysis ............................................... 62 5.5 Scanning Electron Microscopy (SEM) Analysis .................................................... 66 5.6 PC/MWNT Composite Film Thickness Analysis................................................... 68 CHAPTER 6 MECHANICAL PROPERTIES OF PC/CNT COMPOSITE FILMS ........................................................................................................................................... 71 6.1 Review .................................................................................................................... 71 6.2 Mechanical Properties of PC/CNT Films ............................................................... 71 6.2.1 Experimental.................................................................................................... 71 6.2.2 Experiment Results .........................................................................................
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