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Topologically Designed Cylindrical and Spherical Building TOPOLOGICALLY DESIGNED CYLINDRICAL AND SPHERICAL BUILDING BLOCKS TO CONSTRUCT MODULAR-ASSEMBLED STRUCTURES IN GIANT SHAPE-AMPHPHILES A Dissertation Presented to The Graduate Faculty of The University of Akron In Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy Jing Jiang May 2018 TOPOLOGICALLY DESIGNED CYLINDRICAL AND SPHERICAL BUILDING BLOCKS TO CONSTRUCT MODULAR-ASSEMBLED STRUCTURES IN GIANT SHAPE-AMPHPHILES Jing Jiang Dissertation Approved: Accepted: Advisor Department Chair Dr. Stephen Z. D. Cheng Dr. Coleen Pugh Committee Chair Dean of the College Dr. Toshikazu Miyoshi Dr. Eric J. Amis Committee Member Dean of the Graduate School Dr. Tianbo Liu Dr. Chand K. Midha Committee Member Date Dr. Yu Zhu Committee Member Dr. Chrys Wesdemiotis ii ABSTRACT Giant shape amphiphiles with isobutyl polyhedral oligomeric silsesquioxane (BPOSS) cages as the periphery at two discotic trisubstituted derivative of benzene cores were specifically designed and synthesized. Depending upon the number of BPOSS cages, these molecules first assembled into either cylindrical or spherical units via π-π interactions among the core unites. The packing of the molecules is mandated by the steric hindrance of the BPOSS cages at the periphery with hydrogen bonding interactions. If the space-packing is allowed, the cylindrical building block can form. Otherwise, the cylindrical building block will be forced to interrupt periodically and to form spherical building blocks. These units can further modular assemble into supramolecular structures. The cylindrical units form columnar structures with both hexagonal and rectangular packing, while the spherical units construct a Frank-Kasper A15 phase, similar to the metal alloy structures. In addition, based on the mechanism proposed by this work, five more giant shape amphiphiles with high steric hindrance on the periphery were synthesized, these giant shape amphiphiles successfully formed A15 phases with precisely size control, iii validating the reliability of this strategy. Formation of A15 phase based on nano-spherical building blocks offers a new pathway to design and construct new supramolecular phases and further functionalizes these structures. iv ACKNOWLEDGEMENTS First of all, I wish to express my deepest gratitude to my advisor, Prof. Stephen Z. D. Cheng for offering great opportunity for me to work as a graduate assistant in his group. I really appreciate his long-term encouragement, support, and inspiration. He is a person full of vision and led me towards the field I’ve never reached before. Instead of Polymer Science, I majored in Organic Chemistry during my undergraduate study, which is related to fundamental synthetic theories about small molecules. I never involved in any area related to the polymeric materials before he took me to be his student. In spite of the large gap between my background and his research directions, Dr. Cheng has always showed great confidence in me through those years, which was very important for me to conquer any difficulties in my experiments. He is always full of enthusiasm for the science. The way how he conducts himself also gave me a lot of inspiration. What I learn from him is that to be a professional researcher, one should continuously pursue mystery in science, not only focus on the basis of the problems but should also possess a keen insight into the frontier. This project was completely under his supervision and firmly support. From the v molecular design, sample preparation to data analysis, he gave me tremendous of advices and assistance. I also appreciate that he gave me enough guidance as well as equal level of freedom to choose my research directions and to design experiments. He is a considerate professor who will intentionally let you think about things instead of tell you how to do directly. Without his tremendous guidance and supports, none of the interesting results and conclusions in this dissertation can be possible. His great powder helped a lot of his students includes me. My sincere gratitude is expressed to him. I am very grateful to the dedicated committee members: Prof. Toshikazu Miyoshi, Prof. Tianbo Liu, Prof. Yu Zhu and Prof. Chrys Wesdemiotis. I truly appreciate their attendances in my Research Presentation and Defense, and their valuable comments and assistance that guided my research in this dissertation. I would like to express my deep gratitude especially to Prof. Bernard Lotz for his patient guidance of my research in crystallography. He is a teacher worth his salt. No matter how small the problem is, he will explain it to me clearly full of passion. Although he discussed with me for less than twenty times, his knowledge in crystal structure analysis had a huge influence on me and encouraged me to investigate the crystal structures. About one year ago, that is a hard time for me, I felt very depressed and worried about the possibility of finishing these projects. During that time Dr. Lotz visited our group during that time and talked to me very patiently. He has shown a very positive vi attitude to both of the research and life. Inspired by his spirits, I started to find a balance for me to solve problems instead of subjected to the worries. He is a person combined professional in science and enjoy of life together, I felt very lucky to have the chance discussing with him. I would also like to thank my group members, in particular, Dr. Kan Yue for sharing synthetic skills, Dr. Mingjun Huang for sharing physical analysis techniques, Dr. Chih-Hao Hsu for sharing structure determination and simulation skills during the beginning of my research. Special thanks are given to Dr. Yu Wang, Dr. Wei Zhang, and Mr. Shuailin Zhang for discussing the details in the project described in chapter four. Thanks Dr. Tao Li for shearing Synchrotron SAXS experiment beam time, Mr. Shan Mei for preparing carbon coated copper grid, Mr. Bo Ni for sharing microtome skills, Ms. Jialin Mao for the MALDI MS measurement, and Mr. Wenbin Yin for the IR measurement. Finally, I would like to thank my family members and friends for their endless supports, encouragement, and understanding during my pursuit of Ph.D. degree. I am deeply grateful to my parents and grandparents. Due to the One Child Policy in China, I am the only child in my family, my parents and grandparents give me selfless love since I was born. When I told them my plan to study abroad, my parents respected my choice and given me the best support immediately. For my grandparents, in spite of the fact that they vii do not want me to go so far away from home and these years I missed a lot of important things in their lives including the 80th birthday of my grandfather, they still love me. This gives me great power to overcome difficulties in finishing this dissertation. I am also deeply grateful to my boyfriend, Shuailin Zhang, for his support during my writing of this dissertation. When I felt upset and struggling with the tedious problems with myself, he is the person come and talk to me by sharing with his positive thoughts and some even worse situations, which made me feel not that bad. In summary, the journey of my pursuing the Ph.D. degree in the University of Akron is full of all kinds of explorations, challenges, improvements and love. I am very grateful to all the people that paricaipated in this important stage of my life. viii TABLE OF CONTENTS Page LIST OF SCHEMES .........................................................................................................xiv LIST OF FIGURES ..........................................................................................................xvi CHAPTER I. INTRODUCTION ............................................................................................................ 1 II. BACKGROUND ............................................................................................................. 5 2.1 Building from the Bottom Up ................................................................................ 5 2.1.1 Bottom-up Approach ................................................................................... 5 2.1.2 Soft Material ............................................................................................... 6 2.1.3 Bottom-up Construction of Soft Material ................................................... 8 2.2 Modular Giant Molecule ...................................................................................... 11 2.2.1 Nanoparticle – “Giant Atom”.................................................................... 11 2.2.2 Giant Surfactant ........................................................................................ 14 2.2.3 Giant Polyhedra ........................................................................................ 16 2.2.4 Giant Shape Amphiphile ........................................................................... 19 2.2.5 Precise Synthesis through Click Reactions ............................................... 20 ix 2.3 Disc Shape Molecule ........................................................................................... 24 2.3.1 π interaction Among Disc-shape Molecules ............................................. 24 2.3.2 Liquid Crystal (LC) Mesogens ................................................................. 26 2.3.3 Physical Properties and Applications ........................................................ 34 2.3.4 Triethynyl Benzene (TEB) ........................................................................ 42 2.3.5
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