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Living Radical Polymerization Catalysts PDF

216 Pages·2016·8.62 MB·English
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University of Pennsylvania ScholarlyCommons Publicly Accessible Penn Dissertations Winter 12-21-2011 Living Radical Polymerization Catalysts: Synthesis, Application, and Utilization of Polymer Products in the Synthesis of Metal Nanoparticles Sara E. Hayik University of Pennsylvania, Living Radical Polymerization Catalysts: Synthesis, Application, and Utilization of Polymer Products in the Synthesis of Metal Nanoparticles Abstract Living Radical Polymerization Catalysts: Synthesis, Application, and Utilization of Polymer Products in the Synthesis of Metal Nanoparticles Sara Elizabeth Hayik Supervisor: Professor Bradford B. Wayland Living radical polymerization techniques are powerful tools for prepared specialty polymer products used in applications from biotechnology to electronics. Development of catalysts for the diferent methods is important for increased versatility. Te goals of this research were to develop new radical addition- fragmentation chain transfer (RFT) and cobalt mediated radical polymerization (CMRP) catalysts and utilize polymers produced through controlled radical polymerization techniques for the synthesis of metal nanoparticles. Vanadium complexes were designed to mimic conventional RFT chain transfer agents and tested in the polymerization of methylacrylate (MA) and styrene. Tese complexes proved unsuitable for use as RFT catalysts. Several cobalt complexes, using salen and salen derivative ligands, were prepared and tested as CMRP catalysts for the polymerization of MA and vinyl acetate (VAc). (R,R)-N,N'-Bis(3,5-di-tert- butylsalicylidene)-1,2-cyclohexanediamino Cobalt (II) proved to be the most promising candidate for both polymers. MA was prepared with PDIs 1.32 and under while the VAc PDIs were under 1.50. In both cases, observations suggesting a controlled polymerization were reported. PDMAEMA synthesized using a RFT polymerization was used to stabilize and control the formation of platinum, gold, and palladium nanoparticles. Protonation of the polymer chains using succinic acid or acidic metal complexes allowed for ionic cross-linking by the metal anions, which is observed through DLS analysis. Reduction of the metal complexes was then performed within the nanogel and the rapid stabilization by the polymer results in small well defned particles. Well defned particles were produced for each metal with diferent size ranges for each. Nanogel formation is critical mechanism for control in each system and was seen only in systems containing dianionic species Degree Type Dissertation Degree Name Doctor of Philosophy (PhD) Graduate Group Chemistry First Advisor Dr Bradford B. Wayland Tis dissertation is available at ScholarlyCommons: htp://repository.upenn.edu/edissertations/437 Keywords living radical polymerization, metal nanoparticles, polymerization, nanogel, LRP catalysts Subject Categories Inorganic Chemistry Tis dissertation is available at ScholarlyCommons: htp://repository.upenn.edu/edissertations/437 LIVING RADICAL POLYMERIZATION CATALYSTS: SYNTHESIS, APPLICATION, AND UTILIZATION OF POLYMER PRODUCTS IN THE SYNTHESIS OF METAL NANOPARTICLES Title Page Sara Elizabeth Hayik A DISSERTATION In Chemistry Presented to the Faculties of the University of Pennsylvania In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy 2011 Supervisor of Dissertation _____________________________ Bradford B. Wayland, Professor of Chemistry Graduate Group Chairperson _____________________________ Gary A. Molander, Professor of Chemistry Dissertation Committee Larry G. Sneddon, Professor of Chemistry Christopher Murray, Professor of Chemistry So-Jung Park, Assistant Professor of Chemistry LIVING RADICAL POLYMERIZATION CATALYSTS: SYNTHESIS, APPLICATION, AND UTILIZATION OF POLYMER PRODUCTS IN THE SYNTHESIS OF METAL NANOPARTICLES COPYRIGHT 2011 Sara Elizabeth Hayik Dedication To my family and friends, I would have never made it without you. iii Acknowledgements First I would like to thank my dissertation advisor Dr. Bradford Wayland. Dr. Wayland allowed me the freedom to grow as scientist, teacher and person. I am extremely grateful for his guidance throughout my graduate experience and for the introduction to a field in which I had no experience. Dr. Wayland provided me with the opportunity to find a path to teaching without which I would never have found what I believe is my true calling. I would also like to thank Dr. Mike Fryd who provided both personal and scientific support. Mike introduced me to the world of nanotechnology and was always there to challenge my assumptions. Mike’s optimism was always welcome in the face of unexpected results. This characteristic has forever changed my scientific viewpoint leading me down the path of how and why versus just looking at the whats. I sincerely appreciate all of the time that my dissertation committee has given to my endeavor. Dr. Larry Sneddon, Dr. So-jung Park, and Dr. Chris Murray have all provided me with an excellent support system and have asked excellent and challenging questions. I would also like to thank Dr. Michael Therien who served on my committee in the early stages of my work. The support staff of the University of Pennsylvania Chemistry department is superb. I would especially like to thank Bruce and Rico for always being there to fix the lab, move heavy items, or just for a talk. Mandy Swope provided an incredible amount of guidance as I planned these final few steps and without her I would have been helpless. Andre and Cong were always there to brighten my day on trips to the stockroom and Tommy Nguyen kept all of my teaching responsibilities in line. Dr Susan Phillips provided me with incredible teaching freedom. I will forever be extremely grateful for this opportunity. I entered graduate school terrified of teaching and left a teacher. Sue’s incredible support and trust gave me this confidence and completely changed my future. I could not have asked for better classmates without whom I do not believe I could have made it through the trials and tribulations of the last few years. Dr. Dan Himmelberger, Dr. Julie iv Aaron, Dr. Ian Farrell, Diana (Cabral) Challen provided me with some of my best times at Penn at lunches, Dining Days, Livestrong, and the many wonderful celebrations including my wedding. Dr Fernando Jove, Dr. Sounak Sarkar, and Dr Chi-How Peng were fantastic groupmates. I would also like to thank the members of the Sneddon group especially Ariane Perez-Gavilin and Emily Berkley, who provided me with both entertainment and help throughout my stay on the third floor. Jen Scricco welcomed me into the group and guided me in the infancy of my research. I would like to express my sincere gratitude to Amanda Kamps who performed the TEM imagining of my nanoparticle without which my work would not have been complete. I would also like to thank Amanda and Sean for all of the hours of nerd games. I would like to thank Dr. Andre Isaacs, Xi- Jun Chen, Rob Hickey, Dierdre Sandrock, Ben Dyme, and Daniell Reifsnyder for their friendship. The love of chemistry does not begin in college so I would like to thank Mrs Teri Miller for introducing me to chemistry in high school. Mrs. Miller’s excitement and wonderful teaching gave me the spark to further pursue the field. The opportunities I was given in high school were well beyond the expected and for that I am extremely grateful. I am also so appreciative of her patience since I know I was not always the best student. Dr. Edward Rajaseelan took the spark and turned it into a flame during my time at Millersville University. I have never met a teacher who is his equal and I can only hope to someday be a fraction of what he was to me to my own students. Dr. R. saw in me what I did not see in myself and for that I am forever grateful. I would like to thank my family who have always supported me. My in-laws Joe and Winnie have been supportive of both Seth and I throughout the graduate school process. A love of science, exploration, and science were seeded early in me by my Grandma Nichols, persistence seems to be a family trait handed down through my GrammyDoris, and all of my grandparents have provided unwavering support of my somewhat untraditional path. My parents, Sheila and Dave, may never have understood what I was doing scientifically but were always there for me in the ups and downs of graduate school. My brothers, Keith and Jeremy, never let v me get a big head but were always there especially Keith who saved me from so very many car disasters. Yes I am finally done with that paper everyone! Finally I would like to thank Seth who has been the proofreader, the motivator, the sounding board, and every other niche I have needed filled. I know I have not always made it easy for him but I know I would have never made it this far without his patience, guidance, and most of all his love. I will also always appreciate him letting us get our three cats who have been ever so helpful writing my dissertation. Seth has always let me go with my crazy projects no matter the inconvenience, including the huge piles of dissertation materials all over the house. Seth and I have grown up as a couple together from awkward teenagers to what feels like an old married couple. We have come so far and made it through so much and I cannot wait to see what our future holds. Thank you, thank you, thank you! vi Abstract LIVING RADICAL POLYMERIZATION CATALYSTS: SYNTHESIS, APPLICATION, AND UTILIZATION OF POLYMER PRODUCTS IN THE SYNTHESIS OF METAL NANOPARTICLES Sara Elizabeth Hayik Supervisor: Professor Bradford B. Wayland Living radical polymerization techniques are powerful tools for prepared specialty polymer products used in applications from biotechnology to electronics. Development of catalysts for the different methods is important for increased versatility. The goals of this research were to develop new radical addition-fragmentation chain transfer (RAFT) and cobalt mediated radical polymerization (CMRP) catalysts and utilize polymers produced through controlled radical polymerization techniques for the synthesis of metal nanoparticles. Vanadium complexes were designed to mimic conventional RAFT chain transfer agents and tested in the polymerization of methylacrylate (MA) and styrene. These complexes proved unsuitable for use as RAFT catalysts. Several cobalt complexes, using salen and salen derivative ligands, were prepared and tested as CMRP catalysts for the polymerization of MA and vinyl acetate (VAc). (R,R)-N,N'- Bis(3,5-di-tert-butylsalicylidene)-1,2-cyclohexanediamino Cobalt (II) proved to be the most promising candidate for both polymers. MA was prepared with PDIs 1.32 and under while the VAc PDIs were under 1.50. In both cases, observations suggesting a controlled polymerization were reported. PDMAEMA synthesized using a RAFT polymerization was used to stabilize and control the formation of platinum, gold, and palladium nanoparticles. Protonation of the polymer chains using succinic acid or acidic metal complexes allowed for ionic cross-linking by the metal anions, which is observed vii

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Most books are stored in the elastic cloud where traffic is expensive. For this reason, we have a limit on daily download.