Electrochemically Controlled Atom Transfer Radical Polymerization and Synthesis of Polymers with Complex Architectures
Creators: name: Sangwoo  Park
Publisher: name: Carnegie Mellon University
Year: 2016
Subjects: subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: FOS: Chemical sciences

description: Atom transfer radical polymerization (ATRP) is one of the most broadly applied reversible deactivation radical polymerization (RDRP) technique that provide well-defined polymers with predetermined molecular weight (MW) and narrow molecular weight distribution (MWD). The functional polymers synthesized by ATRP showed a potential promise in the fields of biomedical applications such as smart drug delivery, tissue engineering, and diagnostic sensors. In general, conventional ATRP requires a large amount of transition metal catalysts (&gt; 1000 parts per million (ppm) versus molar ratio of monomers) and removal of the residual catalysts is necessary for use of advanced materials in bio-applications. The advent of catalysts (re)generation from the oxidized transition metal/ligand catalysts allows for the use of ppm level of catalysts in an ATRP, and offers more environmentally benign and industrially favorable reaction conditions for the synthesis of polymers. This work mainly explores electrochemically controlled atom transfer radical polymerization (eATRP) with diminished catalysts conditions as one of many catalysts regeneration ATRP systems being examined in the past decade. This dissertation is composed of nine chapters. Chapter I reviews recent progress in electrochemically controlled chemical reaction and polymerization. Chapter II provides an in-depth study of eATRP and serves as a basis for the discussions in Chapter III on developing a simplified eATRP reaction (seATRP). Chapters II and III cover six appendices, which include related collaborations, explanations on catalysts development and characterization, polymerization mechanism, and evaluation of new polymerization procedures. Chapter IV and V address related aqueous eATRP techniques. Chapter IV details optimization of polymerization conditions for acrylamides and minimization of side reactions. Chapter V explores miniemulsion polymerization of n-butyl acrylate which requires optimization of aqueous-organic phase catalyst communication. Chapter VI addresses development of electrochemically mediated reversible addition-fragmentation chain transfer (eRAFT) polymerization of methyl methacrylate. Chapters VII to IX discuss the synthesis of copolymers with complex polymeric architectures, i.e., star polymers. Specifically in Chapter VII procedures for achieving high yield for the synthesis of stars by combining arm-first methods and eATRP to reduce initial intermolecular termination reactions. Chapter VII also contains an appendix on star synthesis by the core-first method via eATRP. Chapter VIII and IX elucidate applications of the functional star polymers. In Chapter VIII, the preparation and application of light induced crosslinkable star polymers in surface patterning are discussed and extended to biomedical applications. Lastly, Chapter IX encompasses temperature responsive surfaces, that were prepared by star polymers upon UV irradiation, as smart cell cultivate substrates.