Date of Award

Summer 6-2016

Embargo Period

9-5-2017

Degree Type

Dissertation

Degree Name

Doctor of Philosophy (PhD)

Department

Chemistry

Advisor(s)

Krzysztof Matyjaszewski

Abstract

work explores the application of Atom Transfer Radical Polymerization (ATRP) to improve various aspects of synthesizing well-defined porous polymer-based materials. The thesis specifically focuses on two particular classes on materials; mesoporous nitrogen-doped nanostructured carbons (N-doped nanocarbons) and polymerized high internal phase emulsions (polyHIPEs). The introductory chapter discusses, in great detail, reversible deactivation radical polymerization (RDRP) methods, including ATRP, that can be used to synthesize polyacrylonitrile-based precursors for the preparation N-doped nanocarbons and discusses their potential applications. The introduction chapter also details the requirements for formation of HIPEs and polyHIPEs, with a focus on the various hurdles that must be overcome for polyHIPEs to become commercially viable and widely applicable materials. Chapter 2 focuses on the synthesis of PAN-containing block copolymer (BCP) precursors by initiators for continuous activator regeneration (ICAR) and metal free (MF) ATRP, which allow for a significant reduction in the concentration of Cu-catalyst required for synthesis of well-defined BCPs; to 1 ppm in ICAR ATRP or no metal catalyst in MF ATRP. Chapter 3 discusses the synthesis of a range of PAN-based stars and characterization of carbon materials derived from these precursors. Chapter 4 discusses the synthesis and use of tetrazine cross-linked SiO2-g-Poly(4-cyanostyrene) as precursor for nitrogen-doped nanocarbons. The application of ATRP to prepare materials for use in HIPE systems and synthesize polyHIPEs was investigated in Chapter 5, where optimized conditions for activators generated by electron transfer (AGET) ATRP were developed to synthesize fully degradable polyHIPEs from commercially available monomers and cross-linker. Chapter 6 details the synthesis poly(ethylene oxide) and poly(n-butyl acrylate) mikto-arm stars that preferentially formed water in oil HIPEs and were able to stabilize water-in-xylene emulsions with star loading (vs. total emulsion) down to 0.005 wt% and water-in-styrene HIPEs down to 0.04 wt%. In a final step towards preparing a surfactant free stable polyHIPEs these mikto-arm stars were functionalized with reactive alkyl halide or vinyl moieties, so they could be incorporated into the polyHIPE network, as well as stabilize the HIPE, which is discussed in Chapter 7.

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