N₂O deconstruction of polycyclooctene to generate carbonyl-functionalized macromonomers

Deconstruction of polyolefins into functionalized macromonomers presents a compelling strategy for polyolefin upcycling by creating macromonomers through dehydrogenation/depolymerization. We show that nitrous oxide (N₂O), a greenhouse gas waste product from the production of nylon, mediates the deconstruction of polycyclooctene (PCOE) and generates carbonyl-functionalized macromonomers. Carbonyl incorporation and macromonomer molar mass were well controlled by reaction time, and subsequent hydrogenation readily removed residual carbon-carbon double bonds. Here, we also demonstrated that the reaction could progress efficiently with substrates of moderate levels of unsaturation, closely mimicking partially dehydrogenated polyethylene. Such carbonyl-functionalized macromonomers could serve as feedstock for preparing vitrimers and other functional polymers.. Authors: Ogbu, Ikechukwu Martin [University of Pennsylvania, Philadelphia, PA (United States)] (ORCID:0000000290537519); Tu, Chien-Hua [University of Pennsylvania, Philadelphia, PA (United States)]; Fastow, Eli [University of Pennsylvania, Philadelphia, PA (United States)] (ORCID:0000000326742056); Hinton, Zachary R. [University of Delaware, Newark, DE (United States)]; Winey, Karen I. [University of Pennsylvania, Philadelphia, PA (United States)] (ORCID:0000000158563410). DOE Contract: SC0022238. Subjects: 36 MATERIALS SCIENCE; 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Polyolefins; deconstruction; ketone-functionalized; macromonomers; polycyclooctene