Controlled Polymerization of Norbornene Cycloparaphenylenes Expands Carbon Nanomaterials Design Space
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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
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Nitroarene Photoactivation Promotes Oxidative Deconstruction of Olefinic Polymers
Photoactivation of nitroarenes has been recently reported to induce the transformation of alkenyl bonds into carbonyl functionalities. Capitalizing on this unique photochemical mechanism, this study explores the use of nitroarenes to achieve oxidative cleavage of olefinic polymers under visible light irradiation. The degradation of various olefinic polymers, including commercially available polybutadiene, polynorbornene, both linear and cyclic poly(phenylacetylene), as well as backbone-modified polyacrylates with alkenyl functionality was investigated. To elucidate the efficacy of this methodology, a series of nitroarene derivatives bearing variable substituents were screened for their degradative efficiency on polybutadiene. Varying nitroarene stoichiometry, reaction temperature, and pos-treaction workup conditions were investigated to optimize degradation conditions. Furthermore, the results demonstrated that photoexcited nitroarenes enable efficient oxidative degradation of olefinic polymers in a safe and sustainable manner, providing a novel strategy for mild macromolecular deconstruction.
Bond cleavage↗
Backbone Engineering of Monodisperse Conjugated Polymers via Integrated Iterative Binomial Synthesis
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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
Molecular weight distribution of raw and catalytic fast pyrolysis oils: comparison of analytical methodologies
Comprehensive analysis of the molecular weight distribution of raw and catalytic fast pyrolysis oils remains a key technical hurdle to understanding oil quality and multiple methods may be necessary to accurately represent all components present.
09 BIOMASS FUELS↗
Characterization of polymer properties and identification of additives in commercially available research plastics
This work reports the analysis of 59 commercially available polymers from 20 different polymer classes for thermal properties, macrostructure, molecular mass distribution, and inorganic and organic additives, highlighting the need to characterize research polymers prior to recycling studies.
36 MATERIALS SCIENCE↗