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Biomass-derived isosorbide (IS) was converted into a mono-glycal ( i.e. vinyl ether) derivative (Gly-IS) to investigate its efficacy for cationic polymerization. While homopolymerization was unsuccessful, likely due to the steric demand near the propagating cationic site, copolymerization with isobutyl vinyl ether (IBVE) revealed great promise for the use of Gly-IS as a rigid and sustainable comonomer. Traditional cationic methods yielded copolymers with IBVE, but the incorporation of Gly-IS was hindered by the propensity for Lewis acids to catalyze a ring-opening reaction driven by aromatization to a chiral furan analog. This reaction was discovered to be significantly sequestered through the use of metal-free photoinitiated cationic copolymerization methods that are void of Lewis acid reagents, yielding a much higher incorporation of Gly-IS (up to 42 mol%) into the copolymer. The rigidity and chirality of the Gly-IS repeating unit was found to increase the glass transition temperature ( T g ) up to 25 °C with 33 mol% incorporation at modest molar mass (10.4 kg mol −1 ) while all copolymers displayed thermal stability up to 320 °C under inert atmosphere. Due to its chiral structure, specific optical rotation [α] of the copolymer also increased with incorporation of Gly-IS. Therefore, Gly-IS presents opportunity as a sustainable and value-added comonomer to modulate the properties of common poly(vinyl ether) systems. 

Rainwater and gas phase ethanol concentrations increased approximately fourfold between 2010 and 2017 in Wilmington, NC, USA. This 8-year study demonstrates that the gas phase and rainwater concentrations of ethanol have risen due to increased production and use of ethanol as a biofuel. Rainwater ethanol concentrations are close to equilibrium with local atmospheric gas phase concentrations and have increased in proportion to increased air concentrations. Ethanol emissions are important because they impact the oxidizing capacity of the atmosphere due to the reactivity of the alcohol towards hydroxyl radical. Gas phase ethanol contributes to air pollution through oxidation to acetaldehyde, with subsequent production of ozone, and in high NO_xregions production of peroxyacetyl nitrate (PAN). However, combustion of ethanol can also lower emissions of acetaldehyde precursors such as alkenes, suggesting that the potential impact of ethanol combustion is complex. The large increase in the concentration of ethanol in both the gas and condensed phases indicates that existing sinks are not sufficient to remove the excess alcohol being added to the atmosphere from biofuel use. This suggests that the projected growth of ethanol as a biofuel will result in considerable increases in atmospheric concentrations within the next few years with direct ramifications on a host of fundamentally important atmospheric processes.