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Abstract Non‐biodegradable petroleum‐based plastic wastes have become a leading environmental concern, and new efforts are underway to prepare biobased and biodegradable replacements. We have explored the preparation of adhesives suitable for use in consumer products, and here we report the development of waterborne, biodegradable adhesives from biobased monomers resulting in adhesives exceeding 70% biocontent. Using water as the polymer medium, viscosity challenges and the use of volatile organic solvents are avoided. Material properties of the polyurethane dispersions, resulting films, and laminates produced showed M_wranging between 56,000 and 124,000. Lastly, the biodegradability of films and laminates was evaluated. The resulting metrics indicate that the adhesives produced meet the desired mechanical and biodegradability targets, indicating that high renewability content solvent‐free polyurethane dispersions are a viable solution for lamination adhesives. 

Abstract. Ice-nucleating particles (INPs) represent a rare subset of aerosol particlesthat initiate cloud droplet freezing at temperatures above the homogenousfreezing point of water (−38 ∘C). Considering that the oceancovers 71 % of the Earth's surface and represents a large potential sourceof INPs, it is imperative that the identities, properties and relativeemissions of ocean INPs become better understood. However, the specificunderlying drivers of marine INP emissions remain largely unknown due tolimited observations and the challenges associated with isolating rare INPs. Bygenerating isolated nascent sea spray aerosol (SSA) over a range ofbiological conditions, mesocosm studies have shown that marine microbes cancontribute to INPs. Here, we identify 14 (30 %) cultivable halotolerantice-nucleating microbes and fungi among 47 total isolates recovered fromprecipitation and aerosol samples collected in coastal air in southernCalifornia. Ice-nucleating (IN) isolates collected in coastal air were nucleated ice fromextremely warm to moderate freezing temperatures (−2.3 to −18 ∘C). While some Gammaproteobacteria and fungi are known to nucleate ice attemperatures as high as −2 ∘C, Brevibacterium sp. is the first Actinobacteriafound to be capable of ice nucleation at a relatively high freezingtemperature (−2.3 ∘C). Air mass trajectory analysis demonstratesthat marine aerosol sources were dominant during all sampling periods, andphylogenetic analysis indicates that at least 2 of the 14 IN isolates areclosely related to marine taxa. Moreover, results from cell-washingexperiments demonstrate that most IN isolates maintained freezing activityin the absence of nutrients and cell growth media. This study supportsprevious studies that implicated microbes as a potential source of marineINPs, and it additionally demonstrates links between precipitation, marineaerosol and IN microbes.