A levulinoyl ester-containing cellulose polymer is introduced as a waterborne coating. Incorporation of the biomass-derived levulinic acid proceeds via an unexpected intermediate and provides the unusual feature of a cellulose derivative that is readily chemically modified. The levulinoyl-cellulose ester could be chemically manipulated, allowing it to be dispersed to generate a waterborne hydrocolloid latex. This was capable of film-formation at room temperature, and was formulated for use as a coating of high-renewable content.

Cellulose is found to be a good source of waterborne film-forming materials when modified with the correct type and level of functional groups. The modification of cellulose to incorporate high levels of levulinic functionality and other C2–C6 alkyl esters is reported for the first time. The levulinyl-functionalized cellulose is readily modified to produce oxime or acylhydrazone derivatives, which is particularly useful to fine-tune the physical characteristics of the cellulose ester. This includes the glass transition temperature of the cellulose esters, their ability to produce fine uniform colloidal particles in aqueous media and ultimately provide the principle film-forming component of an architectural coating. The process has been demonstrated at the 500 g level suggesting ready scalability. Lewis acids and Lewis acid-assisted Brønsted acids are employed for the first time in such chemistry, and together with sulfur-based Brønsted acids are all found to be effective catalysts for the esterification of cellulose to produce mixed ester systems. The Lewis acid catalysts demonstrate exceptional activity and produce high molecular weight cellulose derivatives.

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Levulinyl cellulose esters have been produced as an effective renewable binder for architectural coatings. The title compound, C7H10O4 (systematic name: 2-methyl-5-oxo­tetra­hydro­furan-2-yl acetate), assigned as the esterifying species, was isolated and crystallized to confirm the structure. In the crystal, the mol­ecules pack in layers parallel to (102) utilizing weak C—H⋯O inter­actions.

Invited for this month′s cover is the Industrial Formulations group at the Ferrier Research Institute, Victoria University of Wellington. The image depicts plant matter being converted into a novel cellulose ester and, in turn, into a paint formulation suitable for architectural coatings. The Full Paper itself is available at