title: Synthesis of Alkaline-Soluble Cellulose Methyl Carbamate Using a Reactive Deep Eutectic Solvent.
abstract: This study presents the use of a reactive deep eutectic solvent (DES) for the chemical modification of wood cellulose fibers. DES based on dimethylurea and ZnCl2was used to synthetize cellulose methyl carbamate (CMeC). This synthesis was performed at elevated temperature under solvent-free conditions. Chemical characterization based on FTIR and NMR indicated that methyl carbamate was successfully introduced to cellulose, and a degree of substitution (DS) of 0.17 was obtained after 3 h of reaction at 150 °C. The product with a DS of 0.17 exhibited good alkaline solubility (in 3 % NaOH solution) after freeze-thawing, whereas the original cellulose fibers were practically insoluble even in 9 % NaOH. As dimethylurea can be produced from CO2, this method can be used as a sustainable way to obtain novel cellulose materials with desirable properties for use in a wide range of applications.
authors.affiliation: Fibre and Particle Engineering Research Unit, University of Oulu, P.O. Box 4300, FI-90014, Finland.
authors.forename: Juho Antti
authors.identifier: 0000-0002-7404-3340
authors.initials: JA
authors.lastname: Sirviö
authors.affiliation: Research Unit of Sustainable Chemistry, University of Oulu, P.O. Box 3000, FI-90014, Finland.
authors.forename: Juha P
authors.initials: JP
authors.lastname: Heiskanen
mesh_terms: D002219:Carbamates / Q000138:chemical synthesis* / Q000737:chemistry*; D002482:Cellulose / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry; D060326:Chemistry Techniques, Synthetic; D006863:Hydrogen-Ion Concentration; D012972:Sodium Hydroxide / Q000737:chemistry; D012995:Solubility; D012997:Solvents / Q000737:chemistry*
chemical_list: D002219:Carbamates; D012997:Solvents; D012972:Sodium Hydroxide; D002482:Cellulose
keywords: biomass; cellulose; deep eutectic solvent; green chemistry; methyl carbamate