A continuous and scalable method for the wet spinning of cellulose nanofibrils (CNFs) is introduced in a core/shell configuration. Control on the interfacial interactions was possible by the choice of the shell material and coagulant, as demonstrated here with guar gum (GG) and cellulose acetate (CA). Upon coagulation in acetone, ethanol, or water, GG and CA formed supporting polymer shells that interacted to different degrees with the CNF core.
View Article and Find Full Text PDFThe conventional vulcanization process applied to elastomers is irreversible and hinders therefore their useful recycling. We demonstrate here that natural rubber can be reversibly crosslinked via the Diels-Alder coupling of furan and maleimide moieties. The furan-modified natural rubber used in this strategy was also exploited to bind it to maleimide-modified nanocellulose, thus generating a covalently crosslinked composite of these two renewable polymers.
View Article and Find Full Text PDFThis work describes a very simple, rapid, and efficient approach to the hydrophobization and lipophobization of cellulose fibers through their reaction with gaseous trichloromethylsilane (TCMS). The characterization of the modified surface involved FTIR-ATR and solid-state (29)Si NMR spectroscopy, scanning electron microscopy (SEM), and contact angle measurements with different liquids. The modification generated an inorganic coating around the fibers, associated with the construction of a three-dimensional network of Si-O-Si bridges partly bound to the polysaccharide macromolecules.
View Article and Find Full Text PDF