HYDROPHOBIC NANOCELLULOSE-COATED PAPER AND PAPERBOARD

In some variations， the present invention provides an oil-resistant paperboard material coated with hydrophobic nanocellulose. The paperboard material is free of a fluorocarbon coating. In other variations， an oil-resistant paper is coated with hydrophobic nanocellulose and is free of a fluorocarbon coating. The hydrophobic nanocellulose may include lignin-coated cellulose nanofibrils， lignin-coated cellulose nanocrystals， or a combination thereof. A process for producing these materials is also provided， comprising: fractionating a lignocellulosic biomass feedstock in the presence of an acid， a solvent for lignin， and water， to generate cellulose-rich solids and a liquid containing hemicellulose and lignin， wherein a portion of the lignin deposits onto a surface of the cellulose-rich solids， thereby rendering the cellulose-rich solids at least partially hydrophobic; mechanically treating the cellulose-rich solids to form hydrophobic nanocellulose; and coating a paper or paperboard material with the hydrophobic nanocellulose， to generate an oil-resistant paper or paperboard material.