Twin-roll forming, a novel method for producing high-consistency microfibrillated cellulosic films

Micro-nano fibrillated cellulose (MNFC) films have the potential for applications in, e.g., packaging and printed electronics. However, the production paradigm for these types of products has still not been established. This study uses twin-rollers to form films from high consistency (15% w/w) micro fibrillated cellulose furnishes. MFC furnishes were produced at 20% wt dry matter content with enzymatic hydrolysis and PFI refining. We used the twin-roller method to spread the material over a supporting substrate by repeatedly passing between two parallel rollers with decreasing nip. Rheological behavior and physical properties of furnishes were analyzed. We found that only some furnishes with relatively short fiber lengths were formable. Refining improved the formation of the sheets. Roll-formed sheets showed comparable strength and formation to conventional wet-laid hand sheets.