The effect of addition of lignocellulose nanofiber produced from old corrugated container pulp on recycled paperboard properties

In recent years, plenty of studies have focused on the application of cellulose nanofiber to improve the mechanical and physical properties of paper. But, in this research, the effect of lignocellulose nanofibers produced from recycled old corrugated container as raw material using ultra-fine grinder, on some mechanical properties and production process parameters of paperboard was investigated. TEM images of produced nanofibers indicated that the nanofiber width was in the range of 10-80 nm. Then, various dosages of nanofiber were applied by bulk addition method to the furnish. Eventually, the evaluation of tensile strength revealed that the application of 5% lignocellulose nanofiber caused more than 50% increase in tensile strength of produced paperboard. Although, the bulk addition of high dosages of the nanofiber resulted in reduction of bending index (bending stiffness), tear index and especially freeness of the furnish.