Moderate surface acetylation of nanofibrillated cellulose for the improvement of paper strength and barrier properties

This study evaluated the effect of using acetylated nanofibrillated cellulose (ANFC) and acetylated pulp (AP) fibers to modify strength and barrier properties of paper. Nanofibrillated cellulose (NFC) was produced using an ultra-fine friction grinder. The NFC and pulp fibers were modified by the heterogeneous acetylation process. Chemical modification was characterized by Fourier transform infrared spectroscopy together with titration. The values of density, burst strength, tensile strength, and air resistance were increased by adding NFC and ANFC to the paper combination. Addition of NFC to the non-acetylated pulp had no significant effect on the water absorption of made paper (p > 0.05), while addition of ANFC to the non-acetylated pulp led to a decrease in the water absorption of about 23.1%. The results indicated that addition of partially acetylated NFC to the pulp caused an improvement in both the air and water barrier and mechanical strength properties of the paper, simultaneously.