Effect of cellulose micro/nanofibrils and carboxylated styrene butadiene rubber coating on sack kraft paper

The main objective of this research is to evaluate the influence of coating based on cellulose micro/nanofibrils (CMF) and carboxylated styrene butadiene rubber (XSBR) on sack kraft paper, for possible use in packaging. Filmogenic solutions were applied manually as a coating on sack kraft paper. These solutions were prepared by suspensions of CMF 1.5 % w/v with the addition of different content of XSBR (0, 2, 10, and 20 % about the total mass of CMF). Uncoated sack kraft paper was used as control. Films were obtained by casting and characterized physically, morphologically, and mechanically. The results demonstrated that XSBR and CMF composite suspension showed good performance as a coating on sack kraft paper. The formation of homogeneous structures well distributed on paper can be observed on scanning electron microscope images. Coatings containing XSBR presented a smoother surface, less porosity and hydrophilicity, and a greater coalescence, with good properties of air resistance and water vapor permeability. However, regarding mechanical properties, there were no improvements in coated papers. Therefore, the present study contributed information on the development of more flexible and hydrophobic cellulosic papers for possible applications in the industrial packaging sector.