Novel antibacterial paper based on quaternized carboxymethyl chitosan/organic montmorillonite/Ag NP nanocomposites

An environmentally friendly antibacterial agent, namely, Ag NP-loaded quaternized carboxymethyl chitosan/organic montmorillonite (QAOM) nanocomposite, was prepared. The novel QAOM nanocomposite was obtained through an environmentally friendly process by using quaternized carboxymethyl chitosan (QCMC) and organic montmorillonite (OMMT) as reducing and stabilizing agent for Ag NP synthesis. Finished papers with QAOM nanocomposites were prepared by performing surface coating and internal additive methods. Physical properties and antimicrobial activity of the finished paper were investigated. The results revealed that Ag NP remained spherical in dry QAOM nanocomposites with uniform size and good dispersion, and the exfoliated montmorillonite layers were evenly distributed in the QCMC matrix. The presence of QAOM nanocomposites positively affected the tensile, tear, and bursting strengths of the finished paper. The paper prepared by using surface coating performed better than that produced by using the internal additive method. Moreover, the finished paper with QAOM nanocomposites showed an excellent antimicrobial capacity, and the antibacterial capacity of paper produced by using surface coating was stronger than that produced by using internal additive method. Therefore, this study provides basic data for an efficient and safe antibacterial agent that can be applied in the paper industry. (C) 2013 Elsevier B.V. All rights reserved.