Fire-resistant and antibacterial Chinese Xuan paper by fully bio-based chitosan/phytic acid coating on pulp fibers

Xuan paper is outstanding representative of the precious Chinese handmade papers which is popular with traditional calligraphy and painting. However, the highly flammability of Xuan paper results in the latent fire risk. In this research, fire-resistant and antibacterial Chinese Xuan papers were prepared by fully bio-based chitosan (CS)/phytic acid (PA) intumescent flame retardant system. Xuan paper achieved the excellent flame retardancy with limit oxygen index value of 36.4% when it was coated with 20 BL CS/PA on pulp fibers . The vertical flame properties and cone calorimetry test of Xuan papers also revealed their flame retardancy were greatly improved. The tensile strength of Xuna paper was slightly influenced by CS/PA coating. The CS/PA coating on Xuan papers could greatly enhance their antibacterial properties . The flame retardant mechanism of coated Xuan papers was investigated. The results showed the CS/PA coating on pulp fibers could act through intumescent flame retardant action. The ink wetting property of Xuan paper won’t be influenced by CS/PA coating on the pulp fibers. This research provides research basis for fire-resistant and antibacterial Xuan papers by using the fully bio-based chitosan/phytic acid coating on pulp fibers. • Fire-resistant and antibacterial Xuan paper was prepared by fully bio-based coating. • Xuan paper achieved a LOI value of 36.4% when it was coated by 20 BLs CS/PA. • CS/PA coating on pulp fibers greatly enhance the antibacterial property of Xuan paper.