In-situ crosslinking of 1,4-butanediol diglycidyl ether for preventing crack disease of traditional Chinese scroll paintings

The crack disease is one of the main diseases in traditional Chinese scroll paintings. Using gelatin alum aqueous solution (GAW) and paper strips in the traditional restoration is the main reason for the rapid recurrence of crack disease. In this work, a new method was proposed for preventing crack disease based on in-situ crosslinking of 1,4-butanediol diglycidyl ether (BDDE). Trace amounts of BDDE (0.04 wt%) was used for softening and toughening aged paper-based painting core, making its flexibility close to that of new lining paper, which facilitated the mounting without GAW. Meanwhile, BDDE cross-linked cellulose nanofiber was used for cracks reinforcement instead of paper strips. The evaluated results indicated that the simulated mountings processed with this new method exhibited higher folding endurance and smaller stiffness compared with traditional restoration, achieving uniform and high flexibility. After 30 days of aging, the repaired mountings still showed better flexibility and smaller chromatic aberration, indicating outstanding aging resistance. The improvement in flexibility of aged Xuan paper was attributed to the in-situ crosslinking of BDDE in paper fibers and formed polar hydroxyl groups. The outstanding durability was owing to the good anti-aging performance and water retention, and weak alkalinity of treated paper with BDDE, preventing rapid brittleness and acidification. Therefore, this work will provide an important reference for preventing crack disease of traditional Chinese scroll paintings.