Reinforcing and protecting leather-based relics using gelatin/tannic acid composites.

Subject to environmental influences such as temperature, humidity, light, and microorganisms, leather-based relics are easily be deteriorated, which will damage their historical value. In this work, gelatin/tannic acid composites (Gel/TA) was prepared and characterized to investigate their potential as a novel approach for reinforcing and protecting leather-based relics. According to the characterization, it was found that hydrogen bonds was formed between gelatin and TA, and Gel/TA presented increases in the antioxidant capacity(82.12 %), compared to the gelatin. After reinforcing the aged leather with Gel/TA, the cross-linking between leather collagen fibers is more closely interconnected. The mechanical properties and antibacterial activity of leather-based relics are significantly improved. The oxidation resistance of leather-based relics increased from 20.72 % to 63.03 %. Under the condition of accelerated simulated aging, the time to reduce the mechanical properties of reinforced leather by 50 % was extended from 7.6 days to 10 days. At the same time, the color of leather-based relics changed slightly. This result suggested that the Gel/TA composites play an important role in the filling and reinforcement protection of leather artifacts. This work will put forward a feasible way to producing sustainable multifunctional materials for leather-based relics.