Preparation and application of modified carboxymethyl cellulose Si/polyacrylate protective coating material for paper relics

There are large numbers of paper cultural relics in China, the country where paper making was invented. However, the paper relics have not been adequately protected so they are at risk of ageing, damage and disappearance. In order to better protect the paper relics, modified carboxymethyl cellulose/Si/polyacrylate protective materials were prepared with acrylicresin and modified carboxymethyl cellulose which has a good affinity with the paper and modified silica, improving the mechanical strength and ability to withstand weathering. The modified CMC/Si/polyacrylate protective material was analysed using infrared spectroscopy, transmission electron microscopy, differential scanning calorimetry and other performance-testing devices. The surface morphology of the paper samples was analysed using scanning electron microscopy. The protective material so prepared was evaluated by subjection to accelerated ageing (dry heat treatment). The results showed the protective material films to have good hydrophobicity, acid/alkali resistance and mechanical strength. When the content of SiO₂ is 6 mass %, the protective material has an excellent comprehensive performance. The results of the ageing test reveal that the prepared material can effectively slow down the ageing rate. The prepared material is suited to the protection of paper cultural relics.