Research on Deacidification and Reinforcement of Archives Paper with Calcium Carbonate Nanoparticles/Modified Hydroxypropyl Cellulose

The aging process of paper will be accelerated by acidification behavior during the storage process of paper archives, and the mechanical properties of paper archives will be weakened. By deacidizing and strengthening, the further aging of the acidified archives paper can be delayed or prevented, and the mechanical properties can be improved, so that the service life of paper archives is prolonged. To delay even to prevent the aging process, deacidizing and strengthening technology is employed. Herein, the "hybrid" system was reported by combining nano-calcium carbonate as deacidification agent, modified hydroxypropyl cellulose as reinforcement agent and ethanol as dispersant. The artificially acidified paper was brushed with it, and the pH value, mechanical properties and whiteness were measured to study the effect of deacidification and reinforcement. The results showed that oleic acid was successfully grafted onto hydroxypropyl cellulose by N,N '-carbonyl diimidazole mediated method to obtain oleic acid grafted hydroxypropyl cellulose with good dispersion in ethanol. After treating acidified paper with "hybrid" system, the pH value and the tensile strength index increase, the whiteness is almost unchanged, that is, the use of "hybrid" system plays a good deacidifying strengthening effect. The acidified paper samples before and after treatment with "hybrid" system were subjected to dry-heat aging treatment. Compared with acidified paper, the pH value, tensile strength index and whiteness of acidified paper treated with "hybrid" system are effectively inhibited, that is, the use of "hybrid" system can effectively delay the aging and acidification process of paper.