Technical field:
The invention relates to the preparation of water-absorbing materials, the special use of the water-absorbing materials and the special materials used for the special use. The water-absorbing material of the invention is water-absorbing resin, and the special use of the water-absorbing material of the invention refers to the restoration and protection of cultural relics made of water-absorbing materials.
Background art:
The appearance of super absorbent resin began in 196 1 year. American C.R.Russdl and others began to study the grafting of acrylonitrile on starch, and then GF. Fanta and others continued to study it. Water-absorbent resin was first industrialized in Henkel Company. Since then, countries all over the world have done a lot of research on the types, properties, manufacturing methods and application fields of super absorbent, among which the United States and Japan have the greatest research results. Super absorbent resin is a widely used and relatively mature material, which is widely used in medicine, health, agriculture, forestry, food and other fields. Super absorbent can absorb hundreds or even thousands of times its own weight, but its salt tolerance is poor, and the rate of absorbing physiological saline is often only one tenth of that of absorbing distilled water. In recent years, salt-tolerant superabsorbent resin has become a hot spot in the research of superabsorbent resin.
Please refer to the following document 1 Zou Xinxi for the existing preparation methods of super absorbent materials. Super absorbent [M]. Second edition. Chemical Industry Press 2002 2 CoCo Lee, Wang Li, Jiang Ailing. Research progress of salt-tolerant super absorbent resin [J]. Guangdong Chemical Industry, 2006,33 (3): 59,68-70.
3 Li Yunyan. Study on Preparation of Super Absorbent Resin by Grafting Acrylic Acid onto Starch [J]. Fine Petrochemical Industry, No.6, 2004, pp. 50-53
4 Li Yali. Synthesis of electrolyte-resistant super absorbent resin and its liquid absorption performance [J]. Applied Chemical Engineering, 2003,32,4: 27-295 Qi Xiaohua, et al. Preparation and properties of diatomite composite super absorbent resin [j]. Polymer for advanced technology, 2007,18:184
China patent 98 122254.4 and China patent 2004100141.5 also disclose the preparation methods of water-absorbent resins.
The existing super absorbent resin often has low salt tolerance, the existing super absorbent material absorbs water too slowly, or the water absorbent material itself contains strong acid or strong base groups, which greatly affects the application range of this material.
Cultural relics protection is a basic work in this field. Due to the long-term influence of the unearthed and preserved environment, cultural relics are generally damaged or destroyed to some extent. The purpose of cultural relics protection is to reduce the damage of cultural relics and prolong their life. Salt damage is a phenomenon that harms the protection of cultural relics. Usually, salt crystallizes inside an object and destroys its structure. Salt damage is widespread in the field of cultural relics protection. And once salt damage happens, the damage is often irreversible. Therefore, it is necessary and urgent to downplay the protection of cultural relics.
Adsorption desalination is a commonly used desalination method in the field of cultural relics protection, which is generally suitable for desalination of stone tools and murals. At present, some desalting materials include common absorbent paper, pulp, absorbent cotton, gauze, expansive soil and so on. When using these materials as adsorption materials, distilled water should be carefully injected into the micropores of the salt-damaged parts of cultural relics to dissolve the soluble salt. After dissolving for a certain period of time, apply the above absorption material to the water injection site. Through the adsorption of adsorption materials, the salt in cultural relics is brought out in the form of salt solution and enriched on the adsorption materials. Due to the limitation of the material itself, the efficiency of adsorption desalination is low, and the desalination process often needs to be repeated many times, even more than ten times. Therefore, it is an urgent problem in this field to find a material with excellent adsorption performance without damaging cultural relics.