A kind of organic gel for removing polyacrylic resin on mural surface based on nano calcium hydroxide and preparation method thereof

Abstract

The invention relates to an organogel for removing polyacrylic resin on the surface of murals based on nano-calcium hydroxide and a preparation method thereof. Nano-calcium hydroxide and epoxy resin are added into an ethyl acetate solution and stirred for 12-24 hours to form a polyacrylic resin. Acrylic cleaning gel. The preparation method is extremely simple, saves time, does not require heating and has low cost. In the preparation process, nano-calcium hydroxide reacts with ethyl acetate to generate calcium acetate as a cross-linking agent to promote gel formation. Calcium acetate is not only non-toxic, but also a food preservative, which greatly improves the safety of the gel. The experiment of removing polyacrylic resin polymer on the surface of mural shows that the removal rate can reach more than 95%. In addition, according to the amount of polyacrylic resin on the surface of the mural, the percentage of ethyl acetate can be flexibly adjusted from 70%-85% to obtain the best cleaning effect. The gel has excellent industrial production prospects, and can be extended to the cleaning of high molecular polymers on the surfaces of other cultural relics such as stone and paper cultural relics.

Description

technical field [0001] The invention belongs to the technical field of ancient mural protection materials, and relates to an organic gel for removing polyacrylic resin on the surface of murals based on nano-calcium hydroxide and a preparation method thereof. Background technique [0002] Polyacrylic resin is an organic polymer protective material for murals widely used at home and abroad. The material has many advantages such as strong adhesion, simple construction, and little effect on the color of murals (Central Plains Artifacts, 2004, 01, 81-86), and has been shown in the restoration and protection of murals in Dunhuang in my country, India, Italy and other countries. good effect. However, the material is prone to aging, yellowing, and brittleness, resulting in mechanical degradation or even failure; secondary reinforcement is required after a long period of time, and the aged material will have a great negative impact on secondary reinforcement, so it needs to be remove...

AI Technical Summary

Problems solved by technology

[0003] At present, there are several methods of removal: (1) use a cotton swab dipped in ethyl acetate to wipe, this method is extremely inefficient and ineffective, and must be careful so as not to affect the mural; (2) use microemulsion, microemulsion The emulsion contains a cleaning agent such as ethyl acetate. Experiments have proved that the microemulsion has an excellent cleaning effect on polyacrylic resin and high efficiency. However, this system contains a large amount of water and surfactants, which are very easy to cause damage to murals (Adv.Colloid. Interface Sci.2014, 205, 361-371); (3) organogel, the preparation principle is to use cross-linking agent to connect polymers to form a network structure, and coat the cleaning agent in the network while the gel is formed. Gel preparation does not use water and surfactant, good cleaning effect, high removal rate (more than 80%), but the preparation is very complicated, time-consuming, both inert gas and heating are required, and the preparation process also needs repeated cleaning (each It takes 24 hours for the first cleaning), and it takes at least 4-5 days to successfully prepare the cleaning gel. In addition, the cleaning agent content in the gel can only be calculated by the final gel product and cannot be adjusted in advance. More importantly, the preparation of the gel The cross-linking agent used in the glue is highly toxic (Appl. Phys. A2015, 121, 857-868)