The Study On Earthen Culture Heritages Conservation Material And Its Anti-weathering Mechanism

The studied subject is ancient Gaochang City Relics, one of heritages listed in the protection coverage of the Nation Cultural Relic Bureau. First part of this paper is a detailed overview of relevant fields from characteristics of porous earth relics in arid northwest region of China, existing weathering situation, dominant influence factors, to deterioration characteristics of the cultural object, as well as evaluation methods.The problems and shortage of previous reinforce and protection materials used for porous relics were understood on the basis of completely overview to their structure characteristics and property. On the other hand, the structure feature, special characteristics and the viability assessment in cultural relics of organic silixane-modified crylic-acid resin emulsion were proposed in this paper.Organic silixane-modified crylic-acid resin emulsion suited for the conservation purpose of cultural object was obtained with four kinds of acrylic acid ester and two kinds of organic silixane served as the main monomers separately. The selection of monomers composition, pH of the emulsion system, the amount of emulsifier and initiator, the temperature of copolymerizing system was chosen to discuss preparation process of batch method in the laboratory. The optimized conditions were as followings: 1) monomers compositions was MMA, BA, MA, AA for acrylic acid ester monomers and A-151, A-174 for organic silixane monomers; 2) copolymerizing system temperature was 70°C; 3) the pH range was 6.0-7.0; 4) the amount of emulsifier was 6% of total monomers weight; 5) the amount of initiator was 0.6% of total monomers weight. The final production was analyzed by FTIR and the results showed a good copolymer.The non-insitu investigation of a lot of properties about the testing sample of both strengthened and non-strengthened from the ancient Gaochang City has been carried out subsequently, such as the compressive strength, anti-wind-erosion performance, freezing-thawing cycles test, ultraviolet aging test, surface morphology (SEM), color changes as well as resistance to desegregation of water, chemical analyze, and so on. Desirable results were achieved in terms of many aspects, such as the water and wind erosion resistant ability, strengthen. Meanwhile, after strengthened, a well ventilated function that does not affect the breath of cultural object was tested, which can help to keep the cultural object long life. To summarize, the production is good enough to bear water decay, wind erosion and UV aging for a long time, and provided an excellent effect from the study of practical applications.