Study On The Protection Of Stone Cultural Relics By TiO₂ Modified Sol

Stone cultural relics are of great significance to the study of history,religion,art and other aspects.However,most of them are exposed outdoors,which are affected by multiple damage factors of the external environment for a long time,resulting in the destruction of stone cultural relics such as pulverization.In order to adapt to the new requirements for protection materials of stone cultural relics,this work combines the performance characteristics and advantages of TiO₂ sol and TiO₂ nanoparticles,proposes to disperse TiO₂ nanoparticles into TiO₂ sol,prepares a series of new TiO₂ nano modified sol materials,and evaluates the protection performance of stone cultural relics.The specific content includes the following three parts:Part I:Preparation and protective properties of ordinary TiO₂ nanoparticle modified sol materials.Through the sol-gel method,the stable,transparent TiO₂ sol solution is prepared.The ordinary TiO₂ nanoparticles are dispersed in the TiO₂ sol solution.The optimal ratio of particles to sol is 0.05 g /100 m L,and the number of coating layers is 4.The common stone relic substrates: sandstone and marble are the test objects.Evaluation of protection performance.The good protective properties of TiO₂ nanoparticle modified sol materials include:（1）It is super-hydrophilic,which is conducive to dust removal;（2）It has good air permeability and does not affect the "breathing" effect of stone;（3）It makes stone reduced water absorption and resistance to water damage;（4）significant improvements in acid resistance and weather resistance,and the cycle number of weather resistance experiment is 4 times that that of silicone material.Part II:Preparation and protective properties of rod-shaped TiO₂ nanoparticles modified sol materials.The rod-shaped TiO₂ nanoparticles were synthesized by hydrothermal method,and the performance of rod-shaped TiO₂ nanoparticles modified sol material was evaluated by the best ratio of particles and sol in the first part,experimental objects and methods.The results show that:（1）the addition of rod-shaped TiO₂ nanoparticles makes the stone surface more compact and flat,and the stone gets lower water absorption;（2）the acid resistance is stronger than that of the first part of the material;（3）the acid resistance and weather resistance are better than that of the pure TiO₂ sol;（4）the dye degradation rate is the fastest,which is 12 times that of pure TiO₂ sol material,and the photocatalytic performance is the best.Part III:Study on preparation and protection properties of microspheres and nano flower-shaped TiO₂ particles modified sol materials.Nano flower and micro spherical TiO₂ particles were prepared by hydrothermal method and microwave method respectively.The preparation method and performance test of modified sol are consistent with the second part.The size of TiO₂ particles affects the modification,and the larger the particles is not conducive to the load;in terms of water erosion resistance,acid resistance and weather resistance,the nano flower shaped TiO₂ nanoparticles modified sol material is the best;but the photocatalytic performance: micro spherical TiO₂ modified sol material > pure TiO₂ sol material modified sol material > nano flower shaped TiO₂ particles modified sol material,indicating that the crystal shape of TiO₂ nanoparticles affects the modification The anatase phase is more than rutile phase.In summary,through the research of this topic,TiO₂ modified sol materials can effectively protect the stone cultural relics,which is of great significance to promote the research of TiO₂ materials in the field of stone cultural relics protection,and compare the above four types of modification.The performance of the sol material,the rod-shaped TiO₂ nanoparticle modified sol material has the best overall protection performance,and can be used as the first choice of protection material;the nano-flower-shaped TiO₂ modified sol material is followed;the protection performance of the microsphere and ordinary TiO₂ nanoparticle modified sol is similar.