Research On The Compatibility Of The Same Kind Of Materials For The Repair Of The Cracked And Warped Decorative Layer Of Cultural Relics

At present,modern synthetic polymer materials are widely used for bonding and reposting of cultural relics.Although the bonding performance is good,the curing speed is slow and the composition is far from the cultural relic itself.The physical and chemical properties vary greatly,especially thermal expansion.This can easily cause the expansion and contraction of the adhesive material and the cultural relics to be out of synch,causing secondary damage to the cultural relics.In order to effectively overcome the above defects,this article tried to directly use the raw materials of the cultural relics to stick and paste the cultural relics,but all found problems such as stickiness and inconvenient operation.Therefore,this article believes that modifying the same materials of cultural relics to make them cohesive can effectively solve the problem of incompatibility between cultural relics and restoration materials.And this article take the ancient paintings of the Forbidden City and the Tang Dynasty lacquer plates as an example ’Because of the acid and alkali erosion,microbial destruction,and the sudden change of environment after excavation,the ancient lacquerware has been caused serious diseases,such as cracking,upwarping and peeling.Due to wind and sun exposure,insects destruction and acid rain erosion in the natural environment,ancient architecture paintings have suffered many kinds of diseases such as cracking,upwarping,peeling and falling off of the base layer.Lacquer paint film and ancient architecture paintings base layers are carriers of painted patterns and protective layers of fetal bones.They carry a lot of precious historical and cultural information.They are indispensable of lacquer ware and ancient paintings.Therefore,it has great significance to analyse and restore the lacquer film and ancient architecture paintings.In order to solve the above problems,this paper takes ancient lacquerware and ancient architecture paintings as its main research object,and conducts disease investigation and process analysis.Based on the analysis results,it has developed special adhesives for ancient lacquerware and ancient architecture paintings.It provides special materials for cracking and upwarping film of lacquerware and the base layer of ancient architecture paintings to avoid problems caused by the incompatibility of the repair material.This article mainly studies the following five aspects:1.Three cracking,upwarping,and peeling paint films of lacquerware were investigated and analyzed.Through elemental mapping,FTIR and other test analysis,it was found that the main components of the paint ash layer are lacquer and clay;The cause of the disease was discussed,mainly due to the severe degradation of the lacquer film during the burial process,and the hydrophilicity and water absorption rate were greatly increased.2.Through the modification of the lacquer,an adhesive-LA adhesive suitable for the lacquer film back paste was developed.The LA adhesive was evaluated by testing bond strength,cure time,flexibility,thermogravimetric analysis,film formation properties,and aging resistance.The results show that LA adhesive has high bond strength,fast curing in natural environment,smooth film formation,good flexibility,high temperature resistance and good durability.And preliminarily speculated the curing mechanism of adhesive by FTIR analysis.3.The chemical composition and production process of ancient architecture painting samples in the Changchun Palace were analyzed by elemental mapping,FTIR,microanalysis,and gas chromatography.It was found that the paints used in the ancient architecture paintings in the Changchun palace were Paris green,lapis lazuli,cinnabar,red lead,and white lead.The hemp fiber used in the base layer is 100%flax fiber,and the main components of the base layer are tung oil,pig blood,and clay minerals.4.Through the modification of the cooked tung oil,an adhesive-LT adhesive suitable for back pasting the ancient architecture base layer was developed.The LT adhesive was evaluated by testing bond strength,curing time,flexibility,thermogravimetric analysis,film formation properties,and aging resistance.The results show that the LT adhesive has higher bond strength,faster curing speed in natural environment,smooth film formation,good flexibility,high temperature resistance and durability.And preliminarily speculated the curing mechanism of adhesive by FTIR analysis.5.The LT adhesive was used for restoring the architectural paintings of Changchun Palace and Jiangxuexuan north house in the Palace Museum.It has been recognized and praised by ancient experts.