镇安寺铁牛表层油漆膜清除及其溶解性能分析

Cleanup of the oil paint from the surface layer of a Zhen’an Temple iron bull and analysis of the dissolution performance

镇安寺铁牛其表面锈蚀严重,如何配制出既不伤害铁牛文物基体,又能快速清除其表层油漆的新型清洗试剂,以达到彻底清洗的目的,本研究采用体积比为1∶1的丙酮、二甲基亚砜混合试剂并利用敷盖法(脱脂棉加保鲜膜)可快速、高效地清除镇安寺铁牛表层油漆。基于铁牛漆膜的溶胀试验照片与傅里叶红外光谱图,可确定漆膜的最佳溶胀试剂;采用扫描电子显微镜、能谱仪可检测该清洗试剂对铁牛基体无任何损伤;利用高聚物的“三维溶度参数”概念可解释丙酮、二甲基亚砜混合试剂对漆膜的溶胀作用以及理论推测其最优溶剂体积比;利用敷盖法,采用吹风机对混合试剂浸泡潮湿起翘的油漆膜进行热吹风,可快速吹掉铁牛表层漆膜,效果良好。

In this work,a mixture of acetone and dimethyl sulfoxide(volume ratio 1∶1)and a particular covering method using degreasing cotton and preservative film was applied to remove the oil paint from the surface of a Zhen’an Temple iron bull.The solvent mixture and the covering method quickly and efficiently removed the oil paint film.The optimum mixed reagent for dissolving the oil paint film was selected by referring dissolution experiment photographs and Fourier transform infrared spectra.Besides,scanning electron microscopy and energy dispersive spectrometry were employed to test the dissolution behavior of the mixed reagent.The mixed reagent could dissolve the oil paint film without harming the iron bull matrix.The concept of"three dimensional solubility parameters"was applied to explain the dissolution action of the mixed reagent.Additionally,the theoretically optimum solvent volume ratio of the mixed reagent could also be inferred using the concept.The covering method and a hair drier were adopted to purge the damp and warped oil paint film after the immersion in the mixed reagent.This thermal drying method could quickly blow off the paint film from the surface layer of the Zhen’an Temple iron bull with a good effect.