Elsässer Christina, Mayr Veronika, Montag Peter, Angelin Eva Mariasole, Hilbig Harald, Grosse Christian Ulrich, Pamplona Marisa
Conservation Science Department, Deutsches Museum, Museumsinsel 1, 80538 Munich, Germany.
Chair of Non-destructive Testing, Technical University of Munich, Franz-Langinger-Straße 10, 81245 Munich, Germany.
Polymers (Basel). 2023 Feb 8;15(4):852. doi: 10.3390/polym15040852.
The preparation of mock-ups in heritage science studies represents a valid alternative for investigation purposes, avoiding extensive sampling of cultural heritage objects. This work presents for the first time the successful preparation of three dimensional (3D) mock-ups made of celluloid, considering a combination of historical industrial production strategies and small-scale lab facilities. Prefabricated transparent celluloid sheets were acquired and then shaped through compression molding for creating mock-ups with 3D geometries. These reflected common and representative shapes encountered in the collection of the Deutsches Museum. Visual inspection of the mock-ups allowed determining the best compression molding conditions. Attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR) confirmed the absence of molecular heterogeneity due to the processing method. Artificial aging of the mock-ups was conducted to reach degradation states comparable with naturally aged objects. ATR-FTIR investigation offered first insights into the induced artificial degradation. Ion chromatography (IC) and gel permeation chromatography (GPC) analyses allowed to assess the extent of the artificial aging of the celluloid mock-ups and confirmed the occurrence of loss of camphor, denitration, and main chain polymer scission, the latter being the predominant decay path. The comparison with historical objects highlighted that the mock-ups are representative of moderately aged artifacts. As such, this study paves the way for implementing moderately aged celluloid 3D mock-ups in heritage science research, enabling in-depth testing for the scope of conservation.
在遗产科学研究中制作模型是一种有效的调查替代方法，可避免对文化遗产对象进行大量采样。这项工作首次展示了成功制备由赛璐珞制成的三维（3D）模型，考虑了历史工业生产策略和小规模实验室设施的结合。获取预制的透明赛璐珞片，然后通过压缩成型进行塑形，以创建具有3D几何形状的模型。这些模型反映了德国博物馆藏品中常见和具有代表性的形状。对模型的目视检查有助于确定最佳的压缩成型条件。衰减全反射傅里叶变换红外光谱（ATR-FTIR）证实了由于加工方法导致的分子异质性不存在。对模型进行人工老化处理，以达到与自然老化物体相当的降解状态。ATR-FTIR研究首次深入了解了诱导的人工降解情况。离子色谱（IC）和凝胶渗透色谱（GPC）分析能够评估赛璐珞模型的人工老化程度，并证实了樟脑损失、脱硝和主链聚合物断裂的发生，其中主链聚合物断裂是主要的降解途径。与历史文物的比较突出表明，这些模型代表了中等老化程度的文物。因此，本研究为在遗产科学研究中应用中等老化程度的赛璐珞3D模型铺平了道路，能够针对保护范围进行深入测试。
