An ongoing interdisciplinary project on the development of polyvinylchloride (PVC) industry in the decade of the 1950s - 1970s, with particular focus of metal framed (PVC) coated windows and of historical PVC floors will be presented. Historical PVC windows are present in architecturally significant protected buildings and it is of a highest importance to understand these materials and to learn how they change and how we can best preserve them. The Museum für Stadt- und Industriegeschichte Troisdorf (MUSIT) has a significant written and material historical archive documenting the history of PVC industry and are partners in this project. Historical buildings and interiors have been identified where these materials have been used. In 1937, the entrance hall of Henkel AG in Düsseldorf was also covered with a PVC floor which has survived to this day. However, these objects are gradually disappearing as these are replaced with modern variants, their conservation is not considered, with loss of an integral original part of historical buildings of heritage interest. The degradation of PVC based objects in museum environment has been reported [1, 2] however these cannot be directly translated to built heritage context where factors such as outdoor environment, mechanical and chemical stress are an important degradation / ageing parameters. Our first analysis of a selection of PVC samples from archival, well dated and documented metal framed PVC coated windows by Py-GCMS and SEM-EDX shows that throughout the first years of production, different strategies have been used, for example the change from internal (copolymerization of PVC) to external plasticizers[3] which can have an impact in the long-term stability due to external plasticizer migration.[2, 5] The choice of additives (pigments, fillers, stabilizers) also varies which has an impact on dechlorination rate of PVC, and consequently its mechanical properties. In the current presentation the background of the project and these results will be presented.
Literature: [1] Da Ros S, Curran K, Del Gaudio I, et al., Proceedings of the 19th ICOM-CC Triennial Meeting Beijing 2021. [2] Shashoua Y. R., Polymer Degradation and Stability 2003; 81(1): 29–36 DOI/10.1016/S0141-3910(03)00059-4 [6] Wang C., Johnson D., Suleman M. A., et al. Polymer 2015; 76: 70–9. [3] Ferreira, E.S.B., Michel R., Waentig F., Fischer B., Liesen P., Hofmann V., Metalla 2023; SI 12: 114–6. [4] Yuan J, Cheng B., Sci Rep 2017; 7(1): 9277 DOI/10.1038/s41598-017-10159-7 [5] King R, Grau-Bové J, Curran K., Herit Sci 2020; 8(1) DOI/10.1186/s40494-020-00466-0
