Influence Analysis of Polyvinyl Alcohol on the Degradation of Artificial Leather with Cellulose Nitrate Coating Originating from a Suitcase Stored in the Collection of the Auschwitz-Birkenau State Museum in Oświęcim, Poland

The aim of this study was to assess the influence of a protective layer of polyvinyl alcohol on the degradation process of artificial leather based on cellulose nitrate. Samples of the artificial leather were obtained from a suitcase dating back to the first half of the 20th century, not considered a historical artifact. The analysis involved Fourier-transform infrared spectroscopy with attenuated total reflection (FTIR-ATR) and X-ray photoelectron spectroscopy (XPS). Artificial aging was employed for the study. The artificial leather sample with a protective coating of polyvinyl alcohol on a cellulose nitrate base exhibited the lowest degree of degradation due to minimal chemical changes in cellulose esters. The obtained FTIR-ATR spectrum indicated significantly higher nitration of cellulose and, consequently, a lower degree of polymer degradation. The sample without the protective polyvinyl alcohol coating and the sample with the coating removed before artificial aging showed similar reactions.