Silk is a natural polymer consisting mainly of fibroin. Silk fibres are very sensitive to external influences, which can cause irreversible damage through reactions of oxidation and hydrolysis. Silk cultural heritage items are priceless, therefore understanding the processes of degradation and finding ways to monitor and evaluate the condition of silk is crucial for proper preservation and for limiting further degradation. In my master’s thesis I investigated the processes that are the main cause of silk degradation and analytical methods that are currently used to determine the condition of silk. Since we cannot use historical samples for destructive analysis, I prepared a large quantity of samples from fresh untreated and weighted silk, which I then exposed to UV light, elevated temperature and different relative humidities in connection with elevated temperatures. Afterwards I analysed reference and artificially aged samples using different methods, such as colorimetry, ATR-FTIR, SEM-EDS and XRD. I have found out that UV light, elevated temperature and relative humidity affect the condition and degradation of samples, therefore it is recommended that historical specimens are stored and exhibited at lower temperatures and moderate relative humidity and lighting. The monitoring and evaluation of silk degradation is a complex problem which provides us many different possibilities for further research, both in sample preparation, artificial aging and in the introduction of advanced analytical methods.
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