Silk is a natural protein polymer that, due to its exceptional mechanical properties, has
been used for millennia primarily in textile industry, thereby representing a valuable
element of cultural heritage. It is mainly composed of the protein fibroin, whose two
filaments form a core of a silk fiber, while being surrounded by the protein sericin, which
acts as an adhesive and protective layer.
As a part of my thesis, I dissolved acidic and neutral samples of non-weighted silk in
saturated solution of lithium bromide, measured their flow times using capillary
viscometer and calculated their molar mass using Mark-Houwink equation to demonstrate
larger degree of fibroin and silk degradation in an acidic environment. I also prepared
extracts of standard unweighted silk samples and samples subjected to accelerated
degradation and analyzed them using an ion chromatograph to examine the formation of
potential acidic anionic species during the aging process.
For further research, I attempted to optimize the method of dissolving silk, which had
been previously weighted with tin(IV) chloride, as it does not dissolve in a saturated
lithium bromide solution under standard procedure. I tested the effectiveness of pretreating the silk with the 0,5 M ammonia solution, degumming with an alkaline sodium
carbonate solution and a combination of both methods.
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