In my thesis, I investigated the thermal properties of four dried hydrogels (xerogels) and their lyophilized versions with different compositions. The materials used for the synthesis of these hydrogels were gelatin, Pluronic F-127 copolymer, phytic acid (PA), and tannic acid (TA). I studied the thermal properties using TG-MS, DSC, thermooptometry, and heating on a hot plate. The different ratios of the raw materials in the hydrogels and the lyophilization process influenced the glass transition temperature (T$_g$), thermal stability, and the shape of the DSC curves. The lyophilized samples showed a significantly smaller second endothermic peak compared to the xerogels. Based on TGMS measurements and the signals for water, I associated this peak with the release of
water. The best applicative properties were shown by hydrogel HG80, which contained all the aforementioned materials in the ratio gelatin:F-127:PA:TA = 3:2:1:0.1, and its lyophilized form HG80-L, on which I performed thermo-optical measurements and heating on a hot plate. I confirmed the softening of the samples in the temperature range of the glass transition, as determined by DSC, that is, in the body-friendly temperature range between 40–50 °C. The findings contribute to the development of further hydrogel formulations and the understanding of their thermal properties.
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