The diploma thesis deals with the preparation, crosslinking and characterization of collagen films from various animal sources. Collagen from pig, Tilapia, horse, cow and crocodile was used to prepare collagen films. Chemical crosslinking agents EDC/NHS and Lyofix were used to crosslink the prepared films. In the experimental part, differential scanning calorimetry (DSC) method was optimized to determine the denaturation temperature of individual collagen films before and after crosslinking. In addition, the ability of films to swell and degrade has been analyzed. The presence of characteristic groups present in the collagen structure was verified using infrared spectroscopy. The sample morphology was analyzed using Scanning Electron Cryomicroscopy (Cryo-SEM). The results show that EDC/NHS is a better collagen crosslinking agent compared to Lyofix. The best source for the preparation of thermally stable films is piggy collagen, whose denaturation temperature after crosslinking with EDC/NHS was about 69 °C and could represent more than adequate substitution for cow collagen, which is currently most used in the field of tissue engineering and food industry.

The thesis deals with determination the type, composition and structure of rubber materials comming from gas masks produced withing sixteen years. Rubber materials were tested to determine if storage conditions could influence or caused the change in composition and/or the structure. To judge it rubber specimens were exposed to termo-oxidative aging at 75 and 105 °C for 50 ad 20 days, respectively, to obtain data for comparison. Termogravimetry Fourie-transform Infrared Spectroscopy with Attenuated Total Reflection and Differential Scanning Calorimetry were used to characterize composition/structure of tested speciments. Thermo-oxidative aging at 75 °C led to degradation of additives in both types of rubber, at 150 °C also to chemical degradation of rubber network especially in case of NR (glass transition temperature increases with aging time). Neither additives or rubber network was degraded in original rubber specimens. Deterioration of mechanical and, thus, utility properties of gass masks are not supposed any they are recommended to safe usage.