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The scope of the present work is to study the biodegradability behavior of several novel heterocyclic poly(ether urethanes) when their hard segments are subjected to exposure to the Alternaria tenuissima fungus. The heterocyclic poly(ether urethanes) were chain-extended with various pyridine derivatives that had different functional groups placed in different positions on the pyridine rings. Different ratios of the reactive components were also used. The measurements obtained by the use of the attenuated total reflectance-Fourier transform infrared spectroscopy revealed the different structural changes that occurred after exposure to fungi. The degradation process was analyzed through measurement of the mechanical properties and surface morphology evolution by scanning electron microscopy. The obtained results show that the nature and design of the functional groups on the pyridine ring determine the strength of the cohesion linkages that in turn influence different degradation behaviors under exposure to fungi. (c) 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46096.

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This research shows the fungal degradation behavior of two series of composites: a series obtained with silver powder incorporated in sulfadiazine (SD)-based polyurethane urea and another series of composites that incorporates silver through polyurethane chain extension with silver SD. This article reports on the chemical structure variations characterized by Fourier transform infrared (FTIR) spectroscopy and the mechanical properties of these polymers before and after fungal exposure. Although silver SDused as a chain-extenderensures a more orderly dispersion of the silver throughout the hard segment of the polyurethane urea main chain, the FTIR results showed some changes on the surface of these composite films. Both silver composites exhibited higher fungal biodegradation resistance.

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