Surface and mechanical properties of some new biopolyurethane composites

Surface tension parameters and morphology of biopolyurethane composite surfaces based on natural polymers, before and after applying high frequency cold plasma treatment, have been evaluated. These surface tension parameters were calculated having on their basis the geometrical mean approach [Owens and Wendt, J Appl Polym Sci,13, 1741 (1969); Rabel Physicalische Blätter, 33, 151 (1977); and Kälble J. Adhesion, 1, 102 (1969)], acid/base method [Lifshitz‐van der Waals, van Oss et al., Langmuir,4, 884 (1988)], and on the theoretical methods involving quantitative structure–properties relationships (Bicerano). For all the investigated films, the polar terms contribute significantly to the total surface tension as due to the large electron donor interactions. High frequency cold plasma alters the surface energy of composites by changing their surface polarity and hydrophilicity. Hydrophile/hydrophobe balance was studied by means of the free energy of hydration and interfacial tension between biomaterials and water. Mechanical properties of the polyurethane biocomposites were investigated in comparison with those of the porcine carotid arteries. POLYM. COMPOS., 31:1956–1964, 2010.