Characterization of Solution-Cast Extracts from Cardiothane-51 ® by FT-IR and ESCA

Extracts from Cardiothane-51 ® have been cast from solvents of varying polarity. Cardiothane-51® can be described as block polyether-polyurethane copolymer with a 10% by weight addition of polydimethylsiloxane (DMS) that is partially copolymerized and partially blended to form a copolv mer/polv blend. FT-IR has been utilized to probe bulk and near-surface bonding and composition in the solution-cast extract films. Results show that Cardiothane-51 ® is similar in bulk composition, as measured by FT-IR, to Avcothane-51®. However, these two polymers are quite different in composition over a depth of microns. Both Cardiothane-51 ® and Avcothane-51 ® have surfaces, as measured by ESCA, which are dominated by their DMS component with a significant amount of the polyether present. Results suggest that the DMS in Cardiothane-51 ® is a blended phase, because of its ease of extraction.