Construction of microphase separated structure and blood compatibility of segmented polyurethanes with fluoroalkyl group

Segmented polyurethanes consisting of the soft segment with polyethylene glycols(PEG) possessing a higher surface free energy and the hard segment with fluoroalkyl groups possessing a lower surface free energy were prepared. Also, both of PEG and fluoroalkyl groups used in this study have excellent biocompatibility. The surface characteristics of segmented polyurethanes in various environments was investigated by means of X-ray photoelectron spectroscopy (XPS) and dynamic contact angle measurements. These measurements revealed that in a hydrated state, the hydrophilic soft segment with PEG was enriched on the surface in order to minimize the interfacial free energy between water and the solid surface, and the degree of the PEG's migration was changed according to the chain molecular motion and microphase separation state of bulk. It was clearly marked that the blood compatibility of segmented polyurethanes was good for SPU having a microphase separation structure at the surface in a hydrated state.