Effect of Fluorinated Surface-Modifying Macromolecules on the Molecular Surface Structure of a Polyether Poly(urethane urea)

Fluorinated surface-modifying macromolecules (SMMs) have been developed to preferentially migrate to the surface of poly(urethane urea)s (PEUs), thereby modifying the surface features of the polymer. In the current study, four specific SMMs based on different chemistries were synthesized and incorporated at a 4 wt % concentration in the PEU. The domain structure at the surface was altered, and the nature of the interactions between the SMM and the base polymer was dependent on the defined SMM chemistry. The surface features were characterized by several microscopy techniques. Attenuated total reflectance infrared spectroscopy showed that, in blending with the PEU, some SMMs disrupted the existing hydrogen-bonded hard segment domain structure at the surface. However, this was not a necessity for good dispersion into the base polymer, as one SMM demonstrated good mixing within the PEU, forming SMM−PEU interactions while simultaneously maintaining the hydrogen bonding within the PEU hard segment domains. These studies demonstrate the importance of understanding both the physical and chemical aspects of the defined fluorinated SMM−PEU interactions in order to comprehend their specific surface characteristics.