2013 Volume 23 Issue 1 Pages 62-65
Recently, polymeric materials have been widely used in medical applications. In these cases, the surface is supposed to contact with a different phase. Thus, the polymer interfaces contacted with different phases should be studied, structurally and dynamically. Density profiles of a perdeuterated poly (methyl methacrylate) (dPMMA) film in water, hexane, methanol, ethanol, 1-propanol, and 1-buthanol were examined along the direction normal to the interface by neutron reflectivity (NR). Although these liquids are typical non-solvents for dPMMA, the liquid/polymer interfaces were diffuse in comparison with the air/polymer interface probably due to the partial dissolution of segments at the outermost region of the film. Interestingly, in water, the anomalous swollen layer was formed beneath the diffused interface. On the other hand, such a swollen layer was not observed for the dPMMA films in alcohols. This is simply because alcohol molecules deeply penetrated into the films. The amounts of the alcohols penetrated in the films could be explained in terms of the interaction parameter. The fractional amount of non-solvents at the substrate interface was higher than that in the internal region of the film. Furthermore, aggregation structure of poly (2-methoxyethyl acrylate) film, which has been used as a coating material for biomedical apparatus due to the excellent blood compatibility, was examined in water
