Polysulfone (PSU), polyethersulfone (PESU), and polyphenylsulfone (PPSU) are aromatic, amorphous thermoplastics that demonstrate resistance to prolonged exposure to water, chemicals, and temperatures. Such performance is ideal for exterior applications where contact with atmospheric particulates and chemicals occur. Therefore, sulfone polymers have received a considerable amount of attention in high performance composites and coatings for aerospace industries. For such applications, the properties desired at the polymer surface, such as adhesion, wettability, gas impermeability, and low coefficient of friction are often distinct from the bulk properties of the material. Current research focuses on the surface modifications of these polymers, while the structural basis of the macroscopic properties of unmodified sulfone polymers is not fully understood. A fundamental understanding of the relationship between the surface properties of the polymer films and the solutions from which they are cast could allow for easier processing and more cost effective procedures. The effect of chemical structure and chain rigidity of PSU, PESU, and PPSU on the rheological data, surface tension parameters, and surface morphology was investigated. Polymer solutions of varying molecular weight and low distribution were characterized via gel permeation chromatography. Solution rheology experiments were carried out in order to characterize the viscoelastic properties of the polymer solutions of varying concentration, molecular weight, and chemical structure. Resulting surface morphology and roughness of the solution cast films was measured via atomic force microscopy. Results indicate that slight changes in chain rigidity and molecular weight have a significant effect of the rheological behavior of the polymer solutions and that these properties can be manipulated to tailor the sulfone polymer surfaces.
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