grantor:
University of TorontoThis thesis deals with the mesoscopic structure of self-assembled polymer and surfactant films and how it relates to macroscopic properties of wettability. Mesoscopic structure is defined as the regime between molecular, and macroscopic, with a typical scale of nanometers to a few microns. Polymer and surfactant films were prepared with varying mesostructure, and the morphology of the films was studied using atomic force microscopy (AFM). Static contact angles were then obtained in an effort to explore the effects that differing morphologies have on wettability. The particular films studied were solvent cast homopolymer, blend, and diblock copolymer films of polystyrene (PS) and polyethyleneoxide (PEO), and the surfactant used was octadecyltrichlorosilane (OTS). Several substrates were used including mica, fined silica, and silicon for the polymer films, and mica for the OTS. It was found that it was possible to prepare PS-PEO films with a diverse array of morphologies. A relatively new technique, phase detection imaging (PDI), is discussed as it relates to the interpretation of film morphology The contact angle measurements performed on the films proved to be very sensitive to the quality of the film. Finally, the polymer films and some films of OTS on mica were examined using phase detection imaging to try to gain insight into the origin of the phase contrast and to determine the best parameters to use in this imaging technique.M.Sc
