AVS 46th International Symposium
    Applied Surface Science Division Thursday Sessions
       Session AS-ThA

Paper AS-ThA9
Angle Resolved XPS Study of Random Fluoro-methacrylate Copolymers

Thursday, October 28, 1999, 4:40 pm, Room 6A

Session: Polymer Surfaces, Films, and Interfaces
Presenter: W.E. Kosik, Army Research Laboratory
Authors: W.E. Kosik, Army Research Laboratory
S.H. McKnight, Army Research Laboratory
J.M. Deitzel, Army Research Laboratory
N.C. Beck Tan, Army Research Laboratory
Correspondent: Click to Email
Design and control of polymer surface functionality is desirable for numerous applications. It is widely known that hydrophobic polymer surfaces can be produced on block-copolymers due to surface segregation of hydrophobic blocks, including flouro and siloxane species. Less research has been performed on random copolymer compositions. In this work, we investigate the surface segregation of a random copolymer of polymethylmethacrylate (PMMA) and tetrahyrdorperflouroctyl acrylate (PTAN). Copolymers containing different ratios of the two repeat units were examined. Thin films (150-200 nm) were solution spun-cast onto silicon substrates. As-deposited and samples annealed above the copolymer glass transition temperature were studied to assess the degree of surface reorganization that might occur. Angle resolved XPS was used to study the fluorine content of the thin films as a function of depth. It was observed that the concentration of fluoro groups increases near the surface of the film in all compositions. The degree of surface segregation was dependent on the PTAN to PMMA ratio of each copolymer. Furthermore, the segregation was enhanced after annealing of the films at elevated temperatures. Water contact angle measurements were in agreement with the angle resolved XPS results. Potential applications of these materials for selectively permeable membranes are discussed.