9303032 Gardella This research deals with studies directed at understanding the structure and reactivity of polymer surfaces. A special focus of the research program is emphasis on refining surface-sensitive spectroscopic measurements to derive structure, bonding, and reactivity information from macromolecular surfaces. In particular, model systems are constructed by Langmuir-Blodgett (LB) techniques to determine the qualitative and quantitative capabilities, and sampling depths of Secondary Ion Mass Spectrometry (SIMS), High Resolution Electron Energy Loss Spectrometry (HREELS), and angle and energy dependant Electron Spectroscopy for Chemical Analysis (ESCA or X-Ray Photoelectron Spectroscopy, XPS). Results from SIMS, ESCA and infrared spectroscopic methods are combined with surface energetics, thermal analysis, electron microscopy, and other more established methods in addressing three general problems in polymer surface science. One focus is to provide quantitative descriptions of the surface reactivity of thin molecular, monomer, and polymer films prepared by LB and "self-assembly" methods. A second group of projects aims to describe the near-surface composition and structure of selected multicomponent and multiphase polymers, especially those which are phase separated. Emphasis is placed on determining the effects of preparation and evaluating the composition as a function of depth. The third area of investigation involves surface chemical modification of fluoropolymers using both low-wattage plasmas and chemical reactions. The studies for the next three-year period build on the previous work, and the new research program will emphasize the use of quantitative SIMS methods study interfacial polymer chemistry. This research aims to develop quantitative methods of measuring the composition of polymer surfaces. This type of information in essential for an understanding of such applications as adhesion and biocompatibility. ***
