Multi-dimensional spectroscopy of polymer films; Surface and interfacial interactions

Behavior of macromolecules near surfaces and interfaces of polymeric thin f ilms and coatings may play a vital role in numerous applications. Therefore , understanding of molecular level processes responsible for durability, ad hesion, and many other macroscopic processes is of a particular importance. This presentation will focus on stratification processes in multi-componen t polymeric films, with particular emphasis to polymer-surfactant interacti ons in latexes, responsiveness of individual components during coalescence of water-borne polyurethanes, and behavior of thermoplastic olefins (TPO). The presence of macromolecular arrange-ments and interactions among various components near the film-air (F-A) and the film-substrate (F-S) interfaces can be effectively monitored using attenuated total reflectance (ATR) and step-scan photoacoustic (SS-PA) Fourier transform infrared (FT-IR) spectros copy. Both approaches are capable of obtaining information from various sur face depths and complement each other if one seeks molecular level informat ion from (C) 150 mu m into the film. If one combines ATR and PA information with IR and/or Raman surface imaging, it is possible to obtain a 3-dimensi onal representation of polymeric films.