INFRARED STUDIES OF NOVEL OPTICALLY RESPONSIVE MATERIALS - ORIENTATION CHARACTERISTICS OF SULFONATED POLYSTYRENE POLY(DIALLYLDIMETHYLAMMONIUM CHLORIDE) IONIC POLYMER MULTILAYERS ON PATTERNED SELF-ASSEMBLED MONOLAYERS/

Polarization modulation infrared reflection absorption spectroscopy (P M-IRRAS) is utilized in the characterization of a new class of polymer ic materials that exhibit unique optical properties, The differential nature of PM-IRRAS, coupled with the fact that the experiment was perf ormed on a commercially available hardware setup, makes the technique ideal for studying selectively deposited polyion multilayers on metal surfaces, The system under study was a polymeric thin film of alternat ing bilayers of sulfonated polystyrene/poly(diallyldimethylammonium ch loride) (SPS/PDAC) fabricated by ionic multilayer assembly, Specifical ly, patterned self-assembled monolayers (SAMs) of omega-functionalized alkane thiolates were used as the molecular template. Alternating lay ers of polyanion and polycation were then selectively adsorbed onto sp ecific regions of the surface to form a patterned films of thicknesses from 150 to 400 Angstrom. The total thickness of the him was measured at 150 Angstrom with the use of ellipsometry, Polyion conformation pl ays a crucial role in the selectivity of the patterned film, film surf ace characteristics, and ultimately, the ability of these systems to f unction as optical devices, The infrared spectroscopic data give insig ht into chemical composition and conformation and show that the molecu lar orientation of polyions in these polymeric multilayer structures d epends on the ionic content of the initial solutions.