FOURIER-TRANSFORM INFRARED AND RAMAN STUDIES OF COATINGS

Fourier transform (FT) IR reflectance measurements were used to monitor the top surface and back-interface curing processes of a polyurethane system. Problems associated with the reflectance technique are discussed. Additionally, the fundamental kinetic parameters for bulk film cure, obtained by nonisothermal FTIR measurements, were combined with a model for polymer network growth to predict the buildup in modulus of the curing film. The results were in excellent agreement with experimental data. Processing conditions for polyester coatings play a significant role in the behavior of the final film. FT Raman measurements were performed on coatings based on polyethylene terephthalate-isophthalate to demonstrate structural reordering of polymer chains during heat treatments.