Morphological studies were performed on a polymer blend, used as a friction bearing, consisting of polyamide 6.6 (80%), poly-(tetrafluoroethylene) (18%), and silicone oil (2%). Raman imaging, FT-IR imaging, scanning electron microscopy with energy-dispersive X-ray spectrometry, and microthermal analysis determined the distribution of poly(tetrafluoroethylene) clusters in the polyamide matrix. Each characterization method allows qualitative identification of the main components and provides information about cluster size and distribution. It is proved that poly(tetrafluoroethylene) clusters of 10 to 30 μm are randomly distributed in a polyamide matrix and that silicone oil can be found at the cluster matrix interface. The good agreement that was obtained in our investigations indicates high reliability of the results since all applied methods are based on different chemical and physical properties. This combined approach revealed information about the morphology of the blend for a better understanding of its working principle and enhanced knowledge for its processing. A comparison of the different methods employed in this study highlights their advantages and limitations for polymer analyses.

Kinetics of solvent diffusion (chloroform) and solvent-induced crystallization in syndiotactic polystyrene (sPS) were investigated by Fourier transform infrared (FT-IR) transmission imaging and single element detector transmission FT-IR spectroscopy. Spatially resolved information from FT-IR imaging experiments under controlled environmental conditions (temperature and solvent vapor pressure) and with uniaxial solvent diffusion into the polymer was used to monitor the appearance of δ crystalline sPS as a function of solvent exposure time. From a series of time-resolved FT-IR images polymer crystallization kinetics at various positions in the polymer and solvent diffusion coefficients were determined. The imaging experiments proved that solvent diffusion is the limiting factor in the overall crystallization process of a sPS sample. FT-IR images revealed that the full extent of crystallinity is reached before the equilibrium concentration of the solvent in the semicrystalline polymer is established at any location in the sample. Single element detector transmission FT-IR measurements indicated that the kinetics of the crystallization process strongly depends on solvent vapor pressure. A critical value of solvent concentration in the polymer needs to be achieved in order to observe any polymer crystallization. This critical value and the crystallization kinetics in a solvent saturated atmosphere were also revealed.