Applications of two-dimensional correlation spectroscopy in depth-profiling photoacoustic spectroscopy, near-infrared dynamic rheo-optics, and spectroscopic imaging microscopy

Two-dimensional infrared (2D IR) correlation spectroscopy has found diverse applications in characterizing polymers. The versatility of this powerful technique is demonstrated in the study of a polymeric laminate film by using depth-profiling photoacoustic spectroscopy, mid- and near-IR dynamic rheo-optical measurements, and spectroscopic imaging microscopy. Spatial and temporal variations of near-IR spectra are effectively analyzed by the 2D correlation technique. Step-scanning FT-IR spectrometers provide a unique opportunity to obtain desired spectral information often difficult to access by the conventional rapid-scanning approach.