Comparison of Photoacoustic and Diffuse Reflectance Infrared Spectroscopy as Near-Surface Analysis Techniques

Abstract

Fourier transform infrared photoacoustic spectroscopy (FT-IR/PAS) has been applied as a near-surface analysis technique for various types of samples. Diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) also was reported for characterizing surface species of fibrous materials. In this research, chemically modified textile fabrics, fibers, and films were studied by both FT-IR/PAS and DRIFT. The capability of near-surface analysis for both techniques was evaluated and compared. Even though diffuse reflectance infrared spectra show an enhancement in the band intensity of near-surface species, FT-IR/PAS appears to have a much smaller sampling depth than DRIFTS. All the data demonstrate that FT-IR/PAS is a useful near-surface analysis technique for polymeric fibers and films.