Practical analysis of polymers with depth varying compositions using Fourier transform infrared photoacoustic spectroscopy (plenary)

摘要

Fourier transform infrared photoacoustic spectroscopy can be used as a nondestructive method to probe the molecular composition of materials as a function of depth into the sample. This is done by varying the thickness of the surface layer being analyzed, which can be as great as some tens of micrometers, depending on optical and thermal properties.Computational methods are described to process photoacoustic amplitude and phase spectra for both semiquantitative and quantitative depth analyses. These methods are demonstrated on layered and gradient samples.