Fourier transform infrared spectroscopy using diffuse reflectance optics (DRIFT) can be used as a quick, non-destructive and direct technique for the characterization of polymeric materials and products. The spectra obtained do not appear as normal infrared spectra because of specular and diffuse Fresnel reflections. The bands are distorted with first-derivative-like appearance. Mathematical differentiation results in characteristic high-resolution second-derivative-like spectra which are suitable for interpretation. The DRIFT technique is capable of analysing surface related phenomena and structural information is provided of polymer layers up to nanometer level thickness. Molecular orientation of polymeric materials can be characterized without using a polarizer.
Jan Jansen, Jan Jansen,
"Diffuse Reflectance Fourier Transform Infrared Spectroscopy Of Polymers", Proc. SPIE 1145, 7th Intl Conf on Fourier Transform Spectroscopy, (1 December 1989); doi: 10.1117/12.969638; https://doi.org/10.1117/12.969638