Temperature-dependent infrared refractive index of polymers from a calibrated attenuated total reflection infrared measurement
Date
2022
Authors
Azam, Md S.
Ranson, Malcolm D.
Hore, Dennis K.
Journal Title
Journal ISSN
Volume Title
Publisher
Applied Spectroscopy
Abstract
We demonstrate a straightforward method by which a commonly available reference sample such as water can be used to
calibrate an attenuated total internal reflection infrared absorbance measurement in order to account for the polarization of the
beam incident on the internal reflecting element, and the spread of angles about the nominal angle of incidence. This enables
quantitative comparison of attenuated total reflection-derived absorbance data with spectra calculated from optical constants.
We then apply this calibration to the measurement of temperature-dependent absorption spectra of a polydimethylsiloxane
sample. We illustrate that the extracted optical constants scale with the temperature-dependent changes in the polymer density
better than the raw absorbance values on vibrational resonance.
Description
Keywords
Attenuated total reflection infrared spectroscopy, ATR-IR, polarization, susceptibility, complex refractive index, temperature-dependence, polymers
Citation
Azam, M. S., Ranson, M. D., & Hore, D. K. (2022). “Temperature-dependent infrared refractive index of polymers from a calibrated attenuated total reflection infrared measurement.” Applied Spectroscopy, 76(10), 1254-1262. https://doi.org/10.1177/00037028221094598