A simple Fourier transform infrared (FTIR) method using Photoacoustic (PA) detection is used to detect external lubricants directly on the surface of styrenic resin pellets. This technique is non-destructive, requires no sample preparation and rapidly determines the lubricant chemical class. This rapid qualitative procedure significantly reduces the subsequent quantitative analysis time of unknown samples. The application of PA-FTIR and the advantages of applying spectral subtraction in identifying fatty acid and substituted fatty amide external lubricants on some styrenic resins will be presented.
K. E. Yock,
"PA-FTIR Detection Of External Lubricants In Styrenic Polymers", Proc. SPIE 1145, 7th Intl Conf on Fourier Transform Spectroscopy, (1 December 1989); doi: 10.1117/12.969383; https://doi.org/10.1117/12.969383