Fourier transform infrared (FTIR) authentication and batch-to-batch consistency for different types of paints using benchtop and handheld FTIR spectrophotometers for oil and gas industry

• Published in: Polymer Engineering and Science
• Main Author: Salim Y.S.; Rashid N.A.; Halim S.I.A.; Chan C.H.; Ong C.H.; Harun M.K.
• Format: Article
• Language: English
• Published: John Wiley and Sons Inc 2021
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85108593727&doi=10.1002%2fpen.25746&partnerID=40&md5=9bc0de95a8c1a802f0ba2f88ed4af23d

Standardization of Fourier transform infrared (FTIR) fingerprint region for paints and assessment on the reproducibility using different spectrophotometers were investigated. While selective fingerprint regions may be confusing for technicians/analysts who are non-chemists, we attempt to generalize these regions (e.g., 1300–1000 cm−1 for Epoxy part A and 1400–1000 cm−1 for Epoxy part B) by choosing a universal region (2000–900 cm−1) that works for different paints. Comparison result using a paired student t-test shows that the degree of similarity (r) values from the studied regions are not statistically different. The paint fails the screening analysis occasionally on-site when analyzed using handheld FTIR due to the higher level of noise that gives low r values (r < 0.900 ± 0.002). The same samples were analyzed using a benchtop FTIR and the r values are above 0.900 ± 0.002. While the screening may lead to a false rejection of the sample on-site, there could be occurrence of false acceptance. The on-site screening of EPZ part A with different formulations, for instance, shows that the r values over the entire IR spectrum are above 0.900 ± 0.002 when analyzed using handheld FTIR. After the samples were analyzed using the benchtop, the r values fall below 0.900 ± 0.002. © 2021 Society of Plastics Engineers.