NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.
Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.
An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Time-gated Raman spectroscopy of recovered plastics
Published
Author(s)
Anthony Kotula, Sara Orski, Kayla Brignac, Jennifer Lynch, Bryan Heilala
Abstract
Raman spectroscopy is a powerful non-destructive technique for the identification and characterization of plastics. The technique often has limited use due to fluorescence emission, which often occurs in polymer samples containing colorants or that have been subjected to weathering and degradation. Here, we demonstrate that time-gated Raman spectroscopy can be used to successfully characterize recovered plastics that exhibit strong background fluorescence due to the presence of additives and dyes. Time-gating removes a significant amount of background signal from the Raman spectra such that the polymers and color additives can be identified using similar measurement times compared to continuous-wave Raman spectroscopy. Examples of this are shown for blue samples containing an organic dye and a white sample containing titanium dioxide. This technique can also be used to characterize samples that are black in color due to carbon-based additives like graphite, which can be challenging to characterize via other common vibrational spectroscopic techniques.
Kotula, A.
, Orski, S.
, Brignac, K.
, Lynch, J.
and Heilala, B.
(2022),
Time-gated Raman spectroscopy of recovered plastics, Marine Pollution Bulletin, [online], https://doi.org/10.1016/j.marpolbul.2022.113894, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=934175
(Accessed October 7, 2025)