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  • Compositional analysis of multilayered plastic constituents and constituent mixtures using benchtop 1 H NMR spectroscopy
Title: Compositional analysis of multilayered plastic constituents and constituent mixtures using benchtop 1 H NMR spectroscopy
Multilayered plastics are widely used in food packaging and other commercial applications due to their tailored functional properties. By layering different polymers, the multilayered composite material can have enhanced mechanical, thermal, and barrier properties compared to a single plastic. However, there is a significant need to recycle these multilayer plastics, but their complex structure offers significant challenges to their successful recycling. Ultimately, the use and recycling of these complex materials requires the ability to characterize the composition and purity as a means of quality control for both production and recycling processes. New advances and availability of low‐field benchtop1H NMR spectrometers have led to increasing interest in its use for characterization of multicomponent polymers and polymer mixtures. Here, we demonstrate the capability of low‐field benchtop1H NMR spectroscopy for characterization of three common polymers associated with multilayered packaging systems (low‐density polyethylene [LDPE], ethylene vinyl alcohol [EVOH], and Nylon) as well as their blends. Calibration curves are obtained for determining the unknown composition of EVOH and Nylon in multilayered packaging plastics using both the EVOH hydroxyl peak area and an observed peak shift, both yielding results in good agreement with the prepared sample compositions. Additionally, comparison of results extracted for the same samples characterized by our benchtop spectrometer and a 500‐MHz spectrometer found results to be consistent and within 2 wt% on average. Overall, low‐field benchtop1H NMR spectroscopy is a reliable and accessible tool for characterization of these polymer systems.  more » « less
Award ID(s):
2132093
PAR ID:
10562251
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Magnetic Resonance in Chemistry
Volume:
62
Issue:
8
ISSN:
0749-1581
Page Range / eLocation ID:
619 to 628
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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