Picture of neon light reading 'Open'

Discover open research at Strathprints as part of International Open Access Week!

23-29 October 2017 is International Open Access Week. The Strathprints institutional repository is a digital archive of Open Access research outputs, all produced by University of Strathclyde researchers.

Explore recent world leading Open Access research content this Open Access Week from across Strathclyde's many research active faculties: Engineering, Science, Humanities, Arts & Social Sciences and Strathclyde Business School.

Explore all Strathclyde Open Access research outputs...

Determination of the ethylene oxide content of polyether polyols by low-field H-1 nuclear magnetic resonance spectrometry

Nordon, A and Meunier, C and Carr, R H and Gemperline, P J and Littlejohn, D (2002) Determination of the ethylene oxide content of polyether polyols by low-field H-1 nuclear magnetic resonance spectrometry. Analytica Chimica Acta, 472 (1-2). pp. 133-140. ISSN 0003-2670

Full text not available in this repository. Request a copy from the Strathclyde author

Abstract

Methods have been developed and compared for the analysis of a glycerol-based polyether polyol using a low-field, medium-resolution NMR spectrometer, with an operating frequency of 29 MHz for 1 H. Signal areas in the time and frequency domains were used to calculate the ethylene oxide (EO) content of individual samples. The time domain signals (free induction decay) were analysed using a new version of the direct exponential curve resolution algorithm (FID-DECRA). Direct analysis of the H-1 NMR FF spectra gave percentage EO concentrations of reasonable accuracy (average percentage error of 1.3%) and precision (average RSD of 1.8%) when compared with results derived from high-field C-13 NMR spectrometry. The direct FID-DECRA method showed a negative bias (-0.8+/-0.12% w/w) in the estimation of percentage EO concentration, but the precision (average RSD of 0.9%) was twice as good as that of direct spectral analysis. When the 13C NMR analysis was used as a reference method for univariate calibration of the 1 H NMR procedures, the best accuracy (average percentage error of 0.5%) and precision (average RSD of 0.6%) were obtained using FID-DECRA, for EO concentrations in the range 14.8-15.5% w/w. An additional advantage of FID-DECRA is that the analytical procedure could be automated, which is particularly desirable for process analysis. (C) 2002 Elsevier Science B.V. All rights reserved.