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Rapid quantitative H-C two-dimensional NMR with high precision. | LitMetric

Rapid quantitative H-C two-dimensional NMR with high precision.

RSC Adv

State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences Changchun 130022 China

Published: February 2022

AI Article Synopsis

Article Abstract

Two dimensional (2D) H-C heteronuclear single-quantum correlation (HSQC) spectroscopy has recently been proposed for quantitative determination of typical linear low density polyethylene (LLDPE) with high accuracy. It requires highly precise measurement to achieve further reliable quantification. In this context, this paper aims at determining conditions that allow the achievement of high precision. On the basis of the optimized parameters, two time-saving strategies, nonuniform sampling (NUS) and band-selective HSQC are evaluated on model polyolefins in terms of repeatability. Precision better than 0.3% and 5% for ethylene content ( mol%) and 1-hexene content ( mol%) of the model poly(ethylene--1-hexene)s are obtained with 50% NUS or band-selective HSQC. Moreover, dramatic precision enhancements can be achieved with the combination of band-selective HSQC and 50% NUS, in which repeatabilities better than 0.15% and 2.5% for mol% and mol% are observed. The experiment times are reduced to about 0.5 h. These methods open important perspectives for rapid, precise and accurate quantitative analysis of complex polymers.

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Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8981411PMC
http://dx.doi.org/10.1039/d1ra08423bDOI Listing

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