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Updated: Oct 4, 2026

MALDI-ToF MS Method for the Characterization of Synthetic Polymers with Varying Dispersity and End Groups
Published on: October 3, 2025
NMR characterization of functional groups: 9--isomer ratios of available chloromethylstyrene mixtures
S L Manatt1, G D Khune, N A Khatri
1Jet Propulsion Laboratory, California Institute of Technology, Pasadena 91109, USA.
Abstract:
From the assignments of the 1H and 13C 11.7 tesla NMR spectra of available mixtures of m- and p-chloromethylstyrene, the proportion of the meta and para compounds are easily determined. For these materials from two common commercial sources, proportions of 72 and 28% and 68 and 32% were found. These concentrations are substantially different from the often assumed 60 and 40% for the meta and para compounds, respectively. The influence of this difference on the desired properties of copolymers made from such mixtures is discussed. An alternative quantitative procedure for determining the chloromethyl group isomer ratios is also described which employs silver trifluoroacetate in acetone displacement of chloride and 19F NMR examination of the resulting ester mixture with a 2.3 tesla spectrometer.
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