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Simple Trends in the Methylene Regions of the NMR Spectrum of Poly(propylene) and Ethylene-Propylene Copolymers

✍ Scribed by Guglielmo Monaco; Irene Sessa; Adolfo Zambelli

Publisher: John Wiley and Sons
Year: 2006
Tongue: English
Weight: 191 KB
Volume: 207
Category: Article
ISSN: 1022-1352
DOI: 10.1002/macp.200600091

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✦ Synopsis

Abstract

Summary: The configurational sensitivity of the chemical shift of methylene carbons has been analyzed theoretically in terms of a perturbative approach. Theoretical results and computations have been applied successfully to new experimental data obtained from model compounds of the ${\rm S}_{\alpha \beta}$ resonance. It has been shown that the carbon in $\beta$ position with respect to the first methine of a regioregular sequence follows the same simple trend of the corresponding carbon atoms in $\alpha$ position. The tiny chemical shift spreadings of the ${\rm S}_{\alpha \beta}$ resonance due to the relative configuration of the nearest methyl groups in $\alpha$ and $\beta$ position showed a single inversion with respect to theoretical expectation.

Decomposition of a chain in subchains.

magnified imageDecomposition of a chain in subchains.

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