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Application of (1)H DOSY for Facile Measurement of Polymer Molecular Weights.

ABSTRACT: To address the practical issues of polymer molecular weight determination, the first accurate polymer weight-average molecular weight determination method in diverse living/controlled polymerization via DOSY (diffusion-ordered NMR spectroscopy) is reported. Based on the linear correlation between the logarithm of diffusion coefficient (log D) and the molecular weights (log Mw), external calibration curves were created to give predictions of molecular weights of narrowly-dispersed polymers. This method was successfully applied to atom transfer radical polymerization (ATRP), reversible addition-fragmentation chain transfer (RAFT), and ring-opening metathesis polymerization (ROMP), with weight-average molecular weights given by this method closely correlated to those obtained from GPC measurement.

SUBMITTER: Li W

PROVIDER: S-EPMC3545650 | biostudies-literature | 2012 Dec

REPOSITORIES: biostudies-literature

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Application of (1)H DOSY for Facile Measurement of Polymer Molecular Weights.

Li Weibin W Chung Hoyong H Daeffler Christopher C Johnson Jeremiah A JA Grubbs Robert H RH

Macromolecules 20121204 24

To address the practical issues of polymer molecular weight determination, the first accurate polymer weight-average molecular weight determination method in diverse living/controlled polymerization via DOSY (diffusion-ordered NMR spectroscopy) is reported. Based on the linear correlation between the logarithm of diffusion coefficient (log D) and the molecular weights (log Mw), external calibration curves were created to give predictions of molecular weights of narrowly-dispersed polymers. This ...[more]

PMID: 23335819

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