Microstructure of Poly(lactide). Phase-Sensitive HETCOR Spectra of Poly(meso-lactide), Poly(rac-lactide), and Atactic Poly(lactide)

Malcolm H. Chisholm, Suri S. Iyer, David G. McCollum, Mark "Marty" Pagel, Ulrike Werner-Zwanziger

Research output: Contribution to journalArticle

Abstract

We report the synthesis and 1H, 13C{1H}, and phase-sensitive HETCOR NMR spectra of atactic poly(lactide), poly(meso-lactide) and poly(rac-lactide). The new and existing spectroscopic data are discussed in terms of four alternative explanations: (i) Kricheldorfs tetrad assignments with the presumption that the adjacent chiral units exert an asymmetric influence on chemical shifts which is propagated in opposite directions along the polymer chain for 1H and 13C nuclei, respectively, (ii) alternative tetrad assignments we have recently proposed, (iii) assignments based on pentad stereosequences, and (iv) assignments based on the observation of triad and pentad stereosequences rather than tetrads. We show that the available data are insufficient to unequivocally distinguish between explanations i or iv.

Original languageEnglish (US)
JournalMacromolecules
Volume32
Issue number4
StatePublished - Feb 23 1999
Externally publishedYes

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Chemical shift
Nuclear magnetic resonance
Microstructure
Polymers
poly(lactide)
Direction compound

ASJC Scopus subject areas

  • Materials Chemistry

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Microstructure of Poly(lactide). Phase-Sensitive HETCOR Spectra of Poly(meso-lactide), Poly(rac-lactide), and Atactic Poly(lactide). / Chisholm, Malcolm H.; Iyer, Suri S.; McCollum, David G.; Pagel, Mark "Marty"; Werner-Zwanziger, Ulrike.

In: Macromolecules, Vol. 32, No. 4, 23.02.1999.

Research output: Contribution to journalArticle

Chisholm, Malcolm H. ; Iyer, Suri S. ; McCollum, David G. ; Pagel, Mark "Marty" ; Werner-Zwanziger, Ulrike. / Microstructure of Poly(lactide). Phase-Sensitive HETCOR Spectra of Poly(meso-lactide), Poly(rac-lactide), and Atactic Poly(lactide). In: Macromolecules. 1999 ; Vol. 32, No. 4.
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