Elucidation of the Chain Conformation in a Glassy Polyester, PET, by Two-Dimensional NMR
10.1126/science.280.5364.714
Crossref journal-article
American Association for the Advancement of Science (AAAS)
Science (221)
Abstract

The chain conformation of glassy poly(ethylene terephthalate) (PET) was characterized by two-dimensional double-quantum nuclear magnetic resonance (NMR). In amorphous carbon-13–labeled PET, the statistics of the O– 13 CH 2 – 13 CH 2 –O torsion angle were determined, on the basis of the distinct shapes of the two-dimensional NMR patterns of trans and gauche conformations. In crystalline PET, the trans content is 100 percent, but in the amorphous PET it is only 14 percent (±5 percent). An average gauche torsion angle of 70 degrees (±9 degrees) was obtained. Implications for materials properties of polyesters are discussed.

Bibliography

Schmidt-Rohr, K., Hu, W., & Zumbulyadis, N. (1998). Elucidation of the Chain Conformation in a Glassy Polyester, PET, by Two-Dimensional NMR. Science, 280(5364), 714–717.

Authors 3
  1. K. Schmidt-Rohr (first)
  2. W. Hu (additional)
  3. N. Zumbulyadis (additional)
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  36. Generous financial support for K.S.-R. by a Beckman Young Investigator Award is gratefully acknowledged. Partial support was also provided by the NSF Materials Research Science and Engineering Center and by NSF grant DMR-9703916. K.S.-R. thanks M. Hong for stimulating discussions on data quantification.
Dates
Type When
Created 23 years, 1 month ago (July 27, 2002, 5:37 a.m.)
Deposited 1 year, 7 months ago (Jan. 13, 2024, 12:15 a.m.)
Indexed 2 months ago (July 1, 2025, 2:25 p.m.)
Issued 27 years, 4 months ago (May 1, 1998)
Published 27 years, 4 months ago (May 1, 1998)
Published Print 27 years, 4 months ago (May 1, 1998)
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@article{Schmidt_Rohr_1998, title={Elucidation of the Chain Conformation in a Glassy Polyester, PET, by Two-Dimensional NMR}, volume={280}, ISSN={1095-9203}, url={http://dx.doi.org/10.1126/science.280.5364.714}, DOI={10.1126/science.280.5364.714}, number={5364}, journal={Science}, publisher={American Association for the Advancement of Science (AAAS)}, author={Schmidt-Rohr, K. and Hu, W. and Zumbulyadis, N.}, year={1998}, month=may, pages={714–717} }