High-resolution 13C–nuclear magnetic resonance study of heterogeneous amorphous polymers
✍ Scribed by Maria Inês Bruno Tavares
- Publisher
- John Wiley and Sons
- Year
- 2002
- Tongue
- English
- Weight
- 65 KB
- Volume
- 87
- Category
- Article
- ISSN
- 0021-8995
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✦ Synopsis
Abstract
The combination of solid‐state nuclear magnetic resonance (NMR) techniques is very helpful for examining the behavior of heterogeneous amorphous polymers. With the magic‐angle spinning (MAS) technique, employing special conditions, only the mobile fraction of the molecule can be assigned. Cross‐polarization magic‐angle spinning (CPMAS) permits the evaluation of changes in the NMR line shapes and chemical shifts. The employment of proton spin‐lattice relaxation times (T~1~ and T~1~ρ) gives useful information on the molecular dynamic in heterogeneous polymers. From these parameters the response of the molecular mobility behavior of the polymer chains can be obtained. The results of the present work are discussed in this article in terms of molecular mobility and domain formations of heterogeneous amorphous polymers in order to understand the relations in the structure–mobility property. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 473–476, 2003
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