## Abstract The absorption spectra of a series of polyamic acids prepared using various reaction conditions were studied using the ultraviolet (UV), visible, and near‐infrared (IR) ranges. The near‐IR proved most valuable; the amidization and imidization processes could be followed by observing the
The near-infrared spectra of polymers
✍ Scribed by Elbert W. Crandall; Ashvin N. Jagtap
- Publisher
- John Wiley and Sons
- Year
- 1977
- Tongue
- English
- Weight
- 323 KB
- Volume
- 21
- Category
- Article
- ISSN
- 0021-8995
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
A series of step reaction polymers have been prepared and studied as melt films or in solution in the overtone region and the combination region of the near‐IR. Systems containing aryl rings show bands in the 2.13‐ to 2.16‐μm region which are not observed in those systems not having aryl rings. Polyester, polyamide, and urea‐formaldehyde polymers show carbonyl, hydroxyl, and NH overtones. Polyurethanes show only the intense band of NH, in the 2.0‐ to 2.1‐μm region. Ureaformaldehyde and polyamides show this same band. Relative band intensities were compared to the first overtone of CH which appears at 1.67–1.72 μm. In this way, polymers can be compared in a quantitative manner, both with respect to reaction conditions and effect of heat curing.
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