| Autor: |
Wang, H., Aubuchon, S. R., Thompson, D. G., Osborn, J. C., Marsh, A. L., Nichols, W. R., Schoonover, J. R., Palmer, R. A. |
| Zdroj: |
Macromolecules; November 2002, Vol. 35 Issue: 23 p8794-8801, 8p |
| Abstrakt: |
Variable temperature dynamic mechanical analysis (DMA) and Fourier transform infrared spectroscopy (FTIR) have been combined and applied to rheooptical (DMA-FTIR) studies of thin films of a poly(ester urethane). In this study, dynamic infrared linear dichroism (DIRLD) measurements have been carried out at 25, −5, and −30 °C with the step-scan FTIR modulation/demodulation technique. The changes in both the in-phase and quadrature spectra as a function of temperature reveal different responses for the various functional groups as a function of temperature. In particular, as the temperature is lowered, the dynamic responses of structurally different carbonyl groups (hydrogen-bonded, free, urethane, ester) are clearly differentiated. The changes in dynamic response are related to changes in the hydrogen-bonding interactions in this polymer as well as to distinction between different molecular-level microenvironments. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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