| Autor: |
Chen-Chi M. Ma, Albert Y. C. Hung, Feng-Yih Wang, Hew-Der Wu |
| Rok vydání: |
2003 |
| Předmět: |
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| Zdroj: |
European Polymer Journal. 39:225-231 |
| ISSN: |
0014-3057 |
| DOI: |
10.1016/s0014-3057(02)00230-6 |
| Popis: |
The effect of association reaction length on the substantial increase of molecular motion as well as entropy (−TΔSm) of phenolic–polyamide blends is investigated with the 13C solid-state NMR and DSC. The H-bonding strength by forming the phenolic–polyamide interaction is great enough to overcome the breaking off the self-association of phenolic. With respect to decreasing the association reaction, the polyamide resonance intensity of 13C solid-state NMR spectra is weakened due to the reduction of the cross-polarization efficiency at a high mobile sample. The glass transition temperature of phenolic–polyamide blend as well as TH1ρ value from NMR experiments is also decreased. The decreasing strength of H-bonding resulting from blending causes higher entropy (−TΔSm) and higher molecular mobility of the phenolic–polyamide blends. Accordingly, the polyamide-66 possesses higher H-bonding force and exhibits more mobile role in this phenolic/polyamide blends family. It can be concluded that the molecular segmental motion and entropy are progressively decreased while increasing the inter-association force of the polyamide within the miscible window. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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