Fluorescence anisotropy measurements on a polymer melt as a function of applied shear stress
| Autor: | Francis W. Wang, Charles L. Thomas, Anthony J. Bur, Robert E. Lowry, Steven C. Roth |
|---|---|
| Rok vydání: | 1992 |
| Předmět: |
Polymers and Plastics
Chemistry Organic Chemistry Analytical chemistry Pure shear Condensed Matter::Soft Condensed Matter Inorganic Chemistry Shear modulus Shear rate Shear (geology) Critical resolved shear stress Materials Chemistry Shear stress Composite material Anisotropy Fluorescence anisotropy |
| Zdroj: | Macromolecules. 25:3503-3510 |
| ISSN: | 1520-5835 0024-9297 |
| DOI: | 10.1021/ma00039a031 |
| Popis: | Steady-state fluorescence anisotropy measurements were carried out under zero shear and under finite shear conditions over a shear rate range for which the specimen displayed non-New-tonian behavior, 2.64×10 -3 to 5.3 s -1 . Anisotropy was observed to decrease with increasing applied shear stress. The magnitude of the effect is small and is attributed to shear-induced orientation of the anthracene-tagged polybutadiene molecule which is engaged in the entanglement network of the host PB. Diluting the entanglement network using plasticizer produced a smaller effect. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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