Water Soluble Rigid Rod Polymers: A SANS Study of Shear-Induced Alignment and Relaxation
| Autor: | Stephen J. Picken, Eduardo Mendes, Ourides Santin, Sebastien Viale |
|---|---|
| Rok vydání: | 2004 |
| Předmět: |
chemistry.chemical_classification
Materials science Scattering Isotropy General Chemistry Polymer Condensed Matter Physics Small-angle neutron scattering Rod Physics::Fluid Dynamics Condensed Matter::Soft Condensed Matter Crystallography chemistry Deuterium Shear (geology) Perpendicular General Materials Science Composite material |
| Zdroj: | Molecular Crystals and Liquid Crystals. 411:525-535 |
| ISSN: | 1563-5287 1542-1406 |
| DOI: | 10.1080/15421400490436449 |
| Popis: | In this paper, we report the effect of shear and relaxation on low concentration solutions of a synthetic water-soluble rigid rod polymer in deuterated water using small angle neutron scattering (SANS). The polymer used is sulfo poly p-phenyleneterephtalamide (Sulfo-PPTA). At rest, a 1wt% solution of Sulfo-PPTA presents a scattering maximum at small angles that is related to the interaction between rods. Under the action of very small shear rates, a high alignment is observed. The scattering maximum, initially isotropic, strongly increases upon shear in the direction perpendicular to the applied shear while it is suppressed in the direction parallel to the shear. After cessation of shear the alignment remains for a considerable period of time. The ?P2? order parameter has been determined from the SANS data during application of shear and during relaxation. The formation of needle-like aggregates in solution is suggested as a possible explanation of our results. |
| Databáze: | OpenAIRE |
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