Reversible flocculation of silica across the phase boundary of poly(vinyl caprolactam) in aqueous solution
The colloid stability of silica dispersions in water in the presence of poly(vinyl caprolactam) (PVCAP) has been studied below and above the lower consolute temperature (LCT) of its solutions. The dispersion sediments slowly without PVCAP in the temperature range studied (26-40 degrees C) or with PV...
| Veröffentlicht in: | Langmuir : the ACS journal of surfaces and colloids. - 1992. - 21(2005), 26 vom: 20. Dez., Seite 12096-9 |
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| Weitere Verfasser: | , |
| Format: | Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2005
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| Zugriff auf das übergeordnete Werk: | Langmuir : the ACS journal of surfaces and colloids |
| Schlagworte: | Journal Article |
| Zusammenfassung: | The colloid stability of silica dispersions in water in the presence of poly(vinyl caprolactam) (PVCAP) has been studied below and above the lower consolute temperature (LCT) of its solutions. The dispersion sediments slowly without PVCAP in the temperature range studied (26-40 degrees C) or with PVCAP below the LCT ( approximately 30 degrees C). In contrast, with PVCAP above the LCT, rapid flocculation occurs at acid pH, with re-dispersal on cooling. Reversible flocculation is also obtained above the LCT by cycling the pH from alkaline to acid and back. The flocculation observed above the LCT may also be regarded as heterocoagulation between the silica particles and the aggregates of the polymer |
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| Beschreibung: | Date Completed 19.07.2007 Date Revised 13.12.2005 published: Print Citation Status PubMed-not-MEDLINE |
| ISSN: | 1520-5827 |