| Autor: |
Göran Ström, Rauni Seppänen, J. Elftonson |
| Rok vydání: |
2000 |
| Předmět: |
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| Zdroj: |
Colloids and Surfaces A: Physicochemical and Engineering Aspects. 164:131-141 |
| ISSN: |
0927-7757 |
| DOI: |
10.1016/s0927-7757(99)00213-7 |
| Popis: |
Heteroflocculation studies of kaolin particles have been carried out by mixing two kaolin suspensions; one stabilised by a cationic polymer and the other stabilised by a highly charged and low molecular weight anionic polymer. Molar mass and charge density of cationic polymer as well as the mixing ratio of oppositely charged suspensions were varied. Floc size and degradation during shearing were investigated by measuring floc size using a light scattering/diffraction method at different flow rates. It was observed that floc size was small when subjected to a low flow rate and decreased with increasing flow rate. Cationic polymers with high molar mass and low charge density produced flocs with high resistance towards floc degradation. Maximum floc size was obtained at a mixing ratio where the flocs became slightly negatively charged. Floc size and degradation were observed to be independent of primary kaolin particle size. Furthermore, floc size increased with increasing ionic strength. Scanning electron micrographs showed flocs with an open structure, which is expected to improve the optical properties of paper when using microflocs as a filler in paper production. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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