[article]
Titre : |
Dispersing without destroying |
Type de document : |
texte imprimé |
Auteurs : |
Hans Joachim Jacob, Auteur |
Année de publication : |
2019 |
Article en page(s) : |
p. 34-37 |
Langues : |
Anglais (eng) |
Catégories : |
Dispersions et suspensions Expansion sous vide hydrocolloïdes Rhéologie
|
Index. décimale : |
660.2 Génie chimique |
Résumé : |
In home and personal care products, many hydrocolloids are used as thickeners and rheological additives. When mixed into liquids, initially agglomerates are created, vvhich then have to be broken dovvn again through dispersing. However, most of these polymers are shear sensitive, especially after hydration. Dispersing destroys the gel structure already formed and breaks down the desired viscosity. This problem can be solved with a process that separates the primary particles of the polymer powder before they get in contact with the liquid, then individually wets and disperses them immediately, thereby hydrating them without agglomerates — using the vacuum-expansions process. It is based on the fact that a powerful vacuum is generated directly in the liquid. The polymer is therefore added under maximum vacuum. In this way, the polymer particles are dissagglomerated before wetting. No further dispersion is required. Agglomerates are not created. Using the vacuum expansion process, the maximum effect can be achieved with a reduced concentration of hydrocolloids. Viscosity, thixotropy index, transparency, film formation and wetting behaviour, as well as many other properties this way will achieve a level not possible previously A subsequent uncontrolled thickening through inorganic thickeners, such as smectite or other layered mineral silicates is ruled out. |
Note de contenu : |
- Functionality must be ensured
- Agglomerates have to be prevented
- Shearing may cause irreversible damage
- This is how the vacuum expansion method with the conti-TDS works
- Wetting from inside
- Fig. 1 : Vacuum-expansions process
- Fig. 2 : Disintegration of agglomerates under vacuum expansion
- Fig. 3 : Integration of Conti-TDS into existing or new plants |
Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=32730 |
in SOFW JOURNAL > Vol. 145, N° 5 (05/2019) . - p. 34-37
[article]
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