Abstract
Fluorescent whitening agents (FWA) are used to improve the whiteness of cellulose fabrics. It is well known but not completely understood that the fluorescence decreases (chemical and physical mechanisms of distinguishing) above a certain FWA concentration ccrit. This reduction of fluorescence correlates very well with the alteration of the adsorption process studied by calorimetry and zeta potential measurements. The results obtained by these methods indicate that the adsorption mechanism is different at concentrations below and above ccrit. The reduction of the intensity of fluorescence, the degree of whiteness and the zeta potential are caused by the adsorption of a second layer of fluorescent whitening agents. This second layer reduces the zeta potential due to a shielding effect and reduces the whiteness and fluorescence by a bathochromic shift of the reflection curves. The final effect is a reduction of the total reflection.
| Original language | English |
|---|---|
| Pages (from-to) | 1174-1178 |
| Number of pages | 5 |
| Journal | Colloid & Polymer Science |
| Volume | 273 |
| Issue number | 12 |
| DOIs | |
| Publication status | Published - 1 Dec 1995 |
| Externally published | Yes |
Keywords
- adsorption
- calorimetry
- Cotton fibers
- degree of whiteness
- dye
- fluorescence
- zeta potential
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Polymers and Plastics
- Colloid and Surface Chemistry
- Materials Chemistry