Ageing of fibre-laden aqueous foams
Fibre-laden liquid foams are used in the production process of novel non-woven fibrous materials, employed for example for thermal or acoustic insulation. Here we present an experimental investigation of the stability of such foams. We find that on a time-scale of a few minutes the presence of fibres does not alter the drainage properties of the foam. On a longer time-scale fibres slow down drainage, mainly due to their slowing down of coarsening. The drying of our aged samples leads to a fibre network with a fibre concentration profile that appears to be determined by gravity. Our experiments were performed using fibre concentrations of a few percent, as relevant also to the foam-laid forming of paper, where aqueous foam instead of water is used as a carrier medium for fibres .
KeywordsFoam Paper-making Drainage Novel materials Foam ageing Foam stability Drainage simulation Fibre-laden foams production
We would like to thank T. Hjelt and J. Ketoja, both at VTT Espoo Finland, for many engaging discussions. This publication has emanated from research supported in part by a research grant from Science Foundation Ireland (SFI) (Grant no. 13/IA/1926). We also acknowledge the support of the MPNS COST Actions (European Cooperation in Science and Technology) MP1106 “Smart and green interfaces” and MP1305 “Flowing matter” and the European Space Agency ESA, Project microG-Foam, AO-99-075 and contract 4000115113, “Soft Matter Dynamics”. We thank project students M. McGrath and D. McDermott for some experimental contributions to this work.
- Abràmoff MD, Magalhães PJ, Ram SJ (2004) Image processing with ImageJ. Biophoton Int 11(7):36–42Google Scholar
- Haffner B, Dunne F, McDermott D, Hutzler S (2016) Analysis of controlled free drainage experiments of aqueous foams (to be submitted in 2016)Google Scholar
- Weaire D, Hutzler S (2001) The physics of foams. Oxford University Press, OxfordGoogle Scholar
- Whyte D, Haffner B, Tanaka A, Hjelt T, Hutzler S (2016) The interactions of fibres with soap films (to be submitted in 2016)Google Scholar