Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9675768 | Colloids and Surfaces A: Physicochemical and Engineering Aspects | 2005 | 6 Pages |
Abstract
The foamability of polypropylene glycol (PPG) surfactants was investigated as a function of PPG concentration and molecular weight and compared with their surface activity. It was found that foamability increases with the amount of PPG adsorbed at the air-water interface up to monolayer coverage, but decreases at high concentrations due to the formation of PPG droplets, which destabilise the foam. Although high molecular weight PPGs have higher surface activity, foamability decreases with increasing PPG molecular weight because of their slower diffusion to, or at the air-water interface. The effect of the hydrophobicity or polarity of the end groups of PPG on foamability was also investigated, and it was found that foamability increases only if the PPG molecule is charged. The presence of salt destabilises the PPG foams.
Related Topics
Physical Sciences and Engineering
Chemical Engineering
Colloid and Surface Chemistry
Authors
Su Nee Tan, Daniel Fornasiero, Rossen Sedev, John Ralston,