Abstract

Abstract Alkane vapours adsorb onto surfactant monolayers at the air–water surface to form mixed alkane–surfactant films. We have determined the effects of alkane vapours on the foamability and foam stability for aqueous foams stabilised by non-ionic alkyl ethoxylate surfactants of different head and tail chain lengths. Foamability was determined by measuring the volume of foam generated by bubbling nitrogen gas, with and without oil vapour, through the surfactant solution as a function of surfactant concentration. In the absence of oil vapour, the surfactant concentration C 1/2 (corresponding to the transition from non-foaming to foaming behaviour) is less than the critical micelle concentration (cmc) for short chain surfactants and greater than the cmc for long chain surfactants. The addition of alkane vapours within the gas stream during foam formation increases C 1/2 to concentrations in excess of the cmc, i.e. oil vapours inhibit foamability. In addition to the effects on foamability, oil vapours also accelerate the decay rates of foams derived from plots of foam volume versus time.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.