Abstract
Synopsis A method for measuring the variation of electrical impedance (Z) of thin layers (0.1 mm) of O/W emulsions during evaporation in a controlled environment is presented. The evaporation of an emulsion base (A) either as such and containing 1% glycerin (B) or 1% sodium pyrrolidonecarboxylate (C) was investigated for 120 min at constant air temperature (25 degrees C) and relative humidity (55%). The measured impedance of the emulsion layers increased by three orders of magnitude during the evaporation cycles. The relationship between impedance and water content of the evaporating emulsion layers was investigated. Each emulsion showed a complex linear relationship between log Z and water content, the relationship being represented by two (three, for emulsion A) linear portions in the graph. Plots of water content vs. time, temperature vs. time and rate of water loss vs. water content of the emulsion layers are presented. The data appear to indicate that evaporation proceeds via distinct stages, whose correspondence to different mechanisms of water evaporation is discussed. The potentiality of the present method for water analysis, and for investigating structural changes in emulsions during evaporation, is also discussed.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
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.