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arXiv · 2211.16954

The evaporation of concentrated polymer solutions is insensitive to relative humidity

Max Huisman·Paul Digard·Wilson C. K. Poon·Simon Titmuss
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Abstract

A recent theory suggests that the evaporation kinetics of macromolecular solutions is insensitive to the ambient relative humidity (RH) due to the formation of a `polarisation layer' of solutes at the air-solution interface. We confirm this insensitivity up to RH~80% in the evaporation of polyvinyl alcohol solutions from open-ended capillaries. To explain the observed drop in evaporation rate at higher RH, we need to invoke compressive stresses due to interfacial polymer gelation. Moreover, RH-insensitive evaporation sets in earlier than theory predicts, suggesting a further role for a gelled `skin'. We discuss the relevance of these observations for respiratory virus transmission via aerosols.

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Max Huisman, Paul Digard, Wilson C. K. Poon, Simon Titmuss. 2022-11-30. The evaporation of concentrated polymer solutions is insensitive to relative humidity. https://arxiv.org/abs/2211.16954

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