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Physical ageing of spreading droplets in a viscous ambient phase.

ABSTRACT: In this work, we study the spontaneous spreading of water droplets immersed in oil and report an unexpectedly slow kinetic regime not described by previous spreading models. We can quantitatively describe the observed regime crossover and spreading rate in the late kinetic regime with an analytical model considering the presence of periodic metastable states induced by nanoscale topographic features (characteristic area ~4 nm², height ~1 nm) observed via atomic force microscopy. The analytical model proposed in this work reveals that certain combinations of droplet volume and nanoscale topographic parameters can significantly hinder or promote wetting processes such as spreading, wicking, and imbibition.

SUBMITTER: Jose BM

PROVIDER: S-EPMC6155009 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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Physical ageing of spreading droplets in a viscous ambient phase.

Jose Bibin M BM Nandyala Dhiraj D Cubaud Thomas T Colosqui Carlos E CE

Scientific reports 20180921 1

In this work, we study the spontaneous spreading of water droplets immersed in oil and report an unexpectedly slow kinetic regime not described by previous spreading models. We can quantitatively describe the observed regime crossover and spreading rate in the late kinetic regime with an analytical model considering the presence of periodic metastable states induced by nanoscale topographic features (characteristic area ~4 nm<sup>2</sup>, height ~1 nm) observed via atomic force microscopy. The a ...[more]

PMID: 30242177

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