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Published on: August 18, 2018
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Transient surface patterns during adhesion and coalescence of thin liquid films
Hongbo Zeng1, Boxin Zhao1, Yu Tian2
1Department of Chemical Engineering, Materials Department and Materials Research Laboratory, University of California, Santa Barbara, CA 93106, USA. jacob@engineering.ucsb.edu.
Soft Matter
|July 19, 2020
Summary
Transient surface ripple patterns emerge during polymer melt film coalescence, challenging traditional smooth deformation models. These patterns
Area of Science:
- Polymer Physics
- Surface Science
- Fluid Dynamics
Background:
- Liquid-liquid coalescence typically involves smooth surface deformations.
- Understanding polymer melt behavior is crucial for material processing and applications.
Purpose of the Study:
- To investigate surface deformations during polymer melt film coalescence.
- To identify and characterize transient patterns formed during coalescence.
Main Methods:
- Utilized a Surface Forces Apparatus (SFA) to study polymer melt film coalescence.
- Observed and analyzed surface deformations using in-situ visualization.
Main Results:
- Discovered well-ordered, periodic surface ripple/finger patterns during polymer melt coalescence.
- Pattern lifetimes were found to depend on polymer melt viscosity and film thickness.
- Observed patterns disappeared, resulting in smooth polymer-air interfaces.
Conclusions:
- Coalescence of polymer melts can exhibit complex transient surface patterns, deviating from smooth deformation models.
- These findings offer new insights into liquid-liquid adhesion and coalescence mechanisms.
- The phenomenon may be relevant to various microscopic and macroscopic systems.
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