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Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
Mesoscopic patterning in evaporated polymer solutions: new experimental data and physical mechanisms
Edward Bormashenko1, Roman Pogreb, Oleg Stanevsky
1The Research Institute, The College of Judea and Samaria, 44837 Ariel, Israel. Edward@yosh.ac.il
Langmuir : the ACS Journal of Surfaces and Colloids
|October 7, 2005
Summary
Polymer solutions on tilted surfaces form ordered patterns during rapid solvent evaporation. This phenomenon, driven by mass transport instability, is influenced by polymer concentration and substrate properties.
Area of Science:
- Materials Science
- Physical Chemistry
- Fluid Dynamics
Background:
- Ordered patterns are crucial in materials science for various applications.
- Understanding pattern formation during solvent evaporation is key to controlling material properties.
Purpose of the Study:
- To investigate the formation of mesoscopically ordered patterns from polymer solutions under specific evaporation conditions.
- To elucidate the physical mechanism driving this pattern formation process.
Main Methods:
- Applying polymer solutions to tilted substrates followed by immediate evaporation under ambient conditions with controlled airflow.
- Utilizing optical microscopy, scanning electron microscopy (SEM), and atomic force microscopy (AFM) for pattern characterization.
- Employing shadowgraph visualization and ink tracer methods to study fluid flow dynamics.
Main Results:
- Mesoscopically ordered patterns were successfully generated under the described conditions.
- Both restrained and nonrestrained flows of the polymer solution resulted in similar patterning.
- The concentration of polymer solutions was found to influence the characteristic dimensions of the mesoscaled cells.
- Pattern formation was observed on various substrates, including those treated with silicon oil.
Conclusions:
- A physical mechanism involving mass transport instability during intensive solvent evaporation is proposed.
- The proposed mechanism adequately explains the observed experimental findings related to pattern formation.
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