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Updated: Jul 14, 2025
09:32
Cooling Rate Dependent Ellipsometry Measurements to Determine the Dynamics of Thin Glassy Films
Published on: January 26, 2016
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Anisotropic material depletion in epitaxial polymer crystallization.
Jason X Liu1,2, Yang Xia1, Yucheng Wang3
1Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544, USA.
Soft Matter
|October 9, 2023
Summary
Researchers explored edge-on crystallization in semicrystalline polymer thin films. Using epitaxial growth and matrix-assisted pulsed laser evaporation (MAPLE), they revealed anisotropic material depletion during this process.
Area of Science:
- Materials Science
- Polymer Physics
- Surface Science
Background:
- Semicrystalline polymer thin film properties depend on crystalline domain morphology.
- Mechanisms of flat-on polymer crystal orientation are understood, but edge-on orientation mechanisms are not.
- Thin films tend to adopt flat-on orientations, complicating edge-on studies.
Purpose of the Study:
- To investigate the elusive mechanisms of edge-on crystallization in polymer thin films.
- To enforce edge-on orientation using an epitaxial polymer-substrate relationship.
- To understand the physics of polymer crystallization under confinement.
Main Methods:
- Employing an epitaxial polymer-substrate relationship to direct crystallization.
- Utilizing matrix-assisted pulsed laser evaporation (MAPLE) for film deposition.
- Combining experimental results with phase-field simulations.
Main Results:
- Successfully enforced edge-on crystallization in thin polymer films.
- Demonstrated spatially separated crystal nucleation and epitaxial crystallization.
- Observed highly anisotropic and localized material depletion during edge-on crystallization.
Conclusions:
- Provided deeper insight into the physics of polymer crystallization under confinement.
- Introduced a novel processing motif for the crystallization of ultrathin structured films.
- Advanced the understanding of structure-property relationships in polymer thin films.
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