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Synthesis of Monodisperse Cylindrical Nanoparticles via Crystallization-driven Self-assembly of Biodegradable Block Copolymers
Published on: June 20, 2019
Self-assembling semicrystalline polymer into highly ordered, microscopic concentric rings by evaporation.
Myunghwan Byun1, Suck Won Hong, Lei Zhu
1Department of Materials Science and Engineering, Iowa State University, Ames, Iowa 50011, USA.
Langmuir : the ACS Journal of Surfaces and Colloids
|February 16, 2008
Summary
Researchers created ordered poly(ethylene oxide) (PEO) rings using controlled solvent evaporation. These PEO rings exhibit unique surface morphology and crystallization patterns, offering potential for biological applications.
Area of Science:
- Polymer Science
- Materials Science
- Surface Chemistry
Background:
- Controlled self-assembly of polymers is crucial for advanced material design.
- Understanding polymer crystallization in confined geometries informs material properties.
- Poly(ethylene oxide) (PEO) is a versatile semicrystalline polymer with various applications.
Purpose of the Study:
- To investigate the formation of microscopic concentric rings of poly(ethylene oxide) (PEO) via solvent evaporation in a sphere-on-flat geometry.
- To characterize the surface morphology and crystallization behavior of these PEO rings.
- To explore the potential of these ordered PEO structures as platforms for biological studies.
Main Methods:
- Sphere-on-flat geometry utilized for controlled solvent evaporation.
- Microscopic observation of ring formation driven by contact line pinning-depinning cycles.
- Atomic Force Microscopy (AFM) used to analyze surface morphology and crystallization.
- Isothermal crystallization experiments conducted at 40 and 58 degrees C.
Main Results:
- Microscopic concentric rings of high molecular weight PEO were successfully produced.
- Evaporation-induced PEO rings displayed a fibrillar-like surface morphology.
- Isothermal crystallization resulted in multilayer flat-on lamellae with spiral morphology.
- Depletion zones were observed between adjacent spirals during crystallization.
Conclusions:
- Controlled solvent evaporation in a sphere-on-flat geometry yields highly ordered, concentric PEO rings.
- The resulting PEO structures possess unique morphologies and crystallization patterns.
- These ordered PEO rings show promise as substrates for studying cell adhesion, motility, and mechanotransduction.
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