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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
Single chain diffusion of poly(ethylene oxide) in its monolayers before and after crystallization
1Beijing Laboratory of Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
Langmuir : the ACS Journal of Surfaces and Colloids
|December 31, 2009
Summary
Poly(ethylene oxide) chain diffusion slows significantly after crystallization due to lower surface concentration. This impacts polymer crystallization under surface confinement.
Area of Science:
- Polymer science
- Surface science
- Materials science
Background:
- Polymer crystallization is influenced by chain mobility.
- Understanding diffusion in polymer monolayers is crucial for surface-confined crystallization.
Purpose of the Study:
- To investigate the lateral diffusion of poly(ethylene oxide) (PEO) chains during crystallization in monolayers on silica surfaces.
- To elucidate the relationship between PEO chain diffusion, surface concentration, and the crystallization process.
Main Methods:
- Single molecule fluorescence microscopy
- Single molecule tracking techniques
Main Results:
- PEO chain diffusion coefficients are significantly lower after crystallization compared to the supercooled state.
- Reduced diffusion correlates with decreased polymer surface concentration and monolayer thickness.
- Chains adopt a more flattened conformation and stronger surface adhesion at lower concentrations, reducing mobility.
Conclusions:
- Polymer crystallization under surface confinement is strongly influenced by mass transport dynamics.
- The crystallization process alters chain diffusion by changing surface concentration and chain conformation.
- This study highlights the interplay between crystallization and diffusion in confined polymer systems.
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