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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
Block-copolymer ordering with a spatiotemporally heterogeneous mobility
August W Bosse1, Jack F Douglas, Brian C Berry
1Polymers Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8541, USA.
Physical Review Letters
|February 1, 2008
Summary
Block-copolymer ordering is influenced by spatially varying mobility, impacting microdomain structure. Nanoscale dynamics in glass formation affect the final block-copolymer microphase structure.
Area of Science:
- Materials Science
- Polymer Physics
- Soft Matter Physics
Background:
- Block-copolymer films exhibit stripe-forming morphologies.
- Zone annealing measurements reveal influences on ordering.
- Material properties like mobility can be spatially and temporally dependent.
Purpose of the Study:
- To investigate the effect of spatiotemporally heterogeneous mobility on block-copolymer ordering.
- To model block-copolymer ordering using self-consistent field theory with a dynamic mobility field.
- To understand the impact of nanoscale dynamic heterogeneities on microphase structure.
Main Methods:
- Implementation of a time- and space-dependent mobility field within diblock copolymer self-consistent field theory.
- Inclusion of a mobility gradient and nanoscale mobility variations characteristic of glass phenomenology.
- Computational simulations to observe microdomain ordering.
Main Results:
- Spatiotemporally heterogeneous mobility significantly influences microdomain ordering in block-copolymer systems.
- Nanoscale dynamic heterogeneities, typical of glass formation, impact the ordered block-copolymer microphase structure.
- Simulations demonstrate a clear correlation between mobility variations and resulting film morphology.
Conclusions:
- Heterogeneous mobility is a critical factor controlling block-copolymer self-assembly.
- Understanding nanoscale dynamics is essential for predicting and controlling block-copolymer structures.
- This work provides insights into directed self-assembly processes for nanostructure fabrication.
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