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Synthesis of Monodisperse Cylindrical Nanoparticles via Crystallization-driven Self-assembly of Biodegradable Block Copolymers
Published on: June 20, 2019
Nucleation of ordered phases in block copolymers
Xiuyuan Cheng1, Ling Lin, Weinan E
1School of Mathematical Sciences and The Key Laboratory of Mathematics and Applied Mathematics, Peking University, Beijing 100871, China.
Physical Review Letters
|May 21, 2010
Summary
This study explores block copolymer phase nucleation using self-consistent field theory. It reveals distinct pathways for gyroid nucleus formation, including a novel intermediate structure.
Area of Science:
- Polymer Science
- Materials Science
- Computational Chemistry
Background:
- Block copolymers self-assemble into diverse ordered nanostructures.
- Understanding phase transitions is crucial for controlling material properties.
- Nucleation mechanisms dictate the final morphology and stability.
Purpose of the Study:
- To investigate the free-energy landscape of nucleation in block copolymers.
- To compute the minimum energy path (MEP) for phase transitions.
- To characterize the critical nuclei and their formation pathways.
Main Methods:
- Employing self-consistent field theory (SCFT) to model the system.
- Utilizing a recently developed string method to calculate the MEP.
- Analyzing the shape, size, and free-energy barriers of critical nuclei.
Main Results:
- The MEP provides insights into the emergence of stable phases from metastable ones.
- Two distinct MEPs were identified for the structural evolution of gyroid nuclei.
- An intermediate perforated layered structure was predicted during the transition pathway.
Conclusions:
- The study elucidates the complex nucleation pathways in block copolymers.
- The findings offer a deeper understanding of phase transitions and morphology control.
- The predicted transition pathway provides a roadmap for designing novel copolymer structures.
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