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Molecular simulation of polymer crystallization under chain and space confinement
Yongqiang Ming1, Zhiping Zhou, Tongfan Hao
1Research School of Polymeric Materials, School of Materials Science and Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013, China. haotf@ujs.edu.cn nieyijing@ujs.edu.cn.
Physical Chemistry Chemical Physics : PCCP
|August 5, 2021
Summary
Polymer crystallization is enhanced by increased free chain content and larger system sizes under confinement. Simulations reveal tethering points act as nucleation sites, impacting polymer crystallization kinetics.
Area of Science:
- Polymer Science
- Materials Science
- Computational Chemistry
Background:
- Polymer crystallization is influenced by confinement effects.
- Understanding these effects is crucial for material properties.
Purpose of the Study:
- To investigate polymer crystallization under chain and space confinements using Monte Carlo simulations.
- To explore the impact of free chain content and lateral size on crystallinity and melting temperature.
Main Methods:
- Monte Carlo simulation of polymer crystallization.
- Analysis of crystallinity, melting temperature, surface free energy, and diffusion activation energy.
Main Results:
- Crystallinity and melting temperature increase with higher free chain content and larger lateral system sizes.
- Tethering points confirmed as nucleation sites, a phenomenon difficult to observe experimentally.
- Nucleation ability is enhanced in smaller lateral systems (8 lattice points) with increased free chain content.
- Larger lateral systems (12 lattice points) show decreased nucleation sites and increased energy barriers with higher free chain content.
- Interfacial interactions significantly alter confined polymer crystallization.
Conclusions:
- Simulation results align with experimental findings on confined polymer crystallization.
- Provides microscopic insights into crystallization kinetics, revealing the role of nucleation sites and chain dynamics.
- Highlights the complex interplay between confinement dimensions, chain mobility, and interfacial effects on polymer crystallization.
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