Coarse-Grained Models for Simulations of Conformational Properties of Three-Dimensional Ladder Polymers in Solutions
1School of Materials and Environmental Engineering, Hunan University of Humanities, Science and Technology, Loudi, Hunan417000, P. R. China.
The Journal of Physical Chemistry. B
|April 18, 2026
Summary
Newly developed ladder polymers show promise for gas separation membranes. Molecular dynamics simulations reveal distinct chain shapes and scaling behaviors, guiding membrane design.
Area of Science:
- Polymer Science
- Materials Science
- Computational Chemistry
Background:
- Three-dimensional ladder polymers are advanced membrane materials for gas separations.
- Experimental characterization of their solution conformational properties is challenging.
- Molecular simulations offer a complementary approach to understand polymer behavior.
Purpose of the Study:
- To develop and validate coarse-grained models for ladder polymers and their solvent.
- To investigate the conformational properties of ladder polymers using molecular dynamics simulations.
- To elucidate the relationship between polymer structure, solvent effects, and gas separation performance.
Main Methods:
- Parametrization of coarse-grained (CG) models for ladder polymers and chloroform using bottom-up and top-down schemes.
- Conducting CG molecular dynamics (MD) simulations at equivalent high temperatures for syn and anti configurations.
- Analyzing polymer chain shapes, end-to-end distance (Re), and radius of gyration (Rg) in vacuum and solution.
Main Results:
- CG models demonstrate good structural representability and temperature transferability.
- Syn chains adopt a spring-like shape, while anti-chains exhibit an open, straight conformation with increasing polymerization.
- Scaling relations for Re and Rg were identified for anti-chains in vacuum, and for Re of syn-chains in solution, highlighting solvent influence.
Conclusions:
- The study successfully developed transferable CG models for ladder polymer simulations.
- Distinct conformational behaviors of syn and anti ladder polymers were revealed, influenced by chain rigidity and solvent interactions.
- Findings provide valuable insights for designing efficient ladder polymer membranes for gas separations.
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