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Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives
Published on: February 7, 2017
Helical dendronized polymers with chiral second-generation dendrons: atomistic view and driving forces for structure
Francisco Rodríguez-Ropero1, Manel Canales, David Zanuy
1Departament d'Enginyeria Química, Universitat Politècnica de Catalunya, Diagonal 647, Barcelona E-08028, Spain.
The Journal of Physical Chemistry. B
|October 20, 2009
Summary
Protected and charged dendronized polymers exhibit a right-handed helical structure. Interdendron interactions, particularly hydrogen bonds in protected polymers, dictate secondary structure, rigidity, and thermal stability.
Area of Science:
- Polymer Chemistry
- Computational Materials Science
Background:
- Dendronized polymers offer unique structural and functional properties.
- Understanding the secondary structure of these complex macromolecules is crucial for their applications.
Purpose of the Study:
- To investigate the secondary structures of protected and deprotected dendronized polymethylmethacrylates.
- To correlate structural parameters, rigidity, and thermal stability with microscopic interactions.
Main Methods:
- Atomistic molecular dynamics simulations were employed.
- Simulations covered approximately 280 ns on systems with up to 101,909 explicit particles.
Main Results:
- Both neutral and charged polymers adopt a right-handed helical secondary structure.
- Helical structure is enforced by dendron packing, leading to similar backbone arrangements.
- Interdendron hydrogen bonds in protected polymers contribute to thermal stability and rigid rod-like behavior.
- Charged polymers exhibit specific side-chain arrangements to minimize charge repulsion.
Conclusions:
- Secondary structure and properties are governed by interdendron interactions.
- The helical conformation is a stable feature across neutral and charged states.
- Conformational changes upon deprotection were successfully evaluated.
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