Foldamer Architectures of Triazine-Based Sequence-Defined Polymers Investigated with Molecular Dynamics Simulations...

Area of Science:

• Materials Science
• Polymer Chemistry
• Computational Chemistry

Background:

• Recently developed triazine-based sequence-defined polymers are biomimetic and robust.
• These polymers exhibit self-assembly into linear nanorod foldamers via hydrogen bonding and π-π interactions.
• Nanorod foldamers possess structural motifs similar to DNA, α-helices, and β-sheets, indicating potential as macromolecular building blocks.

Purpose of the Study:

• To investigate the influence of linker structures on the folding of triazine-based polymers into nanorod foldamers.
• To explore the formation and diversity of foldamers in longer polymer chains (octamers and decamers) using advanced simulation techniques.

Main Methods:

• Molecular dynamics (MD) simulations were employed to study polymer folding.
• Concurrent adaptive sampling (CAS) and replica exchange molecular dynamics (REMD) were utilized for enhanced sampling of longer polymers.
• Analysis focused on the role of specific linker chemistries and polymer lengths in foldamer formation.

Main Results:

• Specific linker structures, such as pentanediamine and *ortho*-xylenediamine, were found to be favorable for hexamer folding.
• Enhanced sampling methods (CAS and REMD) successfully induced foldamer formation in longer polymers where standard MD failed.
• REMD simulations identified novel foldamer architectures, including those resulting from *cis-trans* isomerizations.

Conclusions:

• Linker structure and polymer length are critical factors governing the formation and architecture of triazine-based nanorod foldamers.
• Enhanced sampling techniques are essential for observing foldamer formation in longer synthetic polymer chains.
• The study provides valuable insights into the diversity of foldamer architectures and the capabilities of simulation methods for designing new biomimetic materials.