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Updated: Jul 6, 2026
09:22
Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives
Published on: February 7, 2017
Kinetically driven helix formation during the homopolymer collapse process
Sid Ahmed Sabeur1, Fatima Hamdache, Friederike Schmid
1Département de Physique, Faculté des Sciences, USTO, Oran, Algeria.
Summary
Simple homopolymer chains in bad solvents spontaneously form helices when collapsing. This helix formation, driven by unstable modes, is enhanced when hydrodynamic interactions are screened.
Area of Science:
- Polymer Physics
- Computational Chemistry
- Soft Matter Physics
Background:
- Homopolymer chains in solution are fundamental models in polymer physics.
- Chain collapse in poor solvents is a critical phenomenon.
- Understanding conformational transitions is key to polymer behavior.
Purpose of the Study:
- To investigate the spontaneous formation of ordered structures in collapsing homopolymer chains.
- To identify the mechanisms driving helical order in generic bead-and-spring models.
- To explore the influence of solvent quality and hydrodynamic interactions on chain conformation.
Main Methods:
- Langevin dynamics simulations were employed to model polymer chain behavior.
- Generic bead-and-spring homopolymer models were utilized.
- Simulations explored chains collapsing from stretched conformations in poor solvents.
Main Results:
- Spontaneous helical order develops in collapsing homopolymer chains in poor solvents.
- Unstable modes of the straight chain initiate helix formation.
- A long-lived metastable transient state characterized by helical structure was observed.
- The helical ordering effect is amplified when hydrodynamic interactions are screened.
Conclusions:
- Generic homopolymer chains can spontaneously form helical structures during collapse in poor solvents.
- Chain dynamics and initial instabilities play a crucial role in driving ordered conformations.
- Screening of hydrodynamic interactions significantly enhances the observed helical ordering phenomenon.
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