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Updated: Jun 30, 2025
16:24
Controlling the Size, Shape and Stability of Supramolecular Polymers in Water
Published on: August 2, 2012
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Entropy Drives Interpolymer Association in Water: Insights into Molecular Mechanisms
Tobias Benselfelt1, Goksu Cinar Ciftci1, Lars Wågberg1
1Department of Fibre and Polymer Technology, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, 100 44 Stockholm, Sweden.
Langmuir : the ACS Journal of Surfaces and Colloids
|March 22, 2024
Summary
Polymer association in water is driven by entropy, not direct bonds. This entropy-driven mechanism, involving charge density, applies to both charged and non-ionic polymers, offering new insights into complex formation.
Area of Science:
- Polymer Science
- Physical Chemistry
- Biochemistry
Background:
- Interpolymer association in aqueous solutions is crucial for industry and biology.
- Current understanding lacks molecular details, necessitating deeper mechanistic insights.
Purpose of the Study:
- To investigate the molecular mechanisms driving polymer association in aqueous solutions.
- To propose a unifying mechanism applicable to both ionic and non-ionic polymers.
Main Methods:
- Consolidation of existing literature.
- Isothermal titration calorimetry (ITC) measurements.
- Molecular dynamics (MD) simulations.
Main Results:
- Intermolecular bonds (ionic, hydrogen) do not drive association; it is entropy-driven.
- Polymer association results from water and ion reorganization.
- Complementary charge densities are key for both polyions and polydipoles.
Conclusions:
- A unifying entropy-driven association mechanism is proposed for synthetic and biological polymers.
- Charge exchange and amphiphilic association are primary drivers.
- Amphiphilic assembly alone can initiate polymer association.
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