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Two different pathways for assembling bis-urea in benzene and toluene
Bruno Giordano Alvarenga1, Kalil Bernardino2, André Farias de Moura3
1Department of Physical Chemistry, Institute of Chemistry, State University of Campinas, CP 6154, Campinas, SP, CEP 13.083-970, Brazil.
Journal of Molecular Modeling
|June 9, 2018
Summary
The supramolecular polymer EHUT forms stable tubular assemblies in toluene and benzene. However, EHUT precipitates in benzene at lower temperatures due to weaker enthalpic stabilization compared to toluene.
Area of Science:
- Supramolecular Chemistry
- Materials Science
- Physical Chemistry
Background:
- Bis-urea based supramolecular polymers exhibit self-assembly properties.
- The thermodynamic stability of these polymers is influenced by solvent interactions.
- Understanding solvent effects is crucial for controlling self-assembled structures.
Purpose of the Study:
- To investigate the thermodynamic stability of 2,4-bis(2-ethylhexylureido)toluene (EHUT) supramolecular polymer assemblies.
- To compare the behavior of EHUT in benzene and toluene solvents upon cooling.
- To elucidate the molecular-level interactions governing differential solvent-induced precipitation.
Main Methods:
- Thermodynamic stability studies in solution using benzene and toluene.
- Observation of self-assembly into tubular structures upon cooling.
- Molecular dynamics simulations to analyze solvent-assembly interactions.
Main Results:
- EHUT forms stable tubular assemblies in both benzene and toluene across a wide temperature range.
- Below a critical temperature, EHUT precipitates in benzene but remains stable in toluene.
- Molecular dynamics simulations indicate stronger enthalpic stabilization of assemblies in toluene due to favorable toluene-EHUT interactions.
Conclusions:
- Solvent choice significantly impacts the long-term stability of EHUT supramolecular polymers.
- Favorable enthalpic interactions between toluene and EHUT contribute to enhanced assembly stability.
- Temperature-dependent solvent penetration affects the overall stability of the supramolecular structures.
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