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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Two different pathways for assembling bis-urea in benzene and toluene

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Alvarenga, Bruno Giordano [1] ; Bernardino, Kalil [2] ; de Moura, Andre Farias [2] ; Sabadini, Edvaldo [1]
Total Authors: 4
[1] Univ Estadual Campinas, Inst Chem, Dept Phys Chem, CP 6154, BR-13083970 Campinas, SP - Brazil
[2] Univ Fed Sao Carlos, Dept Chem, Rodovia Washington Luis Km 235, CP 676, BR-13565905 Sao Carlos, SP - Brazil
Total Affiliations: 2
Document type: Journal article
Source: Journal of Molecular Modeling; v. 24, n. 7 JUL 2018.
Web of Science Citations: 0

The thermodynamic stability of assemblies formed by a bis-urea-based supramolecular polymer, 2,4-bis(2-ethylhexylureido)toluene (EHUT), was investigated in solutions using either benzene or toluene as the solvent. Starting from a higher temperature in which EHUT was soluble in both solvents, molecules spontaneously self-organized into tubular assemblies upon cooling and these assemblies were stable in a wide range of temperatures. However, the systems followed different paths below a specific temperature: while the supramolecular polymer remained stable in toluene, EHUT molecules underwent precipitation in benzene. The causes for these different behaviors were explored by molecular dynamics simulations, which provided support for stronger enthalpic stabilization of the tubular assemblies in toluene as compared to benzene. This stabilization was due mainly to the better interaction energy of trapped toluene molecules instead of benzene ones. For both cases, lowering the temperature makes the solvent penetration inside the tubes less favorable, which reduces the stability of supramolecular structures upon cooling. (AU)

FAPESP's process: 14/04515-8 - Supramolecular polymers of bis-ureia in solution: balance of solute-solvent interaction
Grantee:Bruno Giordano Alvarenga
Support type: Scholarships in Brazil - Doctorate
FAPESP's process: 13/07296-2 - CDMF - Center for the Development of Functional Materials
Grantee:Elson Longo da Silva
Support type: Research Grants - Research, Innovation and Dissemination Centers - RIDC
FAPESP's process: 12/15147-4 - Computational study of the association thermodynamics of self­Assembled systems
Grantee:André Farias de Moura
Support type: Regular Research Grants