DI-UMONS : Dépôt institutionnel de l’université de Mons

Recherche transversale
(titres de publication, de périodique et noms de colloque inclus)
2008-07-24 - Article/Dans un journal avec peer-review - Anglais - 7 page(s)

Shikata T., Nishida T., Isare B., Linares M., Lazzaroni Roberto , Bouteiller L., "Structure and Dynamics of a Bisurea-Based Supramolecular Polymer in n-Dodecane" in Journal of Physical Chemistry B, 112, 29, 8549-8465

  • Edition : American Chemical Society, Washington (DC)
  • Codes CREF : Chimie quantique (DI1321), Optique (DI1250)
  • Unités de recherche UMONS : Chimie des matériaux nouveaux (S817)
  • Instituts UMONS : Institut de Recherche en Science et Ingénierie des Matériaux (Matériaux)
Texte intégral :

Abstract(s) :

(Anglais) The structure and dynamics of a supramolecular polymer formed by a bisurea-type compound, 2,4-bis(2-ethylhexylureido)toluene (EHUT), in an apolar solvent, n-dodecane (C12), were examined in detail. The EHUT/C12 organo-gel system forms long, dynamic chain-like supramolecular polymers, which lead to an entangled network showing remarkable viscoelastic behavior with two major relaxation modes. A slow relaxation mode with an approximately constant relaxation time, tS, was observed in a flow region and the other, fast, relaxation mode with a time tF1 (<tS) was observed in a high-frequency range. Because no dielectric relaxation behavior was observed over a frequency region including the mechanical tS and tF1 relaxation modes, the formed supramolecular polymer does not possess any total dipole moment due to antiparallel intermolecular hydrogen bonding of the two ureido groups of each EHUT unit. A structural model for the supramolecular polymer formed in EHUT/C12 is proposed based on force-field simulations. This proposed model is consistent with all the experimental data concerning this system: flow birefringence measurements, dielectric spectroscopy, SANS, and FTIR.

Notes :
  • (Anglais) Publié en ligne le 26 juin 2008
Identifiants :
  • DOI : 10.1021/jp800495v