Evidence of a Transition Layer between the Free Surface and the Bulk

Wojciech Ogieglo* (Corresponding Author), Kristianne Tempelman, Simone Napolitano, Nieck E. Benes

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

7 Citations (Scopus)
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Abstract

The free surface, a very thin layer at the interface between polymer and air, is considered the main source of the perturbations in the properties of ultrathin polymer films, i.e., nanoconfinement effects. The structural relaxation of such a layer is decoupled from the molecular dynamics of the bulk. The free surface is, in fact, able to stay liquid even below the temperature where the polymer resides in the glassy state. Importantly, this surface layer is expected to have a very sharp interface with the underlying bulk. Here, by analyzing the penetration of n-hexane into polystyrene films, we report on the existence of a transition region, not observed by previous investigations, extending for 12 nm below the free surface. The presence of such a layer permits reconciling the behavior of interfacial layers with current models and has profound implications on the performance of ultrathin membranes. We show that the expected increase in the flux of the permeating species is actually overruled by nanoconfinement.

Original languageEnglish
Pages (from-to)1195-1199
Number of pages5
JournalJournal of physical chemistry letters
Volume9
Issue number6
DOIs
Publication statusPublished - 21 Feb 2018

Fingerprint

transition layers
Polymers
polymers
permeating
Structural relaxation
Ultrathin films
Polystyrenes
guy wires
Hexane
Polymer films
Molecular dynamics
polystyrene
surface layers
penetration
Fluxes
molecular dynamics
membranes
Membranes
perturbation
air

Keywords

  • UT-Hybrid-D

Cite this

Ogieglo, Wojciech ; Tempelman, Kristianne ; Napolitano, Simone ; Benes, Nieck E. / Evidence of a Transition Layer between the Free Surface and the Bulk. In: Journal of physical chemistry letters. 2018 ; Vol. 9, No. 6. pp. 1195-1199.
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Evidence of a Transition Layer between the Free Surface and the Bulk. / Ogieglo, Wojciech (Corresponding Author); Tempelman, Kristianne; Napolitano, Simone; Benes, Nieck E.

In: Journal of physical chemistry letters, Vol. 9, No. 6, 21.02.2018, p. 1195-1199.

Research output: Contribution to journalArticleAcademicpeer-review

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