Polymer confinement at nanometer length scales can lead to significant changes in physicochemical properties including chain conformation and macromolecular relaxation. In this work, two-dimensional confinement of the ubiquitous polymer poly(ethylene oxide) was achieved via its intercalation into graphite oxide, leading to well defined (subnanometer) polymer layers of thickness ~3.4 Å.
The extreme spatial confinement of the polymer phase is responsible for the suppression of crystallization and cooperative relaxation processes. For the first time, high-resolution inelastic neutron scattering experiments on Tosca show that poly(ethylene oxide) under these extreme confinement conditions adopts a planar zig-zag conformation which in no way resembles the characteristic helical structure of the bulk crystal. Moreover, the neutron data also account for a drastic reduction in long-range order and chain mobility.
F Barroso-Bujans, S Cerveny, A Alegría, J Colmenero (CSIC/UPV-EHU, Spain), F Fernandez-Alonso, SF Parker (ISIS)
Research date: August 2011
Contact: Dr F Barroso-Bujans, firstname.lastname@example.org
Further reading: F Barroso-Bujans et al.,
Soft Matter 7 (2011) 7173