Mechanical actuation by responsive polyelectrolyte brushes and triblock gels


Progress in the development of actuating molecular devices based on responsive polymers is reviewed. The synthesis and characterization of "grafted from brushes and triblock copolymers is reported. The responsive nature of polyelectrolyte brushes, grown by surface initiated atomic transfer radical polymerization (ATRP), has been characterized by scanning force microscopy, neutron reflectometry, and single molecule force measurements. The molecular response is measured directly for the brushes in terms of both the brush height and composition and the force generated by a single molecule. Triblock copolymers, based on hydrophobic end blocks and polyacid midblock, have been used to produce polymer gels where the deformation of the molecules can be followed directly by small angle Xray scattering (SAXS), and a correlation between molecular shape change and macroscopic deformation has been established. A Landolt pHoscillator, based on bromate/sulfite/ferrocyanide, with a room temperature period of 20 min and a range of 3.1 <pH <7.0, was used to drive periodic oscillations in volume in this pH responsive hydrogel. The triblock copolymers demonstrate that the individual response of the polyelectrolyte molecules scale affinely to produce the macroscopic response of the system in an oscillating chemical reaction.

Publication DOI:
Divisions: College of Engineering & Physical Sciences > School of Infrastructure and Sustainable Engineering > Chemical Engineering & Applied Chemistry
Additional Information: Copyright 2008 Elsevier B.V., All rights reserved.
Uncontrolled Keywords: actuating,triblock copolymers,molecular response
Publication ISSN: 1525-609X
Last Modified: 23 Oct 2019 14:08
Date Deposited: 16 Jul 2014 08:40
Full Text Link:
Related URLs: http://www.scop ... tnerID=8YFLogxK (Scopus URL)
Published Date: 2005-11
Authors: Ryan, A.J.
Crook, C.J.
Howse, J.R.
Topham, P. (ORCID Profile 0000-0003-4152-6976)
Geoghegan, M.
Martin, S.J.
Parnell, A.J.
Ruiz-Pérez, L.
Jones, R.A.L.


Item under embargo.

Export / Share Citation


Additional statistics for this record