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Title: Reversible Tuning of a Block Copolymer Nanostructure via Electric Fields

Abstract

Block copolymers consisting of incompatible components self-assemble into microphase-separated domains yielding highly regular structures with characteristic length scales of the order of several tens of nanometres. Therefore, in the past decades, block copolymers have gained considerable potential for nanotechnological applications, such as in nanostructured networks and membranes, nanoparticle templates and high-density data storage media. However, the characteristic size of the resulting structures is usually determined by molecular parameters of the constituent polymer molecules and cannot easily be adjusted on demand. Here, we show that electric d.c. fields can be used to tune the characteristic spacing of a block-copolymer nanostructure with high accuracy by as much as 6% in a fully reversible way on a timescale in the range of several milliseconds. We discuss the influence of various physical parameters on the tuning process and study the time response of the nanostructure to the applied field. A tentative explanation of the observed effect is given on the basis of anisotropic polarizabilities and permanent dipole moments of the monomeric constituents. This electric-field-induced effect further enhances the high technological potential of block-copolymer-based soft-lithography applications.

Authors:
 [1];  [2];  [1];  [2];  [3];  [4];  [2];  [1]
  1. Universitat Bayreuth
  2. University of Bayreuth
  3. European Synchrotron Radiation Facility (ESRF)
  4. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Laboratory Directed Research and Development (LDRD) Program
OSTI Identifier:
931045
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Nature Materials; Journal Volume: 7; Journal Issue: 2
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; COPOLYMERS; ELECTRIC FIELDS; NANOSTRUCTURES; TUNING

Citation Formats

Schmidt, K., Schoberth, Heiko, Ruppel, Markus A., Zettl, H, Weiss, Thomas, Urban, Volker S, Krausch, G, and Boker, A. Reversible Tuning of a Block Copolymer Nanostructure via Electric Fields. United States: N. p., 2007. Web.
Schmidt, K., Schoberth, Heiko, Ruppel, Markus A., Zettl, H, Weiss, Thomas, Urban, Volker S, Krausch, G, & Boker, A. Reversible Tuning of a Block Copolymer Nanostructure via Electric Fields. United States.
Schmidt, K., Schoberth, Heiko, Ruppel, Markus A., Zettl, H, Weiss, Thomas, Urban, Volker S, Krausch, G, and Boker, A. Mon . "Reversible Tuning of a Block Copolymer Nanostructure via Electric Fields". United States. doi:.
@article{osti_931045,
title = {Reversible Tuning of a Block Copolymer Nanostructure via Electric Fields},
author = {Schmidt, K. and Schoberth, Heiko and Ruppel, Markus A. and Zettl, H and Weiss, Thomas and Urban, Volker S and Krausch, G and Boker, A.},
abstractNote = {Block copolymers consisting of incompatible components self-assemble into microphase-separated domains yielding highly regular structures with characteristic length scales of the order of several tens of nanometres. Therefore, in the past decades, block copolymers have gained considerable potential for nanotechnological applications, such as in nanostructured networks and membranes, nanoparticle templates and high-density data storage media. However, the characteristic size of the resulting structures is usually determined by molecular parameters of the constituent polymer molecules and cannot easily be adjusted on demand. Here, we show that electric d.c. fields can be used to tune the characteristic spacing of a block-copolymer nanostructure with high accuracy by as much as 6% in a fully reversible way on a timescale in the range of several milliseconds. We discuss the influence of various physical parameters on the tuning process and study the time response of the nanostructure to the applied field. A tentative explanation of the observed effect is given on the basis of anisotropic polarizabilities and permanent dipole moments of the monomeric constituents. This electric-field-induced effect further enhances the high technological potential of block-copolymer-based soft-lithography applications.},
doi = {},
journal = {Nature Materials},
number = 2,
volume = 7,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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