Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Science 29 August 1997:
Vol. 277. no. 5330, pp. 1248 - 1253
DOI: 10.1126/science.277.5330.1248
Prev | Table of Contents | Next

Articles

Pathways to Macroscale Order in Nanostructured Block Copolymers

Zhong-Ren Chen, Julia A. Kornfield, * Steven D. Smith, Jeffrey T. Grothaus, Michael M. Satkowski

Polymeric materials undergo dramatic changes in orientational order in response to dynamic processes, such as flow. Their rich cascade of dynamics presents opportunities to create and combine distinct alignments of polymeric nanostructures through processing. In situ rheo-optical measurements complemented by ex situ x-ray scattering reveal the physics of three different trajectories to macroscopic alignment of lamellar diblock copolymers during oscillatory shearing. At the highest frequencies, symmetry arguments explain the transient development of a bimodal texture en route to the alignment of layers parallel to the planes of shear. At lower frequencies, larger-scale relaxations introduce rearrangements out of the deformation plane that permit the formation of lamellae perpendicular to the shear plane. These explain the change in the character of the pathway to parallel alignment and the emergence of perpendicular alignment as the frequency decreases.

Z.-R. Chen and J. A. Kornfield, California Institute of Technology, Chemical Engineering 210-41, Pasadena, CA 91125, USA.
S. D. Smith, J. T. Grothaus, M. M. Satkowski, Procter and Gamble, Miami Valley Laboratories, Cincinnati, OH 45239, USA.
*   To whom correspondence should be addressed.

Volume 277, Number 5330, Issue of 29 August 1997, pp. 1248-1253
©1997 by The American Association for the Advancement of Science.

Read the Full Text


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Real science at the petascale.
R. S. Saksena, B. Boghosian, L. Fazendeiro, O. A. Kenway, S. Manos, M. D. Mazzeo, S. K. Sadiq, J. L. Suter, D. Wright, and P. V. Coveney (2009)
Phil Trans R Soc A 367, 2557-2571
   Abstract »    Full Text »    PDF »
Rheological response and dynamics of the amphiphilic diamond phase from kinetic lattice-Boltzmann simulations.
R.S. Saksena and P.V. Coveney (2009)
Proc R Soc A 465, 1977-2002
   Abstract »    Full Text »    PDF »
Confined Crystallization of Polyethylene Oxide in Nanolayer Assemblies.
H. Wang, J. K. Keum, A. Hiltner, E. Baer, B. Freeman, A. Rozanski, and A. Galeski (2009)
Science 323, 757-760
   Abstract »    Full Text »    PDF »


To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)