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Flow-induced gelation of living (micellar) polymersThe effect of shear velocity gradients on the size (L) of rodlike micelles in dilute and semidilute solution is considered. A kinetic equation is introduced for the time-dependent concentration of aggregates of length L, consisting of 'bimolecular' combination processes L + L-prime yield (L + L-prime) and unimolecular fragmentations L yield L + (L - L-prime). The former are described by a generalization (from spheres to rods) of the Smoluchowski mechanism for shear-induced coalesence of emulsions, and the latter by incorporating the tension-deformation effects due to flow. Steady-state solutions to the kinetic equation are obtained, with the corresponding mean micellar size evaluated as a function of the Peclet number P (i.e., the dimensionless ratio of the flow rate and the rotational diffusion coefficient). For sufficiently dilute solutions, only a weak dependence of the micellar size on P is found. In the semidilute regime, however, an apparent divergence in the micellar size at P of about 1 suggests a flow-induced first-order gelation phenomenon.
Document ID
19920056318
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Bruinsma, Robijn
(NASA Headquarters Washington, DC United States)
Gelbart, William M.
(California, University Los Angeles, United States)
Ben-Shaul, Avinoam
(Jerusalem, Hebrew University Israel)
Date Acquired
August 15, 2013
Publication Date
May 15, 1992
Publication Information
Publication: Journal of Chemical Physics
Volume: 96
Issue: 10 M
ISSN: 0021-9606
Subject Category
Nonmetallic Materials
Accession Number
92A38942
Funding Number(s)
CONTRACT_GRANT: NSF PHY-82-17853
CONTRACT_GRANT: NSF CHE-88-16059
Distribution Limits
Public
Copyright
Other

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