The thinning of a cylinder of a polymer solution in a volatile solvent is argued to be controlled by solvent diffusion through a dense polymer layer at the cylinder surface. This naturally leads to the exponential time dependence of cylinder radius that is observed in experiments using a fast camera, such as capillary breakup extensional rheometry (CaBER). The relaxation time is controlled by the thickness of the dense (and often glassy) polymer layer and the diffusion coefficient of solvent through that layer. If correct, this means that while CaBER is very useful for understanding fiber spinning, the relaxation time does not yield a measure of the extensional viscosity of polymer solutions in volatile solvents.
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Spinning Molecules, Spinning Spins: Modulation of an Electron Spin Exchange Interaction in a Highly Anisotropic Hyperfine Field
- Award ID(s):
- 1900541
- PAR ID:
- 10359957
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- ACS Omega
- Volume:
- 6
- Issue:
- 42
- ISSN:
- 2470-1343
- Page Range / eLocation ID:
- p. 27865-27873
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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