Abstract
The kinetics of heat-induced gelation and the microscopic dynamics of a hen egg white gel are probed using x-ray photon correlation spectroscopy along with ultrasmall-angle x-ray scattering. The kinetics of structural growth reveals a reaction-limited aggregation process with a gel fractal dimension of and an average network mesh size of ca. 400 nm. The dynamics probed at these length scales reveals an exponential growth of the characteristic relaxation times followed by an intriguing steady state in combination with a compressed exponential correlation function and a temporal heterogeneity. The degree of heterogeneity increases with decreasing length scale. We discuss our results in the broader context of experiments and models describing attractive colloidal gels.
- Received 23 July 2020
- Revised 12 November 2020
- Accepted 11 January 2021
DOI:https://doi.org/10.1103/PhysRevLett.126.098001
© 2021 American Physical Society
Physics Subject Headings (PhySH)
synopsis
Watching an Egg Cook with X Rays
Published 2 March 2021
An x-ray scattering technique reveals how egg whites gel on a range of length and timescales.
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