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Title: Extracting the surface tension of soft gels from elastocapillary wave behavior
Mechanically-excited waves appear as surface patterns on soft agarose gels. We experimentally quantify the dispersion relationship for these waves over a range of shear modulus in the transition zone where the surface energy (capillarity) is comparable to the elastic energy of the solid. Rayleigh waves and capillary-gravity waves are recovered as limiting cases. Gravitational forces appear as a pre-stress through the self-weight of the gel and are important. We show the experimental data fits well to a proposed dispersion relationship which differs from that typically used in studies of capillary to elastic wave crossover. We use this combined theoretical and experimental analysis to develop a new technique for measuring the surface tension of soft materials, which has been historically difficult to measure directly.  more » « less
Award ID(s):
1750208
PAR ID:
10085588
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Soft Matter
Volume:
14
Issue:
36
ISSN:
1744-683X
Page Range / eLocation ID:
7347 to 7353
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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