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Title: Evolution of critical buckling conditions in imperfect bilayer shells through residual swelling
We propose and investigate a minimal mechanism that makes use of differential swelling to modify the critical buckling conditions of elastic bilayer shells, as measured by the knockdown factor. Our shells contain an engineered defect at the north pole and are made of two layers of different crosslinked polymers that exchange free molecular chains. Depending on the size of the defect and the extent of swelling, we can observe either a decreasing or increasing knockdown factor. FEM simulations are performed using a reduced model for the swelling process to aid us in rationalizing the underlying mechanism, providing a qualitative agreement with experiments. We believe that the working principle of our mechanism can be extended to bimetallic shells undergoing variations in temperature and to shells made of pH-responsive gels, where the change in knockdown factor could be changed dynamically.  more » « less
Award ID(s):
1824882
NSF-PAR ID:
10122586
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Soft Matter
Volume:
15
Issue:
30
ISSN:
1744-683X
Page Range / eLocation ID:
6134 to 6144
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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