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Title: Roughness tolerant pressure sensitive adhesives made of sticky crumpled sheets
If an adhesive is meant to be temporary, roughness often poses a challenge for design. An adhesive could be made soft so that it can deform and increase surface contact but a softer material will in general hold a smaller load. Bioinspired adhesives, made with numerous microscale posts, show promise as roughness tolerant adhesives but are complicated to fabricate. In this work, we show how thin polymer sheets, when crumpled into a roughly spherical shape, form a very simple and roughness tolerant adhesive system. We use micro and macro-scale experiments to measure adhesion forces between various substrates and crumpled polydimethylsiloxane sheets. We find the force-displacement curves resemble probe-tack experiments of traditional pressure sensitive adhesives and that moderate tensile forces are required to initiate interfacial failure. Notably, we see that sticky crumples often perform better on long wavelength roughness than they do on smooth substrates. In order to improve the peak pull-off forces, we create a sticky crumple from a thin sheet of a glassy polymer, polycarbonate, coated with an adhesive layer. This elasto-plastic sticky crumple achieves high pull-off forces even on the rough surface of a landscaping brick.  more » « less
Award ID(s):
2011681
PAR ID:
10464144
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Soft Matter
Volume:
18
Issue:
40
ISSN:
1744-683X
Page Range / eLocation ID:
7866 to 7876
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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