Congratulation to Tan Di for his article “R Switchable
Adhesion of Micropillar Adhesive on Rough Surfaces” has been published by Small.
Switchable structured adhesion on rough surfaces
is highly desired for a wide range of applications. Combing the advantages of
gecko seta and creeper root, a switchable fibrillar adhesive composed of polyurethane (PU)
as the backing layer and graphene/shape memory polymer (GSMP) as the pillar
array has been developed. The photothermal effect of graphene (under UV
irradiation) changes GSMP micropillars into viscoelastic state, allowing easy
and intimate contact on surfaces with a wide range of roughness. By controlling
the phase state of GSMP via UV irradiation during detachment, GSMP micropillar
array can be switched between robust-adhesion state (UV off) and low-adhesion
state (UV on). The state of GSMP micropillars determines the adhesion force
capacity and the stress distribution at the detaching interface, and therefore
the adhesion performance. The PU-GSMP adhesive achieves large adhesion strength
(278 kPa), high switching ratio (29), and fast switching (10 s) at the same
time. The results suggest a design principle for bioinspired structured
adhesives, especially for reversible adhesion on surfaces with a wide range of
roughnesses.
Highlighted by materialsviewschina: https://www.materialsviewschina.com/2019/11/41292/
Link: https://onlinelibrary.wiley.com/doi/10.1002/smll.201904248