Speaker
Marcelo Dias
(Aalto University and Nordita)
Description
Stimulus-induced shape change of soft materials opens the
door to a wide range of engineering applications from soft
robotics to artificial muscles. A particularly challenging
problem is concerned with manipulating the shape of these
materials so as to affect and control their response to
external stimuli. Heretofore, efforts in this direction have
been mainly devoted to obtaining three-dimensional
structures from the imposition of a two-dimensional pattern
on an isotropic material. Liquid-crystal elastomers (LCE)
are an even more promising class of soft materials for
actuation since they provide two forms of exploitable shape
transformation: prescriptions of the cross-link density to
control differential swelling, and an orientational order of
rod-like molecules that respond to internal and external
stimuli. In this talk I will present a phenomenological
model of strain-order coupling for shape formation in thin
elastic sheets of LCEs and show how the presence of the
nematic degree-of-freedom induces buckling instabilities in
these materials.
