(504a) Programmable Deformation and Instability of Responsive Hydrogels | AIChE

(504a) Programmable Deformation and Instability of Responsive Hydrogels

Authors 

Kang, J. H. - Presenter, University of Massachusetts Amherst
Soft materials that respond to their surroundings are poised to become an indispensable
element of self-powered smart devices. To achieve proper functionality, these systems often
require precise chemical-mechanical coordination between various materials. In addition to
exploring new coupling mechanisms, thus, it is crucial to develop prototyping methodologies to
ease the integration of a variety of materials, especially those exhibiting emergent behavior
across different lengths and timescales.
In this talk, I will describe the rational strategies for shape-morphing soft materials based on
responsive hydrogels. First, I will discuss deformation-induced self-folding as a powerful
approach to creating complex 3D structures using planar patterning. However, due to the
bifurcated nature of the configuration space around the flat state, there is an inherent limitation
in terms of robustness. To address misfolding, the pre-biasing mechanism of microscale origami
is demonstrated by separating the actuation into two stages: vertex buckling and crease folding.
Second, I will discuss the dynamic movement and assembly of thermo-responsive hydrogel
nanocomposite films containing photochemically patterned plasmonic nanoparticles that
produce light-driven wrinkled structures at an air/water interface. Under patterned illumination,
distortion of the phase contact line causes capillary attraction and repulsion between multiple
disks, resulting in sustained motion under controlled instability. The design principles of
manipulating the specific desired properties of soft active matter using our advanced
manufacturing platform will open new avenues for the exploitation of such systems while
addressing the current challenges of biomimetic soft materials for biomedical, energy, and
environmental applications.