Fibers on the surface of thermo-responsive gels induce controllable formation of helical structure


We use computational modeling and analytical calculation to investigate the behavior of gel-fiber long thin films; we specifically show that the arrangement of fibers localization on the outer surface of the sample provides a powerful means of tailoring the overall shape of the sample, as to form helical structure with controlled chirality. We focus on thermo-responsive gels, which exhibit a lower critical solubility temperature (LCST) and thus shrink when heated above a certain temperature. The stiff fibers are attached to this gel and inhibit the nearby network from undergoing the heat-induced collapse. Away from the fibers, however, the network can readily shrink in response to the increased temperature. This competition between the constrained regions and the unconstrained regions of the heated gel regulates the structural evolution and final geometry of the sample. Our simulations use the gel lattice spring model (gLSM) to determine how the temperature, arrangement and number of the fibers control the bending and twisting of thin ribbons. Our comprehensive 3D analytical calculation incorporates elasticity, differential geometry, and variational principles.

Mar 4, 2020 11:15 AM
Denver, Colorado, USA
Tao Zhang
Tao Zhang
Special Research Fellow