TY - JOUR
T1 - Covalent-supramolecular hybrid polymers as muscle-inspired anisotropic actuators
AU - Chin, Stacey M.
AU - Synatschke, Christopher V.
AU - Liu, Shuangping
AU - Nap, Rikkert J.
AU - Sather, Nicholas A.
AU - Wang, Qifeng
AU - Álvarez, Zaida
AU - Edelbrock, Alexandra N.
AU - Fyrner, Timmy
AU - Palmer, Liam C.
AU - Szleifer, Igal
AU - Olvera De La Cruz, Monica
AU - Stupp, Samuel I.
N1 - Funding Information:
This work was primarily supported by the Center for Bio-Inspired Energy Science, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences under Award # DE-SC0000989. The 3D printing experiments were supported by the Air Force Research Laboratory under agreement number FA8650-15-2-5518. The U.S. Government is authorized to reproduce and distribute reprints for Governmental purposes notwithstanding any copyright notation thereon. The views and conclusions contained herein are those of the authors and should not be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of Air Force Research Laboratory or the U.S. Government. S.M.C.
Funding Information:
and A.N.E. acknowledge graduate research fellowships through the National Science Foundation. C.V.S. acknowledges a Feodor Lynen-postdoctoral fellowship through the Humboldt Foundation. Z.A. has received postdoctoral support from the Beatriu de Pinós Fellowship 2014 BP-A 00007 (Agència de Gestió d’Ajust Universitaris i de Recerca, AGAUR), and by Grant #PVA17_RF_0008 from the PVA Research Foundation. N.A.S. was supported by the Department of Defense (DoD), Air Force Office of Scientific Research, through the National Defense Science and Engineering Graduate (NDSEG) Fellowship, 32 CFR 168a and also acknowledges support from Northwestern University International Institute for Nanotechnology through a Ryan Fellowship. X-ray diffraction was performed at the DuPont-Northwestern-Dow Collaborative Access Team (DND-CAT) located at Sector 5 of the Advanced Photon Source (APS). DND-CAT is supported by Northwestern University, E.I. DuPont de Nemours & Co., and The Dow Chemical Company. This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. This work used the following core facilities at Northwestern University: the Peptide Synthesis Core Facility and the Analytical BioNanoTechnology Equipment Core facility (ANTEC) of the Simpson Querrey Institute for peptide synthesis and purification, the Integrated Molecular Structure Education and Research Center (IMSERC) for NMR spectroscopy and GPC, the EPIC facility of Northwestern’s NUANCE Center for SEM and DLS, the Biological Imaging Facility (BIF) for TEM, the Central Laboratory for Materials Mechanical Properties (CLaMMP) for tensile testing, and the Center for Advanced Microscopy (CAM) for fluorescence microscopy. The authors thank M. Seniw and B. Jones for the preparation of illustrations, and H. Sai for scientific discussion of SAXS data.
Publisher Copyright:
© 2018 The Author(s).
PY - 2018/12/1
Y1 - 2018/12/1
N2 - Skeletal muscle provides inspiration on how to achieve reversible, macroscopic, anisotropic motion in soft materials. Here we report on the bottom-up design of macroscopic tubes that exhibit anisotropic actuation driven by a thermal stimulus. The tube is built from a hydrogel in which extremely long supramolecular nanofibers are aligned using weak shear forces, followed by radial growth of thermoresponsive polymers from their surfaces. The hierarchically ordered tube exhibits reversible anisotropic actuation with changes in temperature, with much greater contraction perpendicular to the direction of nanofiber alignment. We identify two critical factors for the anisotropic actuation, macroscopic alignment of the supramolecular scaffold and its covalent bonding to polymer chains. Using finite element analysis and molecular calculations, we conclude polymer chain confinement and mechanical reinforcement by rigid supramolecular nanofibers are responsible for the anisotropic actuation. The work reported suggests strategies to create soft active matter with molecularly encoded capacity to perform complex tasks.
AB - Skeletal muscle provides inspiration on how to achieve reversible, macroscopic, anisotropic motion in soft materials. Here we report on the bottom-up design of macroscopic tubes that exhibit anisotropic actuation driven by a thermal stimulus. The tube is built from a hydrogel in which extremely long supramolecular nanofibers are aligned using weak shear forces, followed by radial growth of thermoresponsive polymers from their surfaces. The hierarchically ordered tube exhibits reversible anisotropic actuation with changes in temperature, with much greater contraction perpendicular to the direction of nanofiber alignment. We identify two critical factors for the anisotropic actuation, macroscopic alignment of the supramolecular scaffold and its covalent bonding to polymer chains. Using finite element analysis and molecular calculations, we conclude polymer chain confinement and mechanical reinforcement by rigid supramolecular nanofibers are responsible for the anisotropic actuation. The work reported suggests strategies to create soft active matter with molecularly encoded capacity to perform complex tasks.
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U2 - 10.1038/s41467-018-04800-w
DO - 10.1038/s41467-018-04800-w
M3 - Article
C2 - 29921928
AN - SCOPUS:85048783074
VL - 9
JO - Nature Communications
JF - Nature Communications
SN - 2041-1723
IS - 1
M1 - 2395
ER -