Publications
Liu, Jiayu; Erol, Ozan; Pantula, Aishwarya; Liu, Wangqu; Jiang, Zhuoran; Kobayashi, Kunihiko; Chatterjee, Devina; Hibino, Narutoshi; Romer, Lewis H.; Kang, Sung Hoon; Nguyen, Thao D.; Gracias, David H.
Dual-Gel 4D Printing of Bioinspired Tubes Journal Article
In: ACS Applied Materials & Interfaces, 2019.
@article{doi:10.1021/acsami.8b17218,
title = {Dual-Gel 4D Printing of Bioinspired Tubes},
author = {Jiayu Liu and Ozan Erol and Aishwarya Pantula and Wangqu Liu and Zhuoran Jiang and Kunihiko Kobayashi and Devina Chatterjee and Narutoshi Hibino and Lewis H. Romer and Sung Hoon Kang and Thao D. Nguyen and David H. Gracias},
url = {https://doi.org/10.1021/acsami.8b17218},
doi = {10.1021/acsami.8b17218},
year = {2019},
date = {2019-01-29},
journal = {ACS Applied Materials & Interfaces},
abstract = {The distribution of periodic patterns of materials with radial or bilateral symmetry is a universal natural design principle. Among the many biological forms, tubular shapes are a common motif in many organisms, and they are also important for bioimplants and soft robots. However, the simple design principle of strategic placement of 3D printed segments of swelling and nonswelling materials to achieve widely different functionalities is yet to be demonstrated. Here, we report the design, fabrication, and characterization of segmented 3D printed gel tubes composed of an active thermally responsive swelling gel (poly N-isopropylacrylamide) and a passive thermally nonresponsive gel (polyacrylamide). Using finite element simulations and experiments, we report a variety of shape changes including uniaxial elongation, radial expansion, bending, and gripping based on two gels. Actualization and characterization of thermally induced shape changes are of key importance to robotics and biomedical engineering. Our studies present rational approaches to engineer complex parameters with a high level of customization and tunability for additive manufacturing of dynamic gel structures.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Shim, Jongmin; Shan, Sicong; Kosmrlj, Andrej; Kang, Sung Hoon; Chen, Elizabeth R.; Weaver, James C.; Bertoldi, Katia
Harnessing Instabilities for Design of Soft Reconfigurable Auxetic/Chiral Materials Journal Article
In: Soft Matter, vol. 9, pp. 8198-8202, 2013, (Highlighted on the Soft Matter blog.).
@article{Shim2013,
title = {Harnessing Instabilities for Design of Soft Reconfigurable Auxetic/Chiral Materials},
author = {Jongmin Shim and Sicong Shan and Andrej Kosmrlj and Sung Hoon Kang and Elizabeth R. Chen and James C. Weaver and Katia Bertoldi},
url = {http://pubs.rsc.org/en/content/articlelanding/2013/sm/c3sm51148k#!divAbstract},
year = {2013},
date = {2013-05-31},
journal = {Soft Matter},
volume = {9},
pages = {8198-8202},
abstract = {Most materials have a unique form optimized for a specific property and function. However, the ability to reconfigure material structures depending on stimuli opens exciting opportunities. Although mechanical instabilities have been traditionally viewed as a failure mode, here we exploit them to design a class of 2D soft materials whose architecture can be dramatically changed in response to an external stimulus. By considering geometric constraints on the tessellations of the 2D Euclidean plane, we have identified four possible periodic distributions of uniform circular holes where mechanical instability can be exploited to reversibly switch between expanded (i.e. with circular holes) and compact (i.e. with elongated, almost closed elliptical holes) periodic configurations. Interestingly, in all these structures buckling is found to induce large negative values of incremental Poisson's ratio and in two of them also the formation of chiral patterns. Using a combination of finite element simulations and experiments at the centimeter scale we demonstrate a proof-of-concept of the proposed materials. Since the proposed mechanism for reconfigurable materials is induced by elastic instability, it is reversible, repeatable and scale-independent.},
note = {Highlighted on the Soft Matter blog.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Kang, Sung Hoon; Shan, Sicong; Noorduin, Wim L.; Khan, Mughees; Aizenberg, Joanna; Bertoldi, Katia
Buckling-Induced Reversible Symmetry Breaking and Chiral Amplification Using Supported Cellular Structures Journal Article
In: Advanced Materials, vol. 25, pp. 3380-3385, 2013, (SHK, SS, and WLN contributed equally. Highlighted in the June 2013 issue of Nature Physics).
@article{Kang2013,
title = {Buckling-Induced Reversible Symmetry Breaking and Chiral Amplification Using Supported Cellular Structures},
author = {Sung Hoon Kang and Sicong Shan and Wim L. Noorduin and Mughees Khan and Joanna Aizenberg and Katia Bertoldi},
url = {http://onlinelibrary.wiley.com/doi/10.1002/adma.201300617/abstract},
year = {2013},
date = {2013-05-02},
journal = {Advanced Materials},
volume = {25},
pages = {3380-3385},
abstract = {Buckling-induced reversible symmetry breaking and amplification of chirality using macro- and microscale supported cellular structures is described. Guided by extensive theoretical analysis, cellular structures are rationally designed, in which buckling induces a reversible switching between achiral and chiral configurations. Additionally, it is demonstrated that the proposed mechanism can be generalized over a wide range of length scales, geometries, materials, and stimuli. },
note = {SHK, SS, and WLN contributed equally.
Highlighted in the June 2013 issue of Nature Physics},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Note: Send e-mail to Prof. Kang at [email protected] if you need a pdf file of the papers below.
2019

Liu, Jiayu; Erol, Ozan; Pantula, Aishwarya; Liu, Wangqu; Jiang, Zhuoran; Kobayashi, Kunihiko; Chatterjee, Devina; Hibino, Narutoshi; Romer, Lewis H.; Kang, Sung Hoon; Nguyen, Thao D.; Gracias, David H.
Dual-Gel 4D Printing of Bioinspired Tubes Journal Article
In: ACS Applied Materials & Interfaces, 2019.
Abstract | Links | BibTeX | Tags: 3D printing; architected materials; multilateral; mechanics of soft materials and structures; stimuli-responsive; implants; 4D printing; biomedical engineering, bio-inspired science and engineering, Symmetry Breaking
@article{doi:10.1021/acsami.8b17218,
title = {Dual-Gel 4D Printing of Bioinspired Tubes},
author = {Jiayu Liu and Ozan Erol and Aishwarya Pantula and Wangqu Liu and Zhuoran Jiang and Kunihiko Kobayashi and Devina Chatterjee and Narutoshi Hibino and Lewis H. Romer and Sung Hoon Kang and Thao D. Nguyen and David H. Gracias},
url = {https://doi.org/10.1021/acsami.8b17218},
doi = {10.1021/acsami.8b17218},
year = {2019},
date = {2019-01-29},
journal = {ACS Applied Materials & Interfaces},
abstract = {The distribution of periodic patterns of materials with radial or bilateral symmetry is a universal natural design principle. Among the many biological forms, tubular shapes are a common motif in many organisms, and they are also important for bioimplants and soft robots. However, the simple design principle of strategic placement of 3D printed segments of swelling and nonswelling materials to achieve widely different functionalities is yet to be demonstrated. Here, we report the design, fabrication, and characterization of segmented 3D printed gel tubes composed of an active thermally responsive swelling gel (poly N-isopropylacrylamide) and a passive thermally nonresponsive gel (polyacrylamide). Using finite element simulations and experiments, we report a variety of shape changes including uniaxial elongation, radial expansion, bending, and gripping based on two gels. Actualization and characterization of thermally induced shape changes are of key importance to robotics and biomedical engineering. Our studies present rational approaches to engineer complex parameters with a high level of customization and tunability for additive manufacturing of dynamic gel structures.},
keywords = {3D printing; architected materials; multilateral; mechanics of soft materials and structures; stimuli-responsive; implants; 4D printing; biomedical engineering, bio-inspired science and engineering, Symmetry Breaking},
pubstate = {published},
tppubtype = {article}
}
2013

Shim, Jongmin; Shan, Sicong; Kosmrlj, Andrej; Kang, Sung Hoon; Chen, Elizabeth R.; Weaver, James C.; Bertoldi, Katia
Harnessing Instabilities for Design of Soft Reconfigurable Auxetic/Chiral Materials Journal Article
In: Soft Matter, vol. 9, pp. 8198-8202, 2013, (Highlighted on the Soft Matter blog.).
Abstract | Links | BibTeX | Tags: 3D printing, architected materials, Auxetic, Chiral, Mechanical Instability, mechanics of soft materials and structures, Metamaterial, Soft Periodic Porous Structures, Symmetry Breaking
@article{Shim2013,
title = {Harnessing Instabilities for Design of Soft Reconfigurable Auxetic/Chiral Materials},
author = {Jongmin Shim and Sicong Shan and Andrej Kosmrlj and Sung Hoon Kang and Elizabeth R. Chen and James C. Weaver and Katia Bertoldi},
url = {http://pubs.rsc.org/en/content/articlelanding/2013/sm/c3sm51148k#!divAbstract},
year = {2013},
date = {2013-05-31},
journal = {Soft Matter},
volume = {9},
pages = {8198-8202},
abstract = {Most materials have a unique form optimized for a specific property and function. However, the ability to reconfigure material structures depending on stimuli opens exciting opportunities. Although mechanical instabilities have been traditionally viewed as a failure mode, here we exploit them to design a class of 2D soft materials whose architecture can be dramatically changed in response to an external stimulus. By considering geometric constraints on the tessellations of the 2D Euclidean plane, we have identified four possible periodic distributions of uniform circular holes where mechanical instability can be exploited to reversibly switch between expanded (i.e. with circular holes) and compact (i.e. with elongated, almost closed elliptical holes) periodic configurations. Interestingly, in all these structures buckling is found to induce large negative values of incremental Poisson's ratio and in two of them also the formation of chiral patterns. Using a combination of finite element simulations and experiments at the centimeter scale we demonstrate a proof-of-concept of the proposed materials. Since the proposed mechanism for reconfigurable materials is induced by elastic instability, it is reversible, repeatable and scale-independent.},
note = {Highlighted on the Soft Matter blog.},
keywords = {3D printing, architected materials, Auxetic, Chiral, Mechanical Instability, mechanics of soft materials and structures, Metamaterial, Soft Periodic Porous Structures, Symmetry Breaking},
pubstate = {published},
tppubtype = {article}
}

Kang, Sung Hoon; Shan, Sicong; Noorduin, Wim L.; Khan, Mughees; Aizenberg, Joanna; Bertoldi, Katia
Buckling-Induced Reversible Symmetry Breaking and Chiral Amplification Using Supported Cellular Structures Journal Article
In: Advanced Materials, vol. 25, pp. 3380-3385, 2013, (SHK, SS, and WLN contributed equally. Highlighted in the June 2013 issue of Nature Physics).
Abstract | Links | BibTeX | Tags: 3D printing, Amplification, Cellular Structures, Mechanical Instability, mechanics of soft materials and structures, Reversible, Symmetry Breaking
@article{Kang2013,
title = {Buckling-Induced Reversible Symmetry Breaking and Chiral Amplification Using Supported Cellular Structures},
author = {Sung Hoon Kang and Sicong Shan and Wim L. Noorduin and Mughees Khan and Joanna Aizenberg and Katia Bertoldi},
url = {http://onlinelibrary.wiley.com/doi/10.1002/adma.201300617/abstract},
year = {2013},
date = {2013-05-02},
journal = {Advanced Materials},
volume = {25},
pages = {3380-3385},
abstract = {Buckling-induced reversible symmetry breaking and amplification of chirality using macro- and microscale supported cellular structures is described. Guided by extensive theoretical analysis, cellular structures are rationally designed, in which buckling induces a reversible switching between achiral and chiral configurations. Additionally, it is demonstrated that the proposed mechanism can be generalized over a wide range of length scales, geometries, materials, and stimuli. },
note = {SHK, SS, and WLN contributed equally.
Highlighted in the June 2013 issue of Nature Physics},
keywords = {3D printing, Amplification, Cellular Structures, Mechanical Instability, mechanics of soft materials and structures, Reversible, Symmetry Breaking},
pubstate = {published},
tppubtype = {article}
}