Publications
1.
Orrego, Santiago; Chen, Zhezhi; Krekora, Urszula; Hou, Decheng; Jeon, Seung‐Yeol; Pittman, Matthew; Montoya, Carolina; Chen, Yun; Kang, Sung Hoon
Bioinspired Materials with Self‐Adaptable Mechanical Properties Journal Article
In: Advanced Materials, 2020.
@article{Orrego2020,
title = {Bioinspired Materials with Self‐Adaptable Mechanical Properties},
author = {Santiago Orrego and Zhezhi Chen and Urszula Krekora and Decheng Hou and Seung‐Yeol Jeon and Matthew Pittman and Carolina Montoya and Yun Chen and Sung Hoon Kang},
url = {https://onlinelibrary.wiley.com/doi/full/10.1002/adma.201906970},
doi = {https://doi.org/10.1002/adma.201906970},
year = {2020},
date = {2020-04-17},
journal = {Advanced Materials},
abstract = {Natural structural materials, such as bone, can autonomously modulate their mechanical properties in response to external loading to prevent failure. These material systems smartly control the addition/removal of material in locations of high/low mechanical stress by utilizing local resources guided by biological signals. On the contrary, synthetic structural materials have unchanging mechanical properties limiting their mechanical performance and service life. Inspired by the mineralization process of bone, a material system that adapts its mechanical properties in response to external mechanical loading is reported. It is found that charges from piezoelectric scaffolds can induce mineralization from surrounding media. It is shown that the material system can adapt to external mechanical loading by inducing mineral deposition in proportion to the magnitude of the stress and the resulting piezoelectric charges. Moreover, the mineralization mechanism allows a simple one‐step route for fabricating functionally graded materials by controlling the stress distribution along the scaffold. The findings can pave the way for a new class of self‐regenerating materials that reinforce regions of high stress or induce deposition of minerals on the damaged areas from the increase in mechanical stress to prevent/mitigate failure. It is envisioned that the findings can contribute to addressing the current challenges of synthetic materials for load‐bearing applications from self‐adaptive capabilities.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Natural structural materials, such as bone, can autonomously modulate their mechanical properties in response to external loading to prevent failure. These material systems smartly control the addition/removal of material in locations of high/low mechanical stress by utilizing local resources guided by biological signals. On the contrary, synthetic structural materials have unchanging mechanical properties limiting their mechanical performance and service life. Inspired by the mineralization process of bone, a material system that adapts its mechanical properties in response to external mechanical loading is reported. It is found that charges from piezoelectric scaffolds can induce mineralization from surrounding media. It is shown that the material system can adapt to external mechanical loading by inducing mineral deposition in proportion to the magnitude of the stress and the resulting piezoelectric charges. Moreover, the mineralization mechanism allows a simple one‐step route for fabricating functionally graded materials by controlling the stress distribution along the scaffold. The findings can pave the way for a new class of self‐regenerating materials that reinforce regions of high stress or induce deposition of minerals on the damaged areas from the increase in mechanical stress to prevent/mitigate failure. It is envisioned that the findings can contribute to addressing the current challenges of synthetic materials for load‐bearing applications from self‐adaptive capabilities.
2.
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}
}
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.
3.
Aizenberg, Joanna; He, Ximin; Kang, Sung Hoon; Wong, Tak-Sing
Anti-counterfeiting methods Technical Report
2013, (U.S. Patent No. 9,937,743 B2).
@techreport{Aizenberg2012,
title = {Anti-counterfeiting methods},
author = {Joanna Aizenberg and Ximin He and Sung Hoon Kang and Tak-Sing Wong},
year = {2013},
date = {2013-05-31},
note = {U.S. Patent No. 9,937,743 B2},
keywords = {},
pubstate = {published},
tppubtype = {techreport}
}
4.
Grinthal, Alison; Kang, Sung Hoon; Epstein, Alexander K.; Aizenberg, Michael; Khan, Mughees; Aizenberg, Joanna
Steering Nanofibers: An Integrative Approach to Bio-Inspired Fiber Fabrication and Assembly Journal Article
In: Nano Today, vol. 7, pp. 35-52, 2012, (Invited Review).
@article{Grinthal2012,
title = {Steering Nanofibers: An Integrative Approach to Bio-Inspired Fiber Fabrication and Assembly},
author = {Alison Grinthal and Sung Hoon Kang and Alexander K. Epstein and Michael Aizenberg and Mughees Khan and Joanna Aizenberg},
url = {http://www.sciencedirect.com/science/article/pii/S1748013211001411},
year = {2012},
date = {2012-02-01},
journal = {Nano Today},
volume = {7},
pages = {35-52},
abstract = {As seen throughout the natural world, nanoscale fibers exhibit a unique combination of mechanical and surface properties that enable them to wind and bend around each other into an immense diversity of complex forms. In this review, we discuss how this versatility can be harnessed to transform a simple array of anchored nanofibers into a variety of complex, hierarchically organized dynamic functional surfaces. We describe a set of recently developed benchtop techniques that provide a straightforward way to generate libraries of fibrous surfaces with a wide range of finely tuned, nearly arbitrary geometric, mechanical, material, and surface characteristics starting from a single master array. These simple systematic controls can be used to program the fibers to bundle together, twist around each other into chiral swirls, and assemble into patterned arrays of complex hierarchical architectures. The delicate balance between fiber elasticity and surface adhesion plays a critical role in determining the shape, chirality, and higher order of the assembled structures, as does the dynamic evolution of the geometric, mechanical, and surface parameters throughout the assembly process. Hierarchical assembly can also be programmed to run backwards, enabling a wide range of reversible, responsive behaviors to be encoded through rationally chosen surface chemistry. These strategies provide a foundation for designing a vast assortment of functional surfaces with anti-fouling, adhesive, optical, water and ice repellent, memory storage, microfluidic, capture and release, and many more capabilities with the structural and dynamic sophistication of their biological counterparts.},
note = {Invited Review},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
As seen throughout the natural world, nanoscale fibers exhibit a unique combination of mechanical and surface properties that enable them to wind and bend around each other into an immense diversity of complex forms. In this review, we discuss how this versatility can be harnessed to transform a simple array of anchored nanofibers into a variety of complex, hierarchically organized dynamic functional surfaces. We describe a set of recently developed benchtop techniques that provide a straightforward way to generate libraries of fibrous surfaces with a wide range of finely tuned, nearly arbitrary geometric, mechanical, material, and surface characteristics starting from a single master array. These simple systematic controls can be used to program the fibers to bundle together, twist around each other into chiral swirls, and assemble into patterned arrays of complex hierarchical architectures. The delicate balance between fiber elasticity and surface adhesion plays a critical role in determining the shape, chirality, and higher order of the assembled structures, as does the dynamic evolution of the geometric, mechanical, and surface parameters throughout the assembly process. Hierarchical assembly can also be programmed to run backwards, enabling a wide range of reversible, responsive behaviors to be encoded through rationally chosen surface chemistry. These strategies provide a foundation for designing a vast assortment of functional surfaces with anti-fouling, adhesive, optical, water and ice repellent, memory storage, microfluidic, capture and release, and many more capabilities with the structural and dynamic sophistication of their biological counterparts.
5.
Aizenberg, Joanna; Aizenberg, Michael; Kang, Sung Hoon; Kim, Philseok; Tang, Kam Yan; Wong, Tak- Sing
Slippery Surfaces with High Pressure Stability, Optical Transparency, and Self-Healing Characteristics Technical Report
2012, (United States Patent 9,121,306 and 9,121,307).
@techreport{Aizenberg2012b,
title = {Slippery Surfaces with High Pressure Stability, Optical Transparency, and Self-Healing Characteristics},
author = {Joanna Aizenberg and Michael Aizenberg and Sung Hoon Kang and Philseok Kim and Kam Yan Tang and Tak- Sing Wong},
url = {http://www.google.com/patents/US9121306},
year = {2012},
date = {2012-01-19},
note = {United States Patent 9,121,306 and 9,121,307},
keywords = {},
pubstate = {published},
tppubtype = {techreport}
}
6.
Kang, Sung Hoon; Pokroy, Boaz; Mahadevan, L.; Aizenberg, Joanna
Control of Shape and Size of Nanopillar Assembly by Adhesion-Mediated Elastocapillary Interaction Journal Article
In: ACS Nano, vol. 4, pp. 6323–6331, 2010, (Featured on the cover and highlighted in the issue.).
@article{Kang2010,
title = {Control of Shape and Size of Nanopillar Assembly by Adhesion-Mediated Elastocapillary Interaction},
author = {Sung Hoon Kang and Boaz Pokroy and L. Mahadevan and Joanna Aizenberg},
url = {http://pubs.acs.org/doi/abs/10.1021/nn102260t},
year = {2010},
date = {2010-11-01},
journal = {ACS Nano},
volume = {4},
pages = {6323–6331},
abstract = {Control of self-organization of nanofibers into regular clusters upon evaporation-induced assembly is receiving increasing attention due to the potential importance of this process in a range of applications including particle trapping, adhesives, and structural color. Here we present a comprehensive study of this phenomenon using a periodic array of polymeric nanopillars with tunable parameters as a model system to study how geometry, mechanical properties, as well as surface properties influence capillary-induced self-organization. In particular, we show that varying the parameters of the building blocks of self-assembly provides us with a simple means of controlling the size, chirality, and anisotropy of complex structures. We observe that chiral assemblies can be generated within a narrow window for each parameter even in the absence of chiral building blocks or a chiral environment. Furthermore, introducing anisotropy in the building blocks provides a way to control both the chirality and the size of the assembly. While capillary-induced self-assembly has been studied and modeled as a quasi-static process involving the competition between only capillary and elastic forces, our results unequivocally show that both adhesion and kinetics are equally important in determining the final assembly. Our findings provide insight into how multiple parameters work together in capillary-induced self-assembly and provide us with a diverse set of options for fabricating a variety of nanostructures by self-assembly.},
note = {Featured on the cover and highlighted in the issue.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Control of self-organization of nanofibers into regular clusters upon evaporation-induced assembly is receiving increasing attention due to the potential importance of this process in a range of applications including particle trapping, adhesives, and structural color. Here we present a comprehensive study of this phenomenon using a periodic array of polymeric nanopillars with tunable parameters as a model system to study how geometry, mechanical properties, as well as surface properties influence capillary-induced self-organization. In particular, we show that varying the parameters of the building blocks of self-assembly provides us with a simple means of controlling the size, chirality, and anisotropy of complex structures. We observe that chiral assemblies can be generated within a narrow window for each parameter even in the absence of chiral building blocks or a chiral environment. Furthermore, introducing anisotropy in the building blocks provides a way to control both the chirality and the size of the assembly. While capillary-induced self-assembly has been studied and modeled as a quasi-static process involving the competition between only capillary and elastic forces, our results unequivocally show that both adhesion and kinetics are equally important in determining the final assembly. Our findings provide insight into how multiple parameters work together in capillary-induced self-assembly and provide us with a diverse set of options for fabricating a variety of nanostructures by self-assembly.
7.
Pokroy, Boaz; Kang, Sung Hoon; Mahadevan, L.; Aizenberg, Joanna
Self-Organization of a Mesoscale Bristle into Ordered, Hierarchical Helical Assemblies Journal Article
In: Science, vol. 323, pp. 237-240, 2009, (Highlighted in the issue, and various media including New York Times, NPR, Discovery, AAAS EurekAlert, C&EN, Technology Review, IEEE Spectrum, Science Daily, and New Scientist. ).
@article{Pokroy2009,
title = {Self-Organization of a Mesoscale Bristle into Ordered, Hierarchical Helical Assemblies},
author = {Boaz Pokroy and Sung Hoon Kang and L. Mahadevan and Joanna Aizenberg
},
url = {http://www.sciencemag.org/content/323/5911/237.short},
year = {2009},
date = {2009-01-09},
journal = {Science},
volume = {323},
pages = {237-240},
abstract = {Mesoscale hierarchical helical structures with diverse functions are abundant in nature. Here we show how spontaneous helicity can be induced in a synthetic polymeric nanobristle assembling in an evaporating liquid. We use a simple theoretical model to characterize the geometry, stiffness, and surface properties of the pillars that favor the adhesive self-organization of bundles with pillars wound around each other. The process can be controlled to yield highly ordered helical clusters with a unique structural hierarchy that arises from the sequential assembly of self-similar coiled building blocks over multiple length scales. We demonstrate their function in the context of self-assembly into previously unseen structures with uniform, periodic patterns and controlled handedness and as an efficient particle-trapping and adhesive system. },
note = {Highlighted in the issue, and various media including New York Times, NPR, Discovery, AAAS EurekAlert, C&EN, Technology Review, IEEE Spectrum, Science Daily, and New Scientist. },
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Mesoscale hierarchical helical structures with diverse functions are abundant in nature. Here we show how spontaneous helicity can be induced in a synthetic polymeric nanobristle assembling in an evaporating liquid. We use a simple theoretical model to characterize the geometry, stiffness, and surface properties of the pillars that favor the adhesive self-organization of bundles with pillars wound around each other. The process can be controlled to yield highly ordered helical clusters with a unique structural hierarchy that arises from the sequential assembly of self-similar coiled building blocks over multiple length scales. We demonstrate their function in the context of self-assembly into previously unseen structures with uniform, periodic patterns and controlled handedness and as an efficient particle-trapping and adhesive system.
Note: Send e-mail to Prof. Kang at [email protected] if you need a pdf file of the papers below.
2020
Orrego, Santiago; Chen, Zhezhi; Krekora, Urszula; Hou, Decheng; Jeon, Seung‐Yeol; Pittman, Matthew; Montoya, Carolina; Chen, Yun; Kang, Sung Hoon
Bioinspired Materials with Self‐Adaptable Mechanical Properties Journal Article
In: Advanced Materials, 2020.
Abstract | Links | BibTeX | Tags: adaptive, Bio-Inspired, bio-inspired science and engineering, biomaterial, mechanics of soft materials and structures, mineral, multifunctional material, piezoelectric, porous structure, regeneration
@article{Orrego2020,
title = {Bioinspired Materials with Self‐Adaptable Mechanical Properties},
author = {Santiago Orrego and Zhezhi Chen and Urszula Krekora and Decheng Hou and Seung‐Yeol Jeon and Matthew Pittman and Carolina Montoya and Yun Chen and Sung Hoon Kang},
url = {https://onlinelibrary.wiley.com/doi/full/10.1002/adma.201906970},
doi = {https://doi.org/10.1002/adma.201906970},
year = {2020},
date = {2020-04-17},
journal = {Advanced Materials},
abstract = {Natural structural materials, such as bone, can autonomously modulate their mechanical properties in response to external loading to prevent failure. These material systems smartly control the addition/removal of material in locations of high/low mechanical stress by utilizing local resources guided by biological signals. On the contrary, synthetic structural materials have unchanging mechanical properties limiting their mechanical performance and service life. Inspired by the mineralization process of bone, a material system that adapts its mechanical properties in response to external mechanical loading is reported. It is found that charges from piezoelectric scaffolds can induce mineralization from surrounding media. It is shown that the material system can adapt to external mechanical loading by inducing mineral deposition in proportion to the magnitude of the stress and the resulting piezoelectric charges. Moreover, the mineralization mechanism allows a simple one‐step route for fabricating functionally graded materials by controlling the stress distribution along the scaffold. The findings can pave the way for a new class of self‐regenerating materials that reinforce regions of high stress or induce deposition of minerals on the damaged areas from the increase in mechanical stress to prevent/mitigate failure. It is envisioned that the findings can contribute to addressing the current challenges of synthetic materials for load‐bearing applications from self‐adaptive capabilities.},
keywords = {adaptive, Bio-Inspired, bio-inspired science and engineering, biomaterial, mechanics of soft materials and structures, mineral, multifunctional material, piezoelectric, porous structure, regeneration},
pubstate = {published},
tppubtype = {article}
}
Natural structural materials, such as bone, can autonomously modulate their mechanical properties in response to external loading to prevent failure. These material systems smartly control the addition/removal of material in locations of high/low mechanical stress by utilizing local resources guided by biological signals. On the contrary, synthetic structural materials have unchanging mechanical properties limiting their mechanical performance and service life. Inspired by the mineralization process of bone, a material system that adapts its mechanical properties in response to external mechanical loading is reported. It is found that charges from piezoelectric scaffolds can induce mineralization from surrounding media. It is shown that the material system can adapt to external mechanical loading by inducing mineral deposition in proportion to the magnitude of the stress and the resulting piezoelectric charges. Moreover, the mineralization mechanism allows a simple one‐step route for fabricating functionally graded materials by controlling the stress distribution along the scaffold. The findings can pave the way for a new class of self‐regenerating materials that reinforce regions of high stress or induce deposition of minerals on the damaged areas from the increase in mechanical stress to prevent/mitigate failure. It is envisioned that the findings can contribute to addressing the current challenges of synthetic materials for load‐bearing applications from self‐adaptive capabilities.
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}
}
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.
2013
Aizenberg, Joanna; He, Ximin; Kang, Sung Hoon; Wong, Tak-Sing
Anti-counterfeiting methods Technical Report
2013, (U.S. Patent No. 9,937,743 B2).
BibTeX | Tags: bio-inspired science and engineering, Reconfigurable, Security, Structured Surfaces
@techreport{Aizenberg2012,
title = {Anti-counterfeiting methods},
author = {Joanna Aizenberg and Ximin He and Sung Hoon Kang and Tak-Sing Wong},
year = {2013},
date = {2013-05-31},
note = {U.S. Patent No. 9,937,743 B2},
keywords = {bio-inspired science and engineering, Reconfigurable, Security, Structured Surfaces},
pubstate = {published},
tppubtype = {techreport}
}
2012
Grinthal, Alison; Kang, Sung Hoon; Epstein, Alexander K.; Aizenberg, Michael; Khan, Mughees; Aizenberg, Joanna
Steering Nanofibers: An Integrative Approach to Bio-Inspired Fiber Fabrication and Assembly Journal Article
In: Nano Today, vol. 7, pp. 35-52, 2012, (Invited Review).
Abstract | Links | BibTeX | Tags: Assembly, Bio-Inspired, bio-inspired science and engineering, Chemistry, Fabrication, Geometry, Hierarchical, Mechanics, Nanofiber, Symmetry
@article{Grinthal2012,
title = {Steering Nanofibers: An Integrative Approach to Bio-Inspired Fiber Fabrication and Assembly},
author = {Alison Grinthal and Sung Hoon Kang and Alexander K. Epstein and Michael Aizenberg and Mughees Khan and Joanna Aizenberg},
url = {http://www.sciencedirect.com/science/article/pii/S1748013211001411},
year = {2012},
date = {2012-02-01},
journal = {Nano Today},
volume = {7},
pages = {35-52},
abstract = {As seen throughout the natural world, nanoscale fibers exhibit a unique combination of mechanical and surface properties that enable them to wind and bend around each other into an immense diversity of complex forms. In this review, we discuss how this versatility can be harnessed to transform a simple array of anchored nanofibers into a variety of complex, hierarchically organized dynamic functional surfaces. We describe a set of recently developed benchtop techniques that provide a straightforward way to generate libraries of fibrous surfaces with a wide range of finely tuned, nearly arbitrary geometric, mechanical, material, and surface characteristics starting from a single master array. These simple systematic controls can be used to program the fibers to bundle together, twist around each other into chiral swirls, and assemble into patterned arrays of complex hierarchical architectures. The delicate balance between fiber elasticity and surface adhesion plays a critical role in determining the shape, chirality, and higher order of the assembled structures, as does the dynamic evolution of the geometric, mechanical, and surface parameters throughout the assembly process. Hierarchical assembly can also be programmed to run backwards, enabling a wide range of reversible, responsive behaviors to be encoded through rationally chosen surface chemistry. These strategies provide a foundation for designing a vast assortment of functional surfaces with anti-fouling, adhesive, optical, water and ice repellent, memory storage, microfluidic, capture and release, and many more capabilities with the structural and dynamic sophistication of their biological counterparts.},
note = {Invited Review},
keywords = {Assembly, Bio-Inspired, bio-inspired science and engineering, Chemistry, Fabrication, Geometry, Hierarchical, Mechanics, Nanofiber, Symmetry},
pubstate = {published},
tppubtype = {article}
}
As seen throughout the natural world, nanoscale fibers exhibit a unique combination of mechanical and surface properties that enable them to wind and bend around each other into an immense diversity of complex forms. In this review, we discuss how this versatility can be harnessed to transform a simple array of anchored nanofibers into a variety of complex, hierarchically organized dynamic functional surfaces. We describe a set of recently developed benchtop techniques that provide a straightforward way to generate libraries of fibrous surfaces with a wide range of finely tuned, nearly arbitrary geometric, mechanical, material, and surface characteristics starting from a single master array. These simple systematic controls can be used to program the fibers to bundle together, twist around each other into chiral swirls, and assemble into patterned arrays of complex hierarchical architectures. The delicate balance between fiber elasticity and surface adhesion plays a critical role in determining the shape, chirality, and higher order of the assembled structures, as does the dynamic evolution of the geometric, mechanical, and surface parameters throughout the assembly process. Hierarchical assembly can also be programmed to run backwards, enabling a wide range of reversible, responsive behaviors to be encoded through rationally chosen surface chemistry. These strategies provide a foundation for designing a vast assortment of functional surfaces with anti-fouling, adhesive, optical, water and ice repellent, memory storage, microfluidic, capture and release, and many more capabilities with the structural and dynamic sophistication of their biological counterparts.
Aizenberg, Joanna; Aizenberg, Michael; Kang, Sung Hoon; Kim, Philseok; Tang, Kam Yan; Wong, Tak- Sing
Slippery Surfaces with High Pressure Stability, Optical Transparency, and Self-Healing Characteristics Technical Report
2012, (United States Patent 9,121,306 and 9,121,307).
Links | BibTeX | Tags: Anti-stiction, bio-inspired science and engineering, Coating, High Pressure, Ice-repellent, Oil-repellent, Optical Transparency, Self-Repair, Slippery
@techreport{Aizenberg2012b,
title = {Slippery Surfaces with High Pressure Stability, Optical Transparency, and Self-Healing Characteristics},
author = {Joanna Aizenberg and Michael Aizenberg and Sung Hoon Kang and Philseok Kim and Kam Yan Tang and Tak- Sing Wong},
url = {http://www.google.com/patents/US9121306},
year = {2012},
date = {2012-01-19},
note = {United States Patent 9,121,306 and 9,121,307},
keywords = {Anti-stiction, bio-inspired science and engineering, Coating, High Pressure, Ice-repellent, Oil-repellent, Optical Transparency, Self-Repair, Slippery},
pubstate = {published},
tppubtype = {techreport}
}
2010
Kang, Sung Hoon; Pokroy, Boaz; Mahadevan, L.; Aizenberg, Joanna
Control of Shape and Size of Nanopillar Assembly by Adhesion-Mediated Elastocapillary Interaction Journal Article
In: ACS Nano, vol. 4, pp. 6323–6331, 2010, (Featured on the cover and highlighted in the issue.).
Abstract | Links | BibTeX | Tags: Adhesion, bio-inspired science and engineering, Elastocapillary, Evaporation, Nanopillar, Patterning, Self-Organization
@article{Kang2010,
title = {Control of Shape and Size of Nanopillar Assembly by Adhesion-Mediated Elastocapillary Interaction},
author = {Sung Hoon Kang and Boaz Pokroy and L. Mahadevan and Joanna Aizenberg},
url = {http://pubs.acs.org/doi/abs/10.1021/nn102260t},
year = {2010},
date = {2010-11-01},
journal = {ACS Nano},
volume = {4},
pages = {6323–6331},
abstract = {Control of self-organization of nanofibers into regular clusters upon evaporation-induced assembly is receiving increasing attention due to the potential importance of this process in a range of applications including particle trapping, adhesives, and structural color. Here we present a comprehensive study of this phenomenon using a periodic array of polymeric nanopillars with tunable parameters as a model system to study how geometry, mechanical properties, as well as surface properties influence capillary-induced self-organization. In particular, we show that varying the parameters of the building blocks of self-assembly provides us with a simple means of controlling the size, chirality, and anisotropy of complex structures. We observe that chiral assemblies can be generated within a narrow window for each parameter even in the absence of chiral building blocks or a chiral environment. Furthermore, introducing anisotropy in the building blocks provides a way to control both the chirality and the size of the assembly. While capillary-induced self-assembly has been studied and modeled as a quasi-static process involving the competition between only capillary and elastic forces, our results unequivocally show that both adhesion and kinetics are equally important in determining the final assembly. Our findings provide insight into how multiple parameters work together in capillary-induced self-assembly and provide us with a diverse set of options for fabricating a variety of nanostructures by self-assembly.},
note = {Featured on the cover and highlighted in the issue.},
keywords = {Adhesion, bio-inspired science and engineering, Elastocapillary, Evaporation, Nanopillar, Patterning, Self-Organization},
pubstate = {published},
tppubtype = {article}
}
Control of self-organization of nanofibers into regular clusters upon evaporation-induced assembly is receiving increasing attention due to the potential importance of this process in a range of applications including particle trapping, adhesives, and structural color. Here we present a comprehensive study of this phenomenon using a periodic array of polymeric nanopillars with tunable parameters as a model system to study how geometry, mechanical properties, as well as surface properties influence capillary-induced self-organization. In particular, we show that varying the parameters of the building blocks of self-assembly provides us with a simple means of controlling the size, chirality, and anisotropy of complex structures. We observe that chiral assemblies can be generated within a narrow window for each parameter even in the absence of chiral building blocks or a chiral environment. Furthermore, introducing anisotropy in the building blocks provides a way to control both the chirality and the size of the assembly. While capillary-induced self-assembly has been studied and modeled as a quasi-static process involving the competition between only capillary and elastic forces, our results unequivocally show that both adhesion and kinetics are equally important in determining the final assembly. Our findings provide insight into how multiple parameters work together in capillary-induced self-assembly and provide us with a diverse set of options for fabricating a variety of nanostructures by self-assembly.
2009
Pokroy, Boaz; Kang, Sung Hoon; Mahadevan, L.; Aizenberg, Joanna
Self-Organization of a Mesoscale Bristle into Ordered, Hierarchical Helical Assemblies Journal Article
In: Science, vol. 323, pp. 237-240, 2009, (Highlighted in the issue, and various media including New York Times, NPR, Discovery, AAAS EurekAlert, C&EN, Technology Review, IEEE Spectrum, Science Daily, and New Scientist. ).
Abstract | Links | BibTeX | Tags: bio-inspired science and engineering, Helical, Hierarchical, Mesoscale, Nanopillar, Order, Self-Organization
@article{Pokroy2009,
title = {Self-Organization of a Mesoscale Bristle into Ordered, Hierarchical Helical Assemblies},
author = {Boaz Pokroy and Sung Hoon Kang and L. Mahadevan and Joanna Aizenberg
},
url = {http://www.sciencemag.org/content/323/5911/237.short},
year = {2009},
date = {2009-01-09},
journal = {Science},
volume = {323},
pages = {237-240},
abstract = {Mesoscale hierarchical helical structures with diverse functions are abundant in nature. Here we show how spontaneous helicity can be induced in a synthetic polymeric nanobristle assembling in an evaporating liquid. We use a simple theoretical model to characterize the geometry, stiffness, and surface properties of the pillars that favor the adhesive self-organization of bundles with pillars wound around each other. The process can be controlled to yield highly ordered helical clusters with a unique structural hierarchy that arises from the sequential assembly of self-similar coiled building blocks over multiple length scales. We demonstrate their function in the context of self-assembly into previously unseen structures with uniform, periodic patterns and controlled handedness and as an efficient particle-trapping and adhesive system. },
note = {Highlighted in the issue, and various media including New York Times, NPR, Discovery, AAAS EurekAlert, C&EN, Technology Review, IEEE Spectrum, Science Daily, and New Scientist. },
keywords = {bio-inspired science and engineering, Helical, Hierarchical, Mesoscale, Nanopillar, Order, Self-Organization},
pubstate = {published},
tppubtype = {article}
}
Mesoscale hierarchical helical structures with diverse functions are abundant in nature. Here we show how spontaneous helicity can be induced in a synthetic polymeric nanobristle assembling in an evaporating liquid. We use a simple theoretical model to characterize the geometry, stiffness, and surface properties of the pillars that favor the adhesive self-organization of bundles with pillars wound around each other. The process can be controlled to yield highly ordered helical clusters with a unique structural hierarchy that arises from the sequential assembly of self-similar coiled building blocks over multiple length scales. We demonstrate their function in the context of self-assembly into previously unseen structures with uniform, periodic patterns and controlled handedness and as an efficient particle-trapping and adhesive system.