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Michigan Technological University
1.
Narkar, Ameya R.
REVERSIBLY SWITCHING ADHESION OF SMART ADHESIVES INSPIRED BY MUSSEL ADHESIVE CHEMISTRY.
Degree: PhD, Department of Biomedical Engineering, 2018, Michigan Technological University
URL: https://digitalcommons.mtu.edu/etdr/741 
► Catecholic groups in mussel adhesive proteins transition from being strongly adhesive in a reduced state under acidic conditions to being weakly adhesive in an…
(more)
▼ Catecholic groups in mussel adhesive proteins transition from being strongly adhesive in a reduced state under acidic conditions to being weakly adhesive in an oxidized state under basic conditions. Here, we exploit this pH responsive behavior of catechol and demonstrate that its oxidation state can be manipulated by incorporation of boronic acid to facilitate
reversible transitions between strong and weak
adhesion. Our first approach involved the addition of 3- acrylamido phenylboronic acid (APBA) to dopamine methacrylamide (DMA) containing adhesives. The synthesized adhesives showed strong
adhesion to quartz surface in an acidic medium (pH 3), while weak
adhesion was observed on raising the pH to a basic value (pH 9), due to unavailability of catechol and boronic acid because of the formation of a
reversible catechol-boronate complex. Boronic acid not only contributed to
adhesion at an acidic pH, but also allowed the catechol to reversibly interact with the surface in response to changing pH. In our second study, we demonstrated that addition of an anionic monomer, acrylic acid (AAc), preserved the reduced and adhesive state of catechol even at a neutral to mildly basic pH, while the addition of a cationic monomer, N-(aminopropyl) methacrylamide hydrochloride, led to the oxidized and weak adhesive state at higher basic pH values. This was due to the buffering of local pH offered by the incorporation of the ionic species, which affected the oxidation state of catechol. Although the ideal pH for formation of the complex is 9, it readily forms at neutral to mildly basic pH, leading to decreased
adhesion and limiting the adhesive’s application in physiological and marine pH environments. In our third 2 approach, adding elevated amounts of AAc to smart adhesives consisting of DMA and APBA led to strong
adhesion to quartz substrate at neutral to mildly basic pH. Moreover, the complex formed at pH 9 remained
reversible and the interfacial binding could be tuned by changing the pH during successive contact cycles. pH 3 was required to break the complex and recover the strong adhesive property. Bulk adhesives analyzed in our first three approaches needed extended periods of incubation (up to 30 min) to switch between their adhesive and non-adhesive states. This is because infiltration of the pH media into the bulk polymer is limited by the slow process of diffusion. Finally, we fabricated a hybrid adhesive which was composed of gecko-inspired microstructured PDMS pillars (aspect ratios of 0.4-2) coated with the smart adhesive that we developed in our first approach. By tuning the aspect ratio of the bare templates, hybrid structures that showed strong, elevated
adhesion at pH 3, were obtained. The increased
adhesion was attributed to contact-splitting effects due to the micropatterning combined with the interfacial binding of the smart adhesive. On the other hand, formation of the complex, and the associated swelling of the adhesive together contributed to a significant decrease in
adhesion at pH 9. Additionally, the…
Advisors/Committee Members: Bruce P. Lee.
Subjects/Keywords: Mussel Adhesion; Catechol; Reversible adhesion; Smart Adhesive; Rapid adhesion; Biomaterials
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APA (6th Edition):
Narkar, A. R. (2018). REVERSIBLY SWITCHING ADHESION OF SMART ADHESIVES INSPIRED BY MUSSEL ADHESIVE CHEMISTRY. (Doctoral Dissertation). Michigan Technological University. Retrieved from https://digitalcommons.mtu.edu/etdr/741
Chicago Manual of Style (16th Edition):
Narkar, Ameya R. “REVERSIBLY SWITCHING ADHESION OF SMART ADHESIVES INSPIRED BY MUSSEL ADHESIVE CHEMISTRY.” 2018. Doctoral Dissertation, Michigan Technological University. Accessed January 18, 2021.
https://digitalcommons.mtu.edu/etdr/741.
MLA Handbook (7th Edition):
Narkar, Ameya R. “REVERSIBLY SWITCHING ADHESION OF SMART ADHESIVES INSPIRED BY MUSSEL ADHESIVE CHEMISTRY.” 2018. Web. 18 Jan 2021.
Vancouver:
Narkar AR. REVERSIBLY SWITCHING ADHESION OF SMART ADHESIVES INSPIRED BY MUSSEL ADHESIVE CHEMISTRY. [Internet] [Doctoral dissertation]. Michigan Technological University; 2018. [cited 2021 Jan 18].
Available from: https://digitalcommons.mtu.edu/etdr/741.
Council of Science Editors:
Narkar AR. REVERSIBLY SWITCHING ADHESION OF SMART ADHESIVES INSPIRED BY MUSSEL ADHESIVE CHEMISTRY. [Doctoral Dissertation]. Michigan Technological University; 2018. Available from: https://digitalcommons.mtu.edu/etdr/741
2.
Stampfli, Patrick Ryan.
Tunable Reversible Dry Adhesion of Elastomeric Post Enabled by Stiffness Tuning of Microfluidic LMPA Thin Film.
Degree: 2017, University of Nevada – Reno
URL: http://hdl.handle.net/11714/2567
► The goal of this study is to investigate the effects and underlying mechanisms of stiffness tuning on tunable reversible dry adhesion of an elastomeric post.…
(more)
▼ The goal of this study is to investigate the effects and underlying mechanisms of stiffness tuning on tunable
reversible dry
adhesion of an elastomeric post. This research introduces a novel device constructed out of a soft elastomer, polydemethylsiloxane (PDMS), with micro channels injected with low melting point alloy (LMPA) that can soften by applying a voltage. In contrast to traditional handling devices, such as metallic robot handlers, this soft gripper enables compliant manipulation of delicate fragile objects such as a thin glass slide. In this thesis, the design and fabrication of the elastomeric posts and the effects of three
adhesion testing conditions will be presented. The first testing condition provided the baseline
adhesion values that would be later referenced to certify
adhesion reversibility. The second condition demonstrates the device’s ability to change
adhesion forces on the spot, or dynamically. The third condition displays the ability of the device to maintain this
adhesion change when activated and deactivated repeatedly. Theoretical Finite Element modeling provides insights indicating a maximum
adhesion when varying one critical geometrical parameter, which was later confirmed with experiments. Experimental results prove the device’s capability of dynamically tunable
reversible dry
adhesion. This novel approach to tunable dry
adhesion exhibits the feasibility of soft grippers that would not require complicated systems for activation but instead only need low power and simple circuitry, and thus have potential to function as effective soft gripping devices.
Advisors/Committee Members: Shan, Wanliang (advisor), Aureli, Matteo (committee member), LaCombe, Jeffrey (committee member).
Subjects/Keywords: Adhesion; Dry; LMPA; PDMS; Reversible; Tunable
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APA (6th Edition):
Stampfli, P. R. (2017). Tunable Reversible Dry Adhesion of Elastomeric Post Enabled by Stiffness Tuning of Microfluidic LMPA Thin Film. (Thesis). University of Nevada – Reno. Retrieved from http://hdl.handle.net/11714/2567
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Stampfli, Patrick Ryan. “Tunable Reversible Dry Adhesion of Elastomeric Post Enabled by Stiffness Tuning of Microfluidic LMPA Thin Film.” 2017. Thesis, University of Nevada – Reno. Accessed January 18, 2021.
http://hdl.handle.net/11714/2567.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Stampfli, Patrick Ryan. “Tunable Reversible Dry Adhesion of Elastomeric Post Enabled by Stiffness Tuning of Microfluidic LMPA Thin Film.” 2017. Web. 18 Jan 2021.
Vancouver:
Stampfli PR. Tunable Reversible Dry Adhesion of Elastomeric Post Enabled by Stiffness Tuning of Microfluidic LMPA Thin Film. [Internet] [Thesis]. University of Nevada – Reno; 2017. [cited 2021 Jan 18].
Available from: http://hdl.handle.net/11714/2567.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Stampfli PR. Tunable Reversible Dry Adhesion of Elastomeric Post Enabled by Stiffness Tuning of Microfluidic LMPA Thin Film. [Thesis]. University of Nevada – Reno; 2017. Available from: http://hdl.handle.net/11714/2567
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Toronto
3.
Laqua, Kurtis.
Dynamic Microtopography Arrays for Hybrid and Adaptive Switchable Adhesion.
Degree: 2019, University of Toronto
URL: http://hdl.handle.net/1807/102975
► The feet of many insects contain both a ‘sticky’ pad and sharp claws that can be intelligently actuated to ‘switch’ (on/off) their adhesion to smooth…
(more)
▼ The feet of many insects contain both a ‘sticky’ pad and sharp claws that can be intelligently actuated to ‘switch’ (on/off) their adhesion to smooth and rough surfaces, respectively. In contrast, synthetic switchable adhesives designs are mechanistically simple and unable to adapt to real-world surfaces. This work proposes a bio-inspired hybrid (multi-mechanistic) and adaptive device that can control adhesion and friction on both smooth and rough surfaces. A novel pneumatic smart surface is designed that both actuates (rotates) multifunctional adhesive microtopography and provides sensory feedback at multiple independent areas on the surface. It will be shown that by rotating topography, the surface can switch between sticky and non-sticky states (99.3% reduction) and can also interlock with holes and protrusions (asperities) of rough surfaces. Through integrated and external sensory feedback combined local control, the device can sense adhesion loss, surface contact, and ultimately develop localized adhesive strategies that optimise global adhesion.
M.A.S.
2020-11-20 00:00:00
Advisors/Committee Members: Hatton, Benjamin D, Materials Science and Engineering.
Subjects/Keywords: Adaptive; Bio-inspiration; Hybrid; Reversible Adhesion; Soft Robotics; Switchable Adhesion; 0794
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APA (6th Edition):
Laqua, K. (2019). Dynamic Microtopography Arrays for Hybrid and Adaptive Switchable Adhesion. (Masters Thesis). University of Toronto. Retrieved from http://hdl.handle.net/1807/102975
Chicago Manual of Style (16th Edition):
Laqua, Kurtis. “Dynamic Microtopography Arrays for Hybrid and Adaptive Switchable Adhesion.” 2019. Masters Thesis, University of Toronto. Accessed January 18, 2021.
http://hdl.handle.net/1807/102975.
MLA Handbook (7th Edition):
Laqua, Kurtis. “Dynamic Microtopography Arrays for Hybrid and Adaptive Switchable Adhesion.” 2019. Web. 18 Jan 2021.
Vancouver:
Laqua K. Dynamic Microtopography Arrays for Hybrid and Adaptive Switchable Adhesion. [Internet] [Masters thesis]. University of Toronto; 2019. [cited 2021 Jan 18].
Available from: http://hdl.handle.net/1807/102975.
Council of Science Editors:
Laqua K. Dynamic Microtopography Arrays for Hybrid and Adaptive Switchable Adhesion. [Masters Thesis]. University of Toronto; 2019. Available from: http://hdl.handle.net/1807/102975
4.
,Abdul Wasay.
Geckofluidics: A strong and reliable reversible bonding
technique for microfluidics.
Degree: MS, Department of Mechanical Engineering, 2016, University of Alberta
URL: https://era.library.ualberta.ca/files/c2801pg371
► Towards minimizing the cost of Micro Total Analysis Systems(µTAS) or Lab on a chip (LoC) systems, it is important to minimize manufacturing and assembly cost…
(more)
▼ Towards minimizing the cost of Micro Total Analysis
Systems(µTAS) or Lab on a chip (LoC) systems, it is important to
minimize manufacturing and assembly cost and time, and lower
material costs. While the choice of material does govern material
costs and the manufacturing process required and thereby, the time,
it has been observed that the assembly(bonding) and interfacing
time is one of the major rate limiting stepsfor the entire process.
This work is an attempt to introduce a new bonding technique for
microfluidics by using synthetic gecko inspired adhesives. This
technique is being referred to as Geckofluidics. It doesn’t require
the use of any solvents or glues or surface activation or
application of high pressure and/or temperature and is achievable
in a process which doesn’t require any additional equipment or add
to the cost. It provides for a strong and reliable, reversible
bonding technique, with bond strengths being on par with
traditional irreversible bond strengths in elastomers. This work
characterizes the manufacturing feasibility of geckofluidic devices
with various thermoplastic elastomers. A finite element simulation
was also implemented inorder to study the effect of some of the
remedial measures taken to improve the adhesion strength, and also
to study the minimum number of adhesive features required to
effectively support the integration with microfluidics.A rapid mass
manufacturing technique is also demonstrated using
thermocompressive molding in thermoplastic elastomers. The
resulting devices have been demonstrated for use for both
pressurized and non-pressurized microfluidic systems against
various substrates.
Subjects/Keywords: Gecko inspired adhesives; microfluidic chip bonding; reversible adhesion; Microfluidics
…70
Fig. 31. Fiber geometries tested for maximum adhesion strength… …incompatible in the presence of pre-patterned biological reagents[31, 32],
Reversible… …these challenges a strong yet reliable reversible bonding
technique is desired. This work… …microfluidics. A brief insight into Gecko Adhesion will
help us understand the solutions at hand.
1.4… …Gecko Adhesion:
Geckos can stick to arbitrary surfaces purely by van der Waals intermolecular…
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APA ·
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APA (6th Edition):
Wasay, ,. (2016). Geckofluidics: A strong and reliable reversible bonding
technique for microfluidics. (Masters Thesis). University of Alberta. Retrieved from https://era.library.ualberta.ca/files/c2801pg371
Chicago Manual of Style (16th Edition):
Wasay, ,Abdul. “Geckofluidics: A strong and reliable reversible bonding
technique for microfluidics.” 2016. Masters Thesis, University of Alberta. Accessed January 18, 2021.
https://era.library.ualberta.ca/files/c2801pg371.
MLA Handbook (7th Edition):
Wasay, ,Abdul. “Geckofluidics: A strong and reliable reversible bonding
technique for microfluidics.” 2016. Web. 18 Jan 2021.
Vancouver:
Wasay ,. Geckofluidics: A strong and reliable reversible bonding
technique for microfluidics. [Internet] [Masters thesis]. University of Alberta; 2016. [cited 2021 Jan 18].
Available from: https://era.library.ualberta.ca/files/c2801pg371.
Council of Science Editors:
Wasay ,. Geckofluidics: A strong and reliable reversible bonding
technique for microfluidics. [Masters Thesis]. University of Alberta; 2016. Available from: https://era.library.ualberta.ca/files/c2801pg371
5.
Bartlett, Michael David.
Scaling Reversible Adhesion in Synthetic and Biological Systems.
Degree: PhD, Polymer Science and Engineering, 2013, U of Massachusetts : PhD
URL: https://scholarworks.umass.edu/open_access_dissertations/834
► Geckos and other insects have fascinated scientists and casual observers with their ability to effortlessly climb up walls and across ceilings. This capability has…
(more)
▼ Geckos and other insects have fascinated scientists and casual observers with their ability to effortlessly climb up walls and across ceilings. This capability has inspired high capacity, easy release synthetic adhesives, which have focused on mimicking the fibrillar features found on the foot pads of these climbing organisms. However, without a fundamental framework that connects biological and synthetic adhesives from nanoscopic to macroscopic features, synthetic mimics have failed to perform favorably at large contact areas. In this thesis, we present a scaling approach which leads to an understanding of
reversible adhesion in both synthetic and biological systems over multiple length scales. We identify, under various loading scenarios, how geometry and material properties control
adhesion, and we apply this understanding to the development of high capacity, easy release synthetic adhesive materials at macroscopic size scales.
Starting from basic fracture mechanics, our generalized scaling theory reveals that the ratio of contact area to compliance in the loading direction,
A/C, is the governing scaling parameter for the force capacity of
reversible adhesive interfaces. This scaling theory is verified experimentally in both synthetic and biological adhesive systems, over many orders of magnitude in size and adhesive force capacity (Chapter 2). This understanding is applied to the development of gecko-like adhesive pads, consisting of stiff, draping fabrics incorporated with thin elastomeric layers, which at macroscopic sizes (contact areas of 100 cm2) exhibit force capacities on the order of 3000 N. Significantly, this adhesive pad is non-patterned and completely smooth, demonstrating that fibrillar features are not necessary to achieve high capacity, easy release
adhesion at macroscopic sizes and emphasizing the importance of subsurface anatomy in biological adhesive systems (Chapter 2, Chapter 3).
We further extend the utility of the scaling theory under shear (Chapter 4) and normal (Chapter 5) loading conditions and develop simple expressions for patterned and non-patterned interfaces which describe experimental force capacity data as a function of geometric parameters such as contact area, aspect ratio, and contact radius. These studies provide guidance for the precise control of
adhesion with enables the development of a simple transfer printing technique controlled by geometric confinement (Chapter 6). Force capacity data from each chapter, along with various literature data are collapsed onto a master plot described by the
A/C scaling parameter, with agreement over 15 orders of magnitude in adhesive force capacity for synthetic and biological adhesives, demonstrating the generality and robustness of the scaling theory (Chapter 7).
Advisors/Committee Members: Alfred J. Crosby, Alan J. Lesser, Duncan J. Irschick.
Subjects/Keywords: Adhesion; Bio-Inspired; Gecko; Geckskin; Reversible Adhesion; Scaling; Applied Mechanics; Other Engineering; Polymer Science
…nothing more.
viii
ABSTRACT
SCALING REVERSIBLE ADHESION IN SYNTHETIC AND BIOLOGICAL SYSTEMS… …present a scaling approach which leads to an
understanding of reversible adhesion in both… …26
2.4
2.5
2.3.1
Derivation of the Reversible Adhesion Scaling Relationship… …Adhesion Society for years to come. I thank Sam Pendergraph, who
was never afraid to ask a… …for all of the adhesion work and good times we had
together, Dan is a true friend and…
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APA ·
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Manager
APA (6th Edition):
Bartlett, M. D. (2013). Scaling Reversible Adhesion in Synthetic and Biological Systems. (Doctoral Dissertation). U of Massachusetts : PhD. Retrieved from https://scholarworks.umass.edu/open_access_dissertations/834
Chicago Manual of Style (16th Edition):
Bartlett, Michael David. “Scaling Reversible Adhesion in Synthetic and Biological Systems.” 2013. Doctoral Dissertation, U of Massachusetts : PhD. Accessed January 18, 2021.
https://scholarworks.umass.edu/open_access_dissertations/834.
MLA Handbook (7th Edition):
Bartlett, Michael David. “Scaling Reversible Adhesion in Synthetic and Biological Systems.” 2013. Web. 18 Jan 2021.
Vancouver:
Bartlett MD. Scaling Reversible Adhesion in Synthetic and Biological Systems. [Internet] [Doctoral dissertation]. U of Massachusetts : PhD; 2013. [cited 2021 Jan 18].
Available from: https://scholarworks.umass.edu/open_access_dissertations/834.
Council of Science Editors:
Bartlett MD. Scaling Reversible Adhesion in Synthetic and Biological Systems. [Doctoral Dissertation]. U of Massachusetts : PhD; 2013. Available from: https://scholarworks.umass.edu/open_access_dissertations/834
. 
Open Access Theses and Dissertations
