Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International



Home > Press > How surface roughness influences the adhesion of soft materials: Research team discovers universal mechanism that leads to adhesion hysteresis in soft materials

The simulation shows the contact area of a soft solid that is separated from a rough surface. Each coloured spot corresponds to an instability of the contact. The different colour intensity shows how much energy is lost in the process. 

CREDIT
Antoine Sanner, Lars Pastewka.
The simulation shows the contact area of a soft solid that is separated from a rough surface. Each coloured spot corresponds to an instability of the contact. The different colour intensity shows how much energy is lost in the process. CREDIT Antoine Sanner, Lars Pastewka.

Abstract:
Adhesive tape or sticky notes are easy to attach to a surface, but are difficult to remove. This phenomenon, known as adhesion hysteresis, can be fundamentally observed in soft, elastic materials: Adhesive contact is formed more easily than it is broken. Researchers at the University of Freiburg, the University of Pittsburgh and the University of Akron in the US have now discovered that this adhesion hysteresis is caused by the surface roughness of the adherent soft materials. Through a combination of experimental observations and simulations, the team demonstrated that roughness interferes with the separation process, causing the materials to detach in minute, abrupt movements, which release parts of the adhesive bond incrementally. Dr. Antoine Sanner and Prof. Dr. Lars Pastewka from the Department of Microsystems Engineering and the livMatS Cluster of Excellence at the University of Freiburg, Dr. Nityanshu Kumar and Prof. Dr. Ali Dhinojwala from the University of Akron and Prof. Dr. Tevis Jacobs from the University of Pittsburgh have published their results in the prestigious journal Science Advances.

How surface roughness influences the adhesion of soft materials: Research team discovers universal mechanism that leads to adhesion hysteresis in soft materials

Freiburg, Germany | Posted on March 8th, 2024

“Our findings will make it possible to specifically control the adhesion properties of soft materials through surface roughness,” says Sanner. “They will also allow new and improved applications to be developed in soft robotics or production technology in the future, for example for grippers or placement systems.”

Sudden jumping movement of the edge of the contact

Until now, researchers have hypothesized that viscoelastic energy dissipation causes adhesion hysteresis in soft solids. In other words, energy is lost to heat in the material because it deforms in the contact cycle: It is compressed when making contact and expands during release. Those energy losses counteract the movement of the contact surface, which increases the adhesive force during separation. Contact ageing, i.e. the formation of chemical bonds on the contact surface, has also been suggested as a cause. Here the longer the contact exists, the greater the adhesion. “Our simulations show that the observed hysteresis can be explained without these specific energy dissipation mechanisms. The only source of energy dissipation in our numerical model is the sudden jumping movement of the edge of the contact, which is induced by the roughness,” says Sanner.

Adhesion hysteresis calculated for realistic surface roughness

This sudden jumping motion is clearly recognisable in the simulations of the Freiburg researchers and in the adhesion experiments of the University of Akron. “The abrupt change in the contact surface was already mentioned in the 1990s as a possible cause of adhesion hysteresis, but previous theoretical work on this was limited to simplified surface properties," explains Kumar. “We have succeeded for the first time in calculating the adhesion hysteresis for realistic surface roughness. This is based on the efficiency of the numerical model and an extremely detailed surface characterisation carried out by researchers at the University of Pittsburgh,” says Jacobs.



About the Cluster of Excellence livMatS

The vision of the Cluster of Excellence Living, Adaptive, and Energy-Autonomous Materials Systems (livMatS) is to combine the best of both worlds – nature and technology. livMatS develops lifelike materials systems inspired by nature. These systems adapt autonomously to their environment, harvest clean energy from their surroundings, and are insensitive to or able to recover from damage.




•Prof. Dr. Lars Pastewka has been Professor of Simulation at the Faculty of Engineering and a member of the Cluster of Excellence Living, Adaptive and Energy-autonomous Materials Systems (livMatS) at the University of Freiburg since 2017.
•Dr. Antoine Sanner completed his doctorate at the Department of Microsystems Engineering and in the Cluster of Excellence livMatS.
•The study was funded by the German Research Foundation (livMatS - EXC 2193), the European Research Council (StG 757343), the National Science Foundation (DMR-2208464) and the National Institute for Occupational Safety and Health (R21 OH012126).

####

For more information, please click here

Contacts:
Isabelle Mittermeier
University of Freiburg


Office of University and Science Communications
University of Freiburg
Tel.: 0761/203-4302
e-mail:



Sonja Seidel
Science Communications Cluster of Excellence livMatS
University of Freiburg
Tel.: 0761/203-95361

Copyright © University of Freiburg

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related Links

Original publication: Antoine Sanner et al., Sci. Adv. 10, eadl1277 (2024). doi: 10.1126/sciadv.adl1277:

Related News Press

News and information

New method in the fight against forever chemicals September 13th, 2024

Energy transmission in quantum field theory requires information September 13th, 2024

Breakthrough in proton barrier films using pore-free graphene oxide: Kumamoto University researchers achieve new milestone in advanced coating technologies September 13th, 2024

Quantum researchers cause controlled ‘wobble’ in the nucleus of a single atom September 13th, 2024

Possible Futures

Rice research could make weird AI images a thing of the past: New diffusion model approach solves the aspect ratio problem September 13th, 2024

Giving batteries a longer life with the Advanced Photon Source: New research uncovers a hydrogen-centered mechanism that triggers degradation in the lithium-ion batteries that power electric vehicles September 13th, 2024

NYU Abu Dhabi researchers develop novel covalent organic frameworks for precise cancer treatment delivery: NYU Abu Dhabi researchers develop novel covalent organic frameworks for precise cancer treatment delivery September 13th, 2024

New discovery aims to improve the design of microelectronic devices September 13th, 2024

Discoveries

Energy transmission in quantum field theory requires information September 13th, 2024

Breakthrough in proton barrier films using pore-free graphene oxide: Kumamoto University researchers achieve new milestone in advanced coating technologies September 13th, 2024

Quantum researchers cause controlled ‘wobble’ in the nucleus of a single atom September 13th, 2024

New nanomaterial could transform how we visualise fingerprints: Innovative nanomaterials have the potential to revolutionise forensic science, particularly in the detection of latent (non-visible) fingermarks September 13th, 2024

Materials/Metamaterials/Magnetoresistance

Nanoscale CL thermometry with lanthanide-doped heavy-metal oxide in TEM March 8th, 2024

Focused ion beam technology: A single tool for a wide range of applications January 12th, 2024

Catalytic combo converts CO2 to solid carbon nanofibers: Tandem electrocatalytic-thermocatalytic conversion could help offset emissions of potent greenhouse gas by locking carbon away in a useful material January 12th, 2024

Finding the most heat-resistant substances ever made: UVA Engineering secures DOD MURI award to advance high-temperature materials December 8th, 2023

Announcements

Giving batteries a longer life with the Advanced Photon Source: New research uncovers a hydrogen-centered mechanism that triggers degradation in the lithium-ion batteries that power electric vehicles September 13th, 2024

NYU Abu Dhabi researchers develop novel covalent organic frameworks for precise cancer treatment delivery: NYU Abu Dhabi researchers develop novel covalent organic frameworks for precise cancer treatment delivery September 13th, 2024

New discovery aims to improve the design of microelectronic devices September 13th, 2024

New method in the fight against forever chemicals September 13th, 2024

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers/Posters

Rice research could make weird AI images a thing of the past: New diffusion model approach solves the aspect ratio problem September 13th, 2024

Breakthrough in proton barrier films using pore-free graphene oxide: Kumamoto University researchers achieve new milestone in advanced coating technologies September 13th, 2024

Quantum researchers cause controlled ‘wobble’ in the nucleus of a single atom September 13th, 2024

New nanomaterial could transform how we visualise fingerprints: Innovative nanomaterials have the potential to revolutionise forensic science, particularly in the detection of latent (non-visible) fingermarks September 13th, 2024

Research partnerships

Gene therapy relieves back pain, repairs damaged disc in mice: Study suggests nanocarriers loaded with DNA could replace opioids May 17th, 2024

Discovery points path to flash-like memory for storing qubits: Rice find could hasten development of nonvolatile quantum memory April 5th, 2024

Researchers’ approach may protect quantum computers from attacks March 8th, 2024

Development of zinc oxide nanopagoda array photoelectrode: photoelectrochemical water-splitting hydrogen production January 12th, 2024

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project