π-π Conjugated Bonds Stacking/Scattering for Switchable Lubrication in Supramolecular Hydrogel

Area of Science:

• Materials Science
• Polymer Chemistry
• Tribology

Background:

• Conventional polymer materials lack dynamic lubrication adjustment capabilities.
• This limitation hinders applications in intelligent motion devices and soft robotics.
• There is a need for adaptable lubrication technologies responding to external stimuli.

Purpose of the Study:

• To develop a dual-responsive lubricating hydrogel with tunable friction properties.
• To investigate the hydrogel's response to thermal and shear stimuli.
• To explore its potential as an intelligent lubrication material.

Main Methods:

• Fabrication of a hydrogel with a dual-responsive supramolecular network.
• Integration of the network into a stable polymer framework.
• Evaluation of the hydrogel's lubrication performance under varying thermal and shear conditions.

Main Results:

• The hydrogel exhibits a reversible gel-sol transition under thermal or shear stress.
• This transition triggers the secretion of a lubricating supramolecular layer.
• A significant reduction in the coefficient of friction (COF), up to 20-fold, was observed.
• The material mimics the self-lubricating properties of hagfish mucus.

Conclusions:

• The developed hydrogel functions as an intelligent lubrication material.
• It offers dynamic friction adjustment in response to external stimuli.
• This technology holds promise for advanced adaptive lubrication systems.