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A Strong Adhesive with High Switching Ratio Achieved by Phototriggered Azobenzene-Terminated Hyperbranched Polymer
Chenghao Zhang1, Yichen Ding1, Tang Li1
1Department of Polymer Science and Engineering, State Key Laboratory of Coordination Chemistry, Key Laboratory of High Performance Polymer Material and Technology, MOE, School of Chemistry, Nanjing University, Nanjing, Jiangsu 210023, China.
ACS Applied Materials & Interfaces
|June 26, 2026
Summary
Researchers developed a novel hyperbranched polymer adhesive using azobenzene groups. This photoswitchable adhesive achieves high adhesion strength and excellent switchability, overcoming previous limitations in reversible adhesive technology.
Area of Science:
- Materials Science
- Polymer Chemistry
- Surface Science
Background:
- Photoswitchable adhesives utilizing azobenzene groups are crucial for applications in flexible electronics, micro/nanotransfer printing, and soft robotics.
- A key challenge in developing these adhesives is the trade-off between adhesion strength and switchability.
- Existing phototriggered reversible adhesives often compromise one property for the other.
Purpose of the Study:
- To design and synthesize a novel hyperbranched polymer with terminal azobenzene groups for use as a photoswitchable adhesive.
- To overcome the inherent contradiction between high adhesion strength and efficient switchability in reversible adhesives.
- To demonstrate the potential of this new material for advanced manufacturing applications.
Main Methods:
- Synthesis of a hyperbranched polymer incorporating abundant hydrogen bonds through monomer selection.
- Functionalization of the polymer with terminal azobenzene groups to enable photoswitching.
- Evaluation of adhesion strength and switching ratio under UV irradiation on a glass substrate.
Main Results:
- The developed hyperbranched polymer adhesive exhibited both high adhesion strength (8.07 MPa) and a high switching ratio (53.80).
- Introduction of hydrogen bonds enhanced the polymer's cohesive strength and interfacial interactions, boosting adhesion.
- UV irradiation induced a significant solid-liquid phase transition due to azobenzene groups, leading to strong switchability.
Conclusions:
- The novel hyperbranched polymer adhesive successfully balances high adhesion strength and excellent switchability.
- This material offers a promising alternative for developing advanced switchable adhesives for manufacturing.
- The findings pave the way for new phototriggered reversible adhesive technologies.
Keywords:
azobenzenehyperbranched polymerphotoswitchingphototriggered phase transitionreversible adhesiveMore Related Videos
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