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Photocleavable Regenerative Network Materials with Exceptional and Repeatable Viscoelastic Manipulability.
Minami Oka1, Hideaki Takagi2, Tomotaka Miyazawa3
1Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro, Tokyo, 153-8902, Japan.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|August 2, 2021
Summary
Researchers developed a novel photocleavable regenerative network (PRN) using photoresponsive hexaarylbiimidazoles. This solventless material offers tunable viscoelasticity and enables applications in sustainable adhesives and 3D printing.
Area of Science:
- Materials Science
- Polymer Chemistry
- Sustainable Technology
Background:
- Solventless systems for network materials are crucial for sustainable technology.
- Designing photoresponsive materials with repeatable property changes remains challenging.
- Photostimulation offers precise spatial and temporal control.
Purpose of the Study:
- To develop a photocleavable regenerative network (PRN) for advanced material applications.
- To synthesize photoresponsive network materials using poly(dimethylsiloxane)s and hexaarylbiimidazoles.
- To demonstrate the material's potential as a photo-melt adhesive and photo-scissible string.
Main Methods:
- Synthesis of star-shaped poly(dimethylsiloxane)s with triphenylimidazole end groups.
- Utilized urea anion catalysis for controlled ring-opening polymerization (ROP) of cyclic siloxane.
- Performed rheological measurements to analyze changes in storage and loss moduli upon photoirradiation.
Main Results:
- Successfully synthesized photocleavable regenerative networks (PRNs).
- Demonstrated drastic, reversible changes in viscoelastic properties (storage and loss moduli) upon photoirradiation in the solid state.
- Exhibited retained solidity despite photocontrolled viscoelasticity changes.
Conclusions:
- The developed PRNs offer a solventless, photo-controllable method for modulating material properties.
- PRNs show promise as next-generation sustainable adhesives, sealants, and 3D printing materials.
- The material's properties allow for spatially and temporally local manipulation and excellent reversibility.
