Vitrimer ionogels towards sustainable solid-state electrolytes.

Area of Science:

• Materials Science
• Polymer Chemistry
• Electrochemistry

Background:

• Flexible, stretchable, and wearable devices require advanced polymer electrolytes like ionogels.
• Improving ionogel longevity is crucial due to repeated deformation and susceptibility to damage during use.
• Vitrimer chemistry offers a promising route to enhance material lifespan through self-healing capabilities.

Purpose of the Study:

• To prepare novel polythioether vitrimer networks utilizing an S-transalkylation exchange reaction.
• To fabricate dynamic polythioether ionogels by incorporating ionic liquids.
• To investigate the vitrimer properties, ionic conductivity, and dynamic behavior of the developed ionogels.

Main Methods:

• Synthesis of polythioether vitrimer networks via thiol-ene Michael addition and S-transalkylation.
• Incorporation of ionic liquids (1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide or EMIM triflate) into the polymer network.
• Characterization of mechanical properties (Young's modulus) and ionic conductivity at room temperature.

Main Results:

• The polythioether networks exhibited vitrimer characteristics, including self-healing and stress relaxation, due to the S-transalkylation exchange reaction.
• The fabricated ionogels showed a Young's modulus of 0.9 MPa and ionic conductivities around 10^-4 S cm^-1.
• Ionic liquid addition influenced dynamic properties, potentially through dilution and screening effects, leading to less efficient healing but improved dimensional stability.

Conclusions:

• This work presents the first vitrimer ionogels based on an S-transalkylation exchange reaction.
• The developed ionogels offer a pathway for creating longer-lasting, tunable dynamic materials for flexible electronics.
• While ionic liquid addition impacts healing efficiency, it enhances dimensional stability, crucial for specific application temperatures.