Self-reporting and Biodegradable Thermosetting Solid Polymer Electrolyte

Area of Science:

• Materials Science
• Polymer Chemistry
• Electrochemistry

Background:

• Solid polymer electrolytes (SPEs) are crucial for energy storage but often lack monitoring capabilities and degradability.
• Existing thermosetting SPEs face limitations in direct physical and chemical change observation and environmental persistence.

Purpose of the Study:

• To engineer self-reporting and biodegradable thermosetting SPEs using hyperbranched poly(β-amino ester)s (HPAE-SPEs).
• To overcome limitations predicted by Flory theory in developing advanced SPE materials.
• To enable direct monitoring of physical and chemical changes in SPEs.

Main Methods:

• Synthesis of HPAE via an "A2+B4" Michael addition strategy.
• In situ crosslinking of HPAE to form HPAE-SPEs.
• Characterization of luminescence, degradation, and electrochemical performance.

Main Results:

• HPAE-SPEs exhibit multicolour luminescence for damage monitoring due to tertiary aliphatic amines.
• The SPEs are rapidly hydrolysed into non-hazardous β-amino acids and polyols via self-catalysis.
• Optimized HPAE-SPE shows ionic conductivity of 1.3×10⁻⁴ S/cm at 60°C, a Na⁺ transference number of 0.67, stable sodium plating-stripping, and low overpotential (≈190 mV).

Conclusions:

• A new paradigm for developing SPEs through multifunctional polymer engineering is established.
• The self-reporting and biodegradable properties of HPAE-SPEs significantly expand their application scope.
• This work addresses key challenges in SPE development, including monitoring and sustainability.