Dual Sacrificial Strategy Toward Tough and Recyclable CO₂-Sourced Epoxy Thermosets

Area of Science:

• Polymer Chemistry
• Materials Science
• Sustainable Chemistry

Background:

• Thermosetting epoxy resins face challenges in balancing high performance (strength and toughness) with chemical recyclability.
• Sustainable polymer advancement requires innovative solutions to overcome this performance-degradability trade-off.

Purpose of the Study:

• To develop high-performance, chemically recyclable thermosetting epoxy resins.
• To introduce a dual sacrificial strategy using CO2-derived poly(ether-carbonate) polyols as epoxy hardeners.

Main Methods:

• Employing CO2-derived poly(ether-carbonate) polyols with flexible ether and cleavable carbonate segments as epoxy hardeners.
• Investigating dual-stage crosslinking mechanisms via model reactions and curing kinetics.
• Characterizing thermomechanical properties, toughness, and chemical recyclability.

Main Results:

• The dual sacrificial design significantly enhances mechanical properties and enables degradability.
• Achieved tunable thermomechanical properties (Tg = 53-129 °C) and >300% increased toughness (up to 5.2 MJ m-3).
• Demonstrated rapid catalytic chemical recyclability (<4 h at 60 °C) with reusable degradation products.

Conclusions:

• The developed epoxy thermosets reconcile mechanical robustness with chemical recyclability.
• This methodology offers a viable pathway toward sustainable epoxy production.
• Validated performance in practical applications like composites and electronic packaging.