Cleavable Bio-Based Epoxy Matrix for More Eco-Sustainable Thermoset Composite Components

Area of Science:

• Materials Science
• Polymer Chemistry
• Sustainable Engineering

Background:

• Traditional thermoset epoxy resins pose end-of-life challenges.
• Cleavable bio-based epoxy systems offer a sustainable alternative.
• These systems enable circularity through matrix and fiber recovery.

Purpose of the Study:

• To characterize a new commercial cleavable bio-resin formulation.
• To evaluate its processability and recyclability in polymer composites.
• To investigate the impact of post-curing regimes on material properties.

Main Methods:

• Characterization of resin thermal stability and glass transition temperature (Tg).
• Fabrication of composite laminates (glass and carbon) using vacuum-assisted resin transfer molding.
• Evaluation of flexural behavior, microstructure, and dynamic-mechanical properties.
• Implementation of a chemical recycling procedure for material recovery.

Main Results:

• Non-post-cured resin exhibited the highest Tg (76.6 °C).
• Post-curing at 100 °C enhanced crosslinking, improving flexural strength by 3% (carbon) and 12% (glass).
• Post-curing at 140 °C negatively impacted mechanical performance.
• Successful recovery of thermoplastic-based resin and fibers was demonstrated.

Conclusions:

• The cleavable bio-resin formulation is suitable for fabricating fully recyclable polymer composites.
• Optimized post-curing (100 °C) enhances composite mechanical properties.
• The developed recycling process confirms the feasibility of a circular economy approach for these materials.