Characterization of the Stability and Reuse Potential of Aged Epoxy Materials for Sustainable Management of Insulation Waste

This study examines the feasibility of mechanical recycling of epoxy resins exhibiting different levels of degradation (new, thermally aged, and UV‐exposed) and their subsequent incorporation into a virgin cold‐curing epoxy matrix based on bisphenol A. Simulated aging was induced through controlled exposure to UV radiation and thermal exposure for a duration of 500 h. The recycled material, processed by an optimized cryogenic milling method into a fine powder (≈13 μm) and was dispersed as an inertial filler (1 wt.%) in the same epoxy base. Electrical characterization of the resulting composites demonstrated that volume resistivity values occur within one order of magnitude (10 14 –10 15 Ω·m) across all material compositions, while polarization indexes consistently exceeded the minimum recommended limits (≥2), indicating preserved insulating properties. Dielectric losses and relative permittivity show shift in the relaxation peak associated with the glass transition temperature, which was effectively mitigated through an additional postcuring process. Regarding tensile tests, a pronounced decline in properties was observed only in the unmodified resin following thermal aging, whereas the composites containing recycled filler maintained comparable performance levels in ultimate tensile strength (>30 MPa) and maximal elongation (>3%). The study also provides insight into the possible real‐world application of the findings in the field of sustainable energy.