Synthesis and cryogenic performance of closed-loop recycled Al2O3/epoxy resins composites

Abstract

The non-degradability of epoxy present environmental and economic challenges. This study synthesized a degradable epoxy resin with ester bonds using a novel method. The synthesized resin was mixed with KH560-modified micro-sized spherical α-Al2O3 particles at different concentrations to produce the A-TPHE. The cured A-TPHE exhibited excellent mechanical properties, including high tensile and shear strength (∼100 MPa), as well as outstanding impact resistance. Furthermore, DMA, DSC, and TGA analyses revealed that the composites had a high glass transition temperature (>100 °C) and good thermal stability. Notably, the A-TPHE80 % filler achieved a favorable thermal conductivity of 1.2 W/mK at 77 K. A-TPHE also demonstrated good insulation properties. The degradation of the resins was assessed at 30 wt% NaOH, and the recovered filtrate facilitated closed-loop recycling of the composite material with a consistent recovery rate exceeding 70 %. In conclusion, this study establishes a foundation for the application of degradable thermosetting materials in cryogenic environments.