Recovery and Reutilization of Epoxy Thermoset via Acidic Ion Exchange Resin-Induced Controllable Oxidative Degradation and Subsequent Microspheroidization

The high mechanical strength and thermal resistance of an epoxy (EP) thermoset make it ideal for wide applications in industries such as energy, aerospace, electronics, and construction but increase the difficulty in controllable and efficient recovery. Herein, acidic ion exchange resin-induced oxidative degradation of the EP thermoset was developed to obtain homogeneous oligomers at 85 °C in 4 h. The C–N bond is activated by free H+ of the ion exchange resin while the oxidation depth was dependent of acid groups of the ion exchange resin. There was no significant difference in the molecular weight or polydispersity index after complete degradation even when varying the degradation temperature and time. Even more, homogeneous degraded EP microspheres can be easily obtained by a water-induced phase separation method and it was a good candidate for wastewater treatment in the field of dye removal with a CV adsorption capacity of 270 mg/g and oil–water separation with a water flux of 57,325 L m–2 h–1 and a separation efficiency of 99.9%. This work overcomes the shortcomings of non-controllable degradation and the resultant complex products in traditional oxidative degradation systems of the EP thermoset. In addition, it provides a new insight into controllable recovery and value-added reutilization by taking advantages of both the waste EP and waste acidic ion exchange resins.