Research on Depolymerisation and Regeneration of Epoxy Resin Cured With Anhydrides

The recovery and utilization of thermosetting resins without any pollution is always concerned in the FRP (Fiber Reinforce Plastic) industry. Based on the theory that the ester exchange reaction between alcoholic hydroxyl and ester groups will occur in existence of catalyst, a new technology was developed to recycle bisphenol-A epoxy resin cured with anhydrides. The orthogonal experiments were carried out and influence factors were analyzed in order to get a higher decomposition ratio of epoxy resin. Decomposed products were analysed with FTIR and were further applied to prepare regenerated resin by mixing with fresh epoxy resin. The degree of three-dimensional network and mechanical properties of original and regenerated resins were measured and compared. The results showed that the decomposition ratio could reach 98% while heated at 180 °C with the NaOH catalyst in ethylene glycol (EG) for 7 hours and the properties of the regenerated resin were good.