Reduction of cracked residue from waste epoxy resin by addition of thermoplastic resin

Abstract

Reduction of cracked residue of thermosetting resin (TSR) was studied to improve oil recovery from waste plastics that include TSR. In the process of thermal decomposition, resin turns to residue through crosslinking and cyclization by radical recombination. Inhibition of radical recombination was investigated by means of addition of thermoplastic resin (TPR) as a radical acceptor to TSR during pyrolysis. Epoxy resin (EP; TSR) was pyrolyzed at 500°C for 1 hour and 23 wt% of EP turned into residue. By addition of polyethylene (PE; TPR) to EP (PE:EP=4:1, weight base), residue of EP was reduced to 5 wt%. On the other hand, decomposition of residuewas not observed when residue of EP was pyrolyzed with PE. From TG-MS study of cracked gas from EP and/or PE, it was indicated that reduction of residue was caused by intermolecular reaction between EP and PE.