13C-NMR Evidence for Hydrogen Supply by Water for Polymer Cracking in Supercritical Water

A rubber polymer (EPDM, ethylene-propylene-diene-terpolymer) vulcanized was cracked to paraffinic oil (PO) in NaOH-containing supercritical water (SCW) at 420 °C and 30 MPa. The SCW polymer cracking in not oxidative but reductive. The 13C-NMR analysis of PO obtained by SCW D2O cracking demonstrates that the terminal methyl carbons are deuterated as a clear indication of hydrogen supply by SCW in the cracking.