Vacuum pyrolysis of polymeric wastes containing hazardous cyano groups

Abstract

Vacuum pyrolysis of polymeric wastes containing hazardous cyano groups was studied using low temperature pyrolysis mass spectrometry. Specifically, the study analyzed the presence of toxic compounds among the pyrolysis products. The polymers were pyrolyzed directly in the solid probe of a quadruple mass spectrometer within an ion source at a pressure of 10−6 Torr and then sorted by quadrupole mass analyzer. Polyethyl cyanoacrylate degrades by depolymerization, mostly into the ethyl cyanoacrylate monomer units. The degradation of polyurethane produces nonpolymeric urethane, isocyanates, amines and ethers. Polyacrylonitrile degrades via a depolymerization pathway into oligonitriles, acrylonitrile, ammonia and hydrogen cyanide.