A RADICAL-ANION MECHANISM FOR THE PHASE-TRANSFER CATALYZED DEPOLYMERIZATION OF POLY(2,6-DIMETHYL-1,4-PHENYLENE OXIDE)

This paper describes a novel mechanism for the depolymerization of poly(2,6-dimethyl-1,4-phenylene oxide). This radical-anion mechanism is responsible for liquid (organic solvent)-liquid (aqueous inorganic base) phase transfer catalyzed depolymerization of poly(2,6-dimethyl-1,4-phenylene oxide). This depolymerization occurs through the addition of an aryloxy radical to the terminal phenolate anion of the polymer. The particular example discussed in this paper refers to the depolymerization of poly(2,6-dimethyl-1,4-phenylene oxide) in the presence of either 2,4,6-trimethylphenol or 4-tert-butyl-2,6-dimethylphenol. The similarities and differences between the phase transfer catalyzed polymerization of 4-bromo-2,6-dimethylphenol in the presence of 2,4,6-trimethylphenol and 4-tert-butyl-2,6-dimethylphenol and the phase transfer catalyzed depolymerization of poly(2,6-dimethyl-1,4-phenylene oxide) in the presence of the same two phenols are discussed. © 1990 Springer-Verlag.