Phenylene sulfide polymers. II. Structure of polymers obtained by the Macallum polymerization

Polymers prepared by the Macallum homopolymerization and copolymerization were compared to a linear phenylene sulfide polymer prepared by the self‐condensation of sodium p‐chlorothiophenoxide. The properties compared included solubility, softening point, melting point, x‐ray diffraction pattern, infrared spectrum, and thermal stability. For the last named, both differential thermal analyses and thermal gravimetric analyses were obtained. The linear polyphenylene sulfide and the Macallum polymers were found to be essentially identical in all of these properties, even though the sulfur contents ofthe latter were generally higher by 15–20% of the amount present than in the linear polymer. Consideration of this identity and of the probable mechanism of the Macallum polymerization led to the postulation of a structure for the Macallum polymers consisting of a crosslinked core to which are attached more or less extended, linear chains.