Ring-Ring and Ring-Chain Equilibration of Dimethylphosphazenes. Relation to Phosphazene Polymerization

H. R. Allcock, D. B. Patterson

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Hexamethylcyclotriphosphazene, [NP(CH3)2]3, and octamethylcyclotetraphosphazene, [NP(CH3)2]4, participate in a ring-ring equilibration between 200 and 350 °C, but they do not polymerize. A ΔH value of 10.2 kcal and a ΔS value of 14.3 eu were determined for the tetramer-trimer interconversion. The equilibration is inhibited by base. Acids accelerate equilibration and also yield linear low molecular weight compounds: these species cyclize to III and IV when heated. The results are compared with the ring-high polymer and ring-ring interconversions in the halogenophosphazene, dimethylsiloxane, dimethylsilthiane, and polysulfur series.

Original languageEnglish (US)
Pages (from-to)197-200
Number of pages4
JournalInorganic chemistry
Issue number1
StatePublished - Jan 1 1977


All Science Journal Classification (ASJC) codes

  • Physical and Theoretical Chemistry
  • Inorganic Chemistry

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