Inorganic polymeric materials such as polysiloxanes are widely used. These compounds have a Si–O main chain. Polymers with a P–O main chain could also have useful properties, but have rarely been studied.

Ian Manners, University of Bristol, UK, and University of Victoria, Canada, and colleagues have synthesized a new class of inorganic polymers with a P(V)–O chain and aryl substituents (pictured, R = Ph, 4-^tBu-C₆H₄, Mes, 4-^tBu-2,6-Me₂-C₆H₂). The polymers were prepared by a thermal ring-opening polymerization, using cyclic monomers of the type (RPO₂)₃. These monomers, in turn, were synthesized via a dehydrochlorination of RPOCl₂ and RPO(OH)₂.

The properties of the resulting polymers, such as solubility and stability, strongly depend on the aryl substituent. Materials with smaller substituents are converted back to the monomers in dilute solutions, which could be useful for recycling. The polymers have a high thermal stability and can be processed into thin films.

• Ring-Opening Polymerization of Cyclic Phosphonates: Access to Inorganic Polymers with a P^V–O Main Chain,
  Marius I. Arz, Vincent T. Annibale, Nicole L. Kelly, John V. Hanna, Ian Manners,
  J. Am. Chem. Soc. 2019.
  https://doi.org/10.1021/jacs.8b13435