Polymeric materials based on main group elements: the recent development of ambient temperature and controlled routes to polyphosphazenes

Abstract

This Perspective discusses the development of new routes to polyphosphazenes, [R₂PN]_n, that occur at ambient temperature and, in some cases, allow molecular weight control and access to narrow molecular weight distributions and block copolymers. For example, the room temperature silyl-carborane initiated ring-opening polymerisation of (NPCl₂)₃ is described together with chain growth condensation polymerisations of phosphoranimines Cl₃PNSiMe₃ and BrMePhPNSiMe₃. Recent works on donor-stabilised cationic phosphoranimines are also discussed.