Poly(difluorophosphazene): A New Intermediate for the Synthesis of Poly(organophosphazenes)

Although many poly(organophosphazenes) have been synthesized, new preparative pathways are needed, especially for polymers that contain alkyl side groups. A new development involves the use of poly(difluorophosphazene), (NPC1₂) instead of poly-(dichlorophosphazene), (NPC1²)_n, as a substrate for reactions with organometallic reagents. This approach has allowed the preparation of a new class of poly(organophosphazenes) that possess substituent groups linked to the skeleton through direct phosphorus-carbon bonds. The synthesis of uncrosslinked poly-(difluorophosphazene) and its reactions with alkoxides and amines are also reviewed.