Ring-opening bulk polymerization of five- and six-membered cyclic phosphonates using maghnite, a nontoxic proton exchanged montmorillonite clay

Abstract

A new method of preparation of poly(alkylene H-phosphonate)s by ring-opening bulk polymerization of the five- and six-membered cyclic phosphonates monomers using the nontoxic Maghnite-H+ as the initiator is described. Cyclic phosphonate monomers have been first synthesized. In particular, a new one-step synthesis of 2-hydro-2-oxo-1,3,2-dioxaphospholane is reported with a yield of 70%. The efficiency of the montmorillonite sheet silicate clay which exchanged with protons, called Maghnite-H+, as cationic initiator has been proved and the resulting biomimetic poly(alkylene H-phosphonate)s have been characterized. The Maghnite-H+ regenerated after one turn-over has showed to be still efficient as initiator for the ring-opening polymerization. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011