Control of End Groups in Anionic Polymerizations Using Phosphazene Bases and Protic Precursors As Initiating System (XH-Bu^tP₄ Approach): Application to the Ring-Opening Polymerization of Cyclopropane-1,1-Dicarboxylates

Nicolas Illy (1) , Sylvie Boileau (1) , William Buchmann (2) , Jacques Penelle (1) , Valessa Barbier (1)

1 ICMPE - Institut de Chimie et des Matériaux Paris-Est
2 LAMBE - Laboratoire Analyse et Modélisation pour la Biologie et l'Environnement

A synthetic method involving the in situ generation of an anionic initiator X⁻ obtained by reaction of its conjugate acid precursor XH with Bu^tP₄ phosphazene base was tested as a possible way to easily and better control the end groups of polymers derived from the anionic ring-opening polymerization of cyclopropane-1,1-dicarboxylates. Several types of precursors were investigated, including thiols, alcohols, a carbazole, and a malonate. In all but one cases, a living polymerization mechanism could be observed, which was exploited to control the nature of the terminal end groups by reaction of the propagating malonate carbanion R−C(COOPr)₂⁻ with alkylating agents. It was also demonstrated that toluene was a much better solvent than the traditional one used in these reactions (THF) as a larger range of available temperatures was available despite an almost identical solvent influence on the polymerization. Exploitation of this feature provided access to higher degrees of polymerization than previously possible.

Domaines: Polymères; Matériaux; Chimie organique

Nicolas Illy, Sylvie Boileau, William Buchmann, Jacques Penelle, Valessa Barbier. Control of End Groups in Anionic Polymerizations Using Phosphazene Bases and Protic Precursors As Initiating System (XH-Bu^tP₄ Approach): Application to the Ring-Opening Polymerization of Cyclopropane-1,1-Dicarboxylates. Macromolecules, 2010, 43 (21), pp.8782-8789. ⟨10.1021/ma1016506⟩. ⟨hal-02090356⟩