Anionic polymerization of oxirane in the presence of the polyiminophosphazene base t‐Bu‐P4

Abstract The use of the polyiminophosphazene base t ‐Bu‐P 4 (1) for the anionic polymerization of ethylene oxide is described. Polymerization initiated by a monoalkoxide of the protonated base leads to well‐defined poly(ethylene oxide)s with low polydispersity ( M w / M n ≈ 1.1). Furthermore, graft copolymers of poly[ethylene‐ co ‐(vinyl alcohol)] (PEVA) with poly(ethylene oxide) and a star macromolecule were synthesized from multifunctional polyalkoxides in high yields.