Alkoxyamines derived from beta-phosphorylated nitroxides, and use thereof for preparing polymerized or non-polymerized mono- or polyalkoxyamines

An alkoxyamine of formula (I):

• in which A is selected from a hydroxyl radical;
• a radical MeO— in which Me represents an alkali metal;
• a H4N+— radical, a Bu4N+— radical;
• a Bu3HN+— radical;
• or a chlorine atom;
• R represents a hydrogen atom or a methyl radical;
• M is a free-radical-polymerizable vinyl monomer sequence;
• n is an integer that may be equal to 0, with the proviso that when A is selected from OH or CH3 and R is H, n is not 0,.