This article reports the development of a new catalytic process that takes advantage of the exchange reaction between aluminium alkoxides and alcohols to obtain functionalized low molecular weight oligomers by anionic ring-opening polymerization. The aluminium alkoxides can be used in homogeneous medium or grafted on a porous support to make possible a heterogeneous process. omega-Hydroxy oligo polycaprolactones macromonomers with 2-hydroxyethylmethacrylate or hydroxymethylstyrene as polymerizable end groups have been synthesized and characterized by NMR and SEC. Mass spectrometry (LSIMS) has been used in an attempt to determine the MWD. These macromonomers have been engaged in copolymerization with styrene and the reactivity ratios have been approached.