Maghnite-H + (Mag-H), proton-exchanged Montmorillonite, catalyzed the cationic copolymerization of 2-Chloroethyl Vinyl Ether (CEVE) with Styrene (St) in a solvent free system. The objective is to synthesize an end-group functionalized copolymer. The advantage of the Mag-H lies in its capacity to solve ecological (green catalyst) and economic problems, and also to the fact that the reactions are carried out under moderate conditions, solvent free and at room temperature. A kinetic study was carried out, and the products obtained were characterized using different methods of analysis, including IR, 1 H and 13 C NMR and viscosimetry.