In both cases, we obtained 99% conversion of POT, 90 % conversion of IBA and 99 % of S. The Mn increased up to 40-50,000 g.mol -1 (see Table for details). Under the same degradation conditions, oligomers of DP in agreement with the amount of incorporated POT could be obtained (Figure ). With higher Mn for the pristine copolymer, the percentage of Mn reduction is higher and reached 85% and 89% for the polystyrene and PIBA respectively. This confirms that the length of the oligomers is not impacted by the chain length of the polymer but only by the amount of initial POT added in the polymerization medium.