A testing copolymerization using only MMA and 10 mol% of PhMal was initially performed and confirmed the random introduction of PhMal into the polymer chains (see Figure in Supporting Information). We then conducted the terpolymerization at 80°C in 50 mol% of anisole, using a feed ratio [MMA]0:[PhMal]0:[DOT]0 = 90:5:5. As for MMA/DOT copolymerization and MMA/DOT/MA terpolymerization, we followed the synthesis (Figure ) and the degradation (Figure ) by (multi-detection) SEC. The strong basic degradation conditions used for the previous polymerizations can however not be used here, as they lead to the ring-opening of the maleimide unit (Figure ). It is thus impossible to discriminate between PhMal degradation and DOT-induced degradation under the strong basic conditions. Instead, milder conditions realized by ammonia (NH3) addition in methanol, knowing to degrade thioester linkages but not modifying the maleimide group (Figure ), have been applied. Notably, Figure shows a relatively strong MMD shift with a decrease of Mn from 36,300 g•mol -1 to 12,400 g•mol -1 .