“…Therefore, we turned our attention to light‐mediated polymerization techniques, as recent works have demonstrated that they are versatile tools to mediate controlled polymerization following radical, [34–42] cationic, [43–47] and metathesis pathways [48–50] at ambient temperature (Figure 1B) [51] . In particular, we envisioned that the photoinduced electron/energy transfer‐reversible addition/fragmentation chain transfer (PET‐RAFT) polymerization developed by Boyer and co‐workers [52–56] could be employed to mediate the radical ring‐opening cascade copolymerization (rROCCP) [57, 58] of the macrocyclic allylic sulfone with acrylates or acrylamides (Figure 1C). Unlike the polymerization that is thermally initiated by azobisisobutyronitrile (AIBN), which requires high temperatures (80–100 °C) to maintain a sufficiently high rate of propagation, PET‐RAFT can be performed at mild temperatures, thereby enabling favorable comonomer reactivity ratios in copolymerization [59] .…”