Nonionic double thermoresponsive diblock copolymers with both upper critical solution temperature (UCST) and lower critical solution temperature (LCST) phase transitions are synthesized via eco‐friendly photoiniferter reversible addition–fragmentation chain transfer polymerization. While the biocompatible random copolymer of di(ethylene glycol) methyl ether methacrylate and oligo(ethylene glycol) methacrylate accounts for the LCST transition, the block of polymethacrylamide from an easily accessible monomer with low health hazard is responsible for the UCST transition. Temperature‐dependent dynamic light scattering measurements confirm the formation of micellar aggregates in water at the temperatures below UCST‐ and above LCST‐type cloud points. Additionally, the temperature interval between UCST and LCST, where both blocks are dissolved, can be tailored by varying the comonomer ratio in the random copolymer block. With these unique advantages, the presented work introduces a new polymer system for the design of schizophrenic polymers.

The tailored synthesis of graft copolymers from acrylic and methacrylic monomers can be accomplished solely through photoiniferter reversible addition−fragmentation chain transfer (RAFT) polymerization. Samples with poly[oligo(ethylene glycol) methacrylate] (POEGMA) backbones...

Incorporating multiple pyridyl disulfide (PDS) moieties into polymer chains allows the fabrication of a chemically cross‐linked hydrogel through the rapid thiol–disulfide exchange reaction. By aminolysis in the presence of 2,2′‐dithiodipyridine (DTP), the end groups of polymers synthesized via reversible addition−fragmentation chain transfer (RAFT) polymerization can readily be converted into PDS‐groups. In this contribution, a RAFT‐synthesized graft copolymer with thermoresponsive poly[di(ethylene glycol) methyl ether methacrylate] forming the backbone and hydrophilic poly(N,N‐dimethylacrylamide) as the side chains is presented. The copolymer chains exhibit surprisingly a two‐step lower critical solution temperature transition in aqueous solutions. After modification of the end groups of the backbone and side chains, the PDS‐terminated chains can react with a dithiol cross‐linker to form a thermoresponsive hydrogel. In a reducing environment, the cleavable disulfide linkages lead to on‐demand dissolution of the hydrogel. The resulting thiol‐terminated chains undergo a reversible sol–gel transition in response to redox variations, expanding the potential application areas of such a polymer system.