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Amphiphilic graft copolymers were prepared via a grafting through approach to yield materials with a hydrophilic backbone and hydrophobic arms. The thermally responsive macromonomers were designed to contain a Diels–Alder adduct such that cyclo‐reversion would cleave the arms from the backbone thus altering polymer topology, composition and solubility. The macromonomers were prepared via light‐inducted atom transfer radical polymerization followed by post‐polymerization modification to install a polymerizable functionality. Next, free radical polymerization was employed to yield thermally responsive amphiphilic graft copolymers, whose solution state characteristics were extensively characterized by UV/Vis spectroscopy and fluorimetry. Due to the amphiphilic nature of the graft copolymer, some unexpected results occurred because of aggregation and solubility limitations. Furthermore, it was discovered that poly(N‐isopropyl acrylamide) exhibited distinct and unique aggregation properties by itself.

Thermo‐responsive monomers were designed to contain a Diels‐Alder (DA) adduct such that cyclo‐reversion would yield either the maleimide or the furan unit attached to the polymer chain. These thermally responsive monomers were then copolymerized withN‐isopropylacrylamide (NIPAM) via reversible addition‐fragmentation chain‐transfer (RAFT) polymerization to yield linear gradient‐copolymer structures as a comparison to existing nanogel/starlike systems to understand how polymer topology and composition influence solution‐state properties. Using UV–Vis spectroscopy, it was determined that solution‐state properties were thermally dependent and influenced by a number of variables such as comonomer feed ratio, polymer chain end functionality, and polymer backbone length and composition. Manipulation of the feed ratio allowed for control over the cloud point, including the breadth and location of phase separation. Thermal treatment of these copolymers revealed tunable and predictable variations in previously observed transitions, directly correlated to cleavage of the DA adducts and change in polymer backbone composition. Finally, on cooling cycles, a double sigmoid was sometimes observed, indicating a complex globule to random coil transition correlated to polymer chain end composition. These studies help understand how to untie the “monkey's fist.”