Rational design of thermoresponsive polymers allows facile control over LCST/UCST and nano-object shapes. Despite tremendous progress, it remains a challenge to monitor chain conformations as the solvent isotope affects types of phase transitions. This study aims at addressing the challenge by construction of thermoresponsive Y-junction-bearing polyacrylamides with nontraditional intrinsic luminescence. With an increasing carbon number of substituents connecting with ester groups (x = 1, 2, 3, 4, 6, 8, 10, and 12), copolymers transform from hydrophilic (x = 1) to LCST (x = 2) and dual LCST/UCST (x ≥ 3) in H 2 O, while no UCST is available in D 2 O due to more stable amide−solvent hydrogen bonding and strengthened intra-/ intermolecular interactions. Meanwhile, copolymer aqueous solutions can exhibit substituent/pH-dependent evolution orders of single, dual, and triple phase transitions, and asymmetric Vshaped evolution of LCST/UCST values with increasing pH is usually observed. Although 1 H NMR analysis can only reveal the solvation status of subunits in the LCST region, fluorescence analysis allows to elucidate intra-/intermolecular hydrogen bonding interactions in LCST/UCST regions. Thermoinduced self-assembly in water renders sphere-to-nanocapsule-to-lamella-tonanocapsule transitions. These important findings provide us with considerable insight into hydrogen bonding-related UCST formation by rational macromolecular design. Our study may open new avenues for regulating phase transitions and exploring solvent isotope effects.

Two pairs of linear and cyclic polyacrylamide-type thermoresponsive heterofunctional-dendron-bearing polymers (THDPs) are designed to achieve on-demand phase transitions and nanostructures.

A heterofunctional hexablock copolymer comprising alternating reactive and non-reactive blocks is designed to generate cyclic, dumbbell-shaped and jellyfish-like copolymers.

Rational design of ABC linear terpolymer and (c-AB)C tadpole-shaped terpolymer allows the construction of a topology-directed crystallization/thermo/pH-tunable hierarchical self-assembly platform.