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Amine-functional poly(ethylene glycol)(PEG) copolymers have beenprepared that exhibit thermo- and pH- responsive behavior in aqueoussolution. Three novel tertiary di(n-alkyl)glycidylaminemonomers have been introduced for anionic ring-opening copolymerization(AROcP) with ethylene oxide (EO): N,N-di(n-butyl)glycidylamine (DButGA), N,N-di(n-hexyl)glycidylamine (DHexGA),and N,N-di(n-octyl)glycidylamine(DOctGA). Via controlled AROcP we synthesized well-defined (Mw/Mn= 1.05–1.14),water-soluble block- and gradient-type PEG copolymers, containingup to 25 mol % of the respective dialkylglycidylamine comonomer. Molecularweights ranged from 4900 to 12 000 g mol–1. Detailed in-situ 1H NMR kinetics and 13Ctriad analyses elucidate the microstructures of the copolymers andthe relative reactivity of the novel comonomers. Notably, the n-alkyl chain length had no significant influence on therelative reactivity of the glycidylamine comonomers. Calculated reactivityratios ranged from rEO= 1.84, rDButGA= 0.49 to rEO= 1.78, rDOctGA= 0.42, manifestingthe formation of gradient copolymers. Thermo- and pH-responsive propertiesof these copolymers are precisely tunable by the comonomer ratio,and cloud points in aqueous solution can be adjusted between 21 and93 °C. Electron paramagnetic resonance (EPR) spectroscopic studieswith TEMPO as a spin probe were conducted to elucidate host–guestinteractions of the copolymers. Unexpectedly, the n-alkyl chain length of the different glycidylamine comonomers onlyinfluences the inverse phase transition of the gradient copolymers,but not of the block copolymers on the nanoscale. Self-assembly ofthe block- and gradient-type copolymers in aqueous alkaline solutionby both static and dynamic light scattering has also been investigatedafter confirming the existence of pure unimers in methanol. [ABSTRACT FROM AUTHOR]