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In this study polyrotaxane (PR)-based triblock copolymers were first synthesized via the atom transfer radical polymerization (ATRP) of N-isopropylacrylamide initiated with the self-assembly of a distal 2-bromoisobutyryl end-capped Pluronic 17R4 with a varying amount of α-cyclodextrins (α-CDs) in the presence of CuCl/PMDETA at 25°C in aqueous solution. the α-CDs entrapped on the copolymer chain were then linked with hexamethylene diisocyanate to give rise to novel slightly cross-linked polyrotaxanes (SCPRs) in DMF at 45°C. the structures of the PR-based triblock copolymers and SCPRs were characterized by ¹H NMR, ¹³C CP/MAS, GPC and TGA analyses. the number-average molecular weight of the resulting SCPRs was nearly three and five times of their precursor after linking with a low polydispersity index range of 1.08-1.28. the thermo-responsive transition of both PR-based supramolecular polymers in aqueous solution was demonstrated by turbidity measurements and the self-aggregated morphologies were also evidenced by TEM observations.