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To highlight whether γ‐cyclodextrins (CDs) facilitate propargylamine monosubstituted β‐CDs (PA‐β‐CDs) as end stoppers to get threaded onto a distal azide terminated poly(2‐hydroxyethylmethacrylate) (PHEMA) homopolymer (PH‐46‐2N3) to create linear and hyperbranched polyrotaxanes (PRs) via the in situ copper‐catalyzed azide/alkyne cycloaddition (CuAAC), PH‐46‐2N3 is self‐assembled with a varying amount of γ‐CDs in water and then subjected the CuAAC with PA‐β‐CDs to end‐cap the resulting γ‐CD‐PHEMA polypseudorotaxanes (PPRs) into the γ‐CD‐PHEMA PRs. It demonstrates that γ‐CDs cannot promote PA‐β‐CDs to be entrapped on the PHEMA chain most likely due to their different cavity size and molecular framework and linear PRs are always formed with up to 29% γ‐CD coverage ratio along the PHEMA axis thereof. [ABSTRACT FROM AUTHOR]

A kind of γ-(cyclodextrin) (γ-CD)-based polyrotaxane (PR) is synthesized via an aqueous click reaction between propargylamine-substituted β-CD and polypseudorotaxanes (PPRs) self-assembled from azido-endcapped PNIPAAm- b-Pluronic F68- b-PNIPAAm with a varying amount of γ-CD. The evolution of the self assembly, dependent on the preparation process, is observable by X-ray diffraction (XRD) and DSC analyses. The γ-CD is able to be included and preferably entrapped on the PNIPAAm blocks, showing a unique loose-fit aggregate structure after the click reaction. Most γ-CDs gradually slip over to the middle PPG block of Pluronic F68, giving rise to a characteristic channel-type crystal structure in the dialy­sis process. In addition, the lower critical solution temperature (LCST) is sharply enhanced due to the coverage of the remaining γ-CDs hindering the thermally responsive aggregation of the PNIPAAm blocks. [ABSTRACT FROM AUTHOR]

When γ-CDs are added to an aqueous solution of PNIPAAm- b-PEG- b-PNIPAAm block copolymer, they are threaded onto the polymer chains to give loose-fit polypseudorotaxanes (PPRs). The inclusion complexation shows a marked dependence on the length of the PNIPAAm blocks although the threaded γ-CDs are preferably located on the central PEG block. The structure of the resulting PPRs is characterized by using XRD, 1H and 13C CP/MAS NMR, TGA FTIR, and DSC analyses. Because of the mismatched fit between the guest polymer chain and the cavity of the host γ-CDs, these PPRs may be promising in applications as solid stimuli-responsive materials. [ABSTRACT FROM AUTHOR]