New type polyrotaxanes based on polyethyleneimine and α-cyclodextrin

Functional polyrotaxanes of N-alkanoylpolyethyleneimine@ α-cyclodextrin type are synthesized by acylation of the polypseudorotaxane precursor, namely, a polyethylenimine@ α-cyclodextrin inclusion complex, with excess of carboxylic acid anhydrides. In the course of the processing, α-cyclo-dextrin moieties are also fully O-acylated. The introduction of acyl moieties into polyethyleneimine backbone prevents the expulsion of α-cyclodextrin rings from this backbone.