Linear tetrablock quaterpolymers via triple click reactions, azide-alkyne, diels-alder, and nitroxide radical coupling in a one-pot fashion

Azide-alkyne and Diels-Alder click reactions together with a click-like nitroxide radical coupling reaction were used in a one-pot fashion to generate tetrablock quaterpolymer. The various living polymerization generated linear polymers with orthogonal end-functionalities, maleimide-terminated poly(ethylene glycol) (PEG-MI), anthracene- and azide-terminated polystyrene, alkyne- and bromide-terminated poly(tert-butyl acrylate) or alkyne-poly(n-butyl acrylate), and tetramethylpiperidine-1-oxyl (TEMPO)-terminated poly(Îμ- caprolactone) (PCL-TEMPO) were clicked together in a one-pot fashion to generate PEG-b-PS-b-PtBA-b-PCL or PEG-b-PS-b-PnBA-b-PCL quaterpolymer using Cu(0), CuBr, and N,N,Nâ€2,Nâ€3,Nâ€3- pentamethyldiethylenetriamine as catalyst in dimethyl formamide at 80 °C for 36 h. Linear precursors and target quaterpolymers were analyzed via ¹H NMR and gel permeation chromatography.