A novel supramolecular graft copolymer via cucurbit[8]uril-based complexation and its self-assembly

A novel supramolecular graft copolymer (SGP) composed of viologen-containing copolymer (P(DMA-co-diEV)) as the main chain and Np ended PNIPAM (Np-PNIPAm) as the grafts is prepared (DMA: N,N-dimethylacryamide, diEV: ethylviologen dimer, Np: naphthalene, PNIPAM: poly(N-isopropylacrylamide)). The grafting is based on the triple complexation among a host of cucurbit[8]uril (CB[8]) and two guests of diEV and Np, which is characterized by UV–vis spectra and ITC. Temperature sensitive property of PNIPAm moiety allows SGP to self-assemble into non-covalently connected micelle (NCCM) at high temperature. The micelles are sensitive to reducing agents, for example Na2S2O3, which breaks the current inclusion complex pair and induces aggregation.

A supramolecular graft copolymer has been prepared via inclusion complexation of CB[8] and two different guests. The structure forms non-covalently connected micelles at 40 °C with a PNIPAM core and a PDMA shell, which can be dissociated after addition of reducing reagent.Figure optionsDownload as PowerPoint slide