Dynamic supramolecular polymers built from cucurbit[n]urils and viologens

This review article focuses on supramolecular assemblies involving cucurbit[n]uril-based containers and viologen guests as key building elements. Cucurbit[n]urils (CB[n], n = 5-8,10) are fascinating hosts forming a wide range of inclusion complexes (caviplexes) with 4,4 '-bipyridinium salts, known as viologens, either as discrete 1:1 inclusion compounds with CB[7] or as ternary inclusion compounds involving two hosts or two guests (2:1 with CB[7] and 1:2 or 1:1:1 with CB[8]). This property is currently being actively exploited to design and prepare self-assembled dynamic stimuli-responsive supramolecular polymers including gels, vesicles, films and organized arrays of polymeric microspheres or nanoparticles. This review highlights the main benefits of such polymers and gives an overview of the achievements and progress made in this field over the past decades. (c) 2018 Society of Chemical Industry