Rotaxanes morphologies

The simplest rotaxane morphology, as defined in the Introduction and represented in Figure 2.1, is noted as [2]-rotaxane to express that it is made up with two components a ring and a dumbbell.13 More generally, an [n]-rotaxane contains n — 1 rings threaded onto a dumbbell component. Figure 2.4 shows several relatively simple rotaxane morphologies that have been realized. 

Until now, we considered the simplest rotaxane morphology, as defined in the introduction and represented in Figure 1. This molecular system is noted as [2]-... 

Fig. 34 Example of mechanized mesoporous silica nanoparticles (MSNPs). SEM (a) and TEM (b) images show the structure and morphology of the MSNP platform [238]. (c) Structural formula of the a-cyclodextrin-based snap-top rotaxane that blocks the pores of an enzyme-cleavable mechanized MSNP. The stopper is connected to the stalk (dumbbell) by an ester or an amide bond [254]. (d) Release profile of rhodamine B from the snap-top MSNP. The addition of an esterase enzyme cleaves the ester bond, releasing the stopper, a-cyclodextrin, and cargo from the nanoparticles, which is monitored by the fluorescence intensity of rhodamine B. Controls employing an amide bond snap-top or deactivated enzyme do not release significant amounts of cargo...

This chapter gives an overview of the literature on microstructures, "photonic" polymers, fullerence-based polymers, cyclics, rotaxanes, and dendrimers. The properties of polymers with other architectures and morphologies are discussed in various other chapters of this handbook. 

J. F. Moulin, J. C. Kengne, R. Kshirsagar, M. Cavallini, F. Biscarini, S. Leon, F. Zerbetto, G. Bottari, and D. A. Leigh, Self-organization of rotaxane thin films into spatially correlated nanostructures morphological and structural aspects,/ Am. Chem. Soc., 128, 526-532 (2006). 

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