Supramolecular polymers class

Finally, Chap. 6 deals with the exploitation of biocatalysis in generating supramolecular polymers, a class of polymers where the monomers are connected via non-covalent bonds. This approach provides highly dynamic and reversible supramolecular structures, inspired by biological polymeric systems found in the intra- and extracellular space. A number of potential applications of enzymatic supramoleular polymerizations are discussed in the context of biomedicine and nanotechnology. 

Gale, P. A., Navakhun, K., Camiolo, S., Light, M. E., Hursthouse, M. B. (2002) Anion-anion assembly A new class of anionic supramolecular polymer containing 3,4-dichloro-2,5-diamido-substituted pyrrole anion dimers, J. Am. Chem. Soc. 124, 11228-11229. 

Supramolecular polymers are a relatively new class of polymers in which monomeric repeating units are held together with directional and reversible (noncova-lent) secondary interactions (Lehn, 2000), unlike conventional macromolecular species in which repetition of monomeric units is mainly governed by covalent bonding. A schematic comparison of a covalent polymer and a supramolecular polymer is shown in Fig. 1.3. 

Supramolecular polymers, 1-D aggregates of monomers formed via noncovalent interactions, attracted increasing attention as a new class of environment-responsive polymeric materials because of their reversible polymerization and depolyrnerization characteristics.In general, monomers possess two interactive moieties at which they can be connected to each other via noncovalent interactions. in supramolecular polymerization, every chain-elongation process could be regarded as equivalent events, because the associations, monomer with monomer, monomer with polymer, and polymer with polymer, involve the same chemical process. In sharp contrast, through the... 

Inclusion complexation has developed to becoming another widely exploited supramolecular interaction for the formation of supramolecular polymer networks, mostly in water [197, 198]. Several classes of macrocycles have been developed, including crown ethers [199, 200], porphyrins [201, 202], cyclophanes [203], catenanes [204], cavitands [205, 206], cryptophanes [207], calix[n]arenes [208], and carcerands [209]. Macrocyclic-based supramolecular gels can either be formed from low molecular weight precursors or from macromolecular building blocks. The following discussion focuses on the latter. 

The latter class (supramolecular polymers) include self-assembling stmctures of orgartic molecules stabilized by... 

Figure 4.1 Schematic representation of dif- polymer, (c) Supramolecular block copolymer, ferent classes of supramolecular polymers. (d) Side-chain-functionalized supramolecular (a) Small-molecule main-chain supramolec- polymer, (e) Supramolecular network, ular polymer, (b) Branched supramolecular...

Figure 1 Classification of supramoleoular polymers. Class A (reversible polymers obtained by supramolecular polymerization) is the main topio of this chapter. (From A. Ciferri. Macromol. Rapid Commun. 23 511, 2002a. Copyright Wiley-VCH 2002.)...

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