ABSTRACT
I. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 II. Equilibrium Polymers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80 III. Thermally Activated Equilibrium Polymers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84 IV. Chemically Activated Equilibrium Polymers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87 V. Coordination Polymers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88 VI. Rods, Rings, and Worms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89 VII. Helical Aggregation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 VIII. Interacting Supramolecular Polymers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97 IX. Coupling to External Fields . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99 X. Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
I. INTRODUCTION
The term supramolecular polymer applies to any type of polymer-like assembly that spontaneously forms by the reversible linear aggregation of one or more type of molecule in solution or in the melt. The crucial factor discriminating supramolecular from conventional or so-called “dead” polymers, is that for the former the monomeric and the polymeric states are in thermal equilibrium with each other, while for the latter this is not so (on the relevant experimental timescale). Examples of supramolecular polymers include the so-called giant surfactant micelles [1], peptide β-sheet ribbons [2], self-assembled stacks of discotic molecules [3], protein fibers such as those formed by sickle cell hemoglobin [4], and so on. Chains of colloidal particles found in quite diverse contexts [5-8] and living polymers of chemically reactive species [9] also belong to the class of supramolecular polymers, if only in principle.
