In the past 60 years, polymers have revolutionized our lives. Their low price, high processability, and exceptional mechanical properties have led to the use of polymers in ever more sophisticated applications.
Presently, a strong scientific interest in 'smart' polymers -polymers that respond to changes in temperature, solvent, or the presence of 'signal' chemicals -is beginning to expand the potential field of applications for such materials even further.
Key to the responsiveness of smart materials is the reversibility of the noncovalent interactions that lead to the change in properties. In nature, responsive structural polymers abound and their capacity to respond is often brought about by reversible assembly/disassembly. Scaffolds, such as those that constitute the cellular skeleton, are formed only where and when they are required, and they are disassembled into small building blocks when their task has been fulfilled. As opposed to a purely macromolecular approach, such a modular, supramolecular strategy allows a fast and efficient response to changing needs in the cellular cycle.
The field of supramolecular chemistry has been developed over the past 25 years by synthetic chemists, inspired by the ubiquity of reversible, yet highly specific, intermolecular processes in nature. Supramolecular polymers form the most recent branch in the tree of 'chemistry beyond the covalent bond', as supramolecular chemistry is sometimes called. Despite their short history, supramolecular polymers are already beginning to find commercial use in applications that take advantage of the reversibility and responsiveness of noncovalent interactions.