Supramolecular Polymer Networks: Preparation, Properties, and Potential

Supramolecular polymer networks consist of macromolecules interconnected by transient, noncovalent bonds such as those through hydrogen bonding, transition metal complexation, hydrophobic interaction, ionic attraction, or π–π stacking. These networks form an extraordinarily useful class of soft, stimuli-sensitive materials. Although they assemble to strong materials under favorable conditions, they are easily disassembled under other conditions. This ambivalent nature renders supramolecular polymer networks useful for applications in drug delivery, tissue engineering, self-healing, and shape-memory materials. These applications require a deep and comprehensive understanding of the physical chemistry of supramolecular networks, with a particular view to the complex interplay between their structure, dynamics, and properties. Approaches that have attempted to derive such knowledge are often based on investigations of supramolecular polymer networks in the melt or of supramolecular polymer networks swollen in organic media. These approaches are reviewed in the first part of this chapter. In the second part, we focus on the preparation and characterization of supramolecular hydrogels based on synthetic and natural precursors and reveal their utility and potential in life science applications.