Review on polydopamine supramolecular ordering – mechanism elucidation and application in 2D nanocomposites fabrication

Polydopamine has gained recognition in surface modification and construction of functional nanocomposites, among others, due to its extraordinary adhesive properties. However, despite the clear tendency to form in a supramolecularly ordered manner, this mechanism has remained almost completely overlooked. At the same time, polymerization-induced self-assembly has been a hot topic in recent years. In this review, we emphasize the laws and relationships governing the formation of polydopamine nanoparticles, functional coatings and free-standing films in an ordered or semi-ordered manner. We took advantage of both computer simulations and basic research to summarize the state of the art and to set possible guidelines for further research work aimed at full understanding and precise control of the polydopamine supramolecular ordering process. We also present examples of application studies in which the self-assembly tendency of polydopamine and reversible cross-linking through physical interactions were used to create advanced 2D nanocomposites, hydrogels, etc. Finally, we also present future perspectives and research guidelines and encourage further work on this exceptional biomimetic polymer.