Self-assembly of architected macromolecules: Bridging a gap between experiments and simulations

Macromolecular self-assembly is essential in life and interfacial science. A macromolecule consisting of chemically distinct components tends to self-assemble in a selective solvent to minimize the exposure of the solvophobic segments to the medium while the solvophilic segments adopt extended conformations. While micelles composed of linear block copolymers represent classic examples of such solution assembly, recent interest focuses on the self-assembly of complex macromolecules with nonlinear architectures, such as star, graft, and bottlebrush. Such macromolecules include several to hundreds of polymer chains covalently tied to a core and a backbone. The pre-programmed, non-exchangeable chain arrangement makes a huge difference in their self-assembly. The field has witnessed tremendous advances in synthetic methodologies to construct the desired architectures, leading to discoveries of exotic self-assembly behavior. Thanks to the rapid evolution of computing power, computer simulation has also been an emerging and complementary approach for understanding the association mechanism and further predicting the self-assembling morphologies. However, simulating the self-assembly of architected macromolecules has posed a challenge as a huge number of objects should be included in the simulations. Comparing experimental results with simulations is not always straightforward, as synthetic routes to well-defined model systems with systematically controlled structural parameters are not often available. In this manuscript, we propose to bridge a gap between experiments and simulations in self-assembly of architected macromolecules. We focus on the key articles in this area reporting experimental evidence and simulation details and also cover recent examples in the literature. We start with discussing simulation methodologies applicable to investigate solution self-assembly across multiple levels of chemical resolution from all-atom to particle dynamics. Then, we delve into topological design, synthesis, and simulation of nonlinear macromolecules, including dendritic/star, network, and graft/bottlebrush polymers, to understand the architectural effect on the self-assembly behavior. We expand our discourse to embrace recent advances toward realizing more complex systems. For example, self-assembly in the presence of strong Coulombic interactions, such as in the case of polyelectrolytes, geometric constraints, and other components in solutions, exemplified by inorganic fillers, are introduced. Finally, the challenges and perspectives are discussed in the final section of the manuscript.