Application of Photoexcitation-induced Assembly Strategies to Macromolecular Assembly

In the field of molecular assembly, photocontrolled self-assembly is an intelligent strategy to regulate molecular ordering, multiscale structure and optoelectdronic properties. However, conventional photocontrolled self-assembly is implemented through a photochemical process in which photochemical reactions induce structural changes in molecules. The nanostructures and morphologies formed by photocontrolled self-assembly are often unpredictable due to the presence of side reactions and limited conversion rates. On the contrary, assembly by photophysical processes that only utilize the conformational changes of molecules from the ground state to the excited state can avoid the above drawbacks and can further promote the synergistic assembly or phase transition of the whole material system. In this paper, we focus on the photoexcitation-induced assembly (PEIA) strategy using polysulfide aromatic hydrocarbons (PAHs) as the building blocks. PAHs are capable of generating significant molecular conformational transitions from the ground state to the excited state, which are favorable for the formation of intermolecular interactions that drive molecular motions, aggregation, and assembly. In this paper, we systematically introduce the progress of exploring PEIA of polysulfide aromatics at the molecular level, further demonstrate that PEIA of polysulfide aromatics can synergistically drive molecular motions and phase transitions in polymer systems, and provide an outlook on the key issues and important challenges for the future development of PEIA.