Self-assembly and stimuli-responsive behaviours of side-chain liquid crystalline copolymers: a dissipative particle dynamics simulation approach

We conducted a dissipative particle dynamics simulation to explore the self-assembly behaviours of side-chain liquid crystalline copolymers in solvents poor for comb blocks. Our results show that the copolymers are able to self-assemble into various aggregates such as micelles and vesicles, and especially into deformed structures such as rectangle cylinders. The morphology of the aggregates depends on the concentration of copolymers and a series of structural parameters such as the length of the coil blocks. Three kinds of morphology diagrams are mapped out to gain insight into the effect of these parameters on the self-assembly behaviours. Moreover, the aggregate structures such as the spatial arrangement of the rigid side chain are analysed, and it was found that the interfaces of the aggregates are greatly influenced by the packing of the side chains. We also investigated the influence of the rod-to-coil conformation transition of side chains on the self-assembly, motivated by stimuli-responsive polymer systems. A transformation from a disk-like structure to a vesicle was observed as the rod-to-coil conformation transition occurs. A comparison between the available experimental observations and the simulation results is made, and agreement is achieved.