Cooperation of Amphiphilicity and Smectic Order in Regulating the Self-Assembly of Cholesterol-Functionalized Brush-Like Block Copolymers

Nanoparticle morphology significantly affects the application of nanometer-scale materials. Understanding nanoparticle formation mechanisms and directing morphological control in nanoparticle self-assembly processes have received wide attention. Herein, a series of brush-like amphiphilic liquid crystalline block copolymers, PChEMAm-b-POEGMAn, containing cholesteryl mesogens with different hydrophobic/hydrophilic block ratios were designed and synthesized. The self-assembly behaviors of the resulting PChEMAm-b-POEGMAn block copolymers in different solvents (tetrahydrofuran/H2O, 1,4-dioxane/H2O, and N,N-dimethylformamide) were investigated in detail. Desirable micellar aggregates with well-organized architectures, including short cylindrical micelles, nanofibers, fringed platelets, and ellipsoidal vesicles with smectic micellar cores, were observed in 1,4-dioxane/H2O with an increasing hydrophobic block ratio. Although both amphiphilicity and smectic order governed the self-assembly, these two factors were differently balanced in the different solvents. This unique supramolecular system provides a new strategy for the design of advanced functional nanomaterials with tunable morphologies