Density Functional Simulation of Spontaneous Formation of Vesicle in Block Copolymer Solutions

We carry out numerical simulations of vesicle formation based on the density functional theory for block copolymer solutions. It is shown by solving the time evolution equations for concentrations that a polymer vesicle is spontaneously formed from the homogeneous state. The vesicle formation mechanism obtained by our simulation agree with the results of other simulations based on the particle models as well as experiments. By changing parameters such as the volume fraction of polymers or the Flory-Huggins interaction parameter between the hydrophobic subchains and solvents, we can obtain the spherical micelles, cylindrical micelles or bilayer structures, too. We also show that the morphological transition dynamics of the micellar structures can be reproduced by controlling the Flory-Huggins interaction parameter.