Effect of Temperature on the Pathways for Spontaneous Vesicle Formation of Amphiphilic Diblock Copolymer in a Selective Solvent: A Monte Carlo Study

In this study, the kinetics of vesicle formation of AB amphiphilic diblock copolymer from an initially homogeneous state was investigated by means of Monte Carlo simulation. The pathway of spontaneous vesicle formation depended greatly on temperature. At high temperature, the amphiphilic diblock copolymer first aggregated into many small spheres, and then the small spheres merged to form oblate membrane, eventually, the oblate membrane closed up to form vesicle. However, at low temperature, the amphiphilic diblock copolymer first aggregated into many small spheres. Then, vesicles are formed via hydrophilic molecules' diffusion into the center of spherical micelles. The mechanism of this phenomenon was discussed in detail.