Abstract：Self-assembled vesicles formed by symmetrical coil-rod-coil triblock copolymer in selective solvents are investigated by dissipative particle dynamics method. The kinetic process of vesicle formation is also observed. The micelles firstly experience the fusion, elongation and deformation, and then encompass the solvents, finally close up to a vesicle membrane, where the cylindrical and disc phase are the intermediate phases transited from solid micelle to hollow vesicle. Furthermore, the effects of polymer concentration and solvent properties are discussed. Vesicle structure is only observed in the range of fp from 6%to 25%. Meanwhile, the vesicle size exhibits a well linear increase with the polymer concentration. Finally, varying the solvent properties from rod-selective to neutral then to coil-selective, the self-assembled structure of system is transited from vesicle to micelle. Under the neutral case, the lamellar structure is observed, where the rods are arranged in a highly ordered liquid crystalline phase.
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2016, Vol. 43 
