采用耗散粒子动力学方法模拟研究了rod-coil-rod三嵌段共聚物在稀溶液中的聚集行为。分别考察了rod-coil嵌段的相互作用、溶剂性质、共聚物浓度以及coil嵌段长度对聚集体形貌的影响。模拟结果发现，随着rod-coil相互排斥作用的增加，共聚物由球形转变成洋葱状、笼形和柱状结构。随着coil嵌段疏水性的增加，笼形转变成洋葱状和补丁状结构。给出了聚集体形貌随共聚物浓度和coil长度变化的相图。当浓度较小和coil嵌段较长时，共聚物形成笼状聚集体，反之，则有利于洋葱状结构的形成。%The aggregate morphology of rod-coil-rod copolymers in a dilute solution was investigated by dissipative particle dynamics simulations. The influences of the mutual compatibility between rod and coil blocks, the solvent property, the coil length, and the copolymer concentration on the aggregate structure were studied in detail. The simulation results show that the increase of the mutual compatibility between rod and coil blocks induces transformation of the aggregate morphology from spherical, to onion-like, to cage-like, and ultimately to cylindrical. With the increase in the hydrophobicity of the coil block, the cage-like aggregate changes into an onion-like aggregate, then a patchy aggregate, and then an inverted onion-like aggregate. Final y, a phase diagram of the rod-coil-rod triblock copolymers as a function of the coil length and the copolymer concentration is presented. It shows that cage aggregates are easily formed when the coil length is long and the concentration is relatively low, whereas onion-like aggregates are preferred when the coil length is short and the concentration is moderately low.
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