Mesoscale Simulation of Amphiphlic Molecules by VR Network

采用耗散粒子动力学（DPD）算法对ab -二聚体在W单体溶液中的结构形成进行了中尺度模拟。仿真模型采用修正的Jury模型[Jury， S. et al.]。“用耗散粒子动力学模拟两亲性中间相”，物理学。化学。化学。理论物理。Vol.1(1999) pp.2051-2056]，它代表了表面活性剂六乙二醇十二烷基醚（C12E6）和水（H2O）的自组装力学。得到了与Jury结果相同的相图。我们还发现，六方相（H1）的形成比层状相（La）的形成需要更长的时间。第二步，采用Jury模型进行耗散粒子动力学（DPD）模拟，通过改变亲水分子与水分子之间的相互作用势，定性地阐明了相结构的亲水性依赖关系。通过改变亲水性珠与水分子之间的相互作用电位系数x=-20、0、10和20，在无因次温度T=0.5和两亲性分子在水中的浓度φ=50%时，相结构发展为片层相（x=-20）、六边形相（x=0）和胶束相（x=10）。当x=20时，亲水珠与水分子之间发生相分离。

Meso-scale simulation of structure formation for AB-dimers in solution W monomers was performed by dissipative particle dynamics (DPD) algorithm. As a simulation model, modified Jury Model was adopted [Jury, S. et al. "Simulation of amphiphilic mesophases using dissipative particle dynamics," Phys. Chem. Chem. Phys. Vol.1(1999) pp.2051-2056], which represents mechanics of self assembly for surfactant hexaethylene glycol dodecyl ether(C12E6) and water(H2O). The same phase diagram as Jury's result was obtained. We also found that it takes a longer time to form the hexagonal phase (H1) than to form the lamellar phase (La).As the second step, the hydrophilicity dependence of the phase structure was clarified qualitatively by varying the interaction potential between hydrophilic molecules and water molecules in a dissipative particle dynamics (DPD) simulation using the Jury model. By varying the coefficient of the interaction potential xbetween hydrophilic beads and water molecules as x=-20,0,10,and 20,at a dimensionless temperature of T=0.5 and a concentration of amphiphilic molecules in water of φ=50%, the phase structures grew to lamellar (x=-20), hexagonal (x=0), and micellar (x=10) phases. For x=20, phase separation occurs between hydrophilic beads and water molecules.