Brownian Molecular Dynamics Simulation on Self-Assembly Behavior of Rod−Coil Diblock Copolymers
Brownian Molecular Dynamics Simulation on Self-Assembly Behavior of Rod−Coil Diblock Copolymers
复制标题
DOI：
10.1021/ma062064l
复制
发表时间：
2007-02
期刊：
影响因子：
5.5
通讯作者：
Shaoliang Lin;N. Numasawa;A. Nose;Jiaping Lin
中科院分区：
文献类型：
--
作者：
Shaoliang Lin;N. Numasawa;A. Nose;Jiaping Lin
用布朗分子动力学方法模拟了棒状-线团嵌段共聚物的自组装行为。共聚物分子由一定的小球组成的线性链表示，小球之间通过键的伸缩势连接。杆块的刚度由用于在基本上为零的键角处的弯曲的谐波势引入。研究了这类共聚物形成的胶束结构和棒状嵌段的分子堆积。随着杆对的Lennard-Jones（LJ）相互作用eRR的变化，发现聚集结构的转变。在较高的eRR下，棒块倾向于在取向上对齐并在芯中以六边形包装以形成近晶状盘结构。随着eRR的降低，盘状胶束逐渐转变为一种新的串状结构，在这种结构中，填充在核中的棒状块体发生扭曲，并进一步断裂成一些小的聚集体，直到单聚体。计算了杆块的回转半径和序参量，证实了这种方法的正确性。
Brownian molecular dynamics simulations are carried out on the self-assembly behavior of rod−coil diblock copolymers. The copolymer molecule is represented by a linear chain consisting of definite beads connecting by harmonic bond stretching potential. The rigidity of the rod block is introduced by harmonic potential for bend at a substantially zero bond angle. The micelle structures formed by such copolymers and molecular packing of rod blocks are investigated. Transitions of aggregate structure are found with changing Lennard-Jones (LJ) interaction eRR of rod pairs. The rod blocks tend to align orientationally and pack hexagonally in the core to form a smectic-like disk structure at the higher eRR. With decreasing eRR, a disk micelle is gradually changed to a new string structure, where the twisting of rod blocks packing in the core has been discovered and further breaks into some small aggregates until unimers. The radius of gyration and order parameter of rod blocks are calculated to confirm such a tr...